|Home | About | Journals | Submit | Contact Us | Français|
Adenoid cystic carcinoma (ACC) of the breast is a rare neoplasm accounting for 0.1% of breast carcinomas.
A 30 year old female patient presented with multiple lumps in the right breast. Excision biopsy of a lump in the lower outer quadrant revealed adenoid cystic carcinoma. A right sided modified radical mastectomy (MRM) was performed, with axillary clearance. Histopathology revealed a fibroadenoma accounting for one mass and adenoid cystic carcinoma in another, confirmed on Periodic acid Schiff (PAS) staining. Three out of the eight excised axillary lymph nodes contained malignancy. There was no evidence of recurrence or distant spread at follow-up 6 months postoperatively.
ACC of the breast is a rare neoplasm accounting for 0.1% of breast carcinomas and is of special interest because of its favourable prognosis and distinctive histological appearance. This tumor occurs predominantly in women in their sixth decade and usually presents as a tender breast mass, often in the subareolar area though in our case it was not tender and presented as multiple lumps in the right breast. The diagnosis can be made on fine needle aspiration cytology (FNAC), but in our case FNAC was inconclusive. We performed MRM with axillary clearance, and three out eight lymph nodes proved positive for malignancy.
ACC is a rare malignant neoplasm. Surgical treatment is the mainstay with little role for radiotherapy and chemotherapy according to the published literature.
Adenoid cystic carcinoma (ACC) of the breast is a rare breast cancer variant and optimal management is unclear. Salivary gland tumors having the same histological pattern as ACC of the breast were first termed “cylindroma” by Billroth. Although ACC of the breast can occur between 30 and 90 years of age, it is more common in women in their fifth or sixth decade. Most patients present with a dominant breast mass tender to palpation. Histologically, ACC has a unique distinctive biphasic pattern that consists of true laminate and pseudocystic spaces; true glands are lined by epithelial cells and pseudocysts are lined by myoepithelial cells. Cytologically, the tumor shows a typical pattern: globules of mucus surrounded by epithelial cells with little cytoplasm and small hyperchromatic nuclei. It is generally estrogen receptor (ER) and progesterone receptor (PR) negative. ACC reportedly has a better prognosis than most forms of breast cancer and the incidence of axillary lymph node metastases is lower. Distant metastases are uncommon, but when they occur they tend to do so without prior lymph node involvement.
A 30 year old female presented to the outpatient department with multiple lumps in the right breast for six months. There was no past history of breast surgery or breast irradiation. On examination three painless, freely mobile lumps were palpable, up to 3 cm in maximal diameter, making the right breast larger than the left. The skin of both breasts was normal. Right sided axillary lymph nodes were palpable. Mammography suggestive of right breast as multiple, irregular, hyperdense mass lesion diffusely present in the breast, largest measuring approximately 24 × 16 mm with irregular speculated margins causing distortion of adjacent parenchyma. No calcification, suggestive of neopastic lesion. Ultrasonography suggestive of multiple round to oval mass in right breast largest measuring about 3 × 1.5 cm possibility of malignant lesion. All routine blood investigations and a chest X-ray were within normal limits. Fine needle aspiration cytology of one mass revealed a fibroadenoma. Excision biopsy of another right breast lump was diagnosed as adenoid cystic carcinoma (Figs. 1 and 2). Right modified radical mastectomy with axillary lymph node dissection was performed and histopathology was consistent with residual ACC (confirmed on PAS staining), with the surgical margins free from malignant cells. Three out of eight lymph nodes tested positive. Involved lymph nodes revealed same features as that of the main tumor (Fig. 3) (microphotograph of the lymph node is provided) and no evidence of ductal carcinoma.
ACC of the breast is a rare neoplasm accounting for 0.1% of breast carcinomas.1 It is of special interest because of its favourable prognosis and distinctive histological appearance.2 This tumor occurs predominantly in women in their sixth decade but has been described between the ages of 30 and 90. It is rarely bilateral and has no predilection for a particular side.3 ACC most frequently presents as a tender breast mass, often in the subareolar area. The prognosis is more favourable than for other types of breast cancer as lymph node involvement and distant metastasis are rare,4 nor does it show the aggression characteristic of adenoid cystic carcinoma of the salivary gland, in which pain and tenderness are attributed to perineural invasion by the tumor. Although ACC of the breast is most commonly subareolar, nipple discharge is an uncommon presenting symptom.5 The diagnosis can be made on fine needle aspiration cytology.6,7 Histopathologically, there are well formed islands of cohesive cells and regular small, sharply defined spaces. These islands have multiple microcystic spaces containing PAS-positive mucinous material8 with an acidic pH (true epithelial mucin has a neutral pH). The histological appearance of ACC and invasive cribriform carcinoma are similar.9 Confirmation of the diagnosis can be obtained by Alcian blue staining, PAS staining and immunohistochemistry: the cysts stain with Alcian blue and the ducts stain with PAS.10 Ro classified ACC into three grades of tumor on the basis of the solid component as: grade 1, completely glandular and cystic; grade 2, <30% solid component; grade 3, >30% of solid components. All grade 3 tumors appear to behave like high grade ductal breast cancer.11 Most such tumors have negative ER-PR status.12 The various options for treatment include lumpectomy, wide excision with or without radical radiation, or modified radical mastectomy. Axillary lymph node dissection is rarely required because of the low incidence of spread to the axillary lymph nodes, which makes our case extremely unusual (Table 1).
ACC is rare neoplasm and surgery is main stay of treatment. Neither adjuvant chemotherapy nor hormonal manipulation has been studied in patients with ACC of the breast. No conclusions have been drawn regarding radiation and chemotherapy. Since it is a rare neoplasm clinical trials comparing treatment options for ACC are needed to define the optimal treatment.
There is no conflict of interest.
Written informed consent was obtained from the patient for publication of this case report and accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal on request.
All authors contributed equally.
We thank Mrs Deshingkar for secretarial help.