Clinical and Patient-Reported Outcomes in C-POST: Phase 3 Trial of Adjuvant Cemiplimab versus Placebo for High-Risk Cutaneous Squamous Cell Carcinoma

with worse OS (p=0.05),whereas longer symptom-to-diagnosis interval correlated with improved OS (p<0.001).Other clinicopathologic and immunophenotypic features were not independently prognostic.Conclusions: PCGDTCL is a rare disease with unique clinicopathologic characteristics and overall poor prognosis.Treatment strategy, particularly allogeneic SCT, emerges as the strongest determinant of long-term survival, while hemophagocytic syndrome identifies a high-risk subset.These findings support early risk stratification and consideration of curative-intent transplantation in eligible patients.