Pretreatment Nomogram to Predict the Risk of Acute Urinary Retention After I-125 Prostate Brachytherapy

Journal Article · Tue Nov 01 00:00:00 EDT 2011 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/j.ijrobp.2010.06.009· OSTI ID:21590442

Vulpen, Marco van; Battermann, Jan J ^[1]; Roermund, Joep G. van ^[2]; Saibishkumar, Elantholi P ^[3]; Monninkhof, Evelyn M ^[4]

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1. Department of Radiation Oncology, University Medical Center Utrecht (Netherlands)
2. Department of Urology, University Medical Center Utrecht (Netherlands)
3. Department of Radiation Oncology, Princess Margaret Hospital, Toronto, ON (Canada)
4. Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht (Netherlands)

Purpose: Acute urinary retention (AUR) after iodine-125 (I-125) prostate brachytherapy negatively influences long-term quality of life and therefore should be prevented. We aimed to develop a nomogram to preoperatively predict the risk of AUR. Methods: Using the preoperative data of 714 consecutive patients who underwent I-125 prostate brachytherapy between 2005 and 2008 at our department, we modeled the probability of AUR. Multivariate logistic regression analysis was used to assess the predictive ability of a set of pretreatment predictors and the additional value of a new risk factor (the extent of prostate protrusion into the bladder). The performance of the final model was assessed with calibration and discrimination measures. Results: Of the 714 patients, 57 patients (8.0%) developed AUR after implantation. Multivariate analysis showed that the combination of prostate volume, IPSS score, neoadjuvant hormonal treatment and the extent of prostate protrusion contribute to the prediction of AUR. The discriminative value (receiver operator characteristic area, ROC) of the basic model (including prostate volume, International Prostate Symptom Score, and neoadjuvant hormonal treatment) to predict the development of AUR was 0.70. The addition of prostate protrusion significantly increased the discriminative power of the model (ROC 0.82). Calibration of this final model was good. The nomogram showed that among patients with a low sum score (<18 points), the risk of AUR was only 0%-5%. However, in patients with a high sum score (>35 points), the risk of AUR was more than 20%. Conclusion: This nomogram is a useful tool for physicians to predict the risk of AUR after I-125 prostate brachytherapy. The nomogram can aid in individualized treatment decision-making and patient counseling.

• OSTI ID: 21590442
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Vol. 81, Issue 3; Other Information: DOI: 10.1016/j.ijrobp.2010.06.009; PII: S0360-3016(10)00818-7; Copyright (c) 2011 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
BLADDER
BRACHYTHERAPY
CALIBRATION
DECISION MAKING
FORECASTING
HAZARDS
HORMONES
IODINE 125
MULTIVARIATE ANALYSIS
NEOPLASMS
NOMOGRAMS
PERFORMANCE
PROSTATE
REGRESSION ANALYSIS
RETENTION
STANDARD OF LIVING
SYMPTOMS
TOXICITY
BETA DECAY RADIOISOTOPES
BODY
DAYS LIVING RADIOISOTOPES
DIAGRAMS
DISEASES
ELECTRON CAPTURE RADIOISOTOPES
GLANDS
INFORMATION
INTERMEDIATE MASS NUCLEI
INTERNAL CONVERSION RADIOISOTOPES
IODINE ISOTOPES
ISOTOPES
MALE GENITALS
MATHEMATICS
MEDICINE
NUCLEAR MEDICINE
NUCLEI
ODD-EVEN NUCLEI
ORGANS
RADIOISOTOPES
RADIOLOGY
RADIOTHERAPY
STATISTICS
THERAPY
URINARY TRACT