Malignant breast myoepithelioma: A systematic review

We performed a systematic review in order to describe the clinical presentation, therapeutic management and outcomes of malignant myoepitelioma of the breast.

A systematic search of MEDLINE and EMBASE references from January 1980 to Marsh 2020 was performed. We included articles that reported cases of malignant breast myoepithelioma. Data from eligible studies were independently extracted onto standardized forms by two reviewers.

31 articles including 47 cases of malignant breast myoepithelioma and 3 other unpublished cases managed in our establishment were included in this systematic review. The average age at diagnosis was 60.7 years old [range 30-81]. The average size of the tumor was 46mm [range 10 -230]. 30 patients had a partial mastectomy and 18 a total mastectomy. Only 15% of patient (7/48) had an axillary sentinel lymph node biopsy of whom one was positive. 33% of patients (16/48) had an axillary lymph node dissection which was positive for one patient. 19% (n=9) had adjuvant radiotherapy and 15% (n=7) had adjuvant chemotherapy. 33% (n=10) of patients with partial mastectomy had at least one recurrence, versus 5.5% (n=1) after a total mastectomy. The average time between the diagnosis and the first recurrence was 25.4 months [range: 1-50]. 64% (n=7) had a second partial mastectomy and only 18% (n=2) had a total mastectomy. 27% of patient had chemotherapy after their first recurrence and 27% had radiotherapy if it was not received in first line treatment. 40% (n=4/10) of patients with partial mastectomy who recurred have had at least 2 breast recurrences. 28% (n=14) of all patients had distant metastases. 20% of patients (n=10) died whose 80% (n=8) had distant metastatic disease.

This systematic review provided a precise summary of the clinical characteristics and treatment of patients presenting with Malignant breast myoepithelioma in the past 40 years. We anticipate that these results will help inform current investigations and treatment.