Effect of total parenteral nutrition on the protein kinetics of patients with cancer cachexia

Aims and background: The question of whether TPN is able to reverse lean bo dy mass depletion in cachectic cancer patients and, in particular, its effe ct on protein kinetics Is a matter of some controversy. This study investig ates the impact of TPN on protein kinetics in patients with gastric cancer. Methods: The study involved three patients with 14-30% weight toss. They we re administered a TPN regimen including 33-40 kcal/kg/day and 1.4-1.7 g ami no acid/kg/day. The protein metabolism was studied before and during TPN us ing a stable amino acid isotope. Results: Whole body protein turnover and breakdown did not change during TP N, whereas whole body protein synthesis Increased from 3.39 +/- 1.04 to 6.0 5 +/- 0.48 g/kg/day (P = 0.03). However, the net balance, which was slightl y negative prior to TPN, became positive during nutritional support. In the skeletal muscle compartment the synthesis improved with TPN (from 9.38 +/- 2.6 nmol/100 mL/mln to 35.95 +/- 3.4 nmol/100 mL/min; P = 0.0143), whereas breakdown did not change significantly. Conclusions: TPN triggers a positive metabolic response in cachectic cancer patients. Whether this results in a clinical benefit for the patient requi res further Investigation.