title: Body mass index was associated with upstaging and upgrading in patients with low-risk prostate cancer who met the inclusion criteria for active surveillance.
abstract: BACKGROUND
  Obesity is associated with an increased risk of high-grade prostate cancer (PCa). The effect of body mass index (BMI) as a predictor of progression in men with low-risk PCa has been only poorly assessed. In this study, we evaluated the association of BMI with progression in patients with low-risk PCa who met the inclusion criteria for the active surveillance (AS) protocol.
  
  
  METHODS
  We assessed 311 patients who underwent radical prostatectomy and were eligible for AS according to the following criteria: clinical stage T2a or less, prostate-specific antigen level < 10 ng/ml, 2 or fewer cores involved with cancer, Gleason score ≤ 6 grade, and prostate-specific antigen density < 0.2 ng/ml/cc. Reclassification was defined as upstaged (pathological stage > pT2) and upgraded (Gleason score ≥ 7; primary Gleason pattern 4) disease. Seminal vesicle invasion, positive lymph nodes, and tumor volume ≥ 0.5 ml were also recorded.
  
  
  RESULTS
  We found that high BMI was significantly associated with upgrading, upstaging, and seminal vesicle invasion, whereas it was not associated with positive lymph nodes or large tumor volume. At multivariate analysis, 1 unit increase of BMI significantly increased the risk of upgrading, upstaging, seminal vesicle invasion, and any outcome by 21%, 23%, 27%, and 20%, respectively. The differences between areas under the receiver operating characteristics curves comparing models with and without BMI were statistically significant for upgrading (P = 0.0002), upstaging (P = 0.0007), and any outcome (P = 0.0001).
  
  
  CONCLUSIONS
  BMI should be a selection criterion for inclusion of patients with low-risk PCa in AS programs. Our results support the idea that obesity is associated with worse prognosis and suggest that a close AS program is an appropriate treatment option for obese subjects.
authors: Division of Urology, European Institute of Oncology, Milan, Italy.
authors: Ottavio
authors: O
authors: de Cobelli
authors: Department of Translational Medical Sciences, University "Federico II", Naples, Italy.
authors: Daniela
authors: D
authors: Terracciano
authors: Division of Epidemiology and Biostatistics, European Institute of Oncology, Milan, Italy.
authors: Elena
authors: E
authors: Tagliabue
authors: Division of Epidemiology and Biostatistics, European Institute of Oncology, Milan, Italy.
authors: Sara
authors: S
authors: Raimondi
authors: Division of Urology, European Institute of Oncology, Milan, Italy.
authors: Giacomo
authors: G
authors: Galasso
authors: Division of Urology, European Institute of Oncology, Milan, Italy.
authors: Antonio
authors: A
authors: Cioffi
authors: Division of Urology, European Institute of Oncology, Milan, Italy.
authors: Giovanni
authors: G
authors: Cordima
authors: Division of Urology, European Institute of Oncology, Milan, Italy.
authors: Gennaro
authors: G
authors: Musi
authors: Division of Urology, Magna Graecia University of Catanzaro, Catanzaro, Italy.
authors: Rocco
authors: R
authors: Damiano
authors: Division of Urology, Magna Graecia University of Catanzaro, Catanzaro, Italy.
authors: Francesco
authors: F
authors: Cantiello
authors: Division of Urology, European Institute of Oncology, Milan, Italy.
authors: Serena
authors: S
authors: Detti
authors: Division of Urology, European Institute of Oncology, Milan, Italy.
authors: Deliu
authors: D
authors: Victor Matei
authors: Division of Urology, European Institute of Oncology, Milan, Italy.
authors: Danilo
authors: D
authors: Bottero
authors: Division of Pathology, European Institute of Oncology, Milan, Italy.
authors: Giuseppe
authors: G
authors: Renne
authors: Division of Urology, European Institute of Oncology, Milan, Italy. Electronic address: matteo.ferro@ieo.it.
authors: Matteo
authors: M
authors: Ferro
mesh_terms: D015992:Body Mass Index; D018450:Disease Progression; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications*; D017430:Prostate-Specific Antigen / Q000378:metabolism*; D011471:Prostatic Neoplasms / Q000209:etiology* / Q000473:pathology / Q000601:surgery; D062486:Public Health Surveillance; D012189:Retrospective Studies; D012306:Risk
chemical_list: D017430:Prostate-Specific Antigen
keywords: Active surveillance; Body mass index; Prostate cancer