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1.  Role of ultrasound in the assessment of benignity and malignancy of parotid masses 
Wu, S | Liu, G | Chen, R | Guan, Y
Dentomaxillofacial Radiology  2012;41(2):131-135.
This study aimed to investigate the value of ultrasound in the identification of benign and malignant parotid masses.
Data of 189 patients with parotid gland masses undergoing ultrasound-guided fine-needle aspiration (FNA), core biopsy or surgery were reviewed retrospectively and the presumed sonographic diagnoses were compared with the histopathology. The sensitivity, specificity and accuracy of sonographic diagnoses were assessed and the sonographic characteristics of those lesions, including shape, margin, echogenicity, echotexture and vascularization, were studied.
Of the 189 patients, the final pathological diagnosis included 18 malignant tumours and 171 benign masses; the presumed sonographic diagnoses showed 165 cases as benign and probably benign masses (11 cases were confirmed malignant, 154 cases benign) and 24 cases were diagnosed as probably malignant and malignant masses (7 cases were confirmed malignant, 17 cases benign). The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of ultrasound for the diagnosis of parotid gland masses were 38.9%, 90.1%, 29.2%, 93.3% and 85.2%, respectively, and accuracy for malignant masses was 20%. The sonographic characteristics of parotid masses between benign and malignant lesions had no significant differences. The parotid gland masses in this study included pleomorphic adenoma, Warthin's tumour, retention cyst, haemangiomas, chronic granuloma, lymphoma, fibrolipoma, abscess, basal cell adenoma, oncocytoma, lymphatic tuberculosis, myoepithelioma, neurilemmoma, mucoepidermoid carcinoma, adenoid cystic carcinoma, alveolar soft part sarcoma and retinal blastoma (metastasis).
It is challenging to use sonography for differentiating between benign and malignant parotid gland masses. To make a definite diagnosis, ultrasound-guided FNA or core biopsy is advocated.
PMCID: PMC3520365  PMID: 22116132
parotid gland; mass; benign; malignant; ultrasound
2.  Is There a Role for PET/CT Parameters to Characterize Benign, Malignant, and Metastatic Parotid Tumors? 
Assessment of benign and malignant lesions of the parotid gland, including metastatic lesions, is challenging with current imaging methods. Fluorine-18 FDG PET/CT is a noninvasive imaging modality that provides both anatomic and metabolic information. Semiquantitative data obtained from PET/CT, also known as PET/CT parameters, are maximum, mean, or peak standardized uptake values (SUVs); metabolic tumor volume; total lesion glycolysis; standardized added metabolic activity; and normalized standardized added metabolic activity. Our aim was to determine whether FDG PET/CT parameters can differentiate benign, malignant, and metastatic parotid tumors.
Thirty-four patients with parotid neoplasms underwent PET/CT before parotidectomy; maximum SUV, mean SUV, peak SUV, total lesion glycolysis, metabolic tumor volume, standardized added metabolic activity, and normalized standardized added metabolic activity were calculated on a dedicated workstation. Univariate analyses were performed. A ROC analysis was used to determine the ability of PET/CT parameters to predict pathologically proven benign, malignant, and metastatic parotid gland neoplasms.
Fourteen patients had a benign or malignant primary parotid tumor. Twenty had metastases to the parotid gland. When the specificity was set to at least 85% for each parameter to identify cut points, the corresponding sensitivities ranged from 15% to 40%. Assessment of benign versus malignant lesions of parotid tumors, as well as metastasis from squamous cell carcinoma versus other metastatic causes, revealed that none of the PET/CT parameters has enough power to differentiate among these groups.
PET/CT parameters, including total lesion glycolysis, metabolic tumor volume, standardized added metabolic activity, and normalized standardized added metabolic activity, are not able to differentiate benign from malignant parotid tumors, primary parotid tumors from metastasis, or metastasis from squamous cell carcinoma and nonsquamous cell carcinoma metastasis.
PMCID: PMC4993674  PMID: 27276388
benign; FDG; malignant; parameter; parotid; PET/CT; tumor
3.  The accuracy of fine-needle aspiration cytology for diagnosis of parotid gland masses: a clinicopathological study of 114 patients 
Journal of Applied Oral Science  2016;24(6):561-567.
Fine-needle aspiration cytology is a valuable method for preoperative assessment of head and neck tumors. However, its accuracy in detection of salivary gland masses is controversial compared with other methods. The aim of this work was to evaluate the effectiveness and accuracy of fine-needle aspiration cytology (FNAC) in the diagnosis of parotid gland masses.
Material and Methods
Over a 10-year period, 126 parotid gland masses were resected. Retrospective chart reviews of 114 patients were performed. The results of FNAC and final histological diagnosis were compared and the accuracy of FNAC was determined.
Final histological evaluation revealed 11 malignant tumors and 103 benign lesions. Pleomorphic adenoma was the most common neoplasm (63%), followed by Warthin’s tumor (17.5%). The sensitivity of FNAC in detecting malignant tumors was 73% and the specificity was 97%. Positive predictive value (PPV) was 73% and negative predictive value (NPV) was 97%. The overall accuracy of FNAC in detecting parotid masses was 95%. False-negative diagnosis was found in mucoepidermoid carcinoma, acinic cell carcinoma, and epithelial-myoepithelial carcinoma whereas there was false-positive diagnosis in cases of pleomorphic adenoma and normal parotid gland tissue.
FNAC is a reliable minimally invasive diagnostic method with a high sensitivity in diagnosis of lesions in parotid glands. The sensitivity of detection of malignant tumors in parotid glands was low due to the biopsy technique used, and depended on tumor location. Postoperative complications decreased after superficial parotidectomy.
