Animal models for the study of cancer-induced anorexia.

Walker carcinoma 256/B transplanted sc in CD-COBS rats induce a decrease of food intake when the tumor size is less than 5% of the body weight. This anorexia is accompanied by a decrease of the adipose tissue and, to a lesser extent, of muscular tissue. The mechanism involved in cancer-induced anorexia seems to be different from that of classic centrally acting anorectic agents. Among the drugs tested to counteract this anorexia only cyproheptadine shows a modest effect. Cyclophosphamide reduces tumor growth and prevents decrease in food intake. It is suggested that Walker carcinoma 256/B may be a useful animal model to study problems related to cancer-induced anorexia and cachexia.