High-Dose Radiation as a Dramatic, Immunological Primer in Locally Advanced Melanoma.

ABSTRACT

A 53-year-old white male presented with a right axillary melanoma that became widely metastatic and progressive despite multiple systemic treatments. He became refractory to ipilimumab (Yervoy) and pembrolizumab (Keytruda). He presented with a very large, painful left posterior neck mass that was 18 x 15 x 8 cm in size clinically. He was treated with a single fraction of 20 Gy using parallel opposed, spatially fractionated GRID radiation therapy (SFGRT), along with concurrent pembrolizumab. He also received 50 Gy in 25 fractions of conventional radiation. After five months of concurrent treatment, the refractory neck mass had completely resolved and he had no lasting side effects. Our dramatic case confirms the synergistic effect of high-dose GRID radiation as a primer for renewed, enhanced immunological response, and we have used this approach successfully on a number of similar patients with rapid and durable results.