PMCID: PMC5161254  PMID: 28076460
Fine-needle; Citology; Parotid disease; Diagnosis; Biopsy
4.  Accuracy of preoperative fine needle aspiration in diagnosis of malignant parotid tumors 
Saudi Medical Journal  2017;38(10):1000-1006.
To determine the diagnostic accuracy of fine needle aspiration (FNA) for detecting malignant parotid tumors.
We conducted a retrospective study of all patients diagnosed with benign or malignant parotid gland tumors in King Abdulaziz University Hospital, Jeddah, Saudi Arabia, between January 2004 and May 2015. The records of 65 subjects were obtained. Histopathological findings and data from FNA examinations were obtained from medical records. Twenty-three subjects were excluded due to missing FNA, histopathology results or both. The sensitivity, specificity, negative predictive value, and positive predictive value of FNA for detecting malignant lesions were estimated and compared with the gold standard, histopathology.
The specimens of 5 cases were insufficient for diagnosis; therefore, 38 cases were diagnosed by FNA and had histopathological reports. Three cases were diagnosed positive for cancer using histopathology and missed by FNA, 3 were diagnosed as malignant lesions using both FNA and histopathology, and 32 cases were determined benign based on histopathology and FNA analysis. The total prevalence of parotid malignancies was 15.8%. The sensitivity of FNA for detecting malignancy was 50%, and the specificity was 100%; with a positive predictive value of 100% and negative predictive value of 91.4%.
Fine needle aspiration is a highly specific, but only moderately sensitive test. We support the use of this method as an initial tool for diagnosing parotid gland malignancies, as it is a safe, rapid, and painless procedure, compared to histopathology.
PMCID: PMC5694632  PMID: 28917063
5.  Importance of Sonoelastography in Assessing Non-Thyroid Neck Masses 
To evaluate the feasibility and value of sonoelastography in assessing non-thyroid neck masses.
Non-thyroid neck masses requiring surgical interventions were evaluated using conventional B-mode ultrasonography (US) (size, short/long axis rate, shape, hilum, echogenity, calcification, necrosis, and peripheral edema) and sonoelastograpy (SE) with strain ratio (SR) and elasticity score (ES) before surgery. These parameters were compared with the histopathological examination.
In total, 116 non-thyroid neck masses (66 lymph node, 35 parotid gland, eight submandibular gland, and seven cervical mass) of 89 patients (51 men, 38 women) with a mean age of 50.3±15.1 (19–79) years were evaluated. Thirty-seven malignant lymph nodes (23 metastatic and 14 lymphoma), seven malignant parotid tumors, two malignant submandibular tumors, 29 benign lymph nodes, 28 benign parotid lesions, and six benign submandibular lesions were evaluated. Mean SR and ES values of malignant masses were 6.3/3.2 for lymph nodes, 5.5/3.3 for the parotid gland, and 4.2/3 for the submandibular gland. Mean SR and ES values of benign lesions were 2.0/2.1 for lymph nodes, 4.4/3.2 for the parotid gland, and 3.2/3 for the submandibular gland. SR and ES were significantly higher for malignant masses compared with those for benign ones. SR was more predictive than ES in evaluating malignant lymph nodes. The area under the curve was 0.917(0.827–1.00) (p<0.05) for SR in differentiating benign-malignant lymph nodes, and the upper cut-off value was two. SR and ES were higher in the malign parotid and submandibular gland lesions than the benign ones, but the difference was not statistically significant.
Strain ratio value could be a useful parameter in differentiating benign-malignant lymph nodes. More studies are necessary for differentiating benign-malignant parotid and submandibular lesions using SE.
PMCID: PMC5782921
Elastography; differential diagnosis; head and neck neoplasms; lymph nodes; salivary glands
6.  Role of Fine-Needle Aspiration Biopsy in the Management of Salivary Gland Masses 
Fine-needle aspiration biopsy (FNAB) is widely used in the management of salivary gland masses. Its main advantage is its ability to differentiate benign from malignant disease. In this study, we aimed to evaluate the diagnostic ability of FNAB in salivary gland masses.
The records of patients who had undergone FNAB before parotidectomy or submandibular gland excision between 2005 and 2013 were retrospectively analyzed. FNAB results were classified as negative, positive, suspicious for malignancy, and non-diagnostic. Preoperative FNAB results were compared with definitive histopathological results. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of FNAB results were calculated.
A total of 285 patients were enrolled. Among them, 230 (80.7%) had parotid gland and 55 (19.3%) had submandibular gland masses. Following a definitive histopathological examination, the most common benign tumor was pleomorphic adenoma (52.6%), whereas malignant tumors were mucoepidermoid carcinoma (2%) and squamous cell carcinoma (2%). The sensitivity, specificity, PPV, NPV and accuracy of FNAB results were 76.9%, 95.4%, 75%, 95.9%, and 92.6%, respectively. The rate of a suspicious cytology was 5.2% (15 patients) and that of a non-diagnostic cytology was 8.8% (25 patients).
FNAB is a safe and simple diagnostic tool for the diagnosis of salivary gland masses and has a relatively high sensitivity and specificity. It may provide valuable information for patient counselling and surgical planning. The major drawbacks include a lower sensitivity than specificity and a relatively high rate of non-diagnostic results.
