Other rare variants of Breast Carcinoma

Apocrine carcinoma
Apocrine carcinoma is a morphologic variant of ductal carcinoma. FNA smears contain numerous epithelial cells arranged in syncytial fragments along with individually scattered cells. The cells show apocrine features, consisting of abundant basophilic to eosinophilic granular cytoplasm and large nuclei with prominent nucleoli. It can be difficult to differentiate from atypical apocrine metaplasia.

Secretory carcinoma
Smears of this rare variant of breast carcinoma consist of large irregular sheets of malignant polygonal cells with granular to vacuolated cytoplasm. The presence of grape-like clusters of vacuolated cells is a helpful diagnostic feature.

Squamous cell carcinoma
Pure squamous cell carcinoma is very rare in the breast, although a malignant squamous component may occasionally be present in ductal carcinoma. FNA smears show well to poorly differentiated malignant squamous cells, with cytoplasmic keratinisation and intercellular bridges. The cells are arranged in sheets or syncytial groupings or scattered individually.

Intracystic carcinoma
This is a very rare variant of breast carcinoma, resulting in a cystic mass which usually persists after aspiration of a typically haemorragic fluid. Cytological smears are poorly cellular, with mildly atypical cells arranged in loosely cohesive groups and papillary clusters.