Effect of Total Parenteral Nutrition on the Protein Kinetics of Patients with Cancer Cachexia

Abstract

Aims and background The question of whether TPN is able to reverse lean body mass depletion in cachectic cancer patients and, in particular, its effect on protein kinetics is a matter of some controversy. This study investigates the impact of TPN on protein kinetics in patients with gastric cancer. Methods The study involved three patients with 14–30% weight loss. They were administered a TPN regimen including 33–40 kcal/kg/day and 1.4–1.7 g amino acid/kg/day. The protein metabolism was studied before and during TPN using a stable amino acid isotope. Results Whole body protein turnover and breakdown did not change during TPN, whereas whole body protein synthesis increased from 3.39 ± 1.04 to 6.05 ± 0.48 g/kg/day (P = 0.03). However, the net balance, which was slightly 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/min 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 requires further investigation.