Predictive factors for urinary toxicity after iodine-125 prostate brachytherapy with or without supplemental external beam radiotherapy

Takahisa Eriguchi, Atsunori Yorozu, Nobuko Kuroiwa, Yasuto Yagi, Toru Nishiyama, Shiro Saito, Kazuhito Toya, Takashi Hanada, Yutaka Shiraishi, Toshio Ohashi, Naoyuki Shigematsu

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12 Citations (Scopus)


Purpose: We examined the factors associated with urinary toxicities because of brachytherapy with iodine-125 with or without supplemental external beam radiotherapy (EBRT) for prostate cancer. Methods and Materials: We investigated 1313 patients with localized prostate cancer treated with iodine-125 brachytherapy with or without supplemental EBRT between 2003 and 2009. The International Prostate Symptom Score (IPSS) and Common Terminology Criteria for Adverse Events data were prospectively determined. Patients, treatment, and implant factors were investigated for their association with urinary toxicity or symptoms. Results: IPSS resolution was not associated with biologically effective dose (BED). Baseline IPSS, total needles, and the minimal dose received by 30% of the urethra had the greatest effect according to multivariate analysis (MVA). Urinary symptom flare was associated with baseline IPSS, age, BED, and EBRT on MVA. Urinary symptom flare and urinary Grade 2 or higher (G2+) toxicity occurred in 51%, 58%, and 67% (p = 0.025) and 16%, 22%, and 20% (p = 0.497) of the 220 Gy BED groups, respectively. Urinary G2+ toxicity was associated with baseline IPSS, neoadjuvant androgen deprivation therapy (NADT), and seed density on MVA. When we divided patients into four groups according to prostate volume (

Original languageEnglish
Publication statusAccepted/In press - 2015 Oct 29



  • I
  • Brachytherapy
  • Higher biological effective dose
  • Neoadjuvant androgen deprivation therapy
  • Prostate cancer
  • Supplemental external beam radiotherapy
  • Urinary toxicity

ASJC Scopus subject areas

  • Oncology
  • Radiology Nuclear Medicine and imaging

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