EORTC 10941: A phase II study of liarozole in postmenopausal patients with 'chemotherapy-resistant' or 'potentially hormone sensitive' metastatic breast cancer.

Liarozole is an imidazole compound that inhibits enzymes involved in steroid hormone aromatisation and retinoid metabolism. The IDBBC branch of the EORTC has performed a series of phase II studies of the agent in four groups of postmenopausal women with metastatic breast cancer. This paper reports the results of the first two groups: 'Chemotherapy Resistant' (unrestricted ER status, 1 or 2 prior chemotherapy regimens, 0-2 prior hormonal therapies) and 'Potentially Hormone Sensitive' (ER positive or unknown, 1 or 2 prior hormonal therapies with a substantial disease free interval or progression free survival, and no history of chemotherapy for metastatic disease). Liarozole was administered at 150-300 mg orally bid. The objective response rate was 12% in the 'Chemotherapy Resistant' group (n = 34), and 22% in the 'Potentially Hormone Sensitive' group (n = 37), with median response durations of 9 and 14 months, respectively. Median time to treatment failure was only 2 months in both groups, due largely to the significant percentage (24%) of patients who ceased treatment following excessive mucocutaneous and gastrointestinal toxicity. This adverse event profile will limit its use in breast cancer. Results of the 'ER negative' and 'Tamoxifen Refractory' groups will be reported in a future paper.

Paclitaxel versus doxorubicin as first-line single-agent chemotherapy for metastatic breast cancer: a European Organization for Research and Treatment of Cancer Randomized Study with cross-over.

PURPOSE: To compare the efficacy of paclitaxel versus doxorubicin given as single agents in first-line therapy of advanced breast cancer (primary end point, progression-free survival ¿PFS) and to explore the degree of cross-resistance between the two agents. PATIENTS AND METHODS: Three hundred thirty-one patients were randomized to receive either paclitaxel 200 mg/m(2), 3-hour infusion every 3 weeks, or doxorubicin 75 mg/m(2), intravenous bolus every 3 weeks. Seven courses were planned unless progression or unacceptable toxicity occurred before the seven courses were finished. Patients who progressed within the seven courses underwent early cross-over to the alternative drug, while a delayed cross-over was optional for the remainder of patients at the time of disease progression. RESULTS: Objective response in first-line therapy was significantly better (P =.003) for doxorubicin (response rate ¿RR, 41%) than for paclitaxel (RR, 25%), with doxorubicin achieving a longer median PFS (7.5 months for doxorubicin v 3.9 months for paclitaxel, P <.001). In second-line therapy, cross-over to doxorubicin (91 patients) and to paclitaxel (77 patients) gave response rates of 30% and 16%, respectively. The median survival durations of 18.3 months for doxorubicin and 15.6 months for paclitaxel were not significantly different (P =.38). The doxorubicin arm had greater toxicity, but this was counterbalanced by better symptom control. CONCLUSION: At the dosages and schedules used in the present study, doxorubicin achieves better disease and symptom control than paclitaxel in first-line treatment. Doxorubicin and paclitaxel are not totally cross-resistant, which supports further investigation of these drugs in combination or in sequence, both in advanced disease and in the adjuvant setting.

A study of the value of p53, HER2, and Bcl-2 in the prediction of response to doxorubicin and paclitaxel as single agents in metastatic breast cancer: a companion study to EORTC 10923.

This study assesses the potential value of the tumor markers p53, HER2, and Bcl-2 in predicting the clinical response to doxorubicin and paclitaxel as single agents in the treatment of metastatic breast cancer. The primary tumors of 114 patients in the European Organization for Research and Treatment of Cancer 10923 trial were assessed by immunohistochemistry using monoclonal antibodies; the results were correlated with clinical response to therapy. HER2 was positive in 24% of patients, p53 was positive in 25% of patients, and Bcl-2 was positive in 49% of patients. There was no correlation between the expression of any of the markers and the clinical response to either agent. Although methodologically limited, this study does not support the use of p53, HER2, or Bcl-2 to assist the selection of anthracycline versus taxane in metastatic breast cancer.

Vorozole (Rivizor): an active and well tolerated new aromatase inhibitor for the treatment of advanced breast cancer patients with prior tamoxifen exposure. Investigational Drug Branch of the European Organization for Research and Treatment of Cancer (EORTC) Breast Cancer Cooperative Group.

Vorozole (Rivizor) is a potent and stereospecific inhibitor of aromatase having shown promising endocrine effects in phase I studies. In the present trial, 27 postmenopausal patients with advanced breast cancer, measurable lesions, presumably hormone responsive (ER or PR+, or ER? with disease-free survival longer than 1 year, or prior documented response to tamoxifen), were treated with vorozole one tablet 2.5 mg daily. All had been previously treated with tamoxifen as adjuvant (two patients) or for advanced disease (24 patients), or both (one patient). Objective remissions were observed in eight patients (30%) with two complete responses (CR) and six partial responses (PR) lasting for a median of 14.3 months (range 6.8-40.6); nine stabilizations were also recorded (median 7.9 months; range 3.7-40.1). Median time to progression for the 27 patients was 5.9 months. Sites of response were skin (three patients), lymph nodes (two patients), lung (two patients) and chest wall plus lymph nodes (one patient). Treatment was very well tolerated: mild hot flushes (four patients), gastrointestinal complaints (four patients) and no significant toxicity (common toxicity criteria grade above 2) or drug-related severe adverse event. It is concluded that vorozole is an active second-line endocrine treatment, deserving consideration for randomized comparison with other agents such as aminoglutethimide, megestrol acetate or medroxyprogesterone acetate.

