Abstract Purpose To perform bladder dose-surface map (DSM) analysis for (1) identifying symptom-related sub-surfaces (Ssurf) and evaluating their prediction capability of urinary toxicity, (2) comparing DSM with dose-volume map (DVM) (method effect), and (3) assessing the reproducibility of DSM (cohort effect). Methods and materials Urinary toxicities were prospectively analyzed for 254 prostate cancer patients treated with IMRT/IGRT at 78/80 Gy. DSMs were generated by unfolding bladder surfaces in a 2D plane. Pixel-by-pixel analysis was performed to identify symptom-related Ssurf. Likewise, voxel-by-voxel DVM analysis was performed to identify sub-volumes (Svol). The prediction capability of Ssurf and Svol DVHs was assessed by logistic/Cox regression using the area under the ROC curve (AUC). The Ssurf localization and prediction capability were compared to (1) the Svol obtained by DVM analysis in the same cohort and (2) the Ssurf obtained from other DSM studies. Results Three Ssurf were identified in the bladder: posterior for acute retention (AUC = 0.64), posterior–superior for late retention (AUC = 0.68), and inferior–anterior–lateral for late dysuria (AUC = 0.73). Five Svol were identified: one in the urethra for acute incontinence and four in the posterior bladder part for acute and late retention, late dysuria, and hematuria. The overlap between Ssurf and Svol was moderate for acute retention, good for late retention, and bad for late dysuria, and AUCs ranged from 0.62 to 0.81. The prediction capabilities of Ssurf and Svol models were not significantly different. Among five symptoms comparable between cohorts, common Ssurf was found only for late dysuria, with a good spatial agreement. Conclusion Spatial agreement between methods is relatively good although DVM identified more sub-regions. Reproducibility of identified Ssurf between cohorts is low.
#1Eugenia Mylona(French Institute of Health and Medical Research)H-Index: 4
#2Oscar Acosta(French Institute of Health and Medical Research)H-Index: 21
Last. Renaud de Crevoisier(French Institute of Health and Medical Research)H-Index: 28
view all 12 authors...
Purpose To apply a voxel-based analysis to identify urethrovesical symptom-related subregions (SRSs) associated with acute and late urinary toxicity in prostate cancer radiation therapy. Methods and Materials Two hundred seventy-two patients with prostate cancer treated with intensity-modulated radiation therapy/image-guided radiation therapy were analyzed prospectively. Each patient's computed tomography imaging was spatially normalized to a common coordinate system via nonrigid registration. T...
#1Frederik Fuchs(TUM: Technische Universität München)H-Index: 1
#2Gregor Habl(TUM: Technische Universität München)H-Index: 21
Last. Kerstin A. Kessel(TUM: Technische Universität München)H-Index: 20
view all 6 authors...
PURPOSE: The aim of this study was to identify volume changes and dose variations of rectum and bladder during radiation therapy in prostate cancer (PC) patients. MATERIALS AND METHODS: We analyzed 20 patients with PC treated with helical tomotherapy. Daily image guidance was performed. We re-contoured the entire bladder and rectum including its contents as well as the organ walls on megavoltage computed tomography once a week. Dose variations were analyzed by means of Dmedian, Dmean, Dmax, V10 ...
Purpose The optimal frequency of prostate cancer image guided radiation therapy (IGRT) has not yet been clearly identified. This study sought to compare the safety and efficacy of daily versus weekly IGRT. Materials and Methods This phase 3 randomized trial recruited patients with N0 localized prostate cancer. The total IGRT doses in the prostate ranged from 70 Gy to 80 Gy, sparing the lymph nodes. Patients were randomly assigned (1:1) to 2 prostate IGRT frequency groups: daily and weekly (ie, o...
BACKGROUND AND PURPOSE: Incontinence, hematuria, voiding frequency and pain during voiding are possible side effects of radiotherapy among patients treated for prostate cancer. The objective of this study was to develop multivariable NTCP models for these side effects. MATERIAL AND METHODS: This prospective cohort study was composed of 243 patients with localized or locally advanced prostate cancer (stage T1-3). Genito-urinary (GU) toxicity was assessed using a standardized follow-up program. Th...
Background and purpose Segmentation of intra-prostatic urethra for dose assessment from planning CT may help explaining urinary toxicity in prostate cancer radiotherapy. This work sought to: i) propose an automatic method for urethra segmentation in CT, ii) compare it with previously proposed surrogate models and iii) quantify the dose received by the urethra in patients treated with IMRT. Materials and methods A weighted multi-atlas-based urethra segmentation method was devised from a training ...
