title: Efficacy of tamoxifen ± aminoglutethimide in normal weight and overweight postmenopausal patients with hormone receptor-positive breast cancer: an analysis of 1509 patients of the ABCSG-06 trial.
abstract: BACKGROUND
  There exists evidence that body mass index (BMI) impacts on the efficacy of aromatase inhibitors in patients with breast cancer. The relationship between BMI and the efficacy of tamoxifen is conflicting. We investigated the impact of BMI on the efficacy of single tamoxifen and tamoxifen plus an aromatase inhibitor in the well-defined prospective study population of the ABCSG-06 trial.
  
  
  METHODS
  ABCSG-06 investigated the efficacy of tamoxifen vs tamoxifen plus aminoglutethimide in postmenopausal women with hormone receptor-positive breast cancer. Taking BMI at baseline, patients were classified as normal weight (BMI=18.5-24.9 kg m(-)(2)), overweight (BMI=25-29.9 kg m(-)(2)), and obese (30 kg m(-)(2)) according to WHO criteria.
  
  
  RESULTS
  Overweight+obese patients had an increased risk for distant recurrences (hazard ratio (HR): 1.51; Cox P=0·018) and a worse overall survival (OS; HR: 1·49; Cox P=0·052) compared with normal weight patients. Analysing patients treated with single tamoxifen only, no difference between overweight+obese patients and normal weight patients regarding distant recurrence-free survival (HR: 1.35; Cox P=0·24) and OS (HR: 0.99; Cox P=0·97) could be observed. In contrast, in the group of patients treated with the combination of tamoxifen plus aminoglutethimide, overweight+obese patients had an increased risk for distant recurrences (1.67; Cox P=0·03) and a worse OS (1.47; Cox P=0·11) compared with normal weight patients.
  
  
  CONCLUSIONS
  BMI impacts on the efficacy of aromatase inhibitor-based treatment but not single tamoxifen.
authors.affiliation: Division of Gynecology and Gynecological Oncology, Department of Obstetrics and Gynecology, Comprehensive Cancer Center Vienna, Medical University of Vienna, Vienna, Austria.
authors.forename: G
authors.initials: G
authors.lastname: Pfeiler
authors.forename: H
authors.initials: H
authors.lastname: Stöger
authors.forename: P
authors.initials: P
authors.lastname: Dubsky
authors.forename: B
authors.initials: B
authors.lastname: Mlineritsch
authors.forename: C
authors.initials: C
authors.lastname: Singer
authors.forename: M
authors.initials: M
authors.lastname: Balic
authors.forename: F
authors.initials: F
authors.lastname: Fitzal
authors.forename: M
authors.initials: M
authors.lastname: Moik
authors.forename: W
authors.initials: W
authors.lastname: Kwasny
authors.forename: U
authors.initials: U
authors.lastname: Selim
authors.forename: K
authors.initials: K
authors.lastname: Renner
authors.forename: F
authors.initials: F
authors.lastname: Ploner
authors.forename: G G
authors.initials: GG
authors.lastname: Steger
authors.forename: M
authors.initials: M
authors.lastname: Seifert
authors.forename: F
authors.initials: F
authors.lastname: Hofbauer
authors.forename: P
authors.initials: P
authors.lastname: Sandbichler
authors.forename: H
authors.initials: H
authors.lastname: Samonigg
authors.forename: R
authors.initials: R
authors.lastname: Jakesz
authors.forename: R
authors.initials: R
authors.lastname: Greil
authors.forename: C
authors.initials: C
authors.lastname: Fesl
authors.forename: M
authors.initials: M
authors.lastname: Gnant
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000616:Aminoglutethimide / Q000008:administration & dosage / Q000009:adverse effects; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000009:adverse effects / Q000627:therapeutic use*; D047072:Aromatase Inhibitors / Q000008:administration & dosage / Q000009:adverse effects; D015992:Body Mass Index; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D005260:Female; D006801:Humans; D008875:Middle Aged; D050177:Overweight / Q000503:physiopathology*; D017698:Postmenopause; D011446:Prospective Studies; D011956:Receptors, Cell Surface / Q000096:biosynthesis; D013629:Tamoxifen / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D018931:Antineoplastic Agents, Hormonal; D047072:Aromatase Inhibitors; D011956:Receptors, Cell Surface; D013629:Tamoxifen; D000616:Aminoglutethimide