Abstract. Docetaxel, cisplatin and 5-fluorouracil (DCF regimen) are currently applied as an effective combination treatment for various human malignancies; however, the efficacy of this regimen is impaired by severe adverse events associated with it. Therefore, better-tolerated regimens with comparable efficiency are required for patients with gastric cancer. To explore such possibilities, a phase-I clinical trial was performed to evaluate the safety and tolerability of a modified regimen replacing cisplatin and 5-fluorouracil with oxaliplatin and capecitabine, respectively (DOX program). The maximum-tolerated dose (MTD) and dose-limited toxicity (DLT) of capecitabine in this regimen were determined and a dose for subsequent phase-II clinical trials was identified. A total of 24 patients with advanced gastric cancer were sequentially enrolled in the present capecitabine dose-escalation trial. The patients were treated with docetaxel and oxaliplatin at fixed doses [75 and 100 mg/m 2 , respectively, intravenously, on day 1 (d 1 )], and with capecitabine at increasing doses (1,500, 2,000 and 2,500 mg/m 2 , per os, d 1-7 ). The MTD of capecitabine was 2,000 mg/m 2 (d 1-7 ), repeated every 21 days for at least two cycles. The most frequent DLTs for this regimen were leukopenia (15/24, 62.5%, all at grade-III/IV) and neutropenia (13/24, 54.2%, all at grade-III/IV), nausea (14/24, 58.3%, all at grade-III) and vomiting (13/24, 54.2%, all at grade-III). The effective rate of the DOX regimen was 75.0% (18/24). Based on the results, the combination of docetaxel (75 mg/m 2 , d 1 ), oxaliplatin (100 mg/m 2 , d 1 ) and capecitabine (2,000 mg/m 2 , d 1-7 ) is recommended for a future phase-II trial. While these doses for the DOX regimen were generally well tolerated, the efficacy of this modified regimen in patients with advanced gastric cancer remains to be further evaluated in subsequent phase-II trials.
IntroductionThe combination of docetaxel, cisplatin and 5-fluorouracil (DCF regimen) is currently used to treat human malignant diseases, including various progressive head and neck squamous cell carcinomas and advanced gastric and esophageal cancers (1,2). However, a high incidence of grade III/IV adverse events (AEs) resulting from these compounds works against the therapeutic efficacy of the DCF program (3). Therefore, optimizing the conventional DCF program may lead to a comparable efficacy, but with lower toxicity.The oral anti-cancer precursor molecule, capecitabine, is metabolized to 5-fluorouracil by thymidine phosphorylase (TP) in tumor cells, and its efficacy has been established in multiple clinical trials (4). It is more effective than (or at least not inferior to) 5-fluorouracil against a variety of malignant solid tumor types (5). Therefore, capecitabine may be ideal for replacing intravenous 5-fluorouracil. Oxaliplatin is a third-generation, platinum-containing anti-cancer drug and several clinical studies have reported that the one-year survival rate of patients who had received an anti-cancer regimen contain...