Effects of Krebs-2 carcinoma on the lipide metabolism of male Swiss mice.

Total body composition of mice bearing Krebs-@ carcinoma transplanted subcuta neously was studied at several times during the course of tumor growth. Adult male Swiss mice, averaging 38 gin. in weight, sustained a profound fat loss during growth of Krebs-@ tumor. Fat depletion occurred in three stages. The first stage, involving loss of approximately 50 per cent of the lipide of the animal, occurred by 7 days after transplantation, before the tumor had reached appreciable size. The second phase was one of steady state in which no further fat loss occurred despite active tumor growth. This stage lasted approximately from day 7 to day @8. Premortally, the tu mor-bearing animal lost another substantial quantity of fat. The first stage fat loss has been reproduced with nonviable preparations from tumor. The possible nature of the lipolytic factor is discussed.