Characterisation of adenoid cystic carcinoma of the breast by immunohistology.

Abstract

SUMMARY An adenoid cystic carcinoma of the breast in a 78 year old woman was analysed immunohistologically for the production of type IV collagen, the expression of vimentin, epithelial membrane antigen (EMA) and steroid receptors, and the proliferative activity of the tumour cells. The data were compared with those obtained in eight adenoid cystic carcinomas of salivary glands and in ductal carcinomas of the breast with a cribriform growth pattern. The patients' ages were as follows: 45-80 years (mean 63 2) for the salivary gland carcinomas; 37-69 years (mean 50 6) for the ductal breast carcinomas. In contrast to the cribriform spaces of ductal carcinomas, the pseudocysts in adenoid cystic carcinomas were lined by type IV collagen. The opposite pattern was observed for EMA. Like the myoepithelium of normal breast, the myoepithelium-like cells of adenoid cystic carcinoma stained positive for vimentin while the ductular epithelium-like ones did not. All adenoid cystic carcinomas, including that of the breast, were negative for the oestrogen and progesterone receptors, unlike the ductal carcinomas. Proliferative activity of the adenoid cystic carcinoma of the breast was relatively low.These data broaden the range ofantibodies suitable for differential diagnosis of both tumour types.

KIT is highly expressed in adenoid cystic carcinoma of the breast, a basal-like carcinoma associated with a favorable outcome

“…By classifying breast cell populations according to the system proposed by Bocker, 36 we identified four distinct types of cells in adenoid cystic carcinoma of the breast; rare CK5/6 þ cells (CK8/18À/p63À) or progenitor cells, CK5/6 þ /CK8/18 þ cells (/p63À) or glandular precursor cells, CK8/18 þ cells Although the origin of adenoid cystic carcinoma of the breast is still debated, it seems to be widely accepted that this tumor is derived from undifferentiated cells, which have the capacity to differentiate towards ductal and myoepithelial cells. 9,10,25,37 Our study confirmed this theory, as we demonstrated the presence of CK5/6 þ cells that could represent precursor cells. However, even by using a double immunostaining procedure, we were unable to identify a CK5/6 þ /P63 þ population of cells which could correspond to myoepithelial precursor cells.…”

“…Nonsentinel axillary lymph node dissection was performed in Adenoid cystic carcinoma of the breast S Azoulay et al eight cases. The median number of lymph nodes examined was 12 (range: [7][8][9][10][11][12][13][14][15][16][17][18][19]. No lymph node metastases were seen in either of these cases.…”

“…Immunohistochemical studies have shown that adenoid cystic carcinoma of the breast are estrogen receptor (ER)-negative tumors composed of a double population of cells: epithelial cytokeratin-positive cells, and myoepithelial, vimentin and S100 protein-positive cells. [7][8][9][10] Recent descriptions have identified two distinct molecular weight cytokeratins (CK) as markers of different population of breast gland epithelium; CK8/18 (low molecular weight CK) expressed by luminal cells and CK5/6 (high molecular weight CK) expressed by basal cells. 11 Stem cells, which have the capacity to differentiate towards either glandular or basal phenotype, have also been identified.…”

Carcinomas of the breast showing myoepithelial cell differentiation

“…3) but not the ductule-like structures [14]. EMA and high-molecular-weight keratin antibodies stain the larger cells lining the ductule-like structures [57], while these same antibodies are negative in the basaloid elements [14]. Immunohistochemistry with anti smooth muscle actin antibody reveals a third cell type.…”

“…PAS staining and anti-collagen IV immunostaining reveal a thick basal lamina bordering the cribriform and the microcystic structures ( Fig. 3) but not the ductule-like structures [14]. EMA and high-molecular-weight keratin antibodies stain the larger cells lining the ductule-like structures [57], while these same antibodies are negative in the basaloid elements [14].…”