PMCID: PMC5782959
Salivary gland; fine-needle aspiration biopsy; neoplasia; management
7.  The differential diagnosis of parotid gland tumors with high-resolution ultrasound in otolaryngological practice 
The aim of the study is to define the utility of ultrasound (US) in differentiating benign from malignant parotid tumors as well as pleomorphic adenomas (PA) from monomorphic adenoma (MA). Seventy-two consecutive parotid gland tumors were analysed with high-resolution ultrasonography (12 MHz) with color Doppler imagining. The histopathological diagnosis was confirmed after parotidectomy for each lesion. The sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) for the US were established. Receiver operating characteristic curves were constructed to determine the predictive values of echogenicity, heterogeneity, and vascularity on color Doppler. Area under the curve (AUC) was calculated for each parameter considered. The analysed material included 27 MA, 26 PA, 1 basal cell adenoma, 8 inflammatory conditions, and 10 malignant neoplasms. The sensitivity, specificity, and accuracy of US in differentiation of malignant from benign lesions in the parotid gland were 60, 95.2, and 90.3%, respectively. The predictive values were: PPV 66.8% and NPV 93.6%. Differentiating diagnoses between PA and MA with US resulted in a sensitivity of 61.5%, specificity of 81.5%, and accuracy of 73.1%. The predictive values were: PPV 50% and NPV 68.8%, respectively. For distinguishing malignant from benign tumors, the highest AUC values noted were for heterogeneity and vascularization (0.8 and 0.743, respectively). The AUC values were the highest for hypoechogenicity and vascularization in separating PA from MA (0.718 and 0.685, respectively).
PMCID: PMC5500678  PMID: 28612315
Parotid gland tumor; Ultrasound; Pleomorphic adenoma; Monomorphic adenoma; Malignant parotid gland neoplasms
8.  Diagnostic Criteria on 18F-FDG PET/CT for Differentiating Benign from Malignant Focal Hypermetabolic Lesions of Parotid Gland 
We investigated PET/CT diagnostic criteria for differentiating benign from malignant parotid lesions with focal 18F-FDG uptake.
The subjects of the study were 272 patients who exhibited focal 18F-FDG uptake of the parotid gland. Sixty-eight pathologically confirmed parotid lesions from 67 patients were included. The maximum SUV (SUVmax), uptake patterns (homogeneous vs. heterogeneous), size measured by CT, maximum Hounsfield units (HUmax) and margins on CT (well vs. ill defined) of each parotid lesion on PET/CT images were compared with final diagnoses.
Thirty-two parotid lesions were histologically proven to be malignant. There were significant differences in uptake patterns (cancer incidence, heterogeneous:homogeneous = 79.2%:29.5%, p < 0.0001) and margins on CT (cancer incidence, ill:well defined = 84.4%:13.3%, p < 0.0001) between benign and malignant lesions. The cancer risks of parotid lesions were 89.5% with heterogeneous uptake and ill-defined margins, 70.6% with heterogeneous uptake or ill-defined margins (no overlap in subjects) and 9.3% with homogeneous uptake and well-defined margins (p < 0.0001). When any lesion with heterogeneous uptake or ill-defined margins was regarded as malignant, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 90.6% (29/32), 80.6% (29/36), 80.6% (29/36), 90.6% (29/32) and 85.6% (58/68), respectively. For predicting malignancy, combined PET/CT criteria showed better sensitivity, NPV and accuracy than PET-only criteria, and had a tendency to have more accurate results than CT-only criteria. There were no significant differences in SUVmax, size or HUmax between benign and malignant lesions.
Uptake patterns and margins on CT are useful PET/CT diagnostic criteria for differentiating benign from malignant lesions.
Electronic supplementary material
The online version of this article (doi:10.1007/s13139-012-0135-y) contains supplementary material, which is available to authorized users.
PMCID: PMC4042991  PMID: 24900041
F-FDG; PET; PET/CT; Parotid gland; Cancer
9.  An audit of surgery of the parotid gland. 
The management of patients undergoing 50 surgical procedures to the parotid gland was reviewed. The overall accuracy of fine needle aspiration cytology was 87%, false-positive and false-negative rates for malignant disease both being 4%. The sensitivity, specificity and accuracy of fine needle cytology for malignant parotid tumours was 66%, 95%, and 91%, respectively, that of benign tumours (pleomorphic adenoma or Warthin's tumour) being 88%, 83% and 87%, respectively. Sensitivity, specificity and accuracy for the remaining (principally inflammatory) parotid diseases was 100%, 95% and 96%, respectively. The predictive value of a positive test for malignant tumours, benign tumours and inflammatory conditions was 66%, 94% and 75%, respectively. The negative predictive value for these conditions was 95%, 71% and 100%, respectively. Facial nerve weakness after parotidectomy occurred in three patients (8.8%), being permanent in two cases (both malignant). Although Frey's syndrome was not recorded in any of the notes, careful follow-up revealed two cases (6%). To date there have been no local recurrences after excision of either benign or primary malignant parotid masses. One patient with squamous cell carcinoma metastatic to the parotid gland died, despite block dissection of the neck and radiotherapy. This small series with a limited follow-up suggests that diseases of the parotid gland can be managed by general surgeons with an interest in this field. Although fine needle aspiration and ultrasonic scan may be helpful, the decision to operate should be made on clinical grounds.
PMCID: PMC2502101  PMID: 7598416
10.  Fine needle aspiration cytology in diagnosis of salivary gland lesions: A study with histologic comparison 
CytoJournal  2013;10:5.
Fine needle aspiration cytology (FNAC) has been employed in pre-operative diagnosis of salivary gland lesions for many years. Various studies in the existing literature have shown a wide range of sensitivity and diagnostic accuracy of cytologic diagnosis. This study was aimed at evaluating salivary gland FNAC for sensitivity, specificity and diagnostic accuracy at a tertiary care center.
Materials and Methods:
This study included 80 patients who underwent pre-operative FNAC followed by surgical procedure and histologic examination. The histologic diagnosis was considered as the gold standard. FNAC diagnosis was compared with the final histologic impression and concordance assessed. Sensitivity, specificity and diagnostic accuracy of FNAC for malignant lesions were calculated.
