Incidence patterns and trends of malignant gonadal and extragonadal germ cell tumors in Germany, 1998-2008

Abstract

Background: Malignant gonadal (GGCT) and extragonal germ cell tumors [GCT (EGCT)] are thought to originate from primordial germ cells. In contrast to well reported population-based data of GGCTs in males, analyses of GGCTs in females and EGCTs in both sexes remain limited.

Methods: In a pooling project of nine population-based cancer registries in Germany for the years 1998-2008, 16,883 malignant GCTs and their topographical sites were identified using ICD-O morphology and topography for persons aged 15 years and older. We estimated age-specific and age-standardized incidence rates.

Results: Among males, the incidence of testicular GCTs increased over time. In contrast, there was no increase in the incidence of EGCTs. Among females, rates of ovarian GCTs were stable, while rates of EGCTs declined over time. The most frequent extragonadal sites were mediastinum among males and placenta among females.

Conclusions: Our results underline different incidence trends and distinct age-specific incidence patterns of malignant GGCTs and EGCTs, as reported recently by several population-based registries. The differences suggest that GGCT and EGCT may have different etiologies.

Figure 1

Age-standardized incidence rates of gonadal and extragonadal germ cell tumors in Germany in males (solid line) and females (dashed line) aged 15 years and older, 1998–2008. Incidence rates of gonadal germ cell tumors in males illustrated by cases per 100,000. The interval on the left side displays the 95% confidence interval with average length, where averaging was performed all years.

Figure 2

Age-specific incidence rates of gonadal and extragonadal germ cell tumors in Germany in males (solid line) and females (dashed line) aged 15 years and older, 1998–2008. Incidence rates of gonadal germ cell tumors in males illustrated by cases per 100,000.