Outcome of patients with HER2-positive advanced breast cancer progressing during trastuzumab-based therapy.

We sought to describe patterns of treatment and clinical outcome in patients with HER2-positive advanced breast cancer progressing on trastuzumab-based therapy. One hundred eighty-four consecutive HER2-positive advanced breast cancer patients received trastuzumab-based therapy between September 1999 and September 2004. Patients were followed up until death or May 2005. For patients progressing on trastuzumab-based therapy, we calculated the response rate (RR) to the first post-progression treatment, overall survival (OS) from the first administration of trastuzumab, time to second progression (TT-SP), and post-progression survival (PPS), according to treatment. At the time of this analysis, 132 patients had progressed on trastuzumab-based therapy, and 89 had died. Of the progressing patients, 21 experienced rapid progression and could not receive additional anticancer treatments;40 patients continued trastuzumab either alone (12 patients with isolated central nervous system progression), with chemotherapy (23 patients), or with endocrine therapy (5 patients); and 71 stopped trastuzumab and received chemotherapy (61 patients) or endocrine therapy (10 patients) as the first post-progression treatment. Excluding patients with rapid progression, clinical outcomes were similar whether trastuzumab was continued or not, in terms of RR (18% and 27%, respectively), OS (31 and 30 months, respectively), TT-SP (6 and 7 months, respectively), and PPS (21 and 19 months, respectively). The clinical outcome of patients with HER2-positive advanced breast cancer progressing during trastuzumab-based therapy might not be influenced by continuing trastuzumab. The optimal therapeutic strategy in this setting of patients needs evaluation in randomized trials.

A phase II study of three-weekly docetaxel and weekly trastuzumab in HER2-overexpressing advanced breast cancer.

BACKGROUND: To test safety and activity of 3-weekly doses of docetaxel and a weekly dose of trastuzumab in women with HER2-overexpressing advanced breast cancer. PATIENTS AND METHODS: Forty-two women, median age 53 years (range 36-73 years), with HER2-overexpressing advanced breast cancer were enrolled in a study of docetaxel, 75 mg/m(2) q3w for 6 cycles, and trastuzumab, 4 mg/kg loading dose, 2 mg/kg weekly thereafter. Thirty-four patients (81%) had visceral metastatic involvement. Thirty-five patients had received prior chemotherapy as part of their treatment: adjuvant/neoadjuvant (26), metastatic (2) and both (7). Thirty-one patients had been previously exposed to an anthracycline and 11 to paclitaxel. Four patients had previously received high-dose chemotherapy followed by autologous stem cell transplant. RESULTS: 226 cycles (median 6, range 1-6) were administered. The median delivered dose intensity for docetaxel was 24 mg/m(2)/week (range 16-25 mg/m(2)/week). The intent to treat overall response rate was 67% (95% confidence interval, 52-79%). Median progression-free survival, time to treatment failure, and duration of response were 9, 8 and 12 months, respectively. Symptomatic cardiotoxicity (grade 3) occurred in 1 patient. The most common grade 3/4 toxicity was neutropenia (76% of the patients), although febrile neutropenia did not occur. CONCLUSIONS: Three-weekly doses of docetaxel and a weekly dose of trastuzumab is an active and safe combination in patients with HER2-overexpressing advanced breast cancer.

Safety and activity of docetaxel and trastuzumab in HER2 overexpressing metastatic breast cancer: a pilot phase II study.

We conducted a pilot phase II trial of trastuzumab administered concurrently with docetaxel in women with HER2-overexpressing advanced breast cancer. Twenty-five women with HER2-positive (3+ by immunohistochemistry = 16, 2+ = 9) metastatic breast cancer received docetaxel (75 mg/m every 3 weeks for 6 cycles) and trastuzumab (4 mg/kg loading dose, 2 mg/kg weekly thereafter). Twenty-three patients (92%) had visceral metastatic involvement. Twenty-three patients had received prior chemotherapy as part of adjuvant (18), metastatic (2), and both (3) treatment. The number of cycles administered was 121 (median 6, range 1-6). Symptomatic cardiotoxicity (GIII) occurred in one patient. The most common grade GIII/IV toxicity was neutropenia (80% of the cycles), although febrile neutropenia did not occur. No other GIII/IV toxicities were observed. Response rate was 70% (1 complete response and 15 partial responses) in 23 evaluable patients. The combination of docetaxel and trastuzumab is well tolerated and has clinically meaningful antitumor activity.