head/neck (42%), lower extremities (36%), trunk (11%), upper extremities (9%), and vulva (2%).In 33% of cases (15/45), SCC arose from chronic skin lesions, predominantly burn scars (53%) and nonhealing wounds (33%).Anti-PD1 was first-line therapy in 35 pts (78%).Among 39 evaluable pts, ORR was 23% (CR 5% n=2 + PR 18% n=7), DCR 49% (ORR + SD 26% n=10).Among evaluable patients, median PFS was 4.1 mo (95% CI 2.63-11.5) in 36 pts (80%), with 24-and 36-monthPFS rates of 15.1% and 10.1%, respectively.Median OS was 19.9 mo (95% CI 12.4-NR) in 44 pts (98%), with 24-and 36-month OS rates of 39.2% and 33.6%.Cox regression (OS, n=44): lack of objective response (CR or PR) increased mortality risk (HR=11.96,95% CI1.55-92.26,p=0.017); female sex improved OS (HR=0.41,95% CI 0.17-0.96,p=0.041); mCSCC worsened OS(HR=2.79,95% CI 1.00-7.81,p=0.051).For PFS (n=36), lack of CR/PR (HR=10.85,95% CI 2.42-48.70,p=0.002) and mCSCC (HR=3.06,95% CI: 1.16-8.07,p=0.024) were significant.Prior chronic conditions, head/necklocation, and age were not significant. Conclusions:In Russian real-world practice, anti-PD-1 therapy for aCSCC showed an ORR of 23.1%, PFS median 4.1 mo, and OS median 19.9 mo, which were lower than those in pivotal clinical trials.Lack of response and metastatic CSCC significantly worsened PFS and OS, whereas female sex improved OS.Further research is needed to improve treatment approaches for aCSCC.
Law et al. (2026) studied this question.