Chemotherapy Following PD-1 Inhibitor Blockade in Patients with Unresectable Stage III/Stage IV Metastatic Melanoma: A Single Academic Institution Experience.

Retrospective case studies in various cancers have shown clinical benefit from chemotherapy following PD-1 inhibitor progression. We asked whether we see a similar clinical benefit with chemotherapy following PD-1 inhibitor progression in metastatic melanoma. We performed a retrospective study in patients with metastatic melanoma, who had received PD-1 inhibitor-based treatments, subsequently progressed, and eventually received chemotherapy. We identified 25 patients (median age 58 years; range 31-77 years; 13 females). Most patients had cutaneous melanoma (72%), were BRAFV600E-negative (75%), and received single-agent temozolomide (84%). At a median follow-up of 21.0 months (range: 4.1-154.2 months), 2 patients had durable response to chemotherapy (progression-free survival is 31.9+ and 21.6+ months, respectively), and 1 patient had a partial, short-term response. We conclude that in this poor prognosis group administration of chemotherapy has a 12% response rate that can be durable. Overall, the clinical benefit is not inferior to that of PD-1 inhibitor-based treatments.