Adenoid cystic carcinoma of the breast: case report and review of treatment options

Case Report

A 69-year-old postmenopausal woman was referred to our hospital with a lesion in her left breast classified as BIRADS IV. She had no family history of ovarian or breast cancer and never took hormone replacement therapy. She presented with a palpable tumour of 6cm in size in the lateral inferior quadrant of her left breast. A biopsy was taken with the diagnosis of adenoid cystic carcinoma (ACC) Grade II. A MR mammogram showed a tumour measuring 5,8×5x5cm. All investigations for secondary disease were negative.

She underwent a modified radical mastectomy with sentinel lymph node biopsy because of tumour size with the final diagnosis of ACC Grade II, pT3 (>5cm) pN0 M0 R0. Receptor status for Her-2/neu, oestrogen and progesterone were negative. Apart from the characteristic cylindromatous component, histological assessment revealed an unusual stromal differentiation with partially necrotic adipose tissue and focal myofibroblastic proliferation.

Decision was made for radiotherapy and chemotherapy was suggested because of a tumour size larger than 3cm. The patient declined chemotherapy and commenced radiotherapy six weeks postoperatively.

Discussion: ACC was first described by C.F. Geschickter in 1945. It usually arises from salivary glands and is a very uncommon diagnosis in the breast accounting for only 0,1% of all breast neoplasms. It occurs mostly in postmenopausal women and usually presents as a palpable, firm mass centrally or in the subareolar part of the breast. It has no predilection to develop bilaterally. Data on hormone receptor status show that only 46% are oestrogen and 35% are progesterone positive. The prognosis of ACC is generally good. Lymph node involvement is rare (4%). The 5 year overall survival rate is 85% and 10-year overall survival rate is 75%.

Looking at previously published case reports and literature we tried to identify the appropriate treatment for our patient. Mastectomy has been curative in virtually all cases, especially when axillary lymph nodes were negative. Postoperative radiotherapy seems to be beneficial if there is axillary lymph node involvement, following lumpectomy or in tumours with a solid component or invasive growth that are more likely to have recurrences (Grade II and III). Adjuvant chemotherapy may be considered in patients with high grade lesions (grade III) or if the tumour is larger than 3cm.