***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: PURPOSE To investigate the set-up errors and deformation associated with daily placement of endorectal balloons in prostate radiotherapy .  MATERIAL S AND METHODS Endorectal balloons were placed daily in 20 prostate cancer patients undergoing radiotherapy . Electronic portal images ( EPIs ) were collected weekly from anterior-posterior ( AP ) and lateral views . The EPIs were compared with digitally reconstructed radiographs from computed tomography scans obtained during pretreatment period to estimate displacements . The interfraction deformation of balloon was estimated with variations in diameter in three orthogonal directions throughout the treatment course . RESULTS A total of 154 EPIs were evaluated . The mean displacements of balloon relative to bony l and mark were 1.8 mm in superior-inferior ( SI ) , 1.3 mm in AP , and 0.1 mm in left-right ( LR ) directions . The systematic errors in SI , AP , and LR directions were 3.3 mm , 4.9 mm , and 4.0 mm , respectively . The r and om ( interfraction ) displacements , relative to either bony l and marks or treatment isocenter , were larger in SI direction ( 4.5 mm and 4.5 mm ) , than in AP ( 3.9 mm and 4.4 mm ) and LR directions ( 3.0 mm and 3.0 mm ) . The r and om errors of treatment isocenter to bony l and mark were 2.3 mm , 3.2 mm , and 2.6 mm in SI , AP , and LR directions , respectively . Over the treatment course , balloon deformations of 2.8 mm , 2.5 mm , and 2.6 mm occurred in SI , AP , and LR directions , respectively . The coefficient of variance of deformation was 7.9 % , 4.9 % , and 4.9 % in these directions . CONCLUSIONS Larger interfractional displacement and the most prominent interfractional deformation of endorectal balloon were both in SI direction PURPOSE To evaluate the Vienna  Rectoscopy Score ( VRS ) as a feasible and effective tool for detecting and classifying pathologic changes in the rectal mucosa after radiotherapy ( RT ) for prostate cancer , and , also , to correlate its findings with the European Organization for Research and Treatment of Cancer (EORTC)/Radiation Therapy Oncology Group ( RTOG ) score for late rectal toxicity . METHODS AND MATERIAL S A total of 486 patients with localized prostate cancer underwent external-beam RT up to 70 or 74 Gy within an Austrian-German prospect i ve multicenter trial . In 166 patients , voluntary rectal sigmoidoscopy was performed before and at 12 and /or 24 months after RT .  Pathologic findings such as telangiectasia , congested mucosa , and ulcers were grade d ( Grade s 0 - 3 ) and summarized according to the VRS . Late rectal side effects ( EORTC/RTOG ) were documented and correlated with the corresponding VRS . RESULTS Before RT , 99 % had a VRS score of 0 . The median follow-up was 40 months . Overall , a late rectal side effects grade or score 1 - 3 was detected in 43 % by EORTC/RTOG compared with 68 % by VRS ( p < 0.05 ) . Grade s 0 , 1 , 2 , and 3 late rectal side effects were found using EORTC/RTOG in 57 % , 11 % , 28 % , and 3 % , respectively ; the corresponding percentages were 32 % , 22 % , 32 % , and 14 % for a VRS of 0 , 1 , 2 , and 3 , respectively . A significant coherence between the VRS and EORTC/RTOG was found ( p < 0.01 ) . CONCLUSIONS The VRS is a feasible and effective tool for describing and classifying pathologic findings in the rectal mucosa after RT within a multicenter trial . The VRS and EORTC/RTOG showed a high coherence . However the VRS was significantly more sensitive A  prostate treatment immobilization system  was evaluated with respect to setup errors and efficiency for a specific treatment setup . Prostate patients were treated in the prone position with a rectal catheter  using the NOMOS intensity modulated radiotherapy system .  Immobilization and setup consisted of a Vac‐Lok ™ bag ( MED‐TEC , Orange City , IO ) fitted within a registration carrier box where patients were aligned to the bag using skin marks along the lower leg . Daily setup errors were analyzed using lateral portal films , registration plates mounted to the carrier box , and the pubic symphasis as a bony reference . Two studies were conducted to evaluate setup technique . In the first study , patient setup required 3–5 minutes for patient positioning and the corresponding superior/inferior errors were found to have a st and ard deviation of 3.5 mm . In the second study , the technique st and ards were reduced to allow for faster setup times and , consequently , larger errors ; setup times were 1–2 minutes and the mean and st and ard deviation errors were ~2 and 5 mm , respectively . PACS number(s ) : 87.53.