PURPOSE

Few studies have quantified differences in histology and implications for survival between male children and adults with germ cell tumors (GCT). We evaluated these differences and associations with cancer-specific survival (CSS) using Surveillance, Epidemiology, and End Results (SEER) cancer registries.

METHODS

SEER (1988-2016) was used to identify male patients 0 to 40 years of age diagnosed with seminoma and nonseminomatous GCT (NSGCT). Demographic and tumor characteristics were tabulated with histology distributions compared by age group (0-4, 12-18, 19-40 years old). CSS was evaluated in multivariable Cox proportional hazards regression models.

RESULTS

Among 27,204 patients identified, 1,538 (5.7%) were pediatric (0-18 years). Seminoma (54.3%) predominated in adult patients (ages 19-40). Among 0 to 4 years-old, yolk sac tumor (71.2%) and teratoma (21.5%) were most common. Mixed GCT (52.7%) was most prevalent among 12 to 18 years-old with seminoma, embryonal, and teratoma occurring in 12 to 15% each. Relative to pediatric patients, adult patients had similar CSS for seminoma but worse CSS for NSGCT on Kaplan-Meier curves with 9 years mean follow-up. Choriocarcinoma and yolk sac tumors carried the worst prognosis relative to seminoma for both children (HR 5.7 and HR 11.1, respectively, both P < 0.01) and adults (HR 4.6 and HR 4.6, respectively, both P < 0.01) adjusted for stage.

CONCLUSION

Histology of GCTs vary by age with yolk sac tumors and teratoma predominating for male patients 0 to 4 years, mixed GCT for 12 to 18 years, and seminoma for 19 to 40 years. Pediatric patients with NSGCT had higher CSS than their adult counterparts. Mixed GCT represented an increasing proportion of GCT over the study period. Age, stage, and histology impact CSS in both pediatric and adult populations.