To investigate the clinicopathology, management and prognosis of breast carcinoma with medullary features.

The clinicopathological data of 23 patients with breast carcinoma with medullary features in Second People’s Hospital of Changzhou City from January 2008 to January 2018 were retrospectively analyzed.

Twenty-three patients were histopathologically diagnosed with breast carcinoma with medullary features, accounting for 5.0% of all 463 invasive breast cancer patients in the same period. They were female, at the age of 32-67 years (median 50 years). There were 13(56.5%) cases of medullary breast carcinoma (MBC), 5(21.7%)atypical MBC and 5 (21.7%) non-specific invasive carcinoma with medullary features. The morphological characteristics of all 23 patients were similar. The tumor diameter was 1-5 cm and the tumor was nodular. The border of the tumor was clear in 20 cases, and unclear in 3 cases. The tumor was cystic in 2 cases and solid in other 21 cases. The MBC had a expansible margin and clear border; tumor cells were in a syncytial cell growth mode, and the intercellular border was unclear; the nucleus was round and vacuolated, with obvious abnormity; the tumor lacked stromal components, with significant lymphocyte infiltration peripherally. The atypical MBC and non-specific invasive carcinoma with medullary features were in a syncytial cell growth mode, with unclear border, invasive margin, glandular structure and a large number of lymphocytes infiltrated in the stroma. The positive rate of axillary lymph nodes was 30.4%(7/23). In immunohistochemistry, the positive rate of ER, PR, HER-2, EGFR and CK5/6 was 4.3%(1/23), 4.3%(1/23), 13.0%(3/23), 43.5%(10/23), 26.1%(6/23), respectively. Ki67 proliferation index was 20%-98%. All 23 patients were treated with surgery and adjuvant chemotherapy. Local radiotherapy was given in two cases, endocrine therapy in one case and targeted therapy (trastuzumab) in one case. All patients were followed up for 6-96 months (median 58 months). Four cases were missed during the follow-up. No recurrence and metastasis were found in other nineteen patients.

The breast carcinoma with medullary features is mostly triple-negative, with low clinical incidence. In spite of advanced staging based on cell morphology, it has low malignancy and good prognosis, usually treated by surgery combined with adjuvant chemotherapy.