The American Society of Clinical Oncology and the Society of Surgical Oncology have jointly released their first evidence-based clinical practice guideline for use of sentinel lymph node biopsy (SLNB) to stage patients with newly diagnosed melanoma.
The recommendations, based on a review of recent evidence suggesting that SLNB has been inconsistently used in current practice, clarify which patients should undergo the procedure. The review and new guideline are now available online ahead of print in both the Journal of Clinical Oncology (DOI: 10.1200/JCO.2011.40.3519) and Annals of Surgical Oncology (DOI: 10.1245/s10434–012–2484–2).
“When used for the right patients at the right time, sentinel lymph node biopsy is one of our best tools for personalizing melanoma treatment, and for sparing patients from unnecessary procedures or therapies,” Sandra L. Wong, MD, lead author and Co-chair (with Gary H. Lyman, MD, MPH) of the guideline panel and Assistant Professor of Surgery at the University of Michigan, explained in a news release. “But we know this procedure is used inconsistently in the United States.”
A multidisciplinary panel of 14 clinical and methodological experts (convened by ASCO and SSO) reviewed the literature published between 1990 and 2011, including 73 studies involving some 25,000 patients. SLNB was found to be associated with rates of patients successfully mapped (the primary endpoint of the literature review) of 97 to 98 percent; and false-negative rates using SLNB were found to be as low as between 13 and three percent.
The major recommendations are as follows:
- SLNB is recommended for patients with intermediate-thickness melanomas (1 to 4 mm) of any anatomic site. These patients constitute about a third of all melanoma cases, the guideline states.
- Evidence is thus far insufficient to recommend routine use of SLNB for patients with thin tumors (less than 1 mm), which are the most common form of melanoma. For these cases, surgery can usually completely remove the primary tumor. But, the paper notes that SLNB should be considered for patients with thin melanomas who have a high risk for metastasis, including patients with ulcerated tumor or rapidly dividing cancer cells.
- For thick melanomas (greater than 4 mm), the guideline recommends that SLNB may be considered. These tumors are less common than smaller melanomas, but are more likely to spread—and less conclusive research exists on this group of tumors. Even though several studies show SLNB can help provide important staging and diagnostic information, and is associated with better regional disease control, overall survival benefits have not been conclusively proven.
- “Completion lymph node dissection” is recommended for all patients with a positive SLNB and has been found to achieve good regional disease control—although survival benefits for the procedure after a positive SLNB are still the subject of ongoing research, the guideline notes.