Predictive parameters of biologic behavior of early stage nonseminomatous testicular germ cell tumors

BACKGROUND: Thirty percent of patients presenting with clinical stage A nonseminomatous testicular germ cell tumors in fact have pathologic stage B disease. This pilot study was performed to determine whether DNA content and cell cycle analysis by flow cytometry and single-cell cytophotometry can improve clinical staging in these patients. METHODS: The orchiectomy specimens of 102 patients with clinical stage A disease were analyzed retrospectively using histopathologic classification, flow cytometry, and single-cell cytophotometry. All patients had undergone retroperitoneal lymph node dissection. RESULTS: The multivariate analysis in this group of patients resulted in the following model: If the primary tumor consisted of 100% embryonal carcinoma, the patient was classified as high risk for retroperitoneal metastasis. If the patient was found to have less than 100% embryonal carcinoma in the primary tumor, the percent of aneuploid tumor cells in S-phase as identified by flow cytometry was most predictive for pathologic stage. Using this approach, 91% of all patients with pathologic stage B, and 77% of the patients with pathologic stage A were correctly classified; test efficiency was 82%. CONCLUSIONS: These results demonstrate an improvement in clinical staging in this group of patients. This paradigm, developed from retrospective analysis, will be tested prospectively in consecutive patients to determine if it is clinically useful.