In vitro chemosensitivity test for human genito-urinary tumors using collagen gel matrix

Although the aim of chemosensitivity tests is to predict the efficacy of anticancer agents for individual patients, no generally accepted assay has been established.

A chemosensitivity test was conducted for solid tumors with an organ culture system using collagen gel matrix (CGM). Seventy-five samples of transitional cell carcinoma (TCC), 20 of germ cell tumor (GCT) and 13 of renal cell carcinoma (RCC) were used for the chemosensitivity test, and 20 patients were treated with anticancer drugs on the basis of the test results.

Positive rates of anticancer drugs for the 75 TCC samples were 64.9% for carboplatin, 63.4% for cisplatin, 32.1% for etoposide, 19.7% for THP-adriamycin, 16.7% for vinblastine, and 12.3% for methotrexate, indicating that positive rates of the latter three agents consisting of an MVAC regimen were unexpectedly low. The GCT had higher positive rates than the other cancers while RCC had the lowest. In 20 eligible patients (seven patients with bladder tumors and 13 with GCT), the true positive and true negative rates were 42% (5/12) and 75% (6/8), respectively, and the sensitivity and specificity were 71% (5/7) and 46% (6/13), resulting in a 55% (11/20) accurate predictive value.

Although predictive accuracy was moderate when combination chemotherapy was used, information about chemosensitivity may have some beneficial effect on the treatment of patients with invasive bladder cancer or advanced GCT, because insensitive drugs detected by the test could be deleted or replaced with more sensitive ones.