Recommendations on when to perform sentinel lymph node (SLN) biopsy in cutaneous squamous cell carcinoma (cSCC) are lacking despite the tumor's clear predilection for lymphatic spread.
To analyze the frequency of SLN metastasis in published series of cSCC in the context of the eighth edition of the American joint Committee on Cancer (AJCC-8) and the Brigham and Women's Hospital (BWH) staging criteria.
Systematic review of studies of patients with cSCC who underwent SLN biopsy that described biopsy results.
In total, 153 patients with 24 positive SLN biopsies (15.7%) were included. Based on the AJCC-8 criteria positivity rates in the T2 and T3 categories were 8.3% (1/12 patients) and 25% (8/32), respectively. Using the BWH system there were, 2/33 in category T2a (6.5%), and 5/17 in category T2b (29.8%). On applying the same criteria to tumors of the trunk and extremities the results were similar.
It would seem reasonable to recommend SLN biopsy for patients with AJCC-8 Stage T3+ disease or BWH Stage T2b/T3 disease. Both the AJCC-8 and the BWH systems would appear to be useful for staging cSCC of the trunk and extremities.