The effect of body mass index on overall and disease-free survival in node-positive breast cancer patients treated with docetaxel and doxorubicin-containing adjuvant chemotherapy: the experience of the BIG 02-98 trial

Evandro Azambuja (1) , Worta Mccaskill-Stevens (2) , Prudence Francis (3, 4, 5) , Emmanuel Quinaux (6) , John P. A. Crown (7) , Malou Vicente (8) , Rosa Giuliani (9) , Bo Nordenskjöld (10) , Jorge Gutiérez (11) , Michael Andersson (12) , Mireia Margeli Vila (13) , Raimund Jakesz (14) , Jan Demol (15) , Joanna Dewar (16) , Armando Santoro (17) , Ana Lluch (18) , Steven Olsen (19) , Richard D. Gelber (20) , Angelo Di Leo (21) , Martine Piccart-Gebhart (1)

1 Institut Jules Bordet [Bruxelles]
2 National Cancer Institute, National Institutes of Health
3 Peter MacCallum Cancer Centre and St Vincent's Hospital, Australian New Zealand Breast Cancer Trials Group
4 Australian New Zealand Breast Cancer Trials Group
5 International Breast Cancer Study Group
6 IDDI - International Drug Development Institute
7 St. Vincent's Hospital
8 Br.E.A.S.T. Data Centre
9 Medical Oncology Unit
10 Universitetssjukhuset, Oncology
11 Clinica Las Condes
12 Department of Oncology, The Finsen Centre
13 Hospital Germans Trias I Pujol
14 University of Vienna, General Hospital
15 Heilig Hart Ziekenhuis
16 Sir Charles Gairdner Hospital
17 IRCCS Milan - Istituto Clinico Humanitas [Milan]
18 Hospital Clinico Universitario
19 Sanofi-aventis
20 Department of Biostatistics and Computational Biology
21 Sandro Pitigliani Medical Oncology Unit

Background: Obesity has been shown to be an indicator of poor prognosis for patients with primary breast cancer (BC) regardless of the use of adjuvant systemic therapy. Patients and methods: This is a retrospective analysis of 2,887 node-positive BC patients enrolled in the BIG 02-98 adjuvant study, a randomised phase III trial whose primary objective was to evaluate disease-free survival (DFS) by adding docetaxel to doxorubicin-based chemotherapy. In the current analysis, the effect of body mass index (BMI) on DFS and overall survival (OS) was assessed. BMI was obtained before the first cycle of chemotherapy. Obesity was defined as a BMI ≥ 30 kg/m². Results: In total, 547 (19%) patients were obese at baseline, while 2,340 (81%) patients were non-obese. Estimated 5-year OS was 87.5% for non-obese and 82.9% for obese patients (HR 1.34;  = 0.013). Estimated 5-years DFS was 75.9% for non-obese and 70.0% for obese patients (HR 1.20;  = 0.041). In a multivariate model, obesity remained an independent prognostic factor for OS and DFS. Conclusions: In this study, obesity was associated with poorer outcome in node-positive BC patients. Given the increasing prevalence of obesity worldwide, more research on improving the treatment of obese BC patients is needed.

Mots clés: Breast cancer; Obesity; BMI; Adjuvant chemotherapy; Docetaxel; Node-positive

Evandro Azambuja, Worta Mccaskill-Stevens, Prudence Francis, Emmanuel Quinaux, John P. A. Crown, et al.. The effect of body mass index on overall and disease-free survival in node-positive breast cancer patients treated with docetaxel and doxorubicin-containing adjuvant chemotherapy: the experience of the BIG 02-98 trial. Breast Cancer Research and Treatment, 2009, 119 (1), pp.145-153. ⟨10.1007/s10549-009-0512-0⟩. ⟨hal-00535391⟩