Reticular Neoplasms Induced in DBA/2 and CBA Mice by Intraperitoneal Injections of Mineral Oil2

Abstract

A total of 1.5 ml of mineral oil, Primol D, was given in 3 intraperitoneal injections into 36 DBA/2 and 12 CBA female mice, most of which survived for more than 15 months. Small granulomatous nodules containing oil droplets developed intraperitoneally in all mice. Oil droplets were also found in the liver, spleen, and lungs. Of the 36 DBA/2 mice, 15 (42%) developed reticulosarcomatous growths of Type A of Dunn in some of the peritoneal nodules. In addition, leukemic infiltrations of varying degrees of severity were found in the liver and less frequently in other organs. Only one mouse had a definite myeloid leukemia; 2 mice showed incipient myeloid leukemia (or myeloid hyperplasia), one associated with plasma cellular infiltrations. Three mice developed plasma cell leukemia with some admixture of myeloid cells, and 2 developed lymphocytic leukemia, the latter considered spontaneous. Thus, a total of 21 of 36 DBA/2 mice (58%) responded in some way or other to the deposited mineral oil. In the 12 CBA animals one reticulum cell sarcoma, probably of Type B of Dunn and one most likely spontaneous lymphocytic leukemia were found. Successful transplantations from 3 reticulum cell sarcomas and from the myeloid leukemia maintained the morphology of the primary hosts. The results are compared with those obtained with injection of mineral oil into BALB/c mice, and the importance of the genetic constitution of the mice is emphasized. The multicentric development of the reticulosarcomatous growths in the peritoneal nodules and the potentiality of the hepatic perivascular reticulum to transform into various types of reticular cells under the influence of the mineral oil are suggested.