A commentary notes these results are surprising as the investigators had postulated that obesity would be associated with an adverse outcome in patients with stage IV melanoma, and also because of the large magnitude of the beneficial effect. It calls for these findings to be validated in studies of immune therapy and targeted therapies in the adjuvant setting in melanoma, and also for investigations into the biological mechanisms underpinning the results as a potential avenue for modulating and improving current treatment. It cautions that these results apply only to male patients in one tumour type undergoing targeted or immune therapy and, because of the complexity of the relation between obesity and cancer, as yet they should not be extrapolated further.