Clinicopathologic Features of Metaplastic Breast Carcinoma: Experience from A Cancer Research Centre in India

Metaplastic Breast Carcinoma (MpBC) is a rare, aggressive form of breast cancer, comprising 1.4-5% of all breast malignancies. Typically classified as Triple Negative Breast Cancer (TNBC), MpBC behaves more aggressively than most TNBC cases, often presenting with worse outcomes despite node-negative stages. Given its rarity, knowledge is scarce regarding its natural history and optimum treatment. This study aims to evaluate the clinicopathological characteristics, therapeutic responses, and outcomes of MpBC patients at a tertiary cancer center in India. This retrospective study included MpBC patients treated at our institution from January 2016 to May 2023. Data collected included epidemiological, clinical, histopathological records and survival outcomes. Kaplan-Meier survival analysis was conducted using IBM SPSS ver 25. A total of 37 MpBC cases were identified. The median age at presentation was 51 years, with metastatic disease being more common in older patients. Most cases presented at Stage II (54.1%), average tumor size of 5.1 cm. Node-positive disease was found in 40.5% of patients. Surprisingly only 56.8% of patients had TNBC. The most common histological subtype was MpBC with squamous cell component (29.3%). The median overall survival was 56 months for the study cohort. MpBC is a rare and aggressive breast cancer subtype, often diagnosed post-surgery. Despite presenting with large tumors, it shows paradoxically low lymph node metastasis. Surgical management is the primary treatment, with chemotherapy showing limited efficacy.

The online version contains supplementary material available at 10.1007/s13193-025-02525-z.