Testosterone deficiency in men receiving immunotherapy for malignant melanoma.

Immunotherapy has been established as a standard of care for patients with malignant melanoma, however, the long-term side-effects of immunotherapy are still emerging. Studies over the last decade have documented increasing reports of endocrine dysfunction following the initiation of immunotherapy. Our study aimed to detect the proportion of men who have low testosterone before, during, and or/after receiving immunotherapy for malignant melanoma, and to determine the proportion of men who receive testosterone replacement therapy after detection of low testosterone. We performed retrospective chart review of patients with malignant melanoma treated with immunotherapy. Low testosterone was identified in 34 out of 49 patients at some point during their treatment with immunotherapy. Despite low testosterone levels in two-thirds of patients, only three patients were treated with testosterone replacement therapy. In addition to laboratory evidence of low testosterone, patients were also symptomatic as 43 out of 49 patients reported fatigue to their providers. Four patients developed hypophysitis and subsequent hypopituitarism, all of whom were receiving Ipilimumab. We conclude that patients with stage 3 or 4 melanoma treated with immunotherapy appear to be at an increased risk of developing testosterone deficiency during their treatment.