Guidelines for the use of sentinel node biopsy in early-stage breast cancer

This report offered updated guidelines for the use of sentinel node biopsy and axillary lymph node dissection in early-stage breast cancer.

Breast cancer patients often undergo a sentinel node biopsy (an examination of tissue removed from the body) to determine whether or not their cancer has spread to the first most likely lymph node, often located in the axilla (armpit area). Some women also undergo an axillary lymph node dissection, a surgical procedure to remove lymph nodes from the axilla.

Guidelines for the use of sentinel node biopsy and axillary lymph node dissection were first written in 2005. To include research undertaken since then, the American Society of Clinical Oncology reviewed recent literature and data to agree on the updated recommendations. The current guideline update outlines their recommendations on the use of sentinel node biopsy and axillary lymph node dissection in early-stage breast cancer patients.

Since 2005, 9 studies have addressed the overall question of how sentinel node biopsies should be used in breast cancer treatment. The first recommendation is that women who do not show metastasis (spread) of cancer following a sentinel node biopsy (a negative biopsy) should not undergo axillary lymph node dissection. Seven studies, including more than 4,000 patients, show that axillary lymph node dissection did not significantly increase survival rates: 91.8% of patients who underwent axillary lymph node dissection had an overall survival rate of 8 years, compared to 90.3% who only underwent sentinel node biopsy. Recurrence rates and time to progression were also similar in the two groups of patients. Adverse effects, however, were significantly higher following axillary lymph node dissection, including lymphedema, or swelling of the arms and legs.

The second recommendation states that axillary lymph node dissection is not necessary for women with lymph node metastasis (a positive sentinel node biopsy) who are planning to have whole-breast radiotherapy. Axillary lymph node dissection did not significantly affect overall survival, time to progression, or recurrence rates in these patients, but did significantly increase adverse effects. One study reported a 13% lymphedema rate following axillary lymph node dissection, compared to 3% in patients who did not have the procedure. However, it is recommended that women who will undergo mastectomy (surgical operation to remove the breast) without radiotherapy undergo axillary lymph node dissection, though this recommendation is based on the results of one small study.

Sentinel node biopsy is recommended for women with more than one tumor (multicentric tumors), women with ductal carcinoma in situ who are undergoing mastectomy, women with prior breast or lymph node surgery, or women undergoing neoadjuvant chemotherapy (chemotherapy administered before surgery).

Sentinel node biopsy is not recommended for women with very large tumors or those that have advanced locally into the chest wall who will undergo a mastectomy. It is also not recommended for women with ductal carcinoma in situ who will undergo breast-conserving surgery (lumpectomy), women with inflammatory breast cancer, and women who are pregnant. There is insufficient evidence that sentinel node biopsy benefits these women.

The current guideline update recommended sentinel node biopsy without axillary lymph node dissection for most early-stage breast cancer patients, due to the low benefits and high risks of the procedure.