Risk of carcinomas (other than those of breast, thyroid, or skin) was four-fold higher than that expected (95% CI, 3.1 to 5.1). An elevated RR appeared 5 to 10 years after the initial cancer (SIR = 5.3) and decreased with time thereafter, though it remained significantly elevated after 20 years (SIR = 2.8). The most common sites of the carcinomas were head and neck (mostly parotid gland), gastrointestinal tract, female genitourinary tract, and kidney. Radiation treatment was associated with increased risk of carcinoma at all sites, with the exception of the genitourinary tract, but it was most pronounced for head and neck carcinomas (SIR = 18.5 for patients who received radiotherapy versus SIR = 2.3 for those who did not). Risk was elevated for all primary childhood diagnostic groups in the cohort, but it was highest for survivors of neuroblastoma (SIR = 24.2) or soft tissue sarcoma (SIR = 6.2).