Serum and intraperitoneal pharmacokinetics of cisplatin within intraoperative intraperitoneal chemotherapy: influence of protein binding

Intraperitoneal (i.p.) chemotherapy is a promising therapeutic method to improve the effectiveness of cisplatin in patients with ovarian cancer and peritoneum involvement. Intraperitoneal treatment can be intraoperatively performed just after a complete surgical resection of peritoneal tumor nodules. However, little is known regarding the pharmacokinetics of platinum during intraoperative i.p. chemotherapy (IIC). Serum and i.p. measurements of total and ultrafilterable platinum were performed to determined pharmacokinetic parameters in 11 consecutive patients who received a 2-h IIC with 50 mg/m cisplatin. Protein concentrations were determined in serum and peritoneal liquid at the same times. The cisplatin concentration required to kill OVCAR-3 human ovarian cancer cells and evaluation of cisplatin binding to proteins were determined in vitro. Platinum i.p. concentration decreased rapidly and quickly came under the cytotoxicity threshold (10 mg for 2 h). About 85% of i.p. and serum cisplatin was ultrafilterable during IIC. Platinum concentrations were closely related to protein concentrations. Due to the very low level of serum protein (almost 25 g/l), serum cisplatin binding during chemotherapy was very low (almost 25%), but increased with protein concentration recovery. These pharmacokinetic data show that a sufficient concentration to kill human ovarian cancer is not reached with a single i.p. bath containing 50 mg/m cisplatin for 2 h. A new protocol with a renewed bath and a higher cisplatin concentration is under investigation.

Consolidation and maintenance treatments for patients with advanced epithelial ovarian cancer in complete response after first-line chemotherapy: A review of the literature

Most patients with advanced epithelial ovarian cancer experience objective responses to paclitaxel/platinum-based chemotherapy, but responses are generally short-lived and the clinical outcome is still unsatisfactory. Therefore, the strategy to consolidate and to prolong the duration of response is very attractive. Different consolidation or maintenance treatments have been attempted, such as whole abdomen radiotherapy, intraperitoneal chromic phosphate, radioimmunotherapy, intraperitoneal chemotherapy, high-dose chemotherapy with haematopoietic support, prolonged administration of the first-line regimen, second-line single-agent chemotherapy, and biological agents. Clinical studies have given conflicting, inconclusive, and generally disappointing results. A recent US randomised trial appeared to show that the prolonged administration of single-agent paclitaxel (175 mg/m2 every 3 weeks) significantly improved the progression-free survival of complete responders to paclitaxel/platinum-based chemotherapy. Alternative less toxic, and probably more effective schedules of administration of chemotherapy (i.e. weekly paclitaxel) might assure a better balance between quality of life and anti-tumor activity in patients previously exposed to chemotherapy.

Intraperitoneal chemotherapy in ovarian cancer: who and when?

PURPOSE OF REVIEW

Intraperitoneal chemotherapy in ovarian cancer has been studied for several years and developed in many countries. However, despite positive results from well-conducted clinical trials, its clinical application is still controversial. A review of recent advances is presented.

RECENT FINDINGS

Intraperitoneal chemotherapy has been studied in two situations: in the first line, combined with intravenous chemotherapy, or as a consolidation treatment, after surgery and systemic chemotherapy. In the first line, two randomized studies showed an increased survival in patients with intraperitoneal chemotherapy. In patients with pathological complete remission, the theoretical principle remains valid, treating minimal disease, but definitive results from randomized studies are lacking.

SUMMARY

Intraperitoneal chemotherapy is a regional treatment for ovarian cancer. Its development is limited by the reluctance of the medical oncologist community to include this technique in the whole strategy of treatment, despite positive results. However, intraperitoneal chemotherapy should be considered in patients optimally debulked and with minimal residual disease.