Objective: Primary neuroendocrine carcinoma of the breast
(NECB) is a rare distinct type of breast carcinoma. There is limited
data about the optimal management, treatment, and prognosis.
Therefore, we analyzed the clinicopathological features, management and the clinical outcome of this rare breast carcinoma.
Material and Methods: Patients diagnosed as NECB between
July 2008 and January 2018 were included in the study. Medical
records were retrospectively reviewed.
Results: A total of 4,896 breast cancer patients were reviewed
and 18 NECB (0.4% of all cases) were extracted. The median
age was 61.5 (30-82). Thirteen cases (72.2%) underwent breast
conserving surgery. Eight patients had axillary lymph dissection.
All of the cases were pathological T1 and T2. Only one patient
was pathological stage 3. Median tumor size was 20.5mm (10-
45). Only two cases presented with small cell subtype, the rest
were well-differentiated. Hormone receptor was positive and
HER2/neu was negative for all cases. Of the 15 patients with
known Ki-67, three had high expressions (≥20%). No local or
distant disease recurrences and death related with NECB were
detected at a median follow-up period of 101 months (33-148).
Conclusion: NECB is more likely to be hormone receptor positive
and HER2/neu negative as luminal A or B subtype. An excellent
clinical outcome is remarkable despite a substantial number of patients with axillary lymph node positivity specifically for well-differentiated subtype. Less invasive treatment options should be kept
Keywords: Neuroendocrine carcinoma, breast neoplasm,