Stratification of Poor Outcomes for Cutaneous Squamous Cell Carcinoma in Immunosuppressed Patients Using the American Joint Committee on Cancer Eighth Edition and Brigham and Women's Hospital Staging Systems.

BACKGROUND: Staging systems for cutaneous squamous cell carcinoma (CSCC) include Brigham and Women's Hospital (BWH) and American Joint Committee on Cancer staging system, eighth edition (AJCC-8).

OBJECTIVE: To evaluate and compare AJCC-8 and BWH staging systems for CSCC in immunosuppressed patients.

MATERIALS AND METHODS: A retrospective cohort study of immunosuppressed patients diagnosed with primary CSCC from 2012 to 2016. The main end point was any poor outcome (PO), which included local recurrence, nodal metastasis, and disease-specific death.

RESULTS: Fifty-eight immunosuppressed patients had 263 CSCCs. Fifty percent of tumors were AJCC-8 T1, 44.7% T2, and 4.8% T3. Fifty percent of tumors were BWH T1, 48.5% T2a, 1.3% T2b, and 0.4% T3. Risk of PO for AJCC-8 was 1.7%, 8.8%, and 36.4% for T1, T2, and T3, respectively (p < .01). Risk of PO for BWH was 1.8%, 9.9%, 33.3%, and 100.0% for T1, T2a, T2b, and T3, respectively (p < .01). Thirty-six percent of AJCC-8 T3/T4 tumors had POs compared with 5.1% in low T1/T2 stages (p = .002). Fifty percent of BWH T2b/T3 tumors had POs compared with 5.3% in low T1/T2a stages (p = .01).

CONCLUSION: AJCC-8 and BWH staging systems stratify CSCC with similar distinctiveness, homogeneity, and monotonicity for immunosuppressed patients.