Objectives: To determine whether the clinical course or the histopathologic risk factor assessment of the secondary tumor justifies early detection of the premalignant testis, since only 5% of contralateral testicular biopsies in the case of a testicular tumor reveal a testicular intraepithelial neoplasia (TIN).
Methods: From 1975 to 1997, 30 patients with bilateral germ cell tumors were treated; histologic and clinical data were available in all patients. In 12 patients, histopathologic re-evaluation and immunohistochemical staining of both tumors was performed for risk factor analysis.
Results: At the time the primary tumor was diagnosed, the mean patient age was 28 years. The metachronous secondary tumors were detected after a mean of 5.6 years. Seminoma was the predominant histologic finding in primary (53%) and secondary (56%) tumors. Eighty-three percent of patients had clinical Stage I (Lugano classification) disease at the diagnosis of the secondary tumor and 17% Stage II. Only 3 of 12 secondary tumors showed vascular invasion. The proliferation analysis (MIB-I score) showed a mean proliferation rate of only 34% within the primary and 26% within the secondary tumors.
Conclusions: The results of our study show that the low clinical stage and good outcome associated with a histologic low-risk score of the secondary tumor does not mandate contralateral biopsy to detect TIN at the time of diagnosis of the first tumor.