Of the 80 cases, majority (67.5%) involved the parotid gland. Eight cases (10%) were non-neoplastic lesions, comprised of sialadenitis, retention cyst and sialadenosis. Of a total of 72 neoplasms, 58 were benign and 14 were malignant salivary gland tumors. A cyto-histologic concordance of benign diagnosis was achieved in 85.7% of cases and for malignant lesions in 92.8% of the malignant tumors. FNAC showed a sensitivity of 92.8%, specificity of 93.9%, a positive predictive value of 81.2% and negative predictive value of 98.4% for malignant salivary gland tumors. There was one false-negative diagnosis and four false-positive cases diagnosed on FNAC.
FNAC continues to be a reliable diagnostic technique in hands of an experienced cytopathologist. The sensitivity of diagnosis of malignant lesions is high, though the rate of tumor type-specific characterization is lower, due to variable cytomorphology. In difficult cases, histologic examination may be employed for accurate diagnosis.
PMCID: PMC3623452  PMID: 23599724
Fine needle aspiration; histologic diagnosis; salivary gland; sensitivity; specificity
11.  Parotid Gland Solitary Fibrous Tumor: A Case Report and Clinicopathologic Review of 22 Cases from the Literature 
Head and Neck Pathology  2011;6(1):21-31.
Solitary fibrous tumors (SFTs) are rare tumors in the head and neck, and even more so in the parotid gland. The mass-like clinical presentation and histologic features result in frequent misclassification, resulting in inappropriate clinical management. There are only a few reported cases in the English literature. Twenty-one patients with parotid gland solitary fibrous tumor were compiled from the English literature (Medline 1960–2011) and integrated with this case report. The patients included 11 males and 11 females, aged 11–79 years (mean, 51.2 years), who presented with a parotid gland painless mass gradually increasing in size or with compression symptoms, with a mean duration of symptoms of 24.7 months. The mean tumor size was 4.5 cm. Grossly, all tumors were described as well-circumscribed to encapsulated, firm, homogenous white to tan masses. Seven patients had a preoperative fine needle aspiration performed, with the majority interpreted to represent pleomorphic adenoma or cementifying fibroma. Histologically, the tumors were well circumscribed, although many tumors showed focally entrapped normal salivary gland acini and ducts at the edge. The tumors were cellular, arranged in haphazard short interlacing fascicles of spindled to epithelioid cells. The spindled cells showed tapering cytoplasm with monotonous, round to oval nuclei with coarse nuclear chromatin distribution. Keloid-like to wiry collagen was present between the neoplastic cells. Mitoses were identified in most cases, while necrosis was absent. Isolated, patulous vessels were present, but a well developed “hemangiopericytoma-like” vascular pattern was not seen. Three tumors were classified as malignant, showing marked nuclear pleomorphism and increased mitoses. When immunohistochemistry was performed, all tumors showed strong and diffuse vimentin, with a majority showing CD34, bcl-2 and CD99 immunoreactivity; all cases tested were negative for S100 protein, cytokeratin, EMA, CAM5.2, smooth muscle actin, muscle specific actin, desmin, MYOD1, myogenin, CD117, GFAP, CD31, FVIII-RAg, collagen IV, p63, p53, calponin, caldesmon, CD56, NFP, and ALK-1. The principle differential diagnoses include pleomorphic adenoma, myoepithelioma, nodular fasciitis, schwannoma, fibromatosis coli, spindle cell “sarcomatoid” carcinoma, and spindle cell melanoma. All patients were managed with surgery, while two patients also received radiation therapy. Metastatic disease was identified in one patient immediately after excision. All patients with follow-up were alive without evidence of disease (n = 18), but the average follow-up is only 1.9 years. One patient is alive with disease at 12 months. Parotid gland SFT is a rare tumor, usually presenting in middle aged adults as a slowly growing mass. Characteristic histologic appearance with CD34 and bcl-2 immunoreactivity support the diagnosis. Surgery is the treatment of choice to yield a good outcome.
PMCID: PMC3311954  PMID: 22002440
Solitary fibrous tumor; Hemangiopericytoma; Parotid gland; Salivary gland; Soft tissue; Immunohistochemistry; Prognosis; Survival; Differential diagnosis
12.  Metastatic hepatocellular carcinoma to the parotid gland: Case report and review of the literature 
Hepatocellular carcinoma, the most frequent primary hepatic tumor, metastasizes in more than 50% of cases. However, parotid gland metastatic HCCs are very uncommon. We report a patient in whom the finding of a left parotid mass revealed metastatic HCC.
A thirty-six-year-old male presented with a round palpable left neck mass that persisted for 3 months. He had received right hemihepatectomy for hepatocellular carcinoma (HCC). Preoperative evaluation revealed a benign tumor of the parotid gland. We performed superficial parotidectomy. Metastatic hepatocellular carcinoma of the parotid gland was diagnosed.
Although HCC metastases to the oral cavity have been reported, to date, only 4 cases HCC metastasis to the parotid gland have been reported. Although clinicians and cytopathologists alike both agree that salivary gland fine needle aspiration biopies (FNABs) are highly useful and safe diagnostic alternatives to biopsies and resections, we believe that in specific clinical situations, awareness of potential diagnostic pitfalls in salivary gland FNAB is a necessary part of the microscopic interpretations of these lesions.
Although rare, since HCC can metastasize to the parotid gland, high suspicion should be maintained in a patient presenting with a parotid mass with a history of HCC. In addition, since potential diagnostic pitfalls in salivary gland fine-needle aspiration (FNA) biopsies exist, incisional or excisional biopsy may be necessary for definite diagnosis of metastatic HCC to the parotid gland.
