Institutional Spectrum of Rare Histological Types of Breast Carcinoma

Abstract

Background: Invasive breast cancer is a heterogeneous disease in its presentation, pathological classification and clinical course. Most tumors are derived from mammary ductal epithelium, principally the terminal duct-lobular unit. However, there are more than a dozen histological variants which are less common but still very well defined by the World Health Organization (WHO) classification. The prime objective of the current study is to document our institutional experience of such rare histological entities with review of literature of the same. Methods: The clinicopathological records of resected breast lesions submitted to histopathology department over the period of three years from Jan 2016 to December 2018 were reviewed retrospectively. It was observational, retrospective and descriptive analysis of 4 unusual histological types of breast carcinoma. The most common lesions like infiltrating ductal carcinoma (IDC) and infiltrating lobular carcinoma in malignant category and benign lesions were excluded from the study. Results: Among 528 breast malignancies reported in the institute, 48 unusual histological types were recognized, of which 4 are very rare histological types with less than 1% incidence. Conclusions: Here in we highlighted the rare varieties of cribriform, squamous, apocrine and signet ring cell carcinoma of breast with relevance to clinical, histopathological and immunohistochemical features. It is with significance to the fact that histological diversity of breast carcinoma has relevant prognostic implications.