Breast cancer arising within fibroadenoma: collective analysis of case reports in the literature and hints on treatment policy.

BACKGROUND

Breast cancer arising within a fibroadenoma (BcaFad) is rare; the rate varies from 0.002% to 0.125% in fibroadenoma specimens. Owing to its rarity, the clinicopathologic feature and treatment principle of BcaFad is still not clear. Therefore, the aim of this study was to perform a collective analysis of case reports in the literature to identify the characteristics and optimal treatment for BcaFad.

METHODS

We analyzed an aggregated sample of 30 patients with BcaFad from case reports in the literature (n=24 cases) and our present study (n=6 cases). We collected and analyzed the clinicopathologic features and prognoses of patients with BcaFad, as well as treatments they received.

RESULTS

The patients' mean age at diagnosis was 46.9 years. Twenty BcaFad patients (66.7%) received breast-conserving surgery (BCS), and nine other patients (30.0%) were treated with mastectomy. The rate of lymph node metastasis in BcaFad patients was 23.8%. The breakdown of the histological types of BcaFad was invasive ductal carcinoma (53.3%), followed by ductal carcinoma in situ (23.3%), lobular carcinoma in situ (16.7%) and invasive lobular carcinoma (13.3%). More than half of patients with positive hormone receptor status received hormone therapy. Most BcaFad patients with lymph node metastases received chemotherapy, and 20.0% of BcaFad patients treated with BCS received further radiotherapy. Only one patient had recurrence after surgery, and another had lung metastasis when diagnosed with BcaFad.

CONCLUSIONS

Most BcaFad patients could be managed by BCS. Adjuvant radiotherapy could be performed, but was not mandatory. Chemotherapy should be considered as a treatment option in the presence of lymph node metastasis.