Abstract
Background
The American Joint Committee on Cancer (AJCC8) and Brigham and Women's Hospital are the most commonly used staging systems for cutaneous squamous cell carcinoma (CSCC). Both have limitations.Objective
To develop a novel CSCC staging system (COMPASS-SCC) with improved performance.Methods
This study utilized a retrospective CSCC database from 12 international centers. Univariable and multivariable Fine and Gray models assessed risk factors' impact on major poor outcomes (MPO; metastasis and disease specific death) for inclusion and weight in the staging system. Sensitivity, specificity, positive and negative predictive value (PPV/NPV), Area Under the Receiver Operating Characteristic curve (AUROC), and Uno's c-index were calculated.Results
20,972 primary tumors were included. Diameter (1 point for ≥2 but 6 millimeters), differentiation (1 point for moderate, 2 points for poor), large-caliber perineural invasion (1 point), and lymphovascular invasion (1 point) were included in the system, with stages from T1 (0 points) to T4 (≥5 points). Sensitivity, NPV, AUROC, and Uno's c-index were significantly higher in COMPASS-SCC than in AJCC8 and BWH.Limitations
Retrospective design.Conclusion
COMPASS-SCC is a novel CSCC staging system with improved prognostic performance compared to AJCC8 and BWH.