Comparative Performance of Four Staging Classifications to Select «High-Risk» Head and Neck Cutaneous Squamous Cell Carcinomas.

Background: Many classifications exist to select patients with "high-risk" head and neck cutaneous squamous cell carcinoma (HNCSCC).
Objective: To compare the performance of the Brigham and Women's Hospital (BWH) classification with the performance of the American Joint Committee on Cancer 8th Edition (AJCC8), the Union for International Cancer Control 8th Edition (UICC8), and the National Comprehensive Cancer Network (NCCN) classifications.
Methods: In this single-center retrospective study, HNCSCC resected in a tertiary care center were classified as "low-risk" or "high-risk" tumors according to the four classifications. Rates of local recurrence (LR), lymph node recurrence (NR), and disease-specific death (DSD) were collected. The performance of each classification was then calculated in terms of homogeneity, monotonicity, and discrimination and compared.
Results: Two hundred and seventeen HNCSCC from 160 patients, with a mean age of 80 years, were included. For predicting the risk of any poor outcome and risk of NR, the BWH classification had the best specificity and positive predictive value. However, its concordance index was not significantly higher than that of the AJCC8 and UICC8 classifications. The NCCN classification was the least discriminant.
Conclusions and Relevance: This study suggests that the BWH classification is the most appropriate for predicting the risk of poor outcomes in patients with HNCSCC when compared with the NCCN, UICC8, and AJCC8 classifications.