Risk of Merkel Cell Carcinoma Progression After Treatment Discontinuation in Patients With an Objective Response to Anti-PD-(L)1 Immunotherapy
TLDR Longer immunotherapy treatment may improve outcomes for Merkel cell carcinoma patients.
This retrospective study evaluated the progression of Merkel cell carcinoma (MCC) in 105 patients who responded to first-line anti-PD-(L)1 immunotherapy (IMTX). With a median follow-up of 34 months, 58 patients had discontinued IMTX (median duration: 12 months) and 47 continued (median duration: 17.8 months). The 2-year progression-free fraction (PFF) was 75% overall, 63% for those who discontinued, and 80% for those who continued IMTX. Patients treated for ≥18 months had better PFF rates compared to shorter durations. Those with partial responses had higher progression rates after discontinuation than those with complete responses. The study suggests that extended IMTX duration may improve outcomes, warranting further research on prolonged treatment strategies.