Prognostic implications of the expression of erbB2, topoisomerase II alpha and thymidylate synthase in metastatic gastric cancer after fluorouracil-based therapy.

OBJECTIVE: This retrospective study aimed to ascertain the expression of erbB2 in relation to topoisomerase II alpha (T2 alpha) and thymidylate synthase (TS) markers in 30 consecutive metastatic gastric cancer patients with a specimen available for study. METHODS: All patients had been entered on consecutive chemotherapeutic clinical trials that were all 5-fluorouracil based. The specimens were evaluated by fluorescence in situ hybridization to ascertain erbB2 and T2 alpha gene amplification, and by immunohistochemical staining for T2 alpha and TS protein expression. RESULTS: erbB2 amplification was detected in 16.7% of specimens, with co-amplification of the T2 alpha gene in 40%, and 44% had undetectable TS protein expression. Kaplan-Meier survival curves showed significantly prolonged overall survival in patients with erbB2 and T2 alpha gene amplification, T2 alpha protein overexpression and absence of TS protein expression (P = 0.0011, P = 0.0048, P = 0.0061 and P = 0.0267, respectively, by log rank test). There was a positive correlation between erbB2 amplification and T2 alpha amplification, T2 alpha protein overexpression, and a trend towards absence of TS expression (P = 0.0001, P = 0.003 and P = 0.066 by Fisher's exact test). CONCLUSION: High dose fluorouracil/leucovorin-based chemotherapy may have the potential to reverse the adverse effects resulting from erbB2 gene amplification in gastric cancer.

A phase I study of weekly docetaxel, 24-hour infusion of high-dose fluorouracil/leucovorin and cisplatin in patients with advanced gastric cancer.

OBJECTIVES: To determine the maximum-tolerated dose (MTD) and dose-limiting toxicity (DLT) of both docetaxel and 5-fluorouracil (5-FU) when administered weekly in a regimen of docetaxel, 5-FU/leucovorin and cisplatin (DFLP) for 2 consecutive weeks every 3 weeks. PATIENTS AND METHODS: A total of 31 patients with chemo-naive, advanced adenocarcinoma of the stomach were enrolled in the study. Cisplatin and leucovorin dosages were fixed throughout the study at 30 and 300 mg/m2, respectively. 5-FU dosage was fixed at 1,600 mg/m2 while docetaxel was evaluated at weekly 1-hour infusion dosages of 30, 40 and 50 mg/m2 to determine the MTD. Cisplatin, 5-FU and leucovorin were administered together as a 24-hour continuous infusion following docetaxel. Weekly 5-FU dosages of 1,600, 2,000 and 2,400 mg/m2 were then evaluated after setting the docetaxel dosage at the MTD. RESULTS: A total of 95 chemotherapy cycles were administered, with a median of three cycles per patient. The MTD of docetaxel was defined at 40 mg/m2. At a docetaxel dosage of 50 mg/m2 per week, the dose-limiting events of grade 4 febrile neutropenia and grade 3 hypomagnesemia occurred. With fixation of docetaxel to 40 mg/m2, the DLT for 5-FU was found at 2,400 mg/m2 per week. This incurred grade 4 neutropenia such that the MTD of 5-FU was defined at 2,000 mg/m2. Grade 3/4 neutropenia occurred in 14 patients (45%), with 2 patients developing febrile neutropenia. Grade 2 and 3 hypomagnesemia and hypokalemia occurred in 9 (41%) and 4 (18%) patients, respectively, of the first 22 patients treated with a 24-hour infusion of cisplatin and 5-FU/leucovorin immediately following docetaxel. Following a change in the cisplatin administration schedule to a 3-hour infusion after 5-FU/leucovorin infusion, no such complications were observed in 9 subsequently treated patients. Grade 2 diarrhea was recorded in 11 patients (35%). Grade 2/3 asthenia occurred in 9 patients (30%), which resolved after correction of electrolyte disorders. Twenty-six patients were assessable for response analysis. There were 2 (7.8%) complete and 14 (53.8%) partial responses, with the overall response rate being 61.5% (95% confidence interval, 41.5-81.6%). Responses were observed at all dose levels. CONCLUSION: Two consecutive weeks of DFLP infusions every 3 weeks appear to be an active regimen with a tolerable toxicity profile in advanced gastric cancer. For further phase II studies, the recommended dose for this combination is 40 mg/m2 of docetaxel and 2,000 mg/m2 of 5-FU per week.