Revisiting Sensitization Mechanisms in Cancer Thermochemotherapy : Does the Production of Radicals Hold the Key to Sensitization ?

5-fluorouracil combined with cisplatin and mitomycin C as an optimized regimen for hyperthermic intraperitoneal chemotherapy in gastric cancer

BACKGROUND AND OBJECTIVES

Optimized drug regimens for hyperthermic intraperitoneal chemotherapy (HIPEC) have not been standardized completely in patients with advanced gastric cancer (GC). We evaluated an optimized anti-tumor protocol comprising 5-fluorouracil (5-FU) combined with cisplatin (CDDP) and mitomycin C (MMC) in vitro for clinical use of HIPEC.

METHODS

The sensitivities of 5-FU, CDDP, or MMC, alone or in combination, using different drug concentrations, exposure times, and hyperthermic conditions (42°C) were determined in vitro by the CD-DST method using 3 different differentiated GC cell lines.

RESULTS

The tumor cell growth-inhibitory effect of 5-FU was concentration-dependent for all cell lines. In addition, 5-FU showed a hyperthermic sensitization effect at all drug concentrations for all cell lines. The appropriate concentration of each drug was 5-FU, 200 µg/mL; CDDP, 10 µg/mL; MMC, 2 µg/mL. Under hyperthermic conditions, most growth-inhibitory effects for each drug at 30 min was equivalent to 60 min of exposure; use of three drugs combined significantly inhibited growth compared with any of the drugs alone.

CONCLUSION

An appropriate in vitro intraperitoneal chemotherapy regimen for GC was combined use of 5-FU, CDDP, and MMC at 42°C for 30 min.

Feasibility and safety of hyperthermic intraperitoneal chemotherapy using 5-fluorouracil combined with cisplatin and mitomycin C in patients undergoing gastrectomy for advanced gastric cancer

BACKGROUND AND OBJECTIVES

We conducted a dose-finding study for 5-fluorouracil (5-FU) administered with cisplatin (CDDP) and mitomycin C (MMC) to find an improved regimen for hyperthermic intraperitoneal chemotherapy (HIPEC) for advanced gastric cancer (GC).

METHODS

The appropriate HIPEC regimen previously determined in vitro was 5-FU (200 µg/mL), MMC (2 µg/mL), and CDDP (10 µg/mL) at hyperthermic conditions (42°C) for 30 min. This was a clinical study to determine the recommended dose of 5-FU in combination with MMC and CDDP at 42°C for 30 min and to evaluate HIPEC safety in patients at high risk of developing peritoneal metastases following GC surgery.

RESULTS

Twelve patients were treated with surgery plus HIPEC using 5-FU at 0, 500, 750, and 1000 mg combined with MMC (10 mg) and CDDP (50 mg) in the perfusate (5 L). Dose-limiting toxicities did not develop until 1000 mg 5-FU was reached. Four patients experienced grade 1 or 2 adverse events. The recommended dose was 1000 mg 5-FU/5 L perfusate. Eight (66.7%) patients demonstrated no recurrence of peritoneal metastases; 5-year overall survival rate was 83.3%.

CONCLUSION

Gastrectomy and HIPEC with MMC, CDDP, and 5-FU is feasible, safe, and may protect against peritoneal metastasis following surgery for advanced GC.