title: The role of IGF-1 and the distribution of body fat in decreasing the number of prostate rebiopsies.
abstract: OBJECTIVE
  To assess the usefulness of IGF-1 and internal organ fat measured by bioelectrical impedance audiometry to avoid rebiopsies in patients with persistently high prostate-specific antigen (PSA) levels.
  
  
  METHODS
  A prospective study was conducted with 92 patients who underwent prostate rebiopsy due to high PSA levels with negative results in the rectal examination and a lack of preneoplastic lesions. The patients previously had their IGF-1 levels measured and had undergone an impedance audiometry test using the abdominal Fat Analyser AB-140 TANITA system. We calculated the receiver operating characteristic (ROC) curves for the PSA levels, %PSA, internal organ fat and IGF-1 and PSA density.
  
  
  RESULTS
  Twenty-five patients were diagnosed with prostate cancer. These patients had significantly higher PSA, PSAd and IGF-1 values and a tendency towards higher internal organ fat levels and lower %PSA readings (p=.001, p=.003, p=.001, p=.24 and P=0.28, respectively). The ROC curve showed an area under the curve for IGF-1 and PSA of .82 and .81, respectively. Using the cutoff points for 95% sensitivity and using the 3 criteria as an indication of rebiopsy, 74% of the biopsies would have been spared, leaving undiagnosed only 1 patient with clinically significant cancer -Gleason score>7 (4+3)-. The positive and negative predictive values for the set of variables were higher than for each one separately (PPV: 66/NPV: 63). The cost of both determinations was 82 euros.
  
  
  CONCLUSIONS
  Our results suggest that measuring IGF-1 could significantly decrease the number of unnecessary rebiopsies in an inexpensive and safe manner.
authors.affiliation: Servicio de Urología, Hospital Universitario y Politécnico La Fe, Valencia, España. Electronic address: edumoranpascual@gmail.com.
authors.forename: E
authors.initials: E
authors.lastname: Morán
authors.affiliation: Servicio de Urología, Hospital Universitario y Politécnico La Fe, Valencia, España.
authors.forename: M
authors.initials: M
authors.lastname: Martínez
authors.affiliation: Servicio de Urología, Hospital Universitario y Politécnico La Fe, Valencia, España.
authors.forename: A
authors.initials: A
authors.lastname: Budía
authors.affiliation: Servicio de Urología, Hospital Universitario y Politécnico La Fe, Valencia, España.
authors.forename: E
authors.initials: E
authors.lastname: Broseta
authors.affiliation: Servicio de Endocrinología, Hospital Universitario y Politécnico La Fe, Valencia, España.
authors.forename: R
authors.initials: R
authors.lastname: Cámara
authors.affiliation: Servicio de Urología, Hospital Universitario y Politécnico La Fe, Valencia, España.
authors.forename: F
authors.initials: F
authors.lastname: Boronat
mesh_terms: D000273:Adipose Tissue; D000368:Aged; D001706:Biopsy / Q000706:statistics & numerical data; D017097:Electric Impedance; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011467:Prostate / Q000473:pathology*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000473:pathology*
chemical_list: D007334:Insulin-Like Growth Factor I
keywords: Cáncer de próstata; Insuline growth factor-1; Obesidad; Obesity; Prostate cancer; Rebiopsia; Rebiopsy