title: Outcomes of HER2-positive early breast cancer patients in the pre-trastuzumab and trastuzumab eras: a real-world multicenter observational analysis. The RETROHER study.
abstract: Addition of trastuzumab to adjuvant chemotherapy has dramatically reduced the risk of recurrence and has become the standard of care for human epidermal growth factor receptor 2 (HER2)-positive early breast cancer patients. Since most data on trastuzumab benefits come from clinical trials, conducted in selected patient populations, we performed a retrospective analysis of HER2-positive early breast cancer patients treated in the "pre-trastuzumab" and "trastuzumab" eras, with the aim to determine patients' outcomes in real-world practice. 925 consecutive HER2-positive breast cancer patients treated with adjuvant chemotherapy in ten Italian oncologic centers were identified. Patients who had received adjuvant chemotherapy alone (cohort A, 352 patients), and patients who had received adjuvant chemotherapy followed or combined with trastuzumab (cohort B, 573 patients) were analyzed. Relapse rate at 3 years, relapse-free survival, and overall survival were significantly more unfavorable in the cohort A than in the cohort B (p < 0.0001). In multivariate analysis, factors related to relapse were younger age, advanced stage at diagnosis, absence of hormonal and of trastuzumab therapy. The benefit derived from the addition of trastuzumab was independent of nodal status and hormonal receptors expression. A subgroup analysis including 163 "triple positive" tumors with high levels of estrogen and progesterone receptor (TP50) suggested that addition of trastuzumab to adjuvant chemotherapy and hormonal therapy did not translate into better outcomes. In our analysis, trastuzumab benefit was confirmed in all but a small subset of TP50 tumors subgroups. In this subset further investigations are needed.
authors.affiliation: Division of Medical Oncology B, "Regina Elena" National Cancer Institute, Via Elio Chianesi, 53, 00144, Rome, Italy, pvici@ifo.it.
authors.forename: Patrizia
authors.initials: P
authors.lastname: Vici
authors.forename: Laura
authors.initials: L
authors.lastname: Pizzuti
authors.forename: Clara
authors.initials: C
authors.lastname: Natoli
authors.forename: Luca
authors.initials: L
authors.lastname: Moscetti
authors.forename: Lucia
authors.initials: L
authors.lastname: Mentuccia
authors.forename: Angela
authors.initials: A
authors.lastname: Vaccaro
authors.forename: Domenico
authors.initials: D
authors.lastname: Sergi
authors.forename: Luigi
authors.initials: L
authors.lastname: Di Lauro
authors.forename: Patrizia
authors.initials: P
authors.lastname: Trenta
authors.forename: Patrizia
authors.initials: P
authors.lastname: Seminara
authors.forename: Daniele
authors.initials: D
authors.lastname: Santini
authors.forename: Laura
authors.initials: L
authors.lastname: Iezzi
authors.forename: Nicola
authors.initials: N
authors.lastname: Tinari
authors.forename: Ilaria
authors.initials: I
authors.lastname: Bertolini
authors.forename: Valentina
authors.initials: V
authors.lastname: Sini
authors.forename: Marcella
authors.initials: M
authors.lastname: Mottolese
authors.forename: Diana
authors.initials: D
authors.lastname: Giannarelli
authors.forename: Francesco
authors.initials: F
authors.lastname: Giotta
authors.forename: Marcello
authors.initials: M
authors.lastname: Maugeri-Saccà
authors.forename: Maddalena
authors.initials: M
authors.lastname: Barba
authors.forename: Paolo
authors.initials: P
authors.lastname: Marchetti
authors.forename: Andrea
authors.initials: A
authors.lastname: Michelotti
authors.forename: Isabella
authors.initials: I
authors.lastname: Sperduti
authors.forename: Teresa
authors.initials: T
authors.lastname: Gamucci
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008875:Middle Aged; D055815:Young Adult; D061067:Antibodies, Monoclonal, Humanized / Q000008:administration & dosage; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000175:diagnosis / Q000188:drug therapy / Q000378:metabolism / Q000401:mortality / Q000473:pathology; D017024:Chemotherapy, Adjuvant; D055088:Early Detection of Cancer; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D012189:Retrospective Studies; D016019:Survival Analysis; D000068878:Trastuzumab; D016896:Treatment Outcome
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab; C508053:ERBB2 protein, human