PMCID: PMC3537927  PMID: 23123420
HCC, hepatocellular carcinoma; FNA, fine-needle aspiration; Metastatic hepatocellular carcinoma; Parotid gland; Fine-needle aspiration
13.  Diffusion weighted magnetic resonance imaging in the diagnosis of parotid masses. Preliminary results 
Saudi Medical Journal  2016;37(12):1412-1416.
To demonstrate the diagnostic potentials of MRI, diffusion weighted imaging (DWI), and apparent diffusion coefficient (ADC) mapping in the detection of parotid masses correlated to the histopathological results.
Study design was retrospective. Fifteen patients with parotid gland masses were included as the study group and contralateral normal parotis glands of same patients were taken as the control group. Patients with bilateral parotid gland tumors were excluded, 7 right-sided and 8 left-sided parotid masses were included in the research. The study took place at the Department of Radiology, Ankara, Turkey, between May 2012 and September 2014.
Apparent diffusion coefficient measurements of 15 parotis tumors in 1000 and 750 sec/mm2 b-values with comparison to the contralateral normal gland parenchyma were demonstrated. Neurofibromas was predicted as the highest, and lipomas as the lowest ADC values. Pleomorphic adenomas, Warthin’s tumor, and normal parotid parenchyma indicate significant statistical differences from each other on the basis of mean ADC values (p<0.05).
The DWI and ADC mapping of parotis gland could aid in the differential diagnosis of benign and malignant masses.
PMCID: PMC5303784  PMID: 27874161
14.  Application of DTI and ARFI imaging in differential diagnosis of parotid tumours 
Dentomaxillofacial Radiology  null;45(6):20160100.
To explore the utility of diffusion tensor imaging (DTI) and acoustic radiation force impulse (ARFI) imaging in the diagnosis of parotid tumours.
51 patients with parotid tumours were examined with DTI on 3.0-T MRI and ARFI imaging on an ultrasound scanner before surgery. Values of apparent diffusion coefficient (ADC), fractional anisotropy (FA) and shear-wave velocity (SWV) were calculated and analyzed with independent samples Wilcoxon–Mann–Whitney test. Cut-off values, sensitivity and specificity were calculated with receiver-operating characteristic (ROC) curve analysis. The value of combination was calculated through parallel test for the cut-off value of ADC, FA and SWV (combination = 0 or 1); then, ROC analysis was performed with pathological results as the gold standard to calculate the sensitivity and specificity for the combination of the three parameters distinguishing benign and malignant parotid tumours. Pathological diagnosis for every patient was made post-operatively from the tumour tissue taken during operation.
There was a significant difference between benign and malignant tumours in the values of ADC, FA and SWV (p = 0.032, p = 0.011 and p < 0.0001); a significant difference in the values was also found between pleomorphic adenoma and malignant tumour (p = 0.0012, p < 0.0001 and p = 0.0002). The diagnosis cut-off points between benign and malignant tumours for ADC, FA and SWV were 1.02 × 10−3 mm2 s−1, 0.24 and 2.76 m s−1, respectively; the sensitivity for ADC, FA and SWV was 87.50, 62.50 and 68.75%; the specificity was 45.71, 82.86 and 97.14%. Analysis of the combination of the three parameters increased the sensitivity, specificity, Youden index and area under the ROC curve compared with analysis of each parameter alone for distinguishing benign and malignant tumours.
The diagnostic value of the combination of the three parameters for distinguishing benign and malignant parotid tumours is the best; SWV is the preferred indicator. Parameters of DTI and ARFI may reflect the histological characteristics of parotid tumours and predict benignancy and malignancy and could provide quantitative information about the tumour. Combination of DTI with ARFI imaging had obvious advantage for the diagnosis of parotid tumours than each alone.
PMCID: PMC5124776  PMID: 27351345
parotid tumour; diffusion tensor imaging; acoustic radiation force impulse; MRI; ultrasound
15.  Parotid Gland Nodular Fasciitis: A Clinicopathologic Series of 12 Cases with a Review of 18 Cases from the Literature 
Head and Neck Pathology  2014;9(3):334-344.
Nodular fasciitis (NF), very uncommon in the parotid gland, is a benign myofibroblastic proliferation that may be mistaken for other neoplastic proliferations. The mass-like clinical presentation and histologic features result in frequent misclassification, resulting in inappropriate clinical management. There are only a few reported cases in the English literature. Cases within the files of the authors’ institutions (retrospective) confined to the parotid gland were compared to cases reported in the English literature (Medline 1966–2014). The patients included five females and seven males, aged 11–70 years (mean 45.2 years). All patients presented with a mass lesion, present on average 1.9 months, without a documented history of trauma. The lesions were 0.7–5.2 cm (mean 2.2 cm). Seven patients had fine needle aspiration. The majority of the lesions were circumscribed (n = 9), composed of spindle-shaped to stellate myofibroblasts (MF) arranged in a storiform growth pattern, juxtaposed to hypocellular myxoid tissue-culture-like areas with extravasation of erythrocytes. Dense, keloid-like collagen (n = 7) and occasional giant cells were seen (n = 6). Mitotic figures (without atypical forms) were readily identifiable (mean 4/10 HPFs). By immunohistochemical staining, the MF were reactive with vimentin, actins, and calponin, while the histiocytes were reactive with CD68. All patients had surgical excision. One patient developed local recurrence (12 months later). All were alive and disease free at last follow-up, with a mean 133 months of follow-up. The principle differential diagnoses include fibrosarcoma, fibromatosis, pleomorphic adenoma, myoepithelioma, neurofibroma, schwannoma, solitary fibrous tumor, leiomyoma, fibrous histiocytoma and myxoma. NF of the parotid gland occurs in middle-aged patients who present with a mass (mean 2.2 cm) in the parotid gland of short duration (1.9 months). FNA misinterpretation frequently leads to excision. Separation from myoepithelial and mesenchymal lesions affecting the parotid gland results in appropriate management.
