[Experimental study on intraperitoneal sequential MTX/5-FU therapy for peritoneal seeding in comparison with...

Area of Science:

• Oncology
• Gastroenterology
• Pharmacology

Background:

• Advanced gastric carcinoma frequently metastasizes to the peritoneum.
• Intravenous sequential methotrexate (MTX)/5-fluorouracil (5-FU) is a potent chemotherapy regimen.
• Intraperitoneal chemotherapy is proposed for localized peritoneal disease.

Purpose of the Study:

• To experimentally confirm the efficacy of intraperitoneal sequential MTX/5-FU chemotherapy.
• To compare intraperitoneal versus intravenous administration for gastric cancer peritoneal metastases.
• To evaluate the side effects of different administration routes.

Main Methods:

• A peritoneal seeding model was established in nude mice using the human gastric cancer cell line MKN-45.
• Mice were treated with intraperitoneal (i.p.) or intravenous (i.v.) MTX/5-FU on days 7, 14, and 21 post-implantation.
• Tumor burden, nodule counts, and body weight changes were assessed on day 35.

Main Results:

• Intraperitoneal MTX/5-FU significantly reduced peritoneal metastatic nodules compared to i.v. administration (0.41 vs. 5.3 nodules).
• Omental tumor weight was significantly lower in the i.p. group (0.051 g) versus the i.v. group (0.140 g).
• Mice receiving i.p. chemotherapy experienced less body weight decrease, indicating reduced toxicity.

Conclusions:

• Intraperitoneal sequential MTX/5-FU therapy demonstrates superior efficacy over intravenous administration for gastric cancer peritoneal seeding and micrometastases.
• Intraperitoneal administration of MTX/5-FU resulted in milder side effects compared to the intravenous route.
• This study supports the potential of intraperitoneal chemotherapy for managing peritoneal metastases in advanced gastric cancer.