da Silva IP, Lo S, Quek C, et al. - Among patients with metastatic melanoma treated with combination ipilimumab and anti–PD-1 therapy, researchers analyzed the patterns of response and survival and determined the nature of pseudoprogression and acquired resistance. This study included 140 patients with 833 metastases. With an increase in tumor burden or the number of metastases, a decline in overall response rate (ORR) and the overall complete response rate was evident. Superior ORR and progression-free survival were observed in patients with lung metastases, as revealed in multivariate analysis, whereas inferior ORR, progression-free survival, and overall survival were observed in those with liver metastases. Following a median of 9.6 months, the occurrence of acquired resistance was reported in 12% of responders, with 83% being overall survival rate at 1 year from progression. Distinct response patterns were demonstrated by metastases in different anatomical locations, which also showed relation to overall response and survival with combination immunotherapy. Possibly, particular sites of disease hold unique mechanisms of resistance and should permit for more personalized treatment.