Cisplatin is a nephrotoxic agent able to damage renal function both in acute and chronic phases. Radiotherapy concomitant with cisplatin 100 mg/m² given once every 3 weeks is the curative standard of care for locally advanced head and neck cancer. A prospective evaluation of a wide range of biochemical and anthropometrical parameters, handgrip strength, risk of malnutrition, visual analogue scale
... [Show full abstract] of appetite, and body composition was performed before, during, and after concomitant chemoradiotherapy in 60 consecutive patients affected by locally advanced head and neck cancer. The treatment dramatically influenced every clinical and laboratory parameter, especially regarding nutritional status despite a high protein intake. In terms of medium eGFR decay, chemoradiotherapy reduced the renal function of about 8 ml/min/1.73m² in 6 weeks, harboring some cases of mild acute kidney injury and acute kidney disease. Furthermore, patients with eGFR < 60 mL/min/1.73m² pre-treatment were just 3 (5%), becoming 5 (8.3%) at the end despite the high-protein diet implemented following ESPEN guidelines. The drop in eGFR did not correlate with weight loss during treatment or with anthropometric parameters pre and post. Nutritional counselling pre-, during, post-treatments plays a crucial role in preventing malnutrition and sarcopenia, leading to better oncological and nephrological outcomes too.