The efficacy of total parenteral nutrition in malnourished tumor-bearing rats

The current study was designed to compare the efficacy of total parenteral nutrition (TPN), provided either before or after tumor removal, in replenishing protein stores in the malnourished tumor-bearing (TB) host. Fisher 344 rats bearing a transplantable methylcholanthrene (MCA)-induced sarcoma were used. After the animals were cachectic from their tumor, a central venous catheter was inserted. At the time of catheter insertion, the animals were randomized into two groups. Group I rats had the TB hindlimb amputated whereas Group II rats had the nontumor bearing (NTB) hindlimb amputated. After amputation, all animals were given TPN for 10 days then sacrificed. The results demonstrated that TB rats (Group II) had a significantly decreased tumor-free carcass weight in contrast to nontumor bearing rats (Group I). Furthermore, the TB animals had a significantly increased body weight gain after completion of TPN. This difference in body weight proved to be due almost entirely to the weight of the growing tumor. Compositional analysis revealed a significantly decreased protein stores and significantly increased fat stores of both the carcass and liver of the TB animals compared to those which the tumor had been resected. The results of the data suggest that TPN given to the sarcoma-bearing animal after tumor removal is better utilized for replenishing protein stores than when it is provided before removal of the tumor.