Effect of protein-intake on tumor-growth and host survival in tumor-bearing animals

Nutritional repletion of the tumor-bearing host remains controversial. The present study was performed to determine the effect of protein intake on tumor growth and host survival in tumor-bearing animals. Forty-three female C2H mice with subcutaneous mammary tumor implants (MA 16/C) were randomized to receive standard protein diet or an isocaloric, protein-depleted diet ad libitum per os. Body weight and tumor volume were measured throughout the study and ail animals were maintained on these diets until death. Body weight was significantly greater in animals receiving standard protein intake compared to those given the protein-depleted diet. However, tumor growth was significantly stimulated and host survival reduced in animals given standard protein diet compared to animals maintained on protein-depleted diet. Thus, exogenous protein intake preferentially benefitted tumor versus host anabolism in this animal model with significant reduction in host survival.