Incidence of intramammary nodes in completion mastectomy specimens after axillary node sampling: implications for breast conserving surgery.

Background: Axillary node sampling (ANS) is widely used in conjunction with breast conserving surgery in the treatment of primary breast cancers in the UK. Some evidence suggests that axillary staging techniques can miss intramammary nodes contained within the axillary tail of the breast. This study aims to assess the incidence of such nodes in completion mastectomy specimens in women who have had previous breast conserving surgery and ANS.

Methods: One hundred and fifty-seven completion mastectomy specimens were obtained from women who had previous breast conserving surgery and ANS, at the Nottingham Breast Institute over a 3-year period. The pathology samples underwent detailed histological examination to identify lymph nodes, and determine their disease status.

Results: Seventy-six (48%) of completion mastectomy specimens contained intramammary lymph nodes. Fifteen patients were upstaged (lymph node stage) because of the histological findings at completion mastectomy. One patient from the study population received additional systemic treatment, as a result of the upstaging.

Conclusion: The incidence of intramammary nodes in this series correlates with previous data. This study shows that in breast cancer patients who undergo ANS, intramammary nodes, if present and more so positive, are unlikely to change systemic treatment decisions, but may increase the number of patients needing radiotherapy and or further axillary dissection.