PMCID: PMC4542790  PMID: 25472697
Nodular fasciitis; Parotid; Salivary gland; Soft tissue; Differential diagnosis; Immunohistochemistry; Myofibroblasts
16.  Parotid gland lesions: separate and combined diagnostic value of conventional MRI, diffusion-weighted imaging and dynamic contrast-enhanced MRI 
The British Journal of Radiology  2016;89(1060):20150912.
To evaluate the ability of conventional MRI, diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) MRI to differentiate malignant and benign parotid lesions.
A retrospective review of MRI findings was performed in patients with pathologically confirmed parotid lesions between January 2010 and December 2014. Morphological MRI characteristics and functional characteristics such as apparent diffusion coefficient (ADC) and pattern of time–signal intensity curve (TIC) were recorded and compared. For each lesion, summed scores were respectively calculated for conventional MRI alone, conventional MRI with DWI and/or with DCE-MRI. Statistical analyses were performed to assess the association of these characteristics and summed scores with malignancy.
A total of 207 patients (111 males and 96 females; age: 48.4 ± 17.0 years) were included, consisting of 156 benign and 51 malignant tumours. After adjusting for age, sex, smoking status, alcohol use and tumour size, the lesions with ill-defined margin, adjacent tissue infiltration, cervical lymphadenopathy, ADC ≤1.01 × 10−3 mm2 s−1 and plateau TIC pattern are more likely to be malignant than those without these findings. Significant difference in receiver operator characteristic was detected after adding DWI to conventional MRI (p = 0.003), generating a sensitivity and specificity of 54.05% and 91.30%, respectively. Compared with lesions score <3, lesions with score ≥5 in the combination of conventional MRI and DWI were approximately 90 times more likely to be malignant parotid tumour. Additional DCE-MRI did not improve differential ability of conventional MRI.
Morphological and functional MRI characteristics are associated with malignancy in parotid gland. The diagnostic value of MRI would increase when DWI is applied in combination with conventional MRI.
Advances in knowledge:
The parotid lesions with ill-defined margin, adjacent tissue infiltration, cervical lymphadenopathy, ADC ≤1.01 × 10−3 mm2 s−1 and plateau TIC pattern are more likely to be malignant. The diagnostic value of conventional MRI would be increased when DWI is applied in combination, whereas additional DCE-MRI did not improve differential ability of conventional MRI.
PMCID: PMC4846216  PMID: 26892378
17.  Role of Fine-Needle Aspiration Cytology in Swellings of the Parotid Region 
The Indian Journal of Surgery  2010;73(1):19-23.
To report the role of preoperative fine-needle aspiration cytology (FNAC) in patients with swellings in the parotid region at a tertiary care center. Prospective study of FNAC results compared with final histologic diagnosis as the standard criterion. An academic tertiary care center. A consecutive series of 51 patients who underwent FNAC of swellings in the parotid region between 2007 and 2009, of whom 41 had surgical resection. Predictive value, sensitivity, specificity, and accuracy. FNAC was performed in all the 51 patients who presented with a swelling in the parotid region in the out patient department in our hospital. Sixteen patients (31.4 %) were diagnosed to have malignancy, thirty patients (58.8 %) were diagnosed as benign condition. The FNAC was not satisfactory in 5 patients (9.8%) even after repeated aspiration. The FNAC diagnosis of malignant or suspicious lesion of the parotid region had positive and negative predictive values of 90 % and 96.66%, respectively. The diagnostic accuracy of FNAC is 95 %. We strongly recommend FNAC as a safe and accurate and less expensive method for preoperative diagnosis of the swellings in the parotid region.
PMCID: PMC3077176  PMID: 22211032
Parotid swellings; Fine needle aspiration cytology
18.  Clinical Outcome of Parotidectomy with Reconstruction: Experience of a Regional Head and Neck Cancer Unit 
Salivary gland pathologies represent a histologically diverse group of benign and malignant neoplasms. Currently, World Health Organization recognizes 13 benign and 24 malignant variants of all salivary gland neoplasms. Surgery continues to remain the main-stay for treatment of parotid gland neoplasms. The aim of this study was to document our experiences of the patients treated for parotid tumors and find out if any compelling variable predicted the relative clinical outcomes.
Materials and Methods:
This was a retrospective study, from records of parotidectomies performed at the operating theatre by the head and neck cancer division of the study institution between 2010 and 2013. Eligibility for study inclusion included cases with benign or malignant parotid neoplasms requiring surgical management with or without adjunct radiotherapy. The predictors of postoperative complications, overall survival (OS), and disease-free survival (DFS) were analyzed.
A total of 20 patients underwent parotidectomy. The mean age was 42 years. Tumors were located on the left parotid in 13 cases (65%) and the right parotid in 7 cases (35%). The surgical procedures comprised 16 superficial parotidectomies, 1 total parotidectomy, and 3 radical parotidectomy (inclusive of facial nerve sacrifice) and 2 neck dissections levels II–V. The reconstructive procedures were 2 facial nerve branch cable grafts, 1 end-to-end facial-facial nerve branch anastomoses, and 2 facial re-animation surgeries (temporalis muscle suspensions). A total of five cases (33.3%) had postoperative complications. 2 variables (length of surgery and neck dissection) were found to have an impact on postoperative complications that were statistically significant. Additionally, length of surgery was a significant predictor on the 2 years OS and DFS.
The result of this study showed good clinical outcome, especially in the benign cases. The comprehensive clinical outcome of the malignant cases could not be objectively assessed, as the OS and DFS were 50% at 2-years follow-up. It is our submission that a larger sample size is utilized in subsequent studies and quality of life evaluation is included in the methodology.
