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.