Mitomycin C and vinblastine in combination with amifostine in metastatic breast cancer. A feasibility study of the EORTC--Investigational Drug Branch for Breast Cancer (IDBBC).

Mitomycin C (MMC)-vinblastine (VBL) is a regimen that has commonly been used as salvage therapy for advanced breast cancer for many years. The hematologic toxicity of this combination is one aspect that limits its usefulness. Amifostine, an organic thiophosphate, has been developed as a selective chemoprotective agent. In this pilot study, we tested the feasibility of MMC/VBL administration in combination with amifostine and we monitored the hematologic toxicity closely. Patients having failed one or two chemotherapy regimens for advanced breast cancer, with a good performance status scored at 2 or better and measurable or evaluable lesion(s), were eligible. They were treated according to the following schedule: mitomycin C 10 mg/m2 i.v. day 1, vinblastine 5 mg/m2 i.v. day 1 and 15, amifostine 910 mg/m2 in short i.v. infusion prior to MMC. Premedication consisted of dexamethasone 3 x 20 mg, haloperidol 2 x 0.5 mg p.o., hydration with 11 of normal saline, metoclopramide 1.5 mg/kg in short infusion and procyclide HCl 10 mg i.v. Cycles were repeated every 4 weeks. In all, 14 cycles were administrated to six heavily pretreated patients. Following the first cycle, five of the six patients experienced grade 3 or 4 neutropenia on day 15, and consequently did not receive the second vinblastine administration as planned. Three out of four patients receiving two or more cycles had moderate thrombocytopenia. There were no patients with neutropenic fever or major bleeding problems. The MMC/VBL+amifostine regimen was well tolerated regarding other toxicities. Neither amifostine-related acute vomiting nor any significant decrease in blood pressure was observed. Administration of amifostine in combination with MMC/VBL was feasible but in this group of heavily pretreated patients there were no hints of a protective effect of amifostine on the hematologic toxicity profile of this chemotherapy regimen.

Corticosteroids significantly delay the onset of docetaxel-induced fluid retention: final results of a randomized study of the European Organization for Research and Treatment of Cancer Investigational Drug Branch for Breast Cancer.

PURPOSE: To confirm the efficacy of docetaxel in patients with breast cancer previously treated with one chemotherapy regimen for advanced or metastatic disease and to compare the incidence of fluid retention (FR) and skin toxicity when docetaxel is administered with and without prophylactic corticosteroids. PATIENTS AND METHODS: Eighty-three patients, pretreated with one chemotherapy regimen for metastatic breast cancer (MBC) with bidimensionally measurable and progressive disease, were eligible for this randomized trial. Docetaxel with prophylactic oral antihistamine was administered at a dose of 50 mg/m2 as a 1-hour infusion on days 1 and 8 every 21 days and patients were randomized to receive methylprednisolone (40 mg days -1, 0, 1, 7, 8, and 9 of each cycle) (arm A) or no methylprednisolone (arm B). RESULTS: Twenty-eight patients (34%, 95% confidence interval [CI], 23% to 45%) achieved on objective response. The median time to disease progression and median overall survival time were 5 and 13.5 months, respectively. In total, 415 cycles of docetaxel were administered (arm A: N = 219, median = six; arm B: N = 196, median = five). The most common toxicity observed was grade 3 or 4 neutropenia, which occurred in 79% of patients. Clinically significant nonhematologic side effects included skin reactions and asthenia. In an intent-to-treat analysis, patients who received methylprednisolone premedication had a delayed onset of FR (median time to onset of FR: arm A, 84 days; arm B, 62 days; P = .01) and received a higher median cumulative dose of docetaxel before the onset of FR (arm A, 333 mg/m2; arm B, 215 mg/m2; P = .001). There was no statistically significant difference in the incidence of skin toxicity between the two arms. CONCLUSION: Docetaxel, at this dose and schedule, has definite antitumor activity in pretreated MBC patients. Moreover, this is the first randomized trial to show that corticosteroids have a favorable impact on docetaxel-induced FR.

An ongoing European organization for research and treatment of cancer crossover trial comparing single-agent paclitaxel and doxorubicin as first- and second-line treatment of advanced breast cancer.

The activity of paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) in advanced breast cancer patients who have failed doxorubicin treatment is well established, but the optimal sequence between these two important agents remains to be determined. The European Organization for Research and Treatment of Cancer therefore designed a prospective randomized clinical trial in which patients not exposed to anthracyclines in the adjuvant setting received either first-line paclitaxel, given as a 3-hour infusion at a dose of 200 mg/m2 followed at the time of disease progression by second-line doxorubicin, given as a bolus injection at a dose of 75 mg/m2 or the reverse sequence. The target accrual is 330 patients. Interim results on 207 evaluable patients of 289 randomized are presented.