Response of tumor-bearing rats to high-fat total parenteral nutrition

Total parenteral nutrition (TPN) solutions fed to tumor-bearing rats have been shown to affect host and tumor metabolism. This study was initiated to evaluate the effect of two intravenous nutrient regimens on carcass and organ composition as well as tumor composition and growth. Thirty Sprague-Dawley rats were implanted with Walker 256 carcinosarcoma and randomly assigned to one of three diet groups: (1) A, a glucose-based TPN formula; (2) B, a lipid-based TPN formula, isocaloric to A; and (3) C, a purified powdered diet fed ad libitum. Equal assignments were made for non-tumor-bearing controls. Tumor-bearing rats infused with diet B had the highest amount of carcass and organ fat as well as the lowest carcass and organ protein. Tumor composition paralleled carcass composition, but tumor weight and density did not differ among dietary groups. Tumor weight to body weight ratios were highest in the group fed diet B. These data indicate that although tumor growth remains unchanged, alterations in body and tumor composition are effected by a high fat TPN solution.