Predictive parameters in biologic assessment of low-stage retroperitoneal lymph-node dissection.
In all, 30% of patients felt to have clinical stage A nonseminomatous testis cancer in fact have pathologic stage B disease. Although patients with clinical stage A nonseminoma currently enjoy a very high change for cure, a better assignment of therapy at diagnosis could lead to an overall decrease in the morbidity of treatment. This study analyzed orchiectomy specimens from 102 patients with clinical stage A nonseminomatous testis cancer, all of whom underwent pathologic staging via retroperitoneal lymph-node dissection (RPLND). Various parameters of the orchiectomy specimen were analyzed to determine whether or not clinical staging could be improved on the basis of these factors. Statistical analysis resulted in the following model. If the orchiectomy specimen consisted of 100% embryonal carcinoma the patient was classified as being at high risk for retroperitoneal metastasis. In the absence of this finding the aneuploid cell line as determined by flow cytometry was considered. If the percentage of aneuploid cells in the S phase was less than 29% the patient was felt to be at low risk for retroperitoneal metastasis. If this percentage was greater than 29% the patient was classified as being at high risk. Using this paradigm, 77% of pathologic stage A patients and 91% of pathologic stage B patients were correctly classified. The test efficiency was 82%. This pilot study resulted in an interesting model that should be tested prospectively in consecutive patients to determine whether it is clinically useful.