Subsequent malignancies in patients irradiated for testicular tumours

Abstract

A total of 897 patients received radiotherapy in Scotland for tumors of the testis between 1950-1969. A total of 299 patients who died within 2 yr of treatment, and a further 51 patients with inadequate follow-up data, were excluded from a survey of the incidence of 2nd tumors. A total of 547 patients with a mean follow-up of 15.4 yr were included in the study. Fifty-one 2nd and six 3rd malignancies were found. The observed incidence is significantly higher than expected (ratio 1.87; P < 0.001), both in the irradiated sites (ratio 1.94; P < 0.05) and in unirradiated sites (ratio 1.99; P < 0.01). These patients have a higher incidence of 2nd testicular tumors (ratio 23.1; P < 0.001). Analysis of the incidence of new malignancies in successive quinquennia after irradiation shows a significantly higher incidence in 2 periods. Within 5 yr the greater incidence (P < 0.05) is due mainly to the occurrence of 2nd testicular tumors. In the period 15-19 yr after irradiation the higher incidence (P < 0.01) is accounted for by tumors arising in the urinary and gastrointestinal tracts. The increased risk of developing a 2nd cancer is low and there was no observed increase in radiation-related leukemia.