Effects of selenium and zinc supplementation on nutritional status in patients with cancer of digestive tract

Objective: To evaluate the effect of oral administration of selenium and zi nc tablets in patients with cancer of the digestive tract during chemothera py. Design: A case-control, randomized study. Setting: Medical Oncology, II University of Naples, Naples, Italy. Subjects: A total of 60 patients (median age 55 y, range 46-61 y) with diag nosis of gut cancer were randomized in 1999. Patients were treated for 60 d ays with chemotherapy. Interventions: Trace elements were measured by atomic absorption spectrosco py. The nutritional status of the patients was assessed by biochemical and bio-impedance analysis (BIA) parameters in basal condition and after 60 day s of treatment. Oral administration of selenium and zinc in oral tablet for m for 50 days was Se 200 mug/day (50 mug/tablet) and Zn 21 mg/day (7 mg/tab let). Results: Both in the basal condition and at 60 days all patients were malno urished. Selenium and zinc concentrations were significantly lower (P < 0.0 1) whereas copper concentration was significantly higher (P < 0.01) in canc er patients than in control subjects. However, 21/30 (70%) of those treated with Se and Zn did not showed a further worsening of nutritional status an d experienced a significant decrease of asthenia with an increase of appeti te. On the other hand, 24/30 (80%) untreated patients had a significant dec line of all parameters studied after 60 days (prealbumin, cholesterol, tran sferrin, P < 0.05 vs 0 time; total proteins, albumin/globulin ratio, P < 0. 01 vs 0 time; fat-free mass, fat mass, Na+/K+ ratio, body mass index P < 0. 05 vs 0 time; fat free mass/fat mass, total body water, extra cellular/intr a cellular water, basal metabolic rate: P < 0.01 vs 0 time). Conclusions: Data indicate that Se and Zn supplementation may improve the c linical course of general conditions in patients with gut cancer. These eff ects of Se and Zn require confirmation in an independent trial of appropria te design before new public health recommendations regarding Se and Zn supp lementation can be made.