Germ cell tumors (GCTs) most often arise in the gonads but some develop extragonadally. The aim of this study was to examine sex- and race-specific trends in incidence and survival of gonadal (GGCTs) and extragonadal GCTs (EGCTs) in the US from 1973 to 2007. We also examined the topographic distribution of EGCTs by race and sex. We estimated age-specific and age-standardized incidence rates and 5-year relative survival rates (RSR) of GCTs using the Surveillance, Epidemiology, and End Results (SEER) Program (SEER 9 registries). GCTs and their topographic sites were identified using ICD-O morphology and topography codes. Of 21,170 GCTs among males, 5.7% were extragonadal (whites 5.5%; blacks 16.3%). Of 2,093 GCTs among females, 39.3% were extragonadal (whites, 36.9%; blacks 51.0%). The incidence of GGCT was much higher among white (56.3/1,000,000) than black males (10.0/1,000,000) while there was no difference in incidence between white and black females (3.2/1,000,000). The rates of EGCT among men and women of both races were similar (range:1.9 – 3.4/1,000,000). The most frequent extragonadal sites were mediastinum among males and placenta among females. The 5-year RSR of testicular GCT was higher among whites (97%) than blacks (90%), as was the 5-year RSR of ovarian GCT (whites, 92%; blacks 85%). In general, the 5-year RSRs of EGCTs were lower than the 5-year RSRs of GGCTs. The different incidence trends of GGCTs and EGCTs and distinct age-specific incidence patterns by anatomic site of EGCTs suggests that GGCTs and EGCTs may have different etiologies.

Genetic variations in inflammation and its related subpathway components are keys to the development of lung, colorectal, ovary, and breast cancer, including SH2B3, which is associated with lung, colorectal, and breast cancer.