Random Forests to Predict Rectal Toxicity Following Prostate Cancer Radiation Therapy

Journal Article · Fri Aug 01 04:00:00 EDT 2014 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/J.IJROBP.2014.04.027· OSTI ID:22420389

Ospina, Juan D. ^[1]; Zhu, Jian ^[1]; Chira, Ciprian ^[2]; Bossi, Alberto ^[3]; Delobel, Jean B. ^[2]; Beckendorf, Véronique ^[4]; Dubray, Bernard ^[5]; Lagrange, Jean-Léon ^[6]; Correa, Juan C. ^[7]; others, and

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1. LTSI, Université de Rennes 1, Rennes (France)
2. Département de Radiothérapie, Centre Eugène Marquis, Rennes (France)
3. Département de Radiothérapie, Institut Gustave-Roussy, Villejuif (France)
4. Département de Radiothérapie, Centre Alexis Vautrin, Nancy (France)
5. Département de Radiothérapie, CRLCC Henri Becquerel, Rouen (France)
6. Département de Radiothérapie, Hôpital Henri Mondor, Créteil (France)
7. Escuela de Estadística, Universidad Nacional de Colombia Sede Medellín, Medellín (Colombia)

Purpose: To propose a random forest normal tissue complication probability (RF-NTCP) model to predict late rectal toxicity following prostate cancer radiation therapy, and to compare its performance to that of classic NTCP models. Methods and Materials: Clinical data and dose-volume histograms (DVH) were collected from 261 patients who received 3-dimensional conformal radiation therapy for prostate cancer with at least 5 years of follow-up. The series was split 1000 times into training and validation cohorts. A RF was trained to predict the risk of 5-year overall rectal toxicity and bleeding. Parameters of the Lyman-Kutcher-Burman (LKB) model were identified and a logistic regression model was fit. The performance of all the models was assessed by computing the area under the receiving operating characteristic curve (AUC). Results: The 5-year grade ≥2 overall rectal toxicity and grade ≥1 and grade ≥2 rectal bleeding rates were 16%, 25%, and 10%, respectively. Predictive capabilities were obtained using the RF-NTCP model for all 3 toxicity endpoints, including both the training and validation cohorts. The age and use of anticoagulants were found to be predictors of rectal bleeding. The AUC for RF-NTCP ranged from 0.66 to 0.76, depending on the toxicity endpoint. The AUC values for the LKB-NTCP were statistically significantly inferior, ranging from 0.62 to 0.69. Conclusions: The RF-NTCP model may be a useful new tool in predicting late rectal toxicity, including variables other than DVH, and thus appears as a strong competitor to classic NTCP models.

• OSTI ID: 22420389
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Journal Name: International Journal of Radiation Oncology, Biology and Physics Journal Issue: 5 Vol. 89; ISSN IOBPD3; ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
ANTICOAGULANTS
NEOPLASMS
PATIENTS
PROSTATE
RADIATION DOSES
RADIOTHERAPY
RECTUM
TOXICITY