The incidence of benzpyrene-induced sarcomas in alloxan-diabetic rats.

Analyses of data on the cause of death in human diabetic patients suggest a negative relationship between diabetes and cancer. The reports of Lynch (10), Joslin (8), Warren (13), and more recently Robbins and Tucker (11 ), on the cause of death in human cases of diabetes indicate a lower frequency of carcinoma than expected. The latter observed only 8.4 per cent of deaths from cancer in a group of 307 proved diabetics, who were autopsied, while 14.7 per cent of deaths from cancer were found in a control group of 2,800 non-diabetics. Warren (13), reported deaths due to cancer in 8 per cent, Joslin (8) in 10.6 per cent and Lynch (10) in less than 3 per cent of the diabetics. The decreased percentage of deaths from cancer could not be attributed to disparity in age between the diabetic and control groups, but no other factor was implicated. The experimental results obtained by Tannenbaum (12) and others on underfed and calorie-restricted mice suggest that the faulty carbohydrate metabolism or failure of diabetics to store glycogen might be a factor in the delayed onset or prevention of cancer. Recently, Young, Kensler and Seki (14) have reported that sarcomabearing mice exhibit an impairment in liver glycogen storage, which is similar to the defect seen in patients with diabetes mellitus. Goldfeder (6) showed earlier that the amount of glycogen in the transplanted tumor and in the livers of tumorbearing mice and chickens was less than that found in analogous tissues of nontumor-bearing animals. Dunn and McLetchie (3), and Gomori and Goldner (7) have demonstrated that diabetes mellitus could be produced experimentally in the rat by intraperitoneal injection of alloxan. Duff and Starr (2) have shown that by an adjustment of the dose of the alloxan, some rats developed chronic diabetes and survived for several months. It has also been observed (9) that rats made diabetic with