Breast radiotherapy for occult breast cancer with axillary nodal metastases--does it reduce the local recurrence rate and increase overall survival?

AIMS

The optimal management of axillary lymph node metastases from occult breast cancer (TXN1-2M0) is uncertain and practice varies in the use of primary breast radiotherapy. We conducted a retrospective review to examine clinical outcomes for patients managed with or without primary breast radiotherapy.

MATERIALS AND METHODS

Case records from the clinical oncology database were reviewed to identify patients presenting with axillary nodal metastases but no detectable primary tumour between 1974 and 2003. Fifty-three patients with TXN1-2M0 breast cancer were identified, representing 0.4% of patients managed for breast cancer during this period. Of those tested, 59% had oestrogen receptor-positive tumours. Seventy-seven per cent received ipsilateral breast radiotherapy.

RESULTS

There was a trend towards reduced ipsilateral breast tumour recurrence in patients who received radiotherapy (16% at 5 years, 23% at 10 years) compared with those who did not (36% at 5 years, 52% at 10 years). Similarly, the locoregional recurrence rate was 28% at 5 years for patients who received radiotherapy compared with 53.7% at 5 years for non-irradiated patients. Breast cancer-specific survival was higher (P=0.0073; Log-rank test) in patients who received ipsilateral breast radiotherapy (72% at 5 years, 66% at 10 years) compared with those who did not (58% at 5 years, 15% at 10 years).

CONCLUSION

Primary breast radiotherapy may reduce ipsilateral breast tumour recurrence and may increase survival in patients presenting with axillary lymph node metastases and occult breast primary (TXN1-2M0). Larger studies or prospective registration studies are needed to validate these findings.