Efficacy and Safety of Trastuzumab as a Single Agent in First-Line Treatment of HER2-Overexpressing Metastatic Breast Cancer.

PURPOSE: To evaluate the efficacy and safety of first-line, single-agent trastuzumab in women with HER2-overexpressing metastatic breast cancer. PATIENTS AND METHODS: One hundred fourteen women with HER2-overexpressing metastatic breast cancer were randomized to receive first-line treatment with trastuzumab 4 mg/kg loading dose, followed by 2 mg/kg weekly, or a higher 8 mg/kg loading dose, followed by 4 mg/kg weekly. RESULTS: The objective response rate was 26% (95% confidence interval [CI], 18.2% to 34.4%), with seven complete and 23 partial responses. Response rates in 111 assessable patients with 3+ and 2+ HER2 overexpression by immunohistochemistry (IHC) were 35% (95% CI, 24.4% to 44.7%) and none (95% CI, 0% to 15.5%), respectively. The clinical benefit rates in assessable patients with 3+ and 2+ HER2 overexpression were 48% and 7%, respectively. The response rates in 108 assessable patients with and without HER2 gene amplification by fluorescence in situ hybridization (FISH) analysis were 34% (95% CI, 23.9% to 45.7%) and 7% (95% CI, 0.8% to 22.8%), respectively. Seventeen (57%) of 30 patients with an objective response and 22 (51%) of 43 patients with clinical benefit had not experienced disease progression at follow-up at 12 months or later. The most common treatment-related adverse events were chills (25% of patients), asthenia (23%), fever (22%), pain (18%), and nausea (14%). Cardiac dysfunction occurred in two patients (2%); both had histories of cardiac disease and did not require additional intervention after discontinuation of trastuzumab. There was no clear evidence of a dose-response relationship for response, survival, or adverse events. CONCLUSION: Single-agent trastuzumab is active and well tolerated as first-line treatment of women with metastatic breast cancer with HER2 3+ overexpression by IHC or gene amplification by FISH.

Effects on quality of life of combined trastuzumab and chemotherapy in women with metastatic breast cancer.

PURPOSE: The study was designed to compare the effects of treatment with a combination of trastuzumab (Herceptin; Genentech, Inc, South San Francisco, CA) and chemotherapy versus chemotherapy alone on health-related quality of life (HRQL) in patients with HER-2/neu overexpressing, metastatic breast cancer. PATIENTS AND METHODS: A sample of 400 patients, not previously treated for metastatic disease and randomized to receive either trastuzumab plus chemotherapy (208 patients) or chemotherapy alone (192 patients), completed the European Organization for Research and Treatment Care Quality of Life Questionnaire at baseline and on at least one subsequent occasion at 8, 20, 32, 44, and 56 weeks. HRQL improvement or worsening was defined as a >or= 10-point change (range, 0 to 100 points) in the scores of six preselected domains (global quality of life [QOL], physical, role, social, and emotional functioning, and fatigue). Stable HRQL was defined as a change of less than 10. A Bonferroni correction was applied for multiple testing. RESULTS: After completion of chemotherapy, patients treated with trastuzumab and chemotherapy reported significant improvement in fatigue (P <.05) as compared with their baseline scores. Higher proportions of patients receiving the combined therapy achieved improvement in global QOL (P <.05) than did patients treated with chemotherapy alone. Higher proportions of the combined therapy group also achieved improvement in physical and role functioning and in fatigue as compared with the chemotherapy group, but the differences were not statistically significant. There were no differences in the proportions of patients in the two groups that reported worsening. CONCLUSION: Statistically significantly higher proportions of patients treated with a combination of trastuzumab and chemotherapy reported improved global QOL than did patients treated by chemotherapy alone.

Efficacy and safety of trastuzumab as a single agent in first-line treatment of HER2-overexpressing metastatic breast cancer.

PURPOSE: To evaluate the efficacy and safety of first-line, single-agent trastuzumab in women with HER2-overexpressing metastatic breast cancer. PATIENTS AND METHODS: One hundred fourteen women with HER2-overexpressing metastatic breast cancer were randomized to receive first-line treatment with trastuzumab 4 mg/kg loading dose, followed by 2 mg/kg weekly, or a higher 8 mg/kg loading dose, followed by 4 mg/kg weekly. RESULTS: The objective response rate was 26% (95% confidence interval [CI], 18.2% to 34.4%), with seven complete and 23 partial responses. Response rates in 111 assessable patients with 3+ and 2+ HER2 overexpression by immunohistochemistry (IHC) were 35% (95% CI, 24.4% to 44.7%) and none (95% CI, 0% to 15.5%), respectively. The clinical benefit rates in assessable patients with 3+ and 2+ HER2 overexpression were 48% and 7%, respectively. The response rates in 108 assessable patients with and without HER2 gene amplification by fluorescence in situ hybridization (FISH) analysis were 34% (95% CI, 23.9% to 45.7%) and 7% (95% CI, 0.8% to 22.8%), respectively. Seventeen (57%) of 30 patients with an objective response and 22 (51%) of 43 patients with clinical benefit had not experienced disease progression at follow-up at 12 months or later. The most common treatment-related adverse events were chills (25% of patients), asthenia (23%), fever (22%), pain (18%), and nausea (14%). Cardiac dysfunction occurred in two patients (2%); both had histories of cardiac disease and did not require additional intervention after discontinuation of trastuzumab. There was no clear evidence of a dose-response relationship for response, survival, or adverse events. CONCLUSION: Single-agent trastuzumab is active and well tolerated as first-line treatment of women with metastatic breast cancer with HER2 3+ overexpression by IHC or gene amplification by FISH.