Transplantable Lymphosarcoma I N Mice

Among the 100 tumors that have been induced in this laboratory during the past year by the injection of 1: 2 : 5: 6-dibenzanthracene into mice were three lymphosarcomata. Lesions of the lymphatic system, lymphoid leukemia and lymphosarcoma have not occurred as a genetic factor in the untreated mice of the pure inbred strains used, although apparently such strains are not uncommon or difficult to obtain by selective breeding. Slye, Korteweg, Mercier and Gosselin, MacDowell and Richter, Dobrovolskaia-Zavadskai'a, Furth and Strumia, and Furth, Seibold and Rathbone have described strains of mice with a genetic tendency to develop lymphadenosis. Furth, Seibold and Rathbone (1933), in studies on five lymphatic neoplasms occurring in the mice of their strains, have reviewed the literature on lymphadenosis in mice. The results of our own investigations add little to the knowledge of diseases of the lymphatic system that has'already been acquired through previous investigations (Slye, Richter and MacDowell, Potter and Richter, Furth, Seibold and Rathbone, Furth and Strumia, Mercier and Gosselin, Korteweg, Krebs and Faber), but since the three lymphosarcomata were induced tumors that arose at the site of an injection of dibenzanthracene and were studied as transplanted sarcomata and not as blood diseases, it is believed that a description of them is important. The first of these tumors was discovered in a mouse of the C3H strain that had been injected 75 days previously. Owing to the illness of the animal, the cyst which had formed around the injected oil and dibenzanthracene was removed and transplanted into a normal mouse of the same strain. Thirtytwo days later the implanted cyst had grown into a large tumor which, when studied in tissue cultures and in stained preparations, proved to be composed of lymphocytes. The number of this tumor was 172 and it has been transplanted through twelve generations into C3H strain mice during a period of 152 days. In every instance the transplanted tumor retained the characteristics of the primary lymphosarcoma. Tiny fragments of the tumor transplanted subcutaneously into normal young C3H strain mice grew to the size used for transplantation, 25 X 15 >(: 5 mm., within two weeks. From that time on the tumors rapidly increased in size (40 X 20 X 5 mm.) and led to the death of the host about a week later. The tumor proved to be strain specific; while it grew in every one of the Bar Harbor C3H strain mice into which it was transplanted, it failed to grow when implanted into mice of the A, BA or C:., strains. Macroscopically the tumor had a peculiar glistening appearance, quite unlike that of the majority of induced sarcomata. It was composed of rather