Validation of Current Staging Systems in HNCSCC: A Multinational Cohort Study

Area of Science:

• Oncology
• Dermatology
• Head and Neck Surgery

Background:

• Effective risk stratification is crucial for managing cutaneous squamous cell carcinoma (CSCC).
• The American Joint Committee on Cancer (AJCC) 8th edition (AJCC8) staging system has limitations in T-stage distinctiveness for CSCC.
• The Brigham and Women's Hospital (BWH) system offers an alternative for CSCC risk stratification.

Purpose of the Study:

• To compare the effectiveness of the BWH and AJCC8 staging systems.
• To evaluate their ability to predict poor outcomes in head and neck (HN) CSCC.
• To assess prediction accuracy for local recurrence, nodal recurrence, distant recurrence, and disease-specific death.

Main Methods:

• Retrospective, multinational cohort study including 9852 excised tumors from 3168 patients.
• Data collected from 12 centers across the United States, Spain, and Brazil between 1991 and 2023.
• Patients with invasive CSCC undergoing curative-intent surgery were included; specific exclusions applied.

Main Results:

• Both BWH and AJCC8 systems demonstrated comparable monotonicity and homogeneity.
• Significant differences in 5-year cumulative incidence for disease-specific death (DSD) were observed for both systems, and for local recurrence (LR) with the BWH system.
• Both staging systems showed high specificity and negative predictive value (NPV), low sensitivity and positive predictive value (PPV), and moderately high c-indices for predicting outcomes in HNCSCC.

Conclusions:

• Current AJCC8 and BWH staging systems accurately predict survival in head and neck CSCC.
• Future staging systems require refinement to better stratify patients based on other key outcomes.
• Further research is needed to enhance the distinctiveness of T-stages for improved CSCC management.