title: Single-agent trastuzumab versus trastuzumab plus cytotoxic chemotherapy in metastatic breast cancer: a single-institution experience.
abstract: Trastuzumab has shown significant single-agent activity in patients with Her-2/neu overexpressing metastatic breast cancer, and increased response rates, progression-free and overall survival when added to standard chemotherapy. Despite higher response rates, the combination with chemotherapy has higher toxicity and it remains unknown whether single-agent trastuzumab is equally effective as the combined treatment in terms of progression-free and overall survival. We therefore carried out a retrospective multivariate analysis of 117 patients with Her-2/neu overexpressing metastatic breast cancer who were treated with trastuzumab with or without chemotherapy at a single institution between November 1999 and December 2003. Response rates tended to be higher in patients receiving trastuzumab in combination with chemotherapy (34 versus 8%, p=0.060). However, this did not translate into a benefit in progression-free survival: median (95% confidence interval) progression-free survival was 6.2 (4.45-7.95) months in patients receiving trastuzumab plus chemotherapy versus 4.2 (1.77-6.63) months in those receiving single-agent trastuzumab (p=0.560). Likewise, no significant difference in overall survival was observed: 27.0 (19.9-34.0) versus 23.1 (16.2-30.0) months (p=0.809). We conclude that in the absence of extensive visceral involvement necessitating a higher response rate, single-agent trastuzumab may be a safe and less-toxic alternative to its combined use with other chemotherapy agents. This needs to be confirmed in prospective randomized trials.
authors.affiliation: Clinical Division of Oncology, Department of Medicine I, University Hospital of Vienna, Vienna, Austria. wolfgang.koestler@meduniwien.ac.at
authors.forename: Wolfgang J
authors.initials: WJ
authors.lastname: Köstler
authors.forename: Günther G
authors.initials: GG
authors.lastname: Steger
authors.forename: Michael
authors.initials: M
authors.lastname: Krainer
authors.forename: Gabriela V
authors.initials: GV
authors.lastname: Kornek
authors.forename: Gottfried J
authors.initials: GJ
authors.lastname: Locker
authors.forename: Thomas
authors.initials: T
authors.lastname: Brodowicz
authors.forename: Christine
authors.initials: C
authors.lastname: Marosi
authors.forename: Christian F
authors.initials: CF
authors.lastname: Singer
authors.forename: Gernot
authors.initials: G
authors.lastname: Hudelist
authors.forename: Werner
authors.initials: W
authors.lastname: Rabitsch
authors.forename: Christoph
authors.initials: C
authors.lastname: Wiltschke
authors.forename: Christoph C
authors.initials: CC
authors.lastname: Zielinski
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008875:Middle Aged; D009362:Neoplasm Metastasis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000096:biosynthesis; D012189:Retrospective Studies; D000068878:Trastuzumab
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab