PREDICTIVE FACTORS FOR THE HISTOLOGIC NATURE OF RESIDUAL TUMOR MASS AFTER CHEMOTHERAPY IN PATIENTS WITH ADVANCED TESTICULAR CANCER

Objectives. To further improve the accuracy of the prediction of histo logic findings in the residual mass after chemotherapy in patients wit h metastatic germ cell tumors, various predictive factors were investi gated. Methods. A total of 23 patients with advanced testicular cancer underwent combination chemotherapy based on cisplatin following surgi cal removal of residual tumor mass in 20 patients and observation in 3 . Results. Complete fibrosis and/or necrosis was found in 6 (30%) oper ative specimens, teratoma in 3 (15%), and viable malignant tumor in 11 (55%). Three patients had no evidence of disease for a mean follow-up of 45 months. Five of the 6 patients and all of the 11 patients' resu lts could be predicted by a combination of 4 factors, including absenc e of teratomatous element in the primary tumor, greater than 85% tumor reduction rate after chemotherapy, normal alpha-fetoprotein and beta- subunit of human chorionic gonadotropin levels after chemotherapy, and actual half-life of alpha-fetoprotein less than 7 days. Among these f actors the tumor reduction rate and the actual half-life of alpha-feto -protein were the most important predictions statistically on multivar iate analysis. With the use of these criteria, the sensitivity rate, s pecificity rate, and overall predictive value of diagnosis for existen ce of viable malignant tumors were 83.3%, 100%, and 94.1%, respectivel y. Conclusions. By determining these factors it seems possible to avoi d surgical removal of the postchemotherapy residual mass in approximat ely 30% of patients with advanced metastatic testicular cancer.