[Clinical trials of the subrenal capsule assay]

Clinical trials of 4-day subrenal capsule assay (SRC assay) were carried out. One hundred and forty-one cases were investigated in order to evaluate the clinical utility of the assay. A total evaluability rate of 81.0% and a response rate of 36.5% were obtained in the SRC assay. The overall predictive accuracy between the tumor sensitivity of the assay and the clinical response was 82.1%. The percentage inhibition of %DNA/protein content of the implanted tumor, as a new predictor of the tumor growth inhibition, also indicated a good prediction rate for the assay. Correlation between the sensitivity test and the end results after chemotherapy in cases of inoperable gastric cancer classified as stage IV was investigated, retrospectively. Comparison of the survival curves between the patients treated with sensitive agents and those with insensitive agents exhibited a significant advantage for the former (p less than 0.01). These results suggest the utility of the SRC assay for clinical use, but histological studies exhibited certain limitations of this assay due to the existence of early host rejection of the implanted tumor. The utility of the SRC assay should be finally evaluated using more histological assessments and clinical trials.