title: Nine weeks versus 1 year adjuvant trastuzumab in patients with early breast cancer: an observational study by the Turkish Oncology Group (TOG).
abstract: BACKGROUND
  Optimal duration of adjuvant trastuzumab in early breast cancer is an unresolved issue. In this observational study, we compared the outcome of 9 weeks and 1 year adjuvant trastuzumab in early breast cancer patients in Turkey.
  
  
  METHODS
  Records of 680 patients with HER2-positive early breast cancer who received adjuvant trastuzumab plus chemotherapy were obtained and patients were followed up to compare the disease-free survival (DFS) outcome of 9 weeks versus 1 year trastuzumab.
  
  
  RESULTS
  Nine weeks and 1 year trastuzumab was given to 202 (29.7 %) and 478 (70.3 %) patients, respectively. There was a significantly lower rate of patients with negative lymph nodes in the 9-week trastuzumab group. At median 3 years of follow-up from the date of starting trastuzumab, the DFS rates were 88.6 and 85.6 %, respectively (p = 0.670). When adjusted for all the prognostic factors that were significant on univariate analysis, again there was no significant difference in DFS between the groups (HR 0.675; 95 % CI 0.370-1.231; p = 0.200). Cardiac toxicity defined as a ≥15 % decrease in LVEF was significantly higher in the 1-year trastuzumab group (1.88 % versus none for 1-year and 9-week trastuzumab groups, respectively; p = 0.050).
  
  
  CONCLUSIONS
  The results of this observational study suggest that DFS outcome of 9 weeks of adjuvant trastuzumab may be comparable to 1 year adjuvant trastuzumab: this needs confirmation by randomized trials.
authors: Ankara Üniversitesi Tıp Fakültesi; Tıbbi Onkoloji BD, Dikimevi, Ankara, 06590, Turkey, icli@medicine.ankara.edu.tr.
authors: Fikri
authors: F
authors: İçli
authors: Kadri
authors: K
authors: Altundağ
authors: Hakan
authors: H
authors: Akbulut
authors: Semra
authors: S
authors: Paydaş
authors: Gül
authors: G
authors: Başaran
authors: Pınar
authors: P
authors: Saip
authors: Gamze G
authors: GG
authors: Doğu
authors: Yeşim
authors: Y
authors: Eralp
authors: Rüçhan
authors: R
authors: Uslu
authors: Alper
authors: A
authors: Sevinç
authors: Handan
authors: H
authors: Onur
authors: Nil M
authors: NM
authors: Mandel
authors: Canfeza
authors: C
authors: Sezgin
authors: Mustafa
authors: M
authors: Altınbaş
authors: Nilüfer
authors: N
authors: Güler
authors: Abdurrahman
authors: A
authors: Işıkdoğan
authors: Erhan
authors: E
authors: Gökmen
authors: Kazım
authors: K
authors: Uygun
authors: Zeki
authors: Z
authors: Üstüner
authors: Arzu
authors: A
authors: Yaren
authors: Binnaz
authors: B
authors: Demirkan
authors: Uğur
authors: U
authors: Coşkun
authors: Alper
authors: A
authors: Ata
authors: Metin
authors: M
authors: Özkan
authors: Ali
authors: A
authors: Arican
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D066126:Cardiotoxicity / Q000209:etiology; D017024:Chemotherapy, Adjuvant; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis / Q000473:pathology; D008875:Middle Aged; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D000068878:Trastuzumab / Q000008:administration & dosage / Q000009:adverse effects; D016896:Treatment Outcome; D014421:Turkey; D055815:Young Adult
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab; C508053:ERBB2 protein, human