title: Impact of body mass index on neoadjuvant treatment outcome: a pooled analysis of eight prospective neoadjuvant breast cancer trials.
abstract: Obesity is associated with an increased risk of breast cancer (BC) and poorer outcome. We assessed the impact of body mass index (BMI) on pathological complete response (pCR), disease-free (DFS), and overall survival (OS), according to BC subtypes in patients with primary BC treated with neoadjuvant chemotherapy. 8,872 patients with primary BC from eight neoadjuvant trials were categorized according to BMI: underweight (<18.5 kg/m(2)), normal weight (18.5 to <25 kg/m(2)), overweight (25 to <30 kg/m(2)), obese (30 to <40 kg/m(2)), and very obese (≥40 kg/m(2)). BC subtypes were defined as luminal-like (ER/PgR-positive and HER2-negative), HER2/luminal (ER/PgR-positive and HER2-positive), HER2-like (ER/PgR-negative and HER2-positive), and triple-negative (TNBC; ER/PgR- and HER2-negative). pCR rate was higher in normal weight patients compared with all other BMI groups (P = 0.003). Mean DFS and OS were shorter in obese (87.3 months, P = 0.014 and 94.9 months, P = 0.001, respectively) and very obese (66.6 months, P < 0.001 and 75.3 months, P < 0.001, respectively) compared with normal weight patients (91.5 and 98.8 months, respectively) which was confirmed by subpopulation treatment effect pattern plot analyses and was consistent in luminal-like and TNBC. No interaction was observed between BMI and pCR. Normal weight patients experienced less non-hematological adverse events (P = 0.002) and were more likely to receive full taxane doses (P < 0.001) compared with all other BMI groups. In multivariable analysis, the dose of taxanes was predictive for pCR (P < 0.001). Higher BMI was associated with lower pCR and a detrimental impact on survival. Normal weight patients had the best compliance to chemotherapy and received the highest taxane doses, which seems to be related with treatment outcomes.
authors: German Breast Group, Neu-Isenburg, Germany, fontanella.caterina@spes.uniud.it.
authors: Caterina
authors: C
authors: Fontanella
authors: Bianca
authors: B
authors: Lederer
authors: Stephan
authors: S
authors: Gade
authors: Mieke
authors: M
authors: Vanoppen
authors: Jens Uwe
authors: JU
authors: Blohmer
authors: Serban Dan
authors: SD
authors: Costa
authors: Carsten
authors: C
authors: Denkert
authors: Holger
authors: H
authors: Eidtmann
authors: Bernd
authors: B
authors: Gerber
authors: Claus
authors: C
authors: Hanusch
authors: Jörn
authors: J
authors: Hilfrich
authors: Jens
authors: J
authors: Huober
authors: Andreas
authors: A
authors: Schneeweiss
authors: Stefan
authors: S
authors: Paepke
authors: Christian
authors: C
authors: Jackisch
authors: Keyur
authors: K
authors: Mehta
authors: Valentina
authors: V
authors: Nekljudova
authors: Michael
authors: M
authors: Untch
authors: Patrick
authors: P
authors: Neven
authors: Gunter
authors: G
authors: von Minckwitz
authors: Sibylle
authors: S
authors: Loibl
mesh_terms: D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D014408:Biomarkers, Tumor; D015992:Body Mass Index; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000401:mortality / Q000473:pathology; D005260:Female; D006801:Humans; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D060787:Neoplasm Grading; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor