Clinicopathological Characteristics and Outcomes of Metaplastic Breast Cancer: Experience from a Tertiary Cancer Center in India

Abstract Metaplastic breast carcinoma (MBC) is a rare heterogeneous subtype of breast cancer, with limited data. Currently, it is treated according to the invasive breast cancer consensus guidelines, but it has a more distinct, aggressive biology and needs a more specific management. Our study aimed to evaluate the clinicopathological features, treatment response, and survival outcomes of our MBC patients treated with standard treatment modalities. We retrospectively analyzed clinicopathological characteristics, treatment, and survival outcomes of 20 patients diagnosed with MBC between 2012 and 2025. Twenty MBC patients were analyzed. The median age of presentation was 59.5 years. Fifty percent of patients had a clinical T3 tumor. Twenty percent had axillary lymph node involvement. Preoperative core biopsy was MBC in 40%. Most patients underwent mastectomy, and five patients underwent breast conservation surgery. Seventy-five percent had triple-negative receptor status. Of the 35% patients who received neoadjuvant chemotherapy (NACT), only one patient had a complete response. Adjuvant radiation was administered to 65%. Twenty percent received hormone therapy, and 5% received HER2-targeted therapy. At a median follow-up of 13.5 months (range: 3–72 months), 12 patients (60%) were alive with no evidence of disease, and eight patients (40%) died. Tumor recurrence was seen in five patients (25%). Overall survival (OS) at 1, 3, and 5 years was 84.4, 65.1, and 48.8%. Median OS was 55.2 ± 21.8 months. Recurrence-free survival was 64.7 ± 15.8 months. Statistically significant variable worsening the OS on univariate analysis was NACT (HR: 6.13, 95% CI: 1.09–34.46, p = 0.040). However, none of the variables were statistically significant by multivariate analysis. MBC is a rare and pathologically challenging diagnosis at core biopsy. Despite the large size at presentation, initial surgery should be preferred whenever feasible. Though lymph node metastasis is rare, when present, it has a worse prognosis.