title: Prognostic value of the bone scan index using a computer-aided diagnosis system for bone scans in hormone-naive prostate cancer patients with bone metastases.
abstract: BACKGROUND
  The bone scan index (BSI) using a computer-aided diagnosis system for bone scans is expected to be an objective and quantitative clinical tool for evaluating bone metastatic prostate cancer. This study aimed to evaluate the pretreatment BSI as a prognostic factor in hormone-naive prostate cancer patients with bone metastases.
  
  
  METHODS
  The study included 60 patients with hormone-naive, bone metastatic prostate cancer that was initially treated with combined androgen blockade therapy. The BONENAVI system was used for calculating the BSI. We evaluated the correlation between overall survival (OS) and pretreatment clinicopathological characteristics, including patients' age, initial prostate-specific antigen (PSA) value, Gleason scores, clinical TNM stage, and the BSI. Cox proportional hazards regression models were used for statistical analysis.
  
  
  RESULTS
  The median follow-up duration was 21.4 months. Clinical or PSA progression occurred in 37 (61.7%) patients and 18 (30.0%) received docetaxel. Death occurred in 16 (26.7%) patients. Of these deaths, 15 (25.0%) were due to prostate cancer. The median OS was not reached. In multivariate analysis, age and the BSI were independent prognostic factors for OS. We evaluated the discriminatory ability of our models, including or excluding BSI by quantifying the C-index. The BSI improved the C-index from 0.751 to 0.801 for OS. Median OS was not reached in patients with a BSI ≤ 1.9 and median OS was 34.8 months in patients with a BSI >1.9 (p = 0.039).
  
  
  CONCLUSIONS
  The pretreatment BSI and patients' age are independent prognostic factors for patients with hormone-naive, bone metastatic prostate cancer.
authors.affiliation: Department of Urology and Renal Transplantation, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, 232-0024, Japan. miyoyasu@med.yokohama-cu.ac.jp.
authors.forename: Yasuhide
authors.initials: Y
authors.lastname: Miyoshi
authors.affiliation: Department of Urology and Renal Transplantation, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, 232-0024, Japan. apollon831@yahoo.co.jp.
authors.forename: Shuko
authors.initials: S
authors.lastname: Yoneyama
authors.affiliation: Department of Urology and Renal Transplantation, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, 232-0024, Japan. takashi_tk2001@yahoo.co.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kawahara
authors.affiliation: Department of Urology and Renal Transplantation, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, 232-0024, Japan. hatu98@gmail.com.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Hattori
authors.affiliation: Department of Urology and Renal Transplantation, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, 232-0024, Japan. jteran@urahp.yokohama-cu.ac.jp.
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Teranishi
authors.affiliation: Department of Urology and Renal Transplantation, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, 232-0024, Japan. kkurouro@urahp.yokohama-cu.ac.jp.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Kondo
authors.affiliation: Department of Urology, Yokohama Municipal Citizen's Hospital, Yokohama, Japan. shiminmm@yc4.so-net.ne.jp.
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Moriyama
authors.affiliation: Department of Radiology, Yokohama City University Medical Center, Yokohama, Japan. take2922@yokohama-cu.ac.jp.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Takebayashi
authors.affiliation: Department of Urology, Yokohama City University Graduate School of Medicine, Yokohama, Japan. yumiko1@yokohama-cu.ac.jp.
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Yokomizo
authors.affiliation: Department of Urology, Yokohama City University Graduate School of Medicine, Yokohama, Japan. masayao@med.yokohama-cu.ac.jp.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yao
authors.affiliation: Department of Urology and Renal Transplantation, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, 232-0024, Japan. hu0428@med.yokohama-cu.ac.jp.
authors.forename: Hiroji
authors.initials: H
authors.lastname: Uemura
authors.affiliation: Department of Urology and Renal Transplantation, Yokohama City University Medical Center, 4-57 Urafune-cho, Minami-ku, Yokohama, 232-0024, Japan. noguchik@icloud.com.
authors.forename: Kazumi
authors.initials: K
authors.lastname: Noguchi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001859:Bone Neoplasms / Q000175:diagnosis* / Q000188:drug therapy / Q000401:mortality / Q000556:secondary*; D001842:Bone and Bones / Q000473:pathology*; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D000077143:Docetaxel; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000188:drug therapy / Q000401:mortality / Q000473:pathology; D012189:Retrospective Studies; D016019:Survival Analysis; D043823:Taxoids / Q000627:therapeutic use
chemical_list: D000970:Antineoplastic Agents; D043823:Taxoids; D000077143:Docetaxel; D017430:Prostate-Specific Antigen