Liposarcoma Produced by 1:2-Benzpyrene

Abstract

We have recently described (1) the production of fibrosarcoma, rhabdomyosarcoma, and leiomyosarcoma by means of the subcutaneous injection of 1:2:5:6-dibenzanthracene in mice, rats, and rabbits. We wish to emphasize further the diverse character of the tumors produced by the cancerigenic hydrocarbons by describing five liposarcomas which we have produced with 1:2-benzpyrene in a mouse and four guinea-pigs, respectively. We know of no previous reports of the experimental production of liposarcoma by any means, with the exception of an example published by Bullock and Curtis (2), which was produced in the liver of an albino rat by the action of the Cysticercus fasciolaris. Liposarcoma in a Mouse Mouse No. 911, a white female of the Marsh strain, was injected with 1:2-benzpyrene on Jan. 20, 1935, when she was 128 days old. A one per cent solution of the benzpyrene in lard was used, 0.2 c.c. being injected subcutaneously in the anterior axillary line, midway between the axilla and the groin on each side. A tumor was first noted at the site of injection on the right side eighty-eight days later. It grew rapidly to reach a diameter of 3 cm. The mouse was then killed. The tumor was firm and white, and infiltrated the tissues of the chest wall. Portions of it were fixed in Zenker9s fluid, and the remainder reserved for transplantation. No metastases were found in the course of the autopsy. Twenty-four mice that were litter mates of mouse No. 911 were given subcutaneous inoculations of the tumor. It grew well in these new hosts, as shown by Chart I, which records its progress in 8 of the mice. Eighteen of the original 24 mice were alive two weeks after inoculation. Fourteen of these bore tumors and 4 did not. In 3 mice spontaneous recession of the tumor took place. The other tumors grew fairly rapidly, reaching an average diameter of 1.3 cm. six weeks after inoculation. Two of the tumors were ulcerated at this time. Their tumors being large, the mice were sacrificed a week later, and a section taken for histological study from one of the transplants. Further transplantation was not attempted.