Clinical features of metaplastic breast carcinoma: A single-center experience

Metaplastic breast cancer (MBC) is a rare subtype with unusual clinical features. We aimed to analyze treatment results and define patients' characteristic features in our large MBC patient series.

Fifty-six patients with early MBC who received adjuvant radiotherapy (RT) in our center were included in the study. The age, sex, subtypes of MBC, histopathology, hormone and nodal status, tumor size, and types of treatment were retrospectively provided from hospital records.

The median tumor size was 4 (1.3-16.5) cm, and triple-negative MBC cases were 38 (67.8%) of all patients. Axillary nodal involvements were present in 25 (44.6%) patients. The median follow-up time was 45.8 (4.9-130) months; the overall survival (OS) and disease-free survival (DFS) for 5 years were 67% and 64%, respectively. While distant metastases were seen in 15 (26.7%) patients, local recurrences were seen in only 4 patients. The median OS and DFS were higher in patients with ≤5.2 cm tumor than >5.2 cm ([130 vs. 49 months, P = 0.01] and [130 vs. 30 months, P = 0.009], respectively). Nodal involvement, hormone receptor status, surgical treatment, and type of RT had no effect on survival. In multivariate analysis, tumor size was not an independent prognostic factor for OS (P = 0.068; hazard ratio [HR]: 3.4, 95% confidence interval [CI] = 0.91-12.8), whereas age >65 years was found an independent poor prognostic factor for OS ([HR: 4.25, 95% CI: 0.23-0.78, P = 0.021] and DFS [HR: 3.1, 95% CI: 0.02-0. 87; P = 0.04], respectively).

Distant metastasis is at the forefront rather than local recurrence in MBC patients. More studies are needed to determine the factors that affect survival independently in MBC.