Sentinel Lymph Node Biopsy in Breast Cancer Treatment: Indications and Contraindications

In Québec, roughly 6200 women have been diagnosed with breast cancer in 2011. Today, owing in part to the Québec Breast Cancer Screening Program, this type of cancer is diagnosed more often at an early stage, allowing less invasive surgical procedures, that is, lumpectomy and sentinel lymph node biopsy (SLNB). The latter technique consists in injecting either a radioactive tracer or a blue dye, or both, into the breast in order to surgically detect the primary lymph nodes likely to harbour metastases if the cancer has spread.

Not all patients with breast cancer are eligible for SLNB. Several specific medical situations are contraindications for SLNB, in some cases owing to a lack of scientific evidence. Given the technical advances and new publications in this field, some believe that it is time to reconsider some of these contraindications. The Comité de l’évolution des pratiques en oncologie (CEPO) therefore asked us to examine the validity of the available evidence on the indications and contraindications for SLNB.

This is an exhaustive review of the feasibility (SLN identification rate) and diagnostic accuracy (risk of false negatives) of SLNB in the following medical situations: (1) after neoadjuvant chemotherapy; (2) presence of large tumours (> 5 cm); (3) after non-oncological breast surgery, such as breast augmentation or reduction mammoplasty; and (4) after prior SLNB, in the case of tumour recurrence.

This report also presents the recommendations issued by recognized major international organizations concerning the four medical situations mentioned above in addition to the following specific situations: presence of clinically suspicious palpable axillary nodes, presence of ductal carcinoma in situ (DCIS), pregnant patients, presence of inflammatory breast cancer, presence of a multicentric or multifocal tumour, presence of bilateral cancer, older age, obesity, male breast cancer, and prior excisional or diagnostic breast biopsy.