Pleomorphic lobular carcinoma of the breast - a diagnostic dilemma

Abstract

Pleomorphic lobular carcinoma of the breast has been identified as a histological variant of infiltrating lobular carcinoma (ILC) with poor prognosis. Thus, cytological recognition of this tumour is important. It is characterized by pleomorphism to a degree that contrasts with the cytologic uniformity of classic ILC. Due to this feature it is often misinterpreted as infiltrating ductal carcinoma and diagnosed only on appreciating the Indian file and targetoid pattern of lobular carcinomas on histology. We report three cases with this unusual tumour that can present a diagnostic dilemma on cytology.

The value of systematic pattern analysis in FNAC of breast lesions: 225 cases with cytohistological correlation

“…However, a higher proportion of dissociated cells, homogenous small malignant cells with minimal cytoplasm, large but non-pleomorphic nuclei are pointers for classic form of invasive lobular carcinoma. [ 21 22 ]…”

p53 mutations in classic and pleomorphic invasive lobular carcinoma of the breast

“…Within ILC, several subtypes can be discerned: 1) the classic type composed of small regular cells with frequently intracytoplasmic vacuoles, small nuclei and a typical trabecular infiltration pattern with dissociated cells or forming single files, often in targetoid patterns around uninvolved ducts and with low mitotic rate; 2) the better demarcated alveolar type exhibiting small round aggregates of 20 or more cells with typical lobular cytology; 3) the also better demarcated solid variant consisting of more solid sheets of cells with little intervening stroma, more mitoses and often some more atypia; 4) the pleomorphic variant that exhibits the growth pattern of classical lobular carcinoma throughout but with polygonal, eccentric pleomorphic nuclei and more frequent mitoses [ 6 ]. The pleomorphic variant of ILC (PILC) accounts for less than 1% of all breast carcinomas and not more than 10% of all ILC [ 7 ]. It has a poorer prognosis compared to classic ILC [ 5 , 8 ].…”

Pleomorphic variant of lobular carcinoma breast: A rare case report with review of the literature

“…Since grading of lobular carcinoma is intricate identification of the pleomorphic subtype is useful in identifying a lethal variant. [11] Its behavior is assessed on the basis of the tumor size at presentation and the occurrence of nodal metastases. It is important to diagnose PLC, as ILCs in general, are more often multifocal and bilateral.…”