[Chemosensitivity testing using stem cell assay in urological and other malignancies].

We have attempted to grow several kinds of malignant tumors using human tumor stem cell assay. Formation of colonies in vitro was seen in 65 of 132 primary tumors (49%), including 25 of 41 (61%) uroepithelial cancers, 12 of 19 (63%) renal cancers, five of 12 (42%) testicular cancers, five of 21 (24%) gastrointestinal malignancies, five of 12 (42%) lung cancers, five of 11 (45%) hematopoietic malignancies and five of 16 (31%) other malignancies. Growth sufficient for in vitro chemosensitivity tests of CDDP developed from seven cases of uroepithelial cancer, three of them (43%) were sensitive to 2.5 micrograms X hour/ml of CDDP. The specimens from a metastatic testicular tumors that received several courses of PVB chemotherapy resulted in the resistance of the in vitro chemosensitivity test at a higher dosage of CDDP. Nine cases of renal cancer had sufficient growth for an in vitro chemosesitivity test of interferon. One of them was sensitive for alpha 2 type interferon. Three of seven cases were sensitive for alpha type of interferon. To predict clinical correlation, 19 patients were tested with the same drugs used in the in vitro chemosensitivity test. The predictability resulted in more than 60% of true positive, 91% of true negative and 86% of overall predictability.