To determine if utilization of surveillance or adjuvant chemotherapy has increased compared with that of adjuvant radiotherapy (ART) in clinical stage I seminoma (CSIS) and to estimate the impact of this utilization trend on secondary malignancies.

The National Cancer Data Base, a web-based data analysis tool was examined for first-course adjuvant therapy management in CSIS from 2000 to 2008. We assessed the utilization in academic vs community practice settings and changes in tumor stage. We also estimated the number of secondary malignancies based on the change in practice.

There were 52,672 patients of testicular cancer diagnosed. Of those, 28,974 (55.0%) patients had seminoma with 22,210 (84.2%) patients classified as CSIS. Overall, 14,005 (65.4%), 6430 (30.1%), and 951 (4.4%) patients received ART, surveillance, and adjuvant chemotherapy (AC), respectively. In 2000, most patients received ART (71.7%), followed by surveillance (26.5%), and AC (1.9%). In 2008, the majority of patients still received ART (47.7%) but surveillance (39.6%) and AC (12.6%) totaled a larger proportion. We calculated that this ART utilization rate would lead to an additional 372 solid tumor cases per year, 40 years later, whereas the current surveillance rate would lead to 34 cases of secondary malignancy annually in the United States.

ART was the leading adjuvant management strategy for CSIS, but its share drastically decreased with a concomitant increase in surveillance and AC, particularly after 2004. These trends were similar in both academic and community settings. The current level of ART, although decreasing, may nevertheless lead to additional cases of solid cancer comparable with testicular cancer deaths.