Evaluation of the Definitions of “High-Risk” Cutaneous Squamous Cell Carcinoma Using the American Joint Committee on Cancer Staging Criteria and National Comprehensive Cancer Network Guidelines

Recent guidelines from the American Joint Committee on Cancer (AJCC) and National Comprehensive Cancer Network (NCCN) have been proposed for the assessment of "high-risk" cutaneous squamous cell carcinomas (cSCCs). Though different in perspective, both guidelines share the common goals of trying to identify "high-risk" cSCCs and improving patient outcomes. Thus, in theory, both definitions should identify a similar proportion of "high-risk" tumors. We sought to evaluate the AJCC and NCCN definitions of "high-risk" cSCCs and to assess their concordance. Methods. A retrospective review of head and neck cSCCs seen by an academic dermatology department from July 2010 to November 2011 was performed. Results. By AJCC criteria, most tumors (n = 211,82.1%) were of Stage 1; 46 tumors (13.9%) were of Stage 2. Almost all were of Stage 2 due to size alone (≥2 cm); one tumor was "upstaged" due to "high-risk features." Using the NCCN taxonomy, 231 (87%) of tumors were "high-risk." Discussion. This analysis demonstrates discordance between AJCC and NCCN definitions of "high-risk" cSCC. Few cSCCs are of Stage 2 by AJCC criteria, while most are "high-risk" by the NCCN guidelines. While the current guidelines represent significant progress, further studies are needed to generate a unified definition of "high-risk" cSCC to optimize management.