Filgrastim and lack of support of intensive adjuvant chemotherapy for high-risk breast cancer patients.

The capacity of filgrastim to reduce the myelotoxicity of a 16-week intensive chemotherapy regimen has been investigated in 24 operable breast cancer patients with > or = 10 metastatic axillary nodes. Five patients were treated with chemotherapy alone (control group); 19 patients were treated with chemotherapy and filgrastim, 5 microg/kg/day s.c. Six patients in the latter group were treated from day 4 to day 7 (level 1), seven from day 10 to day 13 (level 2), and six from day 4 to day 7 and day 10 to day 13 (level 3). A total of 135 courses were administered: neutropenia was the most severe toxicity, and the prophylactic use of filgrastim does not reduce its severity. Moreover, the dose intensities of antiblastic drugs actually received by the patients were not significantly different in the four study groups. Among the patients treated at level 3, there were three toxic deaths: one patient died because of febrile neutropenia and sepsis, two patients because of ischemic colitis. At a median follow-up of 15 months, 17 patients were alive, and 15 patients were disease free. The use of filgrastim does not ameliorate myelotoxicity and does not allow the administration of the planned doses of antiblastic drugs of a 16-week intensive chemotherapy regimen.

Paclitaxel combinations as front-line and salvage chemotherapy regimens in advanced breast cancer.

Thirty-two patients with advanced breast cancer have been treated with epirubicin 90 mg/m2, immediately followed by paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) infused over 3 hours, every 21 days. The starting paclitaxel dose was 135 mg/m2, increased in subsequent triplets of patients until the maximum tolerated dose was reached at 200 mg/m2. One hundred seventy-six courses have been administered; dose-related grade 4 neutropenia was observed in 66% of the courses, with 12 episodes of febrile neutropenia. Two patients showed a decline of left ventricular ejection fraction below 50% after six courses, but no signs of congestive heart failure have been reported. The response rate is 76% (95% confidence interval, 56% to 90%), with 14% complete remissions. This level of activity is encouraging considering that 84% of the patients had failed adjuvant chemotherapy (with anthracyclines in 14 cases), and 19 had progressive disease following hormone therapy for metastasis. In another study, the toxicity and activity of a salvage regimen consisting of paclitaxel 135 mg/m2 over 3 hours plus vinorelbine 25 mg/m2 in an intravenous bolus on day 1 were evaluated; vinorelbine was given again on day 8 (in 14 patients) or on day 3 (in 20 patients), and the courses were repeated every 3 weeks. Thirty-four previously treated patients with advanced breast cancer entered the study; 20 had received one prior line of chemotherapy, II had two lines, and three patients had three lines. Thirty-two patients had been exposed to anthracyclines. Grade 4 neutropenia was observed in 64% of the courses, with 13 episodes of febrile neutropenia; four episodes of grade 3 mucositis have been reported with vinorelbine days 1 and 3. A delay in the administration of chemotherapy was necessary in 17% of the courses with vinorelbine days 1 and 8 and 16% of the courses with vinorelbine days 1 and 3; moreover, the vinorelbine dose was reduced or the drug omitted on day 8 in 86% of the courses and on day 3 in 16% of the course. An objective response was achieved in 43% of the patients. In conclusion, the combination of paclitaxel plus vinorelbine is an active salvage regimen and can be administered at greater dose intensity with the day 1 and 3 schedule.

A dose-finding study of epirubicin in combination with paclitaxel in the treatment of advanced breast cancer.

We performed a dose escalation study to evaluate the maximum tolerated dose of paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) given over 3 hours plus bolus epirubicin 90 mg/m2. The starting dose of paclitaxel, 135 mg/m2, was escalated by 20-mg/m2 increments in cohorts of three to six patients. Courses were repeated every 3 weeks. Filgrastim (5 micrograms/kg/d) was administered to shorten the duration of grade 4 neutropenia lasting longer than 72 hours. Twenty-nine patients have been treated, 86% of whom had failed adjuvant chemotherapy (with anthracyclines in 14 cases). One hundred forty-eight courses have been administered, and the paclitaxel dose has been escalated to 225 mg/m2 without reaching the maximum tolerated dose. The most frequent dose-related toxicity has been grade 4 neutropenia, which occurred in 59% of courses. The median duration of grade 4 neutropenia was 4 days, which was shortened with filgrastim only in patients treated with paclitaxel 225 mg/m2. Eleven episodes of febrile neutropenia (7% of courses) have been observed. Nonhematologic toxicities were mild or moderate: grade 1 or 2 peripheral neuropathy was reported by 41% and 10% of patients, respectively. The cardiac toxicities of this regimen were surprisingly low: median left ventricular ejection fraction was 57% at study entry and 56% after six courses. Only two patients showed a decrease of left ventricular ejection fraction below 50% after six courses, and no signs of anthracycline-induced congestive heart failure were noted. The activity of this novel combination is encouraging: the overall response rate is 80%, with 16% complete responses. We have demonstrated that the combination of epirubicin plus paclitaxel given over 3 hours is feasible with acceptable toxicities, does not appear to be associated with clinically relevant cardiotoxicity, and is active in a population of patients who have failed adjuvant chemotherapy.

Paclitaxel in combination with vinorelbine in pretreated advanced breast cancer patients.

This phase II study combined paclitaxel (Taxol; Bristol Myers Squibb Company, Princeton, NJ) 135 mg/m2 by 3-hour infusion on day 1 and vinorelbine 25 mg/m2 on days 1 and 8 (in the first 14 patients) or on days 1 and 3 (in the subsequent 20 patients). The courses were repeated every 3 weeks. The second vinorelbine dose (on days 3 or 8) was reduced or omitted according to the toxicities encountered. Thirty-four patients have been treated to date; 21 had received one prior regimen of chemotherapy, 11 had two prior regimens, and two had three prior regimens. Only two patients (6%) had not been exposed to anthracyclines. One hundred twenty-six courses have been administered: 52 with vinorelbine given on days 1 and 8, and 74 with vinorelbine administered on days 1 and 3. The most frequent toxicity was grade 4 neutropenia, which occurred in 64% of the courses; 13 episodes of febrile neutropenia have been reported in eight patients. Filgrastim was administered in 43% of the courses because of febrile neutropenia or delayed recovery (> 72 hours) from grade 4 neutropenia. Mucositis was observed in 18% of the courses (12% grade 1, 3% grade 2, and 3% grade 3). The dose of vinorelbine was reduced or omitted in 86% of courses with the days 1 and 8 schedule, and in 48% of courses with the days 1 and 3 schedule. Among 28 evaluable patients, two complete and 10 partial responses have been observed (response rate, 43%, 95% confidence interval, 19% to 51%). Median duration of response is 5+ months (range, 1 to 15 months). In conclusion, this combination is active and has acceptable toxicities in anthracycline-pretreated breast cancer patients. The delivered dose intensity of vinorelbine is higher with the schedule adopted later in the study, with vinorelbine given on days 1 and 3.