Due to widespread use of radiological studies, cystic pancreatic tumor cases are increasing. The diagnosis of malignancy in cystic pancreatic tumor cases requires pancreatic resection. Little information is presently available on the incidence and behavior of PC. Clinical and laboratory features of cystic pancreatic lesions may predict underlying malignancy.[6
Many studies reported that SCAs occurred in patients with a median age around 50 years.[9
] Solid and cystic papillary tumors as well as simple cysts have generally been reported in younger patients.[6
] Benign mucinous cystic neoplasm have a median age around 50 to 55 years, whereas mucinous cystadenocarcinoma generally have a median age of 60 to 65 years.[8
] In our study, patients with malignant cysts were older than patients with benign cysts with statistical significance (the median age was 40 years in patients with benign cysts, compared with 64 years in patients with malignant cyst, P
= 0.0001); thus, older patients are more likely to have premalignant or malignant cystic pancreatic neoplasms.
The majority of cystic neoplasms in our study occurred in women. The overall incidence of malignancy was higher in men (18/53; 34% in benign group vs 16/28; 57.1% in malignant group; P
= 0.004). The majority of patients with mucinous cystadenoma were females, 65.2% in SCA, 100% in SPT, and 42.9% in malignant cyst. Prevalence of cystic neoplasms in female patients has been observed in other studies as well.[8
] Lee et al
] reported that the overall incidence of malignancy was significantly higher in men, 14 of 67 (28%), compared to women, 12 of 99 (12%) (P
< 0.02). Thus, male gender may suggest malignant behavior of PC.
In this study, 60 patients had one or more symptoms including abdominal pain, jaundice, weight loss, nausea, vomiting, and mass. However, 21 patients were asymptomatic. Asymptomatic patients were more in the benign group than in the malignant group (35.8% vs 7.1%, respectively; P
= 0.005). Symptoms of abdominal pain and weight loss had a significant association with malignant tumors. Fernandez-del Castillo et al
] found that 134 of their 212 patients (63%) with PC were symptomatic. Malignant lesions were found in 40% of their symptomatic patients compared with only 17% of their asymptomatic patients (P
= 0.001). Lee et al
] reported that the presence of one or more symptoms was a significant predictor of malignant pathology. Symptoms of jaundice, weight loss, and anorexia had associations with malignant tumors. Moesinger et al
] found that less than half of their patients with SCAs and benign mucinous cystic tumors had symptoms, whereas 80% to 85% of their patients with mucinous cystadenocarcinoma were symptomatic. Spinelli et al
] reported that the presence of symptoms predicted premalignant or malignant pathology. Javle et al
] found that palpable abdominal mass on presentation was significantly more in the malignant group (4/17 patients) than in the benign group (0/18 patients). Weight loss occurred more in the malignant group (7/17 patients) than in the benign group (2/18 patients) with statistical significance.
Several studies correlating size and malignancy risk have revealed that smaller cystic neoplasms are less likely to be malignant.[6
] In our study, the maximum cyst diameter was significantly greater (P
= 0.008) in the malignant cysts (6.5 ± 2.5 cm) as compared with the benign group (3.7 ± 1.4 cm). Five of 34 (14.7%) patients with cystic pancreatic lesions < 3 cm had malignant tumor. Spinelli et al
] reported that cyst size did not correlate with final pathology. Sarr et al
. found no difference in the mean size of benign mucinous cystadenoma and mucinous cystadenocarcinoma.[15
] On the other hand, Chari et al
. found that their 73 noninvasive IPMN was 5.2 cm in diameter, whereas their 40 invasive IPMN was 6.6 cm.[21
] Lee et al
] reported that 31 of 166 (19%) patients with cystic pancreatic tumors < 3 cm had malignancy, which is in accordance with the results of other series that report malignancy rates ranging between 13 and 20% in small lesions.[23
] Thus, cysts of small size do not exclude its malignant potential but malignancy is more with larger cyst size.
In our study, cyst location did not predict malignant behavior of the cyst. In some studies, the mucinous types of PC arise from the duct epithelium, are often large (sometimes >10 cm), and usually located in pancreatic body or tail; SCAs are smaller (<2 cm), and often seen on head of the pancreas[8
] and conversely, mucinous cystadenocarcinoma have a tendency to occur more often in the head of the pancreas.[6
Many studies have reported the presence of solid component inside the cyst to be a significant predictor of malignancy.[22
] In our study, the most significant radiological findings associated with malignancy were the presence of a solid component (P
= 0.0001), loculation (P
= 0.001), and wall thickening (0.0001). Both the presence of solid component and wall thickening were found to be independent predictors when considered in a multivariate analysis.
Endoscopic US with fine needle aspiration has been suggested as a diagnostic tool to differentiate between benign and malignant cysts. However, aspiration by the needle has the potential to spill malignant cells with possibility of reducing survival.[6
] For this risk, as well as the accuracy of fluid analysis, several studies[6
] and as also in our study, did routinely use endoscopic US which is expensive, invasive, and needs experience. Recently, positron emission tomography has been found to be accurate in detecting small pancreatic cancers, but it is very expensive.[27
The management of pancreatic cystic lesions remains controversial. Although an aggressive resectional approach is advocated by some,[28
] an increasing number of clinicians are now questioning the practicality of this strategy with the marked increase in the incidence of PC detected incidentally on radiologic imaging.[26
In the absence of randomized controlled data to guide treatment recommendation, the International Association of Pancreatology identified several factors as indication for resection of PC IPMNs. These include diameter > 3 cm, any solid component, and the presence of symptoms attributable to the cyst.[30
] However, any lesion thought to be MCN should be resected. SCA should be resected only if symptomatic, or if the diagnosis remains doubtful.[32
] Malignant SPT can be cured when completely excised, and prolonged survival can be seen even in the presence of metastatic disease. Management of PCN is based upon a balance of malignant potential and risk of surgical resection.[32
In our study, major pancreatic resection was recommended for symptomatic cysts, large lesions and for cysts that have potential malignancy or are malignant. Spinelli et al
] reported that majority of benign lesions are SCAs as well as solid and cystic papillary tumors. These benign tumors frequently can become large and symptomatic; eventually need a major pancreatectomy, whereas early management might allow limited resection. Similarly, early surgery in patients with mucinous cystadenoma, cystic neuroendocrine tumor, and benign IPMN will prevent malignant transformation and is likely to be more cost-effective than observation. James M. Kiely et al
] reported that for small cystic tumors in the uncinate, head, neck, and body of the pancreas, enucleation has advantages over pancreatic resection as regards to operative time, blood loss, and preservation of pancreatic parenchyma. Because the pancreas is otherwise normal in these patients, the risk of pancreatic leakage is high.
Allen et al
] have recommended follow up by high-quality CT or MRCP every year for asymptomatic cysts smaller than 2.5 cm. Also, Fernandez-del Castillo and Warshaw[2
] have recommended periodic imaging for small, asymptomatic PC. They recommend resection for larger cysts in young and middle-aged patients and cyst fluid aspiration for analysis for older patients.