Chronic Myelosis Following the Use of Thorotrast

Following hepatolienography which was carried out in a woman aged 52 in 1931, for a tumor of the right kidney which was removed at operation, chronic myelosis developed in 1954. This was remarkable for the absence of splenomegaly, a relatively mild course and a paradoxic reaction to x-ray irradiation of the spleen, when instead of the expected decrease there was a doubling in the number of leukocytes. A causal relationship of myeloid leukemia to the thorotrast administered 23 years previously cannot be excluded.