Advances in radiotherapy (RT) have allowed an increased proportion of lung cancer patients to be treated curatively. High doses delivered to critical thoracic organs can result in excess mortality with tolerance doses poorly defined. This work presents a novel method of identifying anatomical dose-sensitive regions within the thorax. A high-resolution, normal-tissue dosimetric analysis was performed to identify regions in the heart that correlate with poorer survival. A total of 1101 patients tr...
Abstract Background and purpose Urinary incontinence following radiotherapy (RT) for prostate cancer (PCa) has a relevant impact on patient’s quality of life. The aim of the study was to assess the unknown dose–effect relationship for late patient-reported urinary incontinence (LPRUI). Methods and materials Patients were enrolled within the multi-centric study DUE01. Clinical and dosimetry data including the prescribed 2 Gy equivalent dose (EQD2) were prospectively collected. LPRUI was evaluated...
Last. Laura Cella(National Research Council)H-Index: 24
view all 10 authors...
The risk of radiation-induced toxicity in patients treated for head and neck (HN) cancer with radiation therapy (RT) is traditionally estimated by condensing the 3D dose distribution into a monodimensional cumulative dose-volume histogram which disregards information on dose localization. We hypothesized that a voxel-based approach would identify correlations between radiation-induced morbidity and local dose release, thus providing a new insight into spatial signature of radiation sensitivity i...
To report grade ≥2 overall late rectal and urinary toxicities in patients (pts) with prostate cancer treated by intensity-modulated radiotherapy (IMRT) at 3 dose-levels. Identify predictors of radiation toxicity and report biochemical progression free survival (bPFS). A total of 277 pts were treated with 70Gy (10.8%), 74Gy (63.9%) and 80 Gy (25.3%) using IMRT without pelvic irradiation were analyzed. Short or long-course androgen deprivation therapy (ADT) was allowed in 46.1% of pts. The toxicit...
#1Eugenia Mylona(French Institute of Health and Medical Research)H-Index: 4
#2Martin A. Ebert(UWA: University of Western Australia)H-Index: 26
Last. Renaud de Crevoisier(French Institute of Health and Medical Research)H-Index: 28
view all 9 authors...
Abstract Purpose /Objectives: Recent voxel-based studies have shown that the dose to specific rectal and urethro-vesical subregions is predictive of toxicities, following prostate cancer IMRT. The objective of this study was to validate the discriminatory power of these subregions with respect to the whole organs, in a large independent population. Material/Methods The validation cohort consisted of 450 patients, from the XXX(BLIND) trial, treated with 3D-CRT at 66-74 Gy. Previous voxel-based an...
Abstract Background and purpose Normal tissue complication probability (NTCP) models applied for model-based patient selection to proton therapy (PT) have usually been derived using dose/volume histogram (DVH) parameters from photon-based radiotherapy. This study aimed to derive PT-specific multivariate NTCP models that also accounted for the spatial dose distribution (rectum only) as well as non-dose/volume related factors. Materials and methods The study included rectum and bladder DVHs, 2D re...
Last. Oscar Acosta(University of Rennes)H-Index: 21
view all 6 authors...
Prediction of urinary toxicity after prostate cancer radiotherapy (RT) is remarkably challenging. Not only it is a multifaceted phenomenon, encompassing different symptoms (retention, dysuria, haematuria, etc.), but also a multifactorial problem, as it depends on both patient-specific clinical factors, individual biological parameters, and dosimetric patterns. Thus, there are a plethora of potential predictors compared to the paucity of available symptom-specific toxicity data. On top of that, i...
#1Caroline Lafond(French Institute of Health and Medical Research)H-Index: 15
#2A. Barateau(French Institute of Health and Medical Research)H-Index: 5
Last. Renaud de Crevoisier(French Institute of Health and Medical Research)H-Index: 28
view all 10 authors...
Background: A rectal sub-region (SRR) has been previously identified by voxel-wise analysis in the inferior-anterior part of the rectum as highly predictive of rectal bleeding (RB) in prostate cancer radiotherapy. Translating the SRR to patient-specific radiotherapy planning is challenging as new constraints have to be defined. A recent geometry-based model proposed to optimize the planning by determining the achievable mean doses (AMDs) to the organs at risk (OARs), taking into account the over...