gimeracil and Peritoneal-Neoplasms

The response of gastric cancer with peritoneal dissemination to systemic chemotherapy may be negatively affected by poor drug delivery due to the blood-peritoneal barrier. However, S-1 has been reported to be effective. We examined the pharmacokinetics of S-1 in 14 patients who had gastric cancer with peritoneal dissemination. S-1 was given from the morning of the day before surgery to the morning of surgery. Concentrations of 5-fluorouracil (5-FU) and gimeracil (CDHP) were measured in the serum, ascites, disseminated peritoneal nodes, and normal peritoneum. There was a strong correlation between 5-FU and CDHP concentrations in peritoneal tissues. The concentrations of 5-FU and CDHP in the serum were similar to those in ascites. The concentration of 5-FU was significantly higher in disseminated nodes than in the normal peritoneum. After administration of S-1 to gastric cancer patients with peritoneal dissemination, 5-FU and CDHP in the serum linearly pass through the peritoneum and enter the ascites. High concentrations of 5-FU selectively penetrate disseminated peritoneal cells.

Topics: Adult; Aged; Antimetabolites, Antineoplastic; Biological Availability; Drug Combinations; Female; Fluorouracil; Humans; Lymph Nodes; Male; Middle Aged; Oxonic Acid; Peritoneal Neoplasms; Peritoneum; Pyridines; Stomach Neoplasms; Tegafur

The optimum dose of TS-1 for the treatment of peritoneally disseminated gastric cancer in a patient with chronic renal failure undergoing chronic dialysis was estimated by monitoring the blood concentrations of 5-FU and gimeracil (CDHP) [therapeutic drug monitoring (TDM)] during administration of TS-1. Immediately after dialysis, 50 mg or 40 mg of TS-1, corresponding to 50% and 40% of the standard dose (100mg for this patient), respectively, was administered orally once a day every other day, and TDM was conducted. Compared with the pharmacokinetic parameters of 5-FU at the time of the initial administration of 50 mg or 40 mg of TS-1 and that of cancer patients with normal renal function, the AUC shown in the administration of 40 mg was equivalent to that observed with a single safe dose of 100 mg in patients with normal renal function. Based on this observation, the daily TS-1 dose was set at 40 mg in this patient, and TS-1 treatment was started after confirming the absence of the accumulation of 5-FU or CDHP during repeated administrations. In this treatment protocol, TS-1 was administered 11 times at a daily dose of 40 mg every other day immediately after dialysis, followed by a rest. This .administration schedule was defined as one course. Under these conditions, the patient was treated on an outpatient basis, and the treatment could be safely continued without the development of any severe adverse events, such as myelosuppression.

Topics: Adenocarcinoma; Adult; Antimetabolites, Antineoplastic; Area Under Curve; Drug Administration Schedule; Drug Combinations; Drug Monitoring; Fluorouracil; Gastrectomy; Humans; Kidney Failure, Chronic; Male; Oxonic Acid; Peritoneal Neoplasms; Pyridines; Renal Dialysis; Stomach Neoplasms; Tegafur

TS-1(S-1) has been developed as a new oral anticancer drug based on the biological modulation of 5-fluorouracil. We treated a patient with highly advanced gastric carcinoma with a new combination chemotherapy of S-1 and low-dose cisplatin. Remarkable tumor reduction was observed after two cycles of this therapy in the primary tumor and metastatic lymph nodes, and the ascites disappeared. This was concluded to be a partial response. The only adverse effect was skin pigmentation of the fingers (grade 1), leading to early timing of operation after chemotherapy. The gastric tumor showed evident invasion to the serosa. Lymph nodes around the stomach were swollen. Peritoneal dissemination was also recognized in the omentum and mesocolon. Total gastrectomy with regional lymph node dissection was performed. Disseminated tumors were all resected. Histological examination showed that no tumor cells were detected in the gastric primary lesion, metastatic lymph nodes or disseminated peritoneal tumors, suggesting pathological complete remission. It was suggested that this regimen could be a potent combined therapy for the treatment of patients with highly advanced gastric carcinoma, and it could be useful as neoadjuvant chemotherapy. Further studies are necessary to evaluate the efficacy of this therapy.

Topics: Adenocarcinoma; Antimetabolites, Antineoplastic; Antineoplastic Combined Chemotherapy Protocols; Cisplatin; Drug Combinations; Gastrectomy; Gastroscopy; Humans; Male; Middle Aged; Neoadjuvant Therapy; Oxonic Acid; Peritoneal Neoplasms; Pyridines; Stomach Neoplasms; Tegafur; Tomography, X-Ray Computed; Treatment Outcome