Influence of various fatty acids on tumour growth in total parenteral nutrition.

The aim of parenteral nutrition in tumour patients is to offer an alternative nutritional support to the patient without accelerating the growth of the tumour. For this purpose we fed a total of 100 rats, divided into five groups of 20 animals each (10 with and 10 without tumours), for a total period of 15 days with various nutritional regimes. Group 1 received glucose, group 2 long-chain triglycerides, group 3 medium-chain triglycerides (MCT), group 4 omega-3 fatty acids, and group 5 an oral diet. On the 10th day the Yoshida sarcoma in its ascites form was implanted into the tumour-bearing rats. In animals receiving MCT or omega-3 fatty acids tumour growth was considerably smaller than in the other groups (group 1 vs. groups 3 and 4; p < 0.05). Unfavourable effects of the administration of these fatty acids on the general condition of the animals were not observed [muscle nitrogen content (mg/kg body weight): MCT = 82.3, omega-3 fatty acids = 65.25]. The impulse cytophotometric measurements did not demonstrate any influence on the pattern of cell division (p > 0.05). We think that modulation of the immune system by feeding with MCT or omega-3 fatty acids was responsible for the reduced tumour growth in relation to the other groups. The extrapolation of these results to the clinical situation, however, may not be possible.