The present study was designed to evaluate whether daily insulin treatment for weight-losing cancer patients attenuates the progression of cancer cachexia and improves metabolism and physical functioning in palliative care. One hundred and thirty-eight unselected patients with mainly advanced gastrointestinal malignancy were randomized to receive insulin (0.11 +/- 0.05 units/kg/d) plus best available palliative support [anti-inflammatory treatment (indomethacin), prevention of anemia (recombinant erythropoietin), and specialized nutritional care (oral supplements + home parenteral nutrition)] according to individual needs. Control patients received the best available palliative support according to the same principles. Health-related quality of life, food intake, resting energy expenditure, body composition, exercise capacity, metabolic efficiency during exercise, and spontaneous daily physical activity as well as blood tests were evaluated during follow-up (30-824 days) according to intention to treat. Patient characteristics at randomizations were almost identical in study and control groups. Insulin treatment for 193 +/- 139 days (mean +/- SD) significantly stimulated carbohydrate intake, decreased serum-free fatty acids, increased whole body fat, particularly in trunk and leg compartments, whereas fat-free lean tissue mass was unaffected. Insulin treatment improved metabolic efficiency during exercise, but did not increase maximum exercise capacity and spontaneous physical activity. Tumor markers in blood (CEA, CA-125, CA 19-9) did not indicate the stimulation of tumor growth by insulin; a conclusion also supported by improved survival of insulin-treated patients (P<0.03). Insulin is a significant metabolic treatment in multimodal palliation of weight-losing cancer patients.
