Occult primary breast carcinoma presenting as axillary lymphadenopathy.

Background: The objective of this study was to review the need for radiotherapy or not in patients with occult primary breast cancer presenting with axillary metastases treated with breast conservation usually with no surgery to the breast.

Methods: From 1975 to 2001, 58 patients were treated with axillary lymphadenopathy from a cryptic primary breast carcinoma. After clinical and radiological assessment, 29 patients retained a diagnosis of occult primary breast carcinoma. Clinical and pathological data were collected retrospectively on the 29 patients and survival was calculated from the date of initial diagnosis using the Kaplan-Meier method. The median follow-up was 44 months.

Results: Median age at diagnosis was 57 years (range 28-81 years). Sixteen patients had radiotherapy to the ipsilateral breast. Eleven patients received no local therapy to the ipsilateral breast and two patients had quadrantectomies which were negative for malignancy. Locoregional relapse occurred in 12.5% of patients who had received radiotherapy and 69% of those who had not received any radiotherapy (P=0.02). Fifty-seven per cent of patients having a local relapse were salvaged with further surgery. The eventual breast conservation rate was 93%. Patients who received radiotherapy to the breast had significantly improved relapse-free survival (HR=0.31; P=0.04) and local relapse-free survival (HR=0.09; P=0.004). There were no significant differences in overall survival between those patients who had breast irradiation and those who did not (HR 0.91; 95% CI 0.18-4.5).

Conclusion: Occult primary carcinoma with axillary metastases can be treated successfully with breast preservation but radiotherapy to the breast is necessary to minimize the risk of locoregional recurrence.