Cessation of targeted therapy after a complete response in BRAF-mutant advanced melanoma: a case series

Background: It is unknown whether melanoma patients achieving complete response (CR) with targeted therapy can safely discontinue treatment. Methods: All patients treated with BRAF/MEK inhibitors achieving CR and ceasing treatment before progression were identified. Clinical data at treatment initiation, cessation and progression were examined. Results: A total of 12 eligible patients were identified, with median follow-up of 16 months, of whom 6 (50%) recurred at a median of 6.6 months after treatment cessation. One patient lost to follow-up until presentation with symptomatic recurrence was the only relapser to die. At relapse, the remaining five patients had an LDH <1.2 times ULN, four were ECOG 0 and one ECOG 1. Baseline characteristics and time to CR and to discontinuation did not influence the rate of relapse. Conclusions: A large proportion of patients achieving CR with BRAF/MEK inhibitors relapse after treatment cessation. The optimal treatment duration in such patients is unclear, particularly where alternative treatments are available.