Extent of parietal peritonectomy does not change intraperitoneal chemotherapy pharmacokinetics

Purpose. To measure the clearance intraperitoneal mitomycin C and doxorubicin in patients having peritonectomy and analyze the impact of the extent of peritoneal resection on pharmacokinetics. Methods. A group of 15 patients with peritoneal carcinomatosis were submitted to cytoreductive surgery and heated intraperitoneal chemotherapy. Ten patients received mitomycin C and five, doxorubicin. Six patients underwent total parietal peritonectomy and nine had less-extensive peritonectomy. Pharmacokinetics were determined by sampling peritoneal fluid and blood. Drug concentrations over time, area under the curve ratios and the amount of drug recovered from the peritoneal cavity were calculated and compared between the groups. Results. The concentrations of mitomycin C over time in the peritoneal fluid and plasma were similar in five patients with total parietal peritonectomy as compared to five patients with less-extensive peritonectomy (P = 0.5350 and 0.6991; Mann-Whitney test). Mitomycin C area under the curve ratio in total peritonectomy patients was 20.5 and 25.7 in patients with less-extensive peritonectomy. The difference in total amount of drug recovered from the peritoneal cavity was not significant (30.6+/-6.188% versus 22.6+/-3.84%, P = 0.095). In the studies with doxorubicin, one patient underwent total parietal peritonectomy with similar pharmacokinetics to four patients submitted to partial peritonectomy. Conclusions. The extent of parietal peritoneal resection did not affect the pharmacokinetics of intraoperative intraperitoneal chemotherapy. The pharmacological barrier between the abdominopelvic cavity and plasma is not directly related to an intact peritoneum.