Long-term follow-up confirms a survival advantage of the paclitaxel-cisplatin regimen over the cyclophosphamide-cisplatin combination in advanced ovarian cancer

Two independent and consecutive randomized clinical trials, conducted by the American Gynecological Oncology Group and by an European-Canadian Intergroup, have shown superiority, in clinical response rate, progression-free survival, and overall survival, of a cisplatin-paclitaxel regimen over cisplatin-cyclophosphamide given as first-line chemotherapy for women with advanced epithelial ovarian cancer. The results of these studies, published with a median follow-up of about 3 years, have been updated with a 6.5-year follow-up: In each case, an 11% absolute gain in survival favoring the paclitaxel arm is shown; this advantage remains both statistically and clinically significant and supports a role for paclitaxel in frontline chemotherapy for advanced ovarian cancer.

Long-term follow-up confirms a survival advantage of the paclitaxel–cisplatin regimen over the cyclophosphamide–cisplatin combination in advanced ovarian cancer

Two independent and consecutive randomized clinical trials, conducted by the American Gynecological Oncology Group and by an European–Canadian Intergroup, have shown superiority, in clinical response rate, progression-free survival, and overall survival, of a cisplatin–paclitaxel regimen over cisplatin–cyclophosphamide given as first-line chemotherapy for women with advanced epithelial ovarian cancer. The results of these studies, published with a median follow-up of about 3 years, have been updated with a 6.5-year follow-up: In each case, an 11% absolute gain in survival favoring the paclitaxel arm is shown; this advantage remains both statistically and clinically significant and supports a role for paclitaxel in frontline chemotherapy for advanced ovarian cancer.

Phase II study of CGP 69846A (ISIS 5132) in recurrent epithelial ovarian cancer: an NCIC clinical trials group study (NCIC IND.116)

OBJECTIVE

ISIS 5132 is a 20-base phosphorothioate DNA oligonucleotide against human c-raf kinase, a downstream effector of ras oncogene function. C-raf kinase is a molecule in the MAP kinase signaling cascade which is essential for cellular proliferation, the overexpression of which leads to malignant expression. Activity of this compound was documented in a woman with ovarian cancer in a Phase I study.

METHODS

We evaluated ISIS 5132 at a dose of 4 mg/kg/day by continuous venous infusion, administered for 21 days q 4 weeks in 22 patients with recurrent ovarian cancer in a standard two-stage Phase II design. Three patients were ineligible; 19 patients are evaluable for toxicity and 16 for response. All patients had previously received systemic therapy for ovarian cancer (6 had one and 13 had two prior regimens). Patients were treated with a median of two cycles and 79% of the patients received >90% planned dose intensity.

RESULTS

ISIS 5132 was well tolerated with no episodes of Grade 3 or 4 hematologic or biochemical (creatinine, AST, bilirubin) toxicity. There were six episodes of grade 3 nonhematologic toxicity in 4 patients thought to be treatment related (lethargy 2; anorexia 1; abdominal pain 2; shortness of breath 1). No responses were seen in the 16 patients who are evaluable for response; 4 had stable disease for a median of 3.8 months and 12 patients had documented progressive disease.

CONCLUSION

ISIS 5132 at 4 mg/kg/day as a single agent did not show activity in recurrent ovarian cancer.

Intergroup collaboration in ovarian cancer: a giant step forward

The rather slow evolution of so-called "optimal chemotherapy" for ovarian cancer is the result of suboptimal randomised clinical trials, not having the statistical power to identify truly superior regimens, and of the lack of systematic comparisons of new agents with relevant control arms. There is little doubt that we need international collaboration to move the field forward in a timely and coherent manner. European and transatlantic collaboration represents the beginning of the process and point to the success that can await us if the drive to work together remains strong. A similar organisation as for breast cancer (Breast International Group, BIG) needs to be established for ovarian cancer.

A phase I study of bi-weekly paclitaxel/cisplatin as initial therapy for advanced ovarian cancer. A study of the National Cancer Institute of Canada Clinical Trials Group

PURPOSE

Given the potential for improved outcomes, a phase I trial was initiated to develop a paclitaxel/cisplatin regimen that could be delivered every two weeks to women with newly diagnosed advanced ovarian cancer.

PATIENTS AND METHODS

From 1992 to 1994, 29 (28 eligible) patients were enrolled in a dose-seeking trial. All received 60 mg/m2 of cisplatin preceded by paclitaxel infused over three hours. The paclitaxel dose was excalated from an initial level of 90 mg/m2 by 10 mg/m2 increments in successive cohorts of patients.

RESULTS

At 120 mg/m2 of paclitaxel, the dose-limiting toxicity was granulocytopenia which prevented retreatment on time. The recommended dose level was therefore paclitaxel 110 mg/m2 infused over three hours with cisplatin 60 mg/m2, repeated bi-weekly for eight cycles.

CONCLUSION

This bi-weekly schedule of paclitaxel/cisplatin provides no advantage in terms of dose-intensity nor total dose of paclitaxel in comparison to more common regimens given tri-weekly.

