Sarcopenic overweight is associated with early acute limiting toxicity of anti-PD1 checkpoint inhibitors in melanoma patients.

Little is known on factors predicting toxicity of anti-PD1 checkpoint inhibitors. Sarcopenic obesity is associated with increased acute toxicity of cytotoxic agents and targeted therapies. We explored whether body composition also influenced the occurrence of early acute limiting toxicity (ALT) of anti-PD1 in melanoma patients. This is a monocentric, retrospective study analyzing toxicity outcome in consecutive melanoma patients treated with nivolumab or pembrolizumab. Various parameters linked to the patient or the disease status have been analysed. Body mass index (BMI; kg/m2 ) and muscle mass using CT were measured prior to treatment initiation. Chi-squared test and Mann-Whitney's tests were used for the comparison of categorical and continuous variables respectively. Among 68 melanoma patients treated with anti-PD1 (47 pembrolizumab, 21 nivolumab), 38 (56%) patients had a BMI ≥ 25 kg/m2 and 11 (16%) a BMI ≥ 30, while 13 (19%) had both sarcopenia and a BMI ≥ 25 kg/m2 . For the 11 (16%) patients who experienced early ALT, the mean BMI was higher (27.9 versus 24.7 kg/m2 ; p = 0.04). Among the 32 female patients, sarcopenic overweight patients had a 6.5-fold increased risk of ALT (50 versus 7.7%; p = 0.01). Sarcopenic overweight is associated with more early ALT of anti-PD1 in melanoma patients.