Evaluation of the Histoculture Drug Response Assay as a Sensitivity Test for Anticancer Agents

To investigate whether the effects of anticancer agents are able to be predicted, the results of sensitivity tests on anticancer agents were compared with the results of preoperative chemotherapy. Biopsies were taken from 25 patients with esophageal cancer and 10 with gastric cancer, before chemotherapy, and the drug sensitivity was determined after culturing for 1 week. The chemotherapy consisted of low-dose cis-diamino-dichloroplatinum + 5-fluorouracil, and its clinical effect was determined after 3 or 5 weeks. Sensitivity was determined in 20 of the esophageal cancer patients and 8 of the gastric cancer patients, accounting for 80% of all the patients. Of the 11 patients judged to have sensitivity by the histoculture drug response assay (HDRA), 7 had a partial response, and of the 17 judged to have no sensitivity, 16 had a minor response or no change (NC). It was thus demonstrated that predictions of the effect of anticancer agents could be made with considerable accuracy using HDRA. The prognosis of the NC patients was poor, and distant metastasis, thought to be an adverse effect, soon appeared. From the viewpoint of both medical costs and patient quality of life, treatments other than preoperative chemotherapy should be selected for patients assessed to have NC. We believe that these sensitivity tests should be introduced clinically.