Intraperitoneal treatment using Taxol is effective for experimental peritoneal carcinomatosis in a rat model

Following resection of colorectal carcinoma, a considerable local recurrence rate within the previous tumor bed or at the peritoneal site remains an unsolved problem. Currently, there are no established protocols for the treatment or prevention of peritoneal carcinomatosis. Taxol showed benefit in patients with advanced tumor growth, in particular, gynecological carcinomas. Taxol was used to test whether it can either prevent or treat peritoneal tumor growth derived from colon carcinoma. In rats divided in 3 groups, peritoneal carcinomatosis was induced by tumor cell transfer: Taxol (170 mg/m(2)) was given i). directly (group A); ii). on days 5, 10, 15 postoperatively (representing early administration; group B), or iii). as late intraperitoneal (i.p.) chemotherapy (15, 20, 25 days following surgery; aiming for reduction of a manifest peritoneal carcinomatosis; group C) into the abdominal cavity. Tumor growth was quantified by tumor weight of the greater omentum and the mesenteric site, number of detectable tumor lesions, occurrence of hepatic and pulmonary metastases and the amount of ascites. Taxol was highly effective in preventing or reducing i.p. tumor spread when the drug was given directly or within a short time interval after tumor cell implantation (groups A and B), whereas no significant antineoplastic potential was found in the treatment of an established peritoneal carcinomatosis. In conclusion, Taxol appears to be a promising chemotherapeutic agent to be investigated in further detail with possible potential for a later human phase-I trial in peritoneal carcinomatosis.