PMCID: PMC4785688  PMID: 27013855
Facial re-animation; neural anastomosis; parotidectomy
19.  Diagnostic Accuracy of Fine Needle Aspiration Cytology in Parotid Lesions 
ISRN Surgery  2011;2011:721525.
Objective. Histopathology of parotid gland tumors is extremely varied and complex due to heterogeneous cellular composition. Preoperative diagnostic tools include fine needle aspiration cytology, the role of which remains controversial. The aim of this paper is to evaluate the usefulness and accuracy of fine needle aspiration cytology (FNAC) in the diagnosis of parotid gland tumors. Methods. We retrospectively reviewed charts of 129 patients who underwent parotidectomy for parotid lesions at Aga Khan University Hospital from 2002 to 2010. We compared the results of preoperative FNAC with final histopathological diagnosis. Results. Concordance with histological results was observed in 86%, specificity was 98%, sensitivity was 84%, and diagnostic accuracy was 94%. Conclusion. Our results demonstrate that preoperative cytology in parotid lesions is fairly accurate and useful in diagnosing benign from malignant and in planning appropriate approach for treatment.
PMCID: PMC3200214  PMID: 22084773
20.  Solitary Fibrous Tumor of the Parotid Gland: A Case Report 
Solitary fibrous tumor is a rare, mesenchymal neoplasm that has been reported in numerous sites. Occurrence in the parotid gland is exceedingly rare.
Case Report:
A 53-year-old man with a 2 cm solitary fibrous tumor of the left parotid gland, that was observed clinically and operatively and thought to be a neoplasm arising from Stensen's duct, is described. A pre-operative CT scan demonstrated a well-circumscribed, solid, avidly-enhancing nodule superficial to the masseter muscle, deep to the platysma, and intimately associated with the parotid duct. Multiple fine needle aspirations yielded scant fibrous tissue and lymphocytes. A superficial parotidectomy was performed. The histopathological and immunohistochemical findings were in keeping with solitary fibrous tumor, fibrous variant, with a low mitotic rate and a peripherally-entrapped parotid duct surrounded by abundant periductal collagen and lymphocytes. At a 2-year follow up, there was no evidence of tumor recurrence or metastasis.
Solitary fibrous tumor should be suspected in the context of a slow-growing, well-circumscribed, solid, avidly-enhancing nodule of the parotid gland. Grossly intimate association with the parotid duct may reflect peripheral entrapment. Fine needle aspirations that predominantly yield collagen without spindle cell clusters should be correlated with clinical and radiological findings, as it is expected in tumor sampling of the fibrous variant. Although solitary fibrous tumor of the parotid gland usually exhibits benign behavior, it is best regarded as potentially malignant. Patient management and follow-up should be tailored to each individual and clinicopathological risk assessment of the recurrent/metastatic potential.
PMCID: PMC4639695  PMID: 26568946
Parotid gland; Parotid diseases; Solitary fibrous tumors
21.  Differential Diagnosis of Parotid Gland Tumors: Role of Shear Wave Elastography 
BioMed Research International  2017;2017:9234672.
To create a predictive score for the discrimination between benign and malignant parotid tumors using elastographic parameters and to compare its sensitivity and specificity with standard ultrasound.
A total of 124 patients with parotid gland lesions for whom surgery was planned were examined using conventional ultrasound, Doppler examination, and shear wave elastography. Results of the examinations were compared with those ones of histology.
There were 96 benign and 28 malignant lesions in our cohort. Blurred tumor margin alone proved to be an excellent predictor of malignancy with the sensitivity of 79% and specificity of 97%. Enlarged cervical lymph nodes, tumor vascularisation, microcalcifications presence, homogeneous echogenicity, and bilateral occurrence also discriminated between benign and malignant tumors. However, their inclusion in a predictive model did not improve its performance. Elastographic parameters (the stiffness maxima and minima ratio being the best) also exhibited significant differences between benign and malignant tumors, but again, their inclusion did not significantly improve the predictive power of the blurred margin classifier.
Even though elastography satisfactorily distinguishes benign from malignant lesions on its own, it hardly provides any additional value in evaluation of biological character of parotid gland tumors when used as an adjunct to regular ultrasound examination.
PMCID: PMC5615951
22.  Usefulness of a Novel Ultrasonographic Classification Based on Anechoic Area Patterns for Differentiating Warthin Tumors from Pleomorphic Adenomas of the Parotid Gland 
Yonago Acta Medica  2018;60(4):220-226.
Ultrasonographic homogeneity is an important differential finding between Warthin tumor and pleomorphic adenoma, two types of benign parotid gland tumors, with the former likely to be heterogeneous and the latter homogeneous. However, differences in the performance of ultrasound machines or the homogeneity cut-off level affect the judgment of ultrasonographic homogeneity. Therefore, in this study, we adopted a novel system for classifying the composition of tumors via ultrasonography, using anechoic area as a substitute for differences in homogeneity to differentiate between Warthin tumors and pleomorphic adenomas.
We evaluated 68 tumors that were histopathologically diagnosed as Warthin tumor or pleomorphic adenoma between July 2009 and November 2015. Ultrasonographic images of the tumors were evaluated on the basis of key differentiating features, including features on B-mode imaging and color Doppler imaging. Additionally, the tumors were classified into four groups based on anechoic area, and findings were compared between Warthin tumors and pleomorphic adenomas.
