Prevention and treatment of transitional cell carcinomatosis with intraperitoneal chemotherapy in a rat model.
OBJECTIVE
Tumor spillage from bladder perforation during transurethral bladder tumor resection or cystectomy risks seeding the peritoneum with transitional cell carcinoma. We determined the lowest effective mitomycin C dose to prevent tumor implantation and the potential efficacy of delayed therapy. Additionally, we investigated the effect of tumor debulking combined with intraperitoneal mitomycin C.


METHODS
Using our established murine model of intraperitoneal transitional cell carcinoma implantation mitomycin C was instilled at decreasing concentrations to find the lowest effective dose. To evaluate the effectiveness of delayed therapy mitomycin C was administered on day 3 or 7 after tumor implantation. Finally, surgical debulking of established tumors with or without mitomycin C was performed.


RESULTS
All control animals had disseminated carcinomatosis. The lowest effective intraperitoneal mitomycin C dose to prevent implantation was 0.3125 mg/m(2). Administration of mitomycin C on day 3 after instillation resulted in tumor-free status in 50% of the animals, although no rats were tumor-free when treated on day 7. Tumor debulking only for established disease cured 40% of the animals, whereas debulking combined with mitomycin C had a 100% cure rate.


CONCLUSIONS
Intraperitoneal mitomycin C prevents tumor growth after transitional cell carcinoma implantation. Delayed therapy is not as effective as immediate treatment but cure is still possible, particularly when combined with surgical debulking, in a rat model.
Abaza
Ronney
R
Department of Urology, Ohio State University Medical Center and James Cancer Hospital, Columbus and University of Toledo College of Medicine, Toledo, Ohio.
Miocinovic
Ranko
R
Keck
Rick W
RW
Selman
Steven H
SH
D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000627:therapeutic use*; D002295:Carcinoma, Transitional Cell / Q000188:drug therapy* / Q000517:prevention & control* / Q000601:surgery; D004195:Disease Models, Animal; D016685:Mitomycin / Q000627:therapeutic use*; D009366:Neoplasm Seeding; D051381:Rats; D011916:Rats, Inbred F344
D000903:Antibiotics, Antineoplastic; D016685:Mitomycin