title: Switching to anastrozole versus continued tamoxifen treatment of early breast cancer: preliminary results of the Italian Tamoxifen Anastrozole Trial.
abstract: OBJECTIVE
  Tamoxifen, which is actually the gold standard adjuvant treatment in estrogen receptor-positive early breast cancer, is associated with an increased risk of endometrial cancer and other life-threatening events. Moreover, many women relapse during or after tamoxifen therapy because of the development of resistance. Therefore new approaches are required.
  
  
  METHODS
  We conducted a prospective randomized trial to test the efficacy of switching postmenopausal patients who were already receiving tamoxifen to the aromatase inhibitor anastrozole. After 2 to 3 years of tamoxifen treatment, patients were randomly assigned either to receive anastrozole 1 mg/d or to continue receiving tamoxifen 20 mg/d, for a total duration of treatment of 5 years. Disease-free survival was the primary end point. Event-free survival, overall survival, and safety were secondary end points.
  
  
  RESULTS
  Four hundred forty-eight patients were enrolled. All women had node-positive, estrogen receptor-positive tumors. At a median follow-up time of 36 months, 45 events had been reported in the tamoxifen group compared with 17 events in the anastrozole group (P = .0002). Disease-free and local recurrence-free survival were also significantly longer in the anastrozole group (hazard ratio [HR] = 0.35; 95% CI, 0.18 to 0.68; P = .001 and HR = 0.15; 95% CI, 0.03 to 0.65; P = .003, respectively). Overall, more adverse events were recorded in the anastrozole group compared with the tamoxifen group (203 v 150, respectively; P = .04). However, more events were life threatening or required hospitalization in the tamoxifen group than in the anastrozole group (33 of 150 events v 28 of 203 events, P = .04).
  
  
  CONCLUSIONS
  Switching to anastrozole after the first 2 to 3 years of treatment is well tolerated and significantly improves event-free and recurrence-free survival in postmenopausal patients with early breast cancer.
authors: National Cancer Research Institute, 16132 Genoa, Italy. f.boccardo@unige.it
authors: Francesco
authors: F
authors: Boccardo
authors: Alessandra
authors: A
authors: Rubagotti
authors: Matteo
authors: M
authors: Puntoni
authors: Pamela
authors: P
authors: Guglielmini
authors: Domenico
authors: D
authors: Amoroso
authors: Angela
authors: A
authors: Fini
authors: Giuseppe
authors: G
authors: Paladini
authors: Mario
authors: M
authors: Mesiti
authors: Domenico
authors: D
authors: Romeo
authors: Michela
authors: M
authors: Rinaldini
authors: Simona
authors: S
authors: Scali
authors: Mauro
authors: M
authors: Porpiglia
authors: Chiara
authors: C
authors: Benedetto
authors: Nunzio
authors: N
authors: Restuccia
authors: Franco
authors: F
authors: Buzzi
authors: Roberto
authors: R
authors: Franchi
authors: Bruno
authors: B
authors: Massidda
authors: Vito
authors: V
authors: Distante
authors: Dino
authors: D
authors: Amadori
authors: Piero
authors: P
authors: Sismondi
mesh_terms: D000328:Adult; D000368:Aged; D000077384:Anastrozole; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008875:Middle Aged; D009570:Nitriles / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D017698:Postmenopause; D011446:Prospective Studies; D016019:Survival Analysis; D013629:Tamoxifen / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D014230:Triazoles / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*
chemical_list: D018931:Antineoplastic Agents, Hormonal; D009570:Nitriles; D014230:Triazoles; D013629:Tamoxifen; D000077384:Anastrozole