Urological second malignant neoplasms in testicular nonseminoma survivors: a population-based analysis

Patients with testicular non-seminomatous germ cell tumors in the modern cisplatin-based chemotherapy era show favorable outcomes, yielding survivors exposed to increased risk of second malignant neoplasms. The carcinogenic effects of cisplatin were well established, and its side effects had shown close connections with the urinary system. The study aimed to evaluate how the characteristics of the primary testicular nonseminoma are associated with urological second malignant neoplasms and survival outcomes.

Using the Surveillance, Epidemiology and End Results database, standardized incidence ratios (SIR) for three major urological tumors including kidney, bladder, and prostate cancer were calculated for 10,734 patients with testicular nonseminoma from 1975 to 2016. The survival analyses were performed using the Kaplan-Meier method and log-rank test, risk factors for overall survival were determined by Cox regression.

We identified a total of 197 patients with secondary urological neoplasms. Patients with previous testicular nonseminoma had elevated risk of kidney cancer (SIR 2.13, 95% CI 1.59-2.79), bladder cancer (SIR 1.47, 95% CI 1.07-1.59), and decreased risks of prostate cancer (SIR 0.75, 95% CI 0.61-0.91) compared with the general population. Patients diagnosed with testicular nonseminoma had favorable prognosis with 10-year overall survival reaching 91.8%, and patients with urological second malignant neoplasms showed better prognoses than patients with other second malignant neoplasms (log-rank P < 0.001).

Testicular nonseminoma survivors showed higher risks of kidney and bladder cancer associated with chemotherapy and decreased risk of prostate cancer. The prognosis of urological second neoplasms was better than other tumor origins.