title: Obesity as an independent risk factor for decreased survival in node-positive high-risk breast cancer.
abstract: Obese breast cancer patients have a higher risk of lymph node metastasis and a poorer prognosis compared to patients with normal weight. For obese women with node-positive breast cancer, an association between body weight and prognosis remains unclear. In this retrospective study, we analyzed patient data from the Phase-III ADEBAR trial, in which high-risk breast cancer patients (pT1-4, pN2-3, pM0) were randomized into a docetaxel-based versus epirubicin-based chemotherapy regimen. Patients were grouped according to their BMI value as underweight/normal weight (BMI < 25 kg/m(2); n = 543), overweight (BMI 25-29.9 kg/m(2); n = 482) or obese (BMI ≥ 30 kg/m(2); n = 285). Overweight and obese patients were older, had larger tumors and were more likely to be postmenopausal at the time of diagnosis compared to underweight/normal-weight patients (all p < 0.001). Multivariate Cox regression analyses adjusting for age and histopathological tumor features showed that obese patients had a significantly shorter disease-free survival (DFS; HR 1.43; 95 % CI 1.11-1.86; p = 0.006) and overall survival (OS; HR 1.56; 95 % CI 1.14-2.14; p = 0.006) than non-obese patients. Subgroup analyses revealed that the differences in DFS and OS were significant for postmenopausal but not for premenopausal patients, and that the survival benefit of non-obese patients was more pronounced in women with hormone-receptor-positive disease. Obesity constitutes an independent, adverse prognostic factor in high-risk node-positive breast cancer patients, in particular for postmenopausal women and women with hormone-receptor-positive disease.
authors.affiliation: Frauenklinik der Universität Ulm, Prittwitzstraße 43, 89075, Ulm, Germany, christoph.scholz@uniklinik-ulm.de.
authors.forename: Christoph
authors.initials: C
authors.lastname: Scholz
authors.forename: U
authors.initials: U
authors.lastname: Andergassen
authors.forename: P
authors.initials: P
authors.lastname: Hepp
authors.forename: C
authors.initials: C
authors.lastname: Schindlbeck
authors.forename: Thomas W P
authors.initials: TW
authors.lastname: Friedl
authors.forename: N
authors.initials: N
authors.lastname: Harbeck
authors.forename: M
authors.initials: M
authors.lastname: Kiechle
authors.forename: H
authors.initials: H
authors.lastname: Sommer
authors.forename: H
authors.initials: H
authors.lastname: Hauner
authors.forename: K
authors.initials: K
authors.lastname: Friese
authors.forename: B
authors.initials: B
authors.lastname: Rack
authors.forename: W
authors.initials: W
authors.lastname: Janni
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D014408:Biomarkers, Tumor; D015992:Body Mass Index; D001943:Breast Neoplasms / Q000150:complications* / Q000188:drug therapy / Q000401:mortality* / Q000473:pathology; D017326:Clinical Trials, Phase III as Topic; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008207:Lymphatic Metastasis; D009367:Neoplasm Staging; D009765:Obesity / Q000150:complications*; D011379:Prognosis; D016032:Randomized Controlled Trials as Topic; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D014408:Biomarkers, Tumor