PD-1 inhibitor treatment outcomes for cutaneous squamous cell carcinoma in patients over 85: a comparative analysis.

[BACKGROUND] Programmed-cell death protein 1 (PD-1) inhibitors have become standard of care in the treatment of advanced or metastatic cutaneous squamous cell carcinoma (cSCC). However, insufficient data exists regarding treatment outcomes and safety among elderly patients, including patients aged >85.

[PATIENTS AND METHODS] We retrospectively reviewed patients aged >85 (n = 52) and compared them with two control groups: 46 patients aged 71-84 and 32 patients <70, treated with cemiplimab for cSCC. Demographics, treatment characteristics, outcomes and toxicity were evaluated. Inverse probability of treatment weighting (IPTW) was applied when comparing survival outcomes.

[RESULTS] Although patients >85 had worse ECOG scores and less inclined to undergo surgery, no significant differences were noted in the overall response rates (68.8% and 76.1% for <70 and 71-84, respectively vs. 73.1% for >85, P = .744) or disease control rates (75% and 82.6% for <70 and 71-84, respectively vs. 75% for >85, P = .627). After IPTW adjustment, progression-free survival (PFS) did not differ between groups (HR = 1.08, 95% CI 0.55-2.13, P = .82). Cancer specific survival (CSS) also did not differ between groups (HR = 1.05, 95% CI 0.22-4.87, P = .955). However, overall survival (OS) was shorter among patients >85 (HR = 2.64, 95% CI 1.43-4.86, P = .002). Toxicity profiles were similar, although toxicity-related deaths occurred more frequently in the >85 cohort.

[CONCLUSION] Cemiplimab showed comparable efficacy and tolerability across age groups, with no significant difference in PFS and CSS, but shorter OS among very elderly patients with cSCC, reflecting competing non-cancer mortality rather than reduced treatment efficacy.