A pilot study of CHAC-1

Carboplatin/etoposide as first-line chemotherapy in advanced ovarian carcinoma: a pilot study

In a pilot study, 18 patients with advanced ovarian cancer were evaluated for tolerance and response to a combination treatment with a fixed dose of carboplatin (350 mg/m2 given i.v. on day 1) and escalated doses of etoposide (70-130 mg/m2 daily given i.v. on days 1-3) as first-line chemotherapy. The maximum tolerated dose of etoposide was 130 mg/m2 when given i.v. on days 1-3 in combination with 350 mg/m2 carboplatin given i.v. every 4 weeks. At these dose levels, bone marrow toxicity was manageable and did not appear to be cumulative. In all, 12 objective responses, including 9 complete responses (CRs) and 3 partial responses (PRs), were achieved in 18 patients; 6 of the 9 CRs were confirmed as pathological CRs by second-look surgery.

Penetration of carboplatin and cisplatin into rat peritoneal tumor nodules after intraperitoneal chemotherapy

Platinum distribution was studied in rat peritoneal tumors after i.p. treatment with equimolar doses of carboplatin and cisplatin. Low platinum concentrations (4 ppm) were detected in the periphery of the tumor after carboplatin treatment, whereas no platinum was detected 0.5 mm in from the periphery. In contrast, after cisplatin treatment, high platinum concentrations (29 ppm) were measured in the periphery of the tumor and moderate concentrations (14 ppm) were measured in the center. Only following increased carboplatin doses were low platinum concentrations detectable in the tumor. The total platinum concentration in the tumors was determined after equimolar administration of both drugs. In all, 7 times more platinum was detected after cisplatin treatment than after carboplatin treatment, and 10 times more carboplatin than cisplatin had to be injected to obtain comparable platinum concentrations in the tumors. When single cells were incubated with equimolar concentrations of carboplatin and cisplatin, 6-7 times more platinum was found in cells treated with cisplatin. However, pharmacokinetic studies favored i.p. administration of carboplatin because the clearance of this compound from the peritoneal cavity, expressed as t1/2 beta, was lower than that of cisplatin (239 vs 78 min), resulting in an AUC in the peritoneal cavity for both total and ultrafiltered drug that was almost 3 times higher for carboplatin than cisplatin. The AUC for ultrafiltered carboplatin in plasma was 2-fold that for cisplatin (2,801 +/- 210 vs 1,334 +/- 431 microM m). The present study demonstrated that in spite of the pharmacological advantages of carboplatin, its capacity to penetrate into peritoneal tumors and tumor cells is far lower than that of cisplatin.

Carboplatin. A preliminary review of its pharmacodynamic and pharmacokinetic properties and therapeutic efficacy in the treatment of cancer

Carboplatin is a 'second-generation' platinum compound advocated for use in the treatment of patients with ovarian cancer and it has also shown promise in small cell lung cancer, squamous cell carcinomas of the head and neck, and seminomas. Overall, it would appear to have a similar qualitative spectrum of activity to cisplatin. There have been few comparative trials with carboplatin, either alone or in combination with other chemotherapeutic agents, but the limited data suggest comparable efficacy with cisplatin in ovarian cancer. Importantly, the toxicity profile of carboplatin is markedly different from that of cisplatin, with nephrotoxicity, neurotoxicity and ototoxicity occurring only infrequently with carboplatin. As with cisplatin, nausea and vomiting occur in many patients after carboplatin administration, but symptoms are usually delayed for several hours and are mild to moderate in severity - dose-limiting nausea and vomiting are infrequent with carboplatin. The dose-limiting toxicity of carboplatin is myelosuppression, with severe thrombocytopenia and less often leucopenia, which may be more severe in older patients or in those with renal impairment or those who have had previous chemotherapy. Thus, preliminary data suggest that carboplatin is a therapeutically equivalent alternative to cisplatin, but with a differing toxicity profile that should offer advantages over cisplatin in many patients.

Ovarian cancer: the prognostic value of the serum half-life of CA125 during induction chemotherapy

Eighty-five patients with epithelial ovarian cancer were studied to assess the prognostic value of the prechemotherapy serum concentration of CA125 and its half-life during induction therapy. The endpoints of the analysis were progression rate and time to progression. The prechemotherapy CA125 level had no prognostic value (P = 0.36) if the patients were stratified for tumor size. The half-life of CA125, however, was an independent prognostic variable (P = 0.01). Patients with a half-life of 20 days and more had a 3.2 times higher progression rate and a significantly shorter median time to progression of only 11 months, as compared to 43 months for patients with a half-life of less than 20 days.

Carboplatin in combination therapy for ovarian cancer

Cisplatin today is a cornerstone of combination chemotherapy for ovarian cancer. Carboplatin seems equal to cisplatin in antitumour activity, but has a different toxicity profile. After a feasibility study, a randomized phase III study in ovarian cancer stage II, III, and IV was undertaken, comparing carboplatin with cisplatin in combination with cyclophosphamide, doxorubicin and hexamethylmelamine. Preliminary analysis of this study reveals no statistically significant difference in response rate. Notwithstanding equal haematological toxicity, the other side effects evoked by carboplatin in combination treatment are much milder than those evoked by cisplatin. Further analysis will be necessary to draw definite conclusions about the results obtained.