Subsequent neoplasia in chronic lymphocytic leukemia.

We performed a retrospective analysis of all 102 cases of chronic lymphocytic leukemia (CLL) treated by the Hematology Service of the University of Manitoba from Jan 1, 1955, to April 1, 1974. The incidence of secondary cancer was compared with that in the Cancer Registry population of Manitoba of the same age and sex distribution. The risk of all cancers developing in patients with CLL was threefold that for the age- and sex-matched population, eightfold for skin cancers, and twofold for all cancers excluding skin cancer.