Population pharmacokinetics of cisplatin in patients with advanced ovarian cancer during intraperitoneal hyperthermia chemotherapy

The objective of this study was to determine the pharmacokinetic profile of total platinum administered by hyperthermic peritoneal perfusion (HPP) in 16 patients with ovarian cancer. The patients had a performance status of lIIalpha/b/c on the FIGO scale. They received 60, 80 or 100 mg of cisplatin. The percent of cisplatin remaining in the body after the peritoneum was emptied averaged 65% (41.7-85.4%). The average ratio between peritoneal drug concentrations and plasma concentrations was 73. A Bayesian estimation of individual phamacokinetic parameters was carried out using the non-linear mixed-effect modeling approach as implemented in the NONMEM computer program. A two-compartment model with an additional peritoneal cavity compartment was used to fit the data. Large interindividual variability of the pharmacokinetic parameters occurred The maximum platinum concentration in plasma was reached between 1 and 1.5 hours after the beginning of administration; it ranged from 0.37 to 1.7 microg/ml (1.9 to 8.72 microM). The elimination half-life was 80 hours (48-152 hours and the area under the plasma concentration time curve normalized to a 100 mg cisplatin dose was 79 mg/liter x hours. The simultaneous fit of perfusate and plasma concentrations allowed us to estimate the percent of cisplatin that reached the systemic circulation at about 20%. At time infinity, the urinary cisplatin recovery accounted for only 20% of the administered dose. The results in this study showed that a high proportion of the cisplatin dose was absorbed by target tumor cells. In spite of the advanced disease of patients at the time of HPP, 37.5% of them were still alive three years after HPP (ie., 3-6 years after cancer diagnosis) and 12.5%, 7 years after HPP (i.e., 8 years after cancer diagnosis).

Peritonectomy combined with intraperitoneal chemohyperthermia in abdominal cancer with peritoneal carcinomatosis: phase I-II study

OBJECTIVE

To evaluate the feasibility and the tolerance of Peritonectomy Procedure (PP) combined with Intraperitoneal Chemohyperthermia (IPCH) in patients with peritoneal carcinomatosis, a phase I-II study has been realised from January 1997 to September 1998.

METHODS

Eighteen patients were included for peritoneal carcinomatosis from colorectal cancer (13), ovarian cancer (2), gallbladder cancer (1), gastric cancer (1) and peritoneal mesothelioma (1). Peritoneal carcinomatosis were mainly advanced disease (16 stage 3 and 4, 2 stage 2). All the patients underwent surgical resection of their primary tumor with PP as described by Sugarbaker and IPCH (with Mitomycin C, Cisplatinum or both). IPCH used in this study was a "closed sterile circuit" device with inflow temperatures ranging from 46 to 48 degrees C. IPCH was performed on the same day as PP (8118) or delayed (10/18).

RESULTS

Significant down-staging of peritoneal carcinomatosis was achieved for 16 patients. One patient died postoperatively, while the morbidity rate was 6/18 (long postoperative ileus, grade 3 leucopenia and anastomotic leakage).

CONCLUSIONS

Combination of PP and IPCH could achieve significant tumoral volume reduction in peritoneal carcinomatosis. This aggressive treatment must be employed selectively because of its morbidity. Larger phase III studies are now needed.