title: Body mass index and clinical benefit of fulvestrant in postmenopausal women with advanced breast cancer.
abstract: OBJECTIVE
  Obesity is a known risk factor for breast cancer and has been linked to increased risk of recurrence and death in breast cancer patients. Little is known about the predictive value of obesity. As endocrine therapy is widely used for breast cancer treatment worldwide, we aimed at correlating baseline body mass index (BMI) with clinical benefit derived from fulvestrant in postmenopausal women with advanced breast cancer.
  
  
  METHODS
  We analyzed consecutive patients treated with fulvestrant in our center between January 2009 and March 2015. Patients were categorized as normal (BMI 18.5-24.9 kg/m2), overweight (BMI 25-29 kg/m2) and obese (BMI &gt;30 kg/m2). The antitumor activity of fulvestrant was evaluated in terms of the clinical benefit rate (CBR).
  
  
  RESULTS
  Seventy-five consecutive patients matched the eligibility criteria for analysis. Fulvestrant was administered as first-line therapy in 4 (5%) cases, as second line in 27 (36%) and as third line and beyond in 44 (59%) cases. According to BMI, 44 (59%) patients were classified as normal weight, 19 (25%) as overweight, and 12 (16%) as obese. No difference in estrogen receptor expression was found in relation to BMI. CBR was 53% overall, but rose to 70.5% in normal-weight patients and dropped to 31.6% and 25% in overweight and obese patients, respectively (p&lt;0.001).
  
  
  CONCLUSIONS
  Increased BMI has a negative influence on treatment outcome. Even with the limitation of the relatively small sample size, it appears that patients of normal weight are 2.5-fold more likely to benefit from fulvestrant as overweight and obese patients.
authors.affiliation: Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan - Italy.
authors.forename: Arpine
authors.initials: A
authors.lastname: Gevorgyan
authors.affiliation: Medical Oncology Department, IRCCS AOU S. Martino-IST, Genoa - Italy.
authors.forename: Giacomo
authors.initials: G
authors.lastname: Bregni
authors.affiliation: Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan - Italy.
authors.forename: Giulia
authors.initials: G
authors.lastname: Galli
authors.affiliation: Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan - Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Ganzinelli
authors.affiliation: Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan - Italy.
authors.forename: Antonia
authors.initials: A
authors.lastname: Martinetti
authors.affiliation: Clinical Epidemiology and Trials Organization Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan - Italy.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Lo Vullo
authors.affiliation: Clinical Epidemiology and Trials Organization Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan - Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Mariani
authors.affiliation: Farmacy Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan - Italy.
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Festinese
authors.affiliation: Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan - Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Sottotetti
authors.affiliation: Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan - Italy.
authors.forename: Filippo
authors.initials: F
authors.lastname: de Braud
authors.affiliation: Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan - Italy.
authors.forename: Serena
authors.initials: S
authors.lastname: Di Cosimo
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D014408:Biomarkers, Tumor; D015992:Body Mass Index; D001943:Breast Neoplasms / Q000150:complications / Q000188:drug therapy* / Q000473:pathology*; D004958:Estradiol / Q000031:analogs & derivatives* / Q000627:therapeutic use; D005260:Female; D000077267:Fulvestrant; D006801:Humans; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D009765:Obesity / Q000150:complications; D017698:Postmenopause; D011960:Receptors, Estrogen / Q000378:metabolism; D012307:Risk Factors; D016896:Treatment Outcome
chemical_list: D018931:Antineoplastic Agents, Hormonal; D014408:Biomarkers, Tumor; D011960:Receptors, Estrogen; D000077267:Fulvestrant; D004958:Estradiol