As immune checkpoint inhibitors are rapidly developing into the standard of care for patients with advanced melanoma, the value of diagnostic metrics to predict response to immunotherapy is steadily increasing. Next-generation sequencing-based parameters include tumor mutation burden (TMB) and genomic amplification of PD-L1/PD-L2/JAK2 at 9p24.1. At present, there are limited studies documenting response to checkpoint blockade in 9p24.1-amplified solid tumors. Herein, we have compared a cutaneous melanoma with a mucosal melanoma, both with 9p24.1 amplifications and durable response to immunotherapy. Although the cutaneous melanoma had a high TMB, the mucosal melanoma had a lower TMB compared with the mean TMB for all melanomas within the institutional clinical sequencing cohort. In summary, PD-L1/PD-L2/JAK2 amplification was associated with durable response to therapy for both cases, and this genomic signature is a potential valuable metric in predicting response to immunotherapy.