title: Large prostate gland size is not a contraindication to low-dose-rate brachytherapy for prostate adenocarcinoma.
abstract: OBJECTIVE
  Prostate volume greater than 50cc is traditionally a relative contraindication to prostate seed implantation (PSI), but there is little consensus regarding prostate size and clinical outcomes. We report biochemical control and toxicity after low-dose-rate PSI and compare outcomes according to the prostate size.
  
  
  METHODS
  A total of 429 men who underwent low-dose-rate PSI between 1998 and 2009 were evaluated. Median followup was 38.7 months. Patients were classified by prostate volume into small, medium, and large subgroups. Differences were analyzed using the Mann-Whitney and Pearson's χ(2) tests for continuous and categorical variables, respectively. Cox proportional hazards regression models were used to evaluate effect of prostate size on outcomes.
  
  
  RESULTS
  Patient pretreatment factors were balanced between groups except for age (p=0.001). The 10-year actuarial freedom from biochemical failure for all patients treated with PSI was 96.3% with no statistically significant difference between large vs. small/medium prostate size (90% vs. 96.6%, p=0.47). In a multivariate analysis, plan type (hazard ratio [HR]=0.25, p=0.03), dose to 90% of the gland (D90: HR=0.98, p=0.02), volume receiving 200Gy (V200: HR=0.98, p=0.026), and biologic effective dose (HR=0.99, p=0.045), but not prostate size (HR=2.27, p=0.17) were significantly associated with freedom from biochemical failure. Prostate size was not significantly associated with time to maximum American Urologic Association score.
  
  
  CONCLUSIONS
  In men with large prostates, the PSI provides biochemical control and temporal changes in genitourinary toxicity that are comparable with men having smaller glands. Accurate dose optimization and delivery of PSI provides the best clinical outcomes regardless of gland size.
authors: Department of Radiation Oncology, Kimmel Cancer Center and Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA. Electronic address: jkosjc@gmail.com.
authors: Kosj
authors: K
authors: Yamoah
authors: Department of Radiation Oncology, Kimmel Cancer Center and Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA.
authors: Harriet B
authors: HB
authors: Eldredge-Hindy
authors: Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA.
authors: Nicholas G
authors: NG
authors: Zaorsky
authors: Department of Radiation Oncology, Kimmel Cancer Center and Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA.
authors: Joshua D
authors: JD
authors: Palmer
authors: Department of Radiation Oncology, Kimmel Cancer Center and Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA.
authors: Laura A
authors: LA
authors: Doyle
authors: Division of Biostatistics, Department of Pharmacology and Experimental Therapeutics, Kimmel Cancer Center and Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA.
authors: Jocelyn A
authors: JA
authors: Sendecki
authors: Department of Radiation Oncology, Kimmel Cancer Center and Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA.
authors: Adam A
authors: AA
authors: Hesney
authors: Department of Radiation Oncology, Kimmel Cancer Center and Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA.
authors: Logan
authors: L
authors: Harper
authors: Department of Radiation Oncology, Kimmel Cancer Center and Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA.
authors: Michael
authors: M
authors: Repka
authors: Department of Radiation Oncology, University of Virginia, Charlottesville, VA.
authors: Timothy N
authors: TN
authors: Showalter
authors: Department of Radiation Oncology, Kimmel Cancer Center and Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA.
authors: Mark D
authors: MD
authors: Hurwitz
authors: Department of Radiation Oncology, Kimmel Cancer Center and Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA.
authors: Adam P
authors: AP
authors: Dicker
authors: Department of Radiation Oncology, Kimmel Cancer Center and Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA.
authors: Robert B
authors: RB
authors: Den
mesh_terms: D000230:Adenocarcinoma / Q000097:blood / Q000532:radiotherapy*; D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood; D001918:Brachytherapy / Q000009:adverse effects / Q000379:methods; D000075202:Contraindications; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009929:Organ Size; D016016:Proportional Hazards Models; D011467:Prostate / Q000033:anatomy & histology*; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000532:radiotherapy*; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor; D017430:Prostate-Specific Antigen
keywords: Biochemical control; Brachytherapy; Low-dose rate; Prostate cancer