Cancer superimposed on adult T-cell leukemia.

Forty-three patients with adult T-cell leukemia (ATL), admitted to the hospital from 1982 to 1987, were studied. Five of those were found to have additional cancer; two of the five had two additional kinds of cancers besides ATL. During the same period, in contrast, the authors encountered only three patients with some superimposed cancer among 155 cases of hematologic malignancies which had no association with human T-cell lymphotropic virus type I (HTLV-I). These facts strongly suggest that HTLV-I infection is not only associated with ATL, but it is likely to increase the incidence of other types of malignancy as well.