While 38 of the tumors were pleomorphic adenomas, 30 were Warthin tumors. The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy for detection of Warthin tumors using our novel classification system were 73.3%, 76.3%, 71.0%, 78.4% and 75.0%, respectively. Compared to pleomorphic adenomas, Warthin tumors showed large or sponge-like anechoic areas, rich vascularization and an oval shape even at large tumor sizes, and the difference was significant. On defining Warthin tumor as a tumor demonstrating two or more of the findings noted above, the sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy for its detection were 73.3%, 84.2%, 78.6%, 80.0% and 79.4%, respectively.
Our novel classification system based on anechoic area patterns demonstrated by the tumors had high sensitivity, specificity and diagnostic accuracy for differentiating Warthin tumors from pleomorphic adenomas.
PMCID: PMC5803158
diagnostic imaging; parotid neoplasms; pleomorphic adenoma; ultrasonography; Warthin tumor
23.  Primary High-Grade Poorly Differentiated Angiosarcoma of an Intra-parotid Lymph Node 
Head and Neck Pathology  2015;10(2):225-228.
Head and neck angiosarcoma is an infrequent malignant vascular tumor most commonly found in the skin and soft tissue of the head and neck. Most head and neck angiosarcomas are metastatic to cervical lymph nodes from other primitive location. We describe herein a case of primary high-grade poorly differentiated angiosarcoma arising in an intra-parotid lymph node, discuss the value of immunohistochemical stains for differential diagnosis, and review the literature concerning head and neck angiosarcoma. A 47-year-old man presented with a painless mass that had grown for a period of 6 months in the parotid area. The CT-scan revealed a left parotid lesion of 17 mm. Fine needle aspiration was considered suspicious for lymphoma or poorly differentiated carcinoma. A superficial parotidectomy was performed. On gross examination, the lesion was a well-defined, gray, homogeneous mass of 15 mm of diameter. Microscopic examination showed a normal parotid tissue and a poorly differentiated malignant neoplasm in an intra-parotid lymph node. The tumor had a pseudo-alveolar pattern, with large pleomorphic epithelioid cells, abundant eosinophilic cytoplasm, large vesicular nuclei, and one or more prominent nucleoli. Atypical mitoses were seen. Neoplastic malignant cells stained positive for Vimentin, CD31, D2-40, factor VIII, ERG, and partially for CD34. A positron emission tomography scan was made to search for a primary neoplasia, but no other tumor was localized. The diagnosis of primary high-grade, poorly differentiated, intra-parotid lymph node angiosarcoma was established.
PMCID: PMC4838960  PMID: 25930154
Primary angiosarcoma; Poorly differentiated angiosarcoma; Lymph node tumour; Markers of vascular tumors
24.  Distinguishing benign from malignant parotid gland tumours: low-dose multi-phasic CT protocol with 5-minute delay 
European Radiology  2011;21(8):1692-1698.
To explore the percentage enhancement wash-out ratio (PEW) and relative PEW (RPEW) of low-dose multi-phasic computed tomography (CT) in distinguishing benign from malignant parotid gland tumours.
This study was approved by the ethics committee, and informed patient consent was obtained. 51 patients with parotid tumours proven by histopathology received CT, including 18 with pleomorphic adenomas, 14 with Warthin’s tumours and 19 with malignant tumours. Size and attenuation of parotid tumours were measured. Compared with 5-min attenuation, the 30-s and 90-s PEW (PEW30, PEW90) and RPEW (RPEW30, RPEW90) were calculated.
There was a significant difference in PEW30, RPEW30, PEW90 and RPEW90 in the parotid neoplasms groups (P < 0.01), and statistical significance existed simultaneously in pleomorphic adenomas vs malignant tumours and Warthin’s tumours vs malignant tumours according to SNK-q test. The optimal diagnosis results of malignancy with 100% specificity (32/32) was obtained by using a combination of the following criteria: −70% > PEW30 < 36%, −30% > PEW30 < 19%, PEW90 > 12%, and the sensitivity (74%) for diagnosis of malignancy was yield.
Wash-out ratio may assist in differentiating the benign from malignant parotid gland tumours. Combining the percentage of enhanced wash-out ratios of CT protocols can yield diagnostic results for malignancy.
PMCID: PMC3128264  PMID: 21547526
Low-dose CT·parotid gland neoplasm; Dynamic contrast-enhanced CT; Percentage enhancement wash-out ratio
25.  Diagnostic value of CT perfusion imaging for parotid neoplasms 
Dentomaxillofacial Radiology  2013;43(1):20130237.
To assess the value of CT perfusion imaging in the differentiation of different histological categorization of benign tumours from malignant tumours in patients with parotid neoplasms.
CT perfusion was successfully performed in 62 patients with parotid neoplasms whose diagnoses were confirmed by surgery or biopsy. The software generated a tissue time–density curve (TDC) and measured blood volume, blood flow, mean transit time and capillary permeability surface product. One-way ANOVA and receiver operating characteristic curves were used to analyse the difference and diagnostic efficacies of all perfusion data between each one of the benign tumours and malignancies. Statistical significance was assigned at the 5% level.
Pleomorphic adenomas mainly had a gradually ascending TDC. Warthin tumours showed a fast ascent followed by a fast descent. The TDC of basal cell adenomas had a fast ascension followed by a plateau, then a gradual descent. Malignant tumours mainly showed a rapidly ascending curve with a stable plateau. Significant differences were observed in blood flow, blood volume and mean transit time between pleomorphic adenomas and malignant tumours (p < 0.05) as well as in blood flow and blood volume between the Warthin tumours, the basal cell adenomas and the malignant tumours (p < 0.05). Differences in permeability surface between the basal cell adenomas and malignant tumours were significant (p < 0.01).
CT perfusion of parotid gland could provide TDC and perfusion data, which were useful in the differentiation of different histological benign tumours and malignant tumours in the parotid gland.
PMCID: PMC3887482  PMID: 24186883
parotid gland; neoplasms; computed tomography; perfusion

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