A sentinel lymph node biopsy is feasible and safe for patients treated with neoadjuvant chemotherapy for a large breast tumour and no clinical signs of the cancer in the axillary lymph nodes

A sentinel lymph node biopsy (SLNB) during surgery that showed no signs of cancer was associated with a low risk for breast cancer recurrence in the axillary (armpit) lymph nodes for patients with large, operable breast tumours and no clinical signs of the cancer in the axillary lymph nodes prior to neoadjuvant (presurgery) chemotherapy. Axillary lymph node dissection (ALND) in which many of the lymph nodes in the armpit are removed, is often performed to check whether a patient’s cancer has spread outside the breast after neoadjuvant chemotherapy. ALND has a high risk for serious complications and long-term sequelae. The aim of the GANEA-2 trial was to assess the feasibility and safety of the less invasive procedure of SLNB for patients treated with neoadjuvant chemotherapy for a large breast tumour.

In the GANEA-2 trial, 590 patients with large, operable breast tumours who had no cancer in the lymph nodes as determined by axillary sonography with fine needle cytology were included. All patients received neoadjuvant chemotherapy and then underwent surgery and SLNB.

Cancer cells were detected in the SLNB samples of 139 patients; these patients all underwent ALND. No cancer cells were detected in the SLNB samples of 432 patients. Among these 432 patients, follow-up was available for 418 patients. Median follow-up for these patients was 36 months. At three years, disease-free survival in the patients who had no cancer in the SLNB sample and, therefore, did not receive ALND was 94.8%. One patient had a homolateral axillary lymph node relapse. The other nine relapses were metastatic (N=3) or recurrences in the breasts (N=6). Overall survival was 97.8%.

The disease-free and overall survival results observed for the patients who underwent only an SLNB after neoadjuvant chemotherapy were comparable with the historical survival rates for patients in this situation who had ALND rather than SLNB. Therefore, an ALND could be avoided for patients who have no signs of cancer in the axillary lymph nodes following a sonographic axillary assessment prior to neoadjuvant chemotherapy and SLNB during surgery after neoadjuvant chemotherapy. Longer follow-up of the patients is needed to further confirm the safety of SLNB for these patients.

Reference

Classe JM, Loaec C, Alran S, et al. Sentinel node detection after neoadjuvant chemotherapy in patient without previous axillary node involvement (GANEA 2 trial): follow-up of a prospective multi-institutional cohort. San Antonio Breast Cancer Symposium 2016, abstract S2-07