Preliminary evaluation of a multicenter, randomized comparative study of TAXOL (paclitaxel) dose and infusion length in platinum-treated ovarian cancer. Canadian-European Taxol Cooperative Trial Group

TAXOL (paclitaxel), a new cytotoxic agent of the taxane class, has demonstrated activity against ovarian cancer. To address questions of a dose-response effect and the value of premedication to prevent hypersensitivity reactions during brief TAXOL infusions, a trial with a 2 x 2 factorial design was begun in patients with relapsed ovarian cancer. From July 1991 through March 1992, 407 patients who had failed one or two prior platinum regimens and who had measurable or evaluable disease were randomized to either 175 or 135 mg/m2 TAXOL administered by either 24- or 3-h infusion. Premedication to prevent hypersensitivity reactions, consisting of steroids, antihistamines, and H2-blockers, was administered to all patients before TAXOL. Toxicity and response data on 298 and 286 patients, respectively, are presented. Overall response rate was 18.5% (53 of 286 patients, 95% confidence interval 13.9% to 23.2%). The results suggest that TAXOL can be given safely over 3 h with premedication. Neutropenia appears to be related more to schedule than to dose, although neuropathy is primarily dose-related. Responses occurred more frequently in those who received 175 mg/m2, but analysis of all accrued patients is necessary before a final conclusion can be drawn. Studies administering TAXOL over 3 h at maximally tolerated doses are warranted.

Cisplatin-cyclophosphamide versus carboplatin-cyclophosphamide in advanced ovarian cancer: a randomized phase III study of the National Cancer Institute of Canada Clinical Trials Group

PURPOSE

Given the potential for improved tolerance, a trial was initiated to compare the toxicity and efficacy of a standard regimen of cisplatin-cyclophosphamide (75 mg/m2 and 600 mg/m2, respectively) with an experimental regimen of carboplatin-cyclophosphamide (300 mg/m2 and 600 mg/m2, respectively) in women with postoperative macroscopic residual ovarian cancer.

PATIENTS AND METHODS

Between 1985 and 1989, 447 (417 eligible) patients were randomized. Treatment arms were well balanced; most patients had stage III (82%), grade 3 (54%) tumors with bulky residual (greater than 2 cm in 59%), and good performance status (Eastern Cooperative Oncology Group [ECOG] 0 or 1, 77%). Response was assessed after six 4-week cycles.

RESULTS

The treatments were equally deliverable, with 76% of patients completing their allocated regimen. The reported reasons for failure to complete treatment differed; toxicity/refusal predominated on the cisplatin arm, and progressive disease predominated on the carboplatin arm (P = .0092). Cisplatin-treated patients were more likely to develop neuropathy and nephropathy, and carboplatin patients experienced myelosuppression, particularly thrombocytopenia. Efficacy was similar, with no significant differences for the cisplatin and carboplatin arms in clinical response rate (57% v 59% in those with measurable disease), pathologic response rate (52% v 54% in those suitable for relaparotomy), time to progression (median, 56 v 58 weeks), or overall survival (median, 100 weeks v 110 weeks). Time to progression and survival were predicted by residual disease size, performance status, and treatment center (with those treated at centers that accrued more patients doing better).

CONCLUSION

Neither regimen is optimal in that relapse remains the norm. It may be inappropriate to expect that any single regimen can be an effective therapy for all patients with advanced ovarian cancer. Both cisplatin and carboplatin are likely to have a role in future treatment strategies.

Chronic hypomagnesemia caused by cisplatin: effect of calcitriol

A group of six patients with hypomagnesemia (serum magnesium less than or equal to 0.5 mmol/L), previously given treatment with cisplatin for ovarian or testicular cancer, received calcitriol at a dose of 0.5 to 1.0 microgram/day for a period of 4 weeks to determine whether treatment with this vitamin D metabolite could improve their hypomagnesemia. In response to treatment, the serum magnesium concentration fell progressively in association with a rise in serum and urinary calcium levels and a decrease in parathyroid hormone level. In a single previous report, active vitamin D metabolites markedly improved renal magnesium wasting. However, in the present study, increases in serum and urinary calcium levels and suppression of parathyroid hormone, factors known to decrease magnesium reabsorption, presumably overwhelmed any direct effect calcitriol may have had to enhance magnesium reabsorption, so that the net effect was a marked exacerbation of the renal magnesium wasting.

Toxicity of abdominopelvic radiation in advanced ovarian carcinoma patients after cisplatin/cyclophosphamide therapy and second-look laparotomy

Twenty-seven advanced ovarian carcinoma patients who had received six courses of cyclophosphamide/cisplatin and had either microscopic disease (15 patients) or no pathologically detectable disease (12 patients) after second-look laparotomy were treated with abdominopelvic radiation (2250 cGy to the abdomen and pelvis and a 2250-cGy pelvic boost). Acute myelosuppression or gastrointestinal toxicity prevented completion of treatment in only three patients. However, bowel obstruction occurred in 13 (48%), ten of whom required surgery. Five of these ten had recurrent tumor, but the other five did not. Subsequently two of the latter five did develop a recurrence, one in the lung and one in the liver. A third patient died as an indirect result of radiation damage to the bowel. Median follow-up duration is 17 months from completion of radiation. So far, 13 (48%) have developed progressive disease: four (33%) of the 12 who had a negative second-look laparotomy and nine (60%) of the 15 who had microscopic disease before radiation. While acute toxicity is tolerable, the incidence of serious chronic bowel toxicity is high. Efforts should be made to alter this therapy in order to decrease the frequency of long-term morbidity.