Sensitivity to cisplatin determined by the histoculture drug response assay and clinical response of endometrial cancer.

This study investigated the value of the in vitro histoculture drug response assay (HDRA) for predicting the efficacy of chemotherapy in patients with endometrial cancer. Specimens were obtained from 115 patients with endometrial cancer treated at Keio University Hospital between 1994 and 2002. Tumor fragments were cultured on collagen sponge gel with cisplatin for 7 days, and cell viability was assessed. The cutoff value of the 50% inhibitory concentration of cisplatin was set at 23 microg/mL. Sensitivity of stage III or IV disease to chemotherapy was investigated, and differences of 5-year progression-free survival between patients with sensitive and resistant tumors were evaluated by the Kaplan-Meier method. Tumors were evaluable in 93.0% of patients (107/115). Among 38 patients in stages III or IV, 23 received chemotherapy containing cisplatin. Seven sensitive tumors did not recur, while recurrence/progression occurred within 6 months in 8/16 patients with tumors showing low sensitivity. Among stages III and IV patients, there was a significant difference of 5-year progression-free survival (P < 0.05) between those with tumors showing high or low sensitivity. Accordingly, the HDRA may predict the efficacy of chemotherapy for endometrial cancer.

Chemosensitivity testing of ovarian cancer using the histoculture drug response assay: sensitivity to cisplatin and clinical response.

Despite cytoreductive surgery and chemotherapy, the prognosis of advanced ovarian cancer is still poor. Predicting the chemosensitivity of tumors might improve the outcome. Therefore, we investigated the clinical value of the histoculture drug response assay for ovarian cancer. Tumor specimens were cultured for 7 days on collagen gel sponge in medium containing cisplatin, and the 50% inhibitory concentration was determined by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide assay. Then the in vitro sensitivity to cisplatin was compared with the clinical response and survival. Apoptosis of tumor cells was also investigated. Among 173 ovarian cancer patients, 164 were evaluable by the assay, and 29 patients had measurable lesions for which the clinical response could be determined. The 5-year survival rate was significantly higher in patients with chemosensitive tumors than in those with chemoresistant tumors when the cutoff value was set at a 50% inhibitory concentration of 25 microg/mL and the accuracy of the assay was 82.8% (24/29). As chemosensitivity to cisplatin became greater, the number of apoptotic cells also increased. This chemosensitivity assay may help predict the clinical response to cisplatin-based chemotherapy, thus improving the survival of ovarian cancer patients.