The potential role of breast conservation surgery and adjuvant breast radiation for adenoid cystic carcinoma of the breast.

Purpose: Adenoid cystic carcinoma (ACC) of the breast is a rare breast cancer variant and optimal management is unclear. A review of this unusual tumour was performed at our Institution, to assess the role of breast conservation in the management of this disease.

Methods And Materials: A review of all cases of ACC of breast (1960-2000) treated at Princess Margaret Hospital (PMH) was undertaken. Information was collected on age at diagnosis, presenting features, tumour size and treatment modalities. Treatment outcomes were evaluated.

Results: Eighteen female and one male patient were identified. Median age at diagnosis was 58 years (range 35-76 years). Four patients had lymph-node positive disease at presentation; the single male patient presented with metastatic disease. Surgery was either a lumpectomy (10 cases) or a simple, radical or modified radical mastectomy (9 patients). Nine of 19 patients received adjuvant radiotherapy (RT). The median follow-up time was 14 years; the recurrence rate at 10 years was 31% (95% CI 7-54%) with a range in time of recurrence from 2.3 to 11.9 years. Seven recurrences were identified (4 local, 1 regional, 2 metastatic). Two of these patients developed metastatic spread and died. Six of the 19 cases went on to develop second malignancies of whom four died. Among the 18 female patients, the 10-year overall (OS), cause-specific (CSS), and relapse free survival (RFS) rates were 75, 100, and 46% respectively.

Conclusions: ACC of the breast has a relatively prolonged natural history, and responds well to conservative management at presentation, with good outcome, even following local recurrence.