–j , PURPOSE When > 25 % of the rectum is irradiated to > or = 70 Gy , the risk of developing Grade 2 or higher rectal complications is significantly increased . This study evaluates the impact on dose to the rectum from the use of an intrarectal ( IR ) balloon device , previously shown to immobilize the prostate gl and and localize the rectum , in patients receiving dose escalated 3-dimentional ( 3D ) conformal radiation therapy . MATERIAL S AND METHODS From July 2001 through February 2003 , 28 consecutive patients with prostate cancer underwent computerized tomography-based simulation with and without the IR balloon in place . Treatment planning was performed for three clinical paradigms in which the IR balloon was not used at all ( 0 Gy ) , used during the cone-down for 15 treatments ( 28.35 Gy ) , or used for the entire course of 40 treatments ( 75.6 Gy ) . The three plans were compared for differences in the percent of rectum receiving > 70 Gy . RESULTS Dose volume histogram ( DVH ) analysis revealed that the median(range ) of percent rectal volume exceeding 70 Gy was 25 % ( 12.7 - 41.5 % ) , 7.5 % ( 0.9 - 19.5 % ) , and 3.6 % ( 0 - 8.7 % ) for patients in whom the IR balloon was used for 0 , 15 , and 40 treatments , respectively . The percent of rectum exceeding 70 Gy was significantly different for all treatment plan comparisons ( P < 0.0001 ) . CONCLUSIONS Grade 2 or higher rectal toxicity may be minimized during dose escalated 3D conformal radiation therapy through the use of an IR balloon during the 3-week cone down portion of an 8-week treatment course Purpose : Evaluation of late side effects and biochemical control ( bNED ) 5 years after three-dimensional radiotherapy with moderate , risk-adapted dose escalation . Patients and Methods : From 03/1999 to 07/2002 , 486 patients have been registered in the prospect i ve Austrian-German multicenter phase II trial ( AUGE ) . 399 ( 82 % ) localized prostate cancer patients ( T1–3 Nx/N0 M0 ) were evaluated . The low- and intermediate-risk groups were treated with 70 Gy , the high-risk group with 74 Gy , respectively . Additional hormonal therapy ( HT ) was recommended for intermediate- and high-risk group patients . Late toxicity ( EORTC/RTOG ) and bNED ( ASTRO and Phoenix ) were prospect ively assessed . Results : Median follow-up was 65 months . Distribution concerning risk groups ( low- , intermediate- , high-risk group ) showed 29 % , 50 % and 21 % of patients , respectively . HT was given in 87 % of patients . The 5-year actuarial rates of late side effects grade ≥ 2 for 70 Gy/74 Gy were 28%/30 % ( gastrointestinal ; p = 0.73 ) and 19%/34 % ( urogenital ; p = 0,06 ) . The 5-year actuarial bNED rate stratified by risk groups ( low- , intermediate- , high-risk group ) was 74 % , 66 % and 50 % ( ASTRO ) , and 81 % , 80 % and 60 % ( Phoenix ) , respectively . Within multivariate analysis T-stage and initial prostate specific antigen were significant factors influencing bNED ( ASTRO ) whereas Gleason Score and duration of HT were not . Conclusion : Dose escalation within st and ard three-dimensional conformal radiotherapy ( 3D-CRT ) up to a level of 74 Gy did not result in significantly increased gastrointestinal side effects , whereas urogenital side effects showed an increase close to significance . However , the total number of patients with severe toxicity was low . To achieve high tumor control rates with acceptable treatment-related morbidity , local doses of at least 74 Gy should be considered , in particular for intermediate- or high-risk patients  applying 3D-CRT.Ziel : Bestimmung von Spätnebenwirkungen und biochemischer Kontrolle ( bNED ) nach risikoadaptierter Dosiseskalation i m Rahmen einer prospektiven österreichisch-deutschen Phase-II-Multicenterstudie . Patienten und Method ik : Von 03/1999 bis 07/2002 wurden 486 Patienten mit Prostatakarzinom ( T1–3 Nx/N0 M0 ) gemeldet , und 399 ( 82 % ) kamen zur Auswertung . Patienten der Niedrig- und Intermediärrisikogruppe wurden mit 70 Gy , die Hochrisikogruppe mit 74 Gy bestrahlt ( Tabelle 1 ) . Eine begleitende Hormontherapie wurde für Patienten der Intermediär- und Hochrisikogruppe empfohlen . Spätnebenwirkungen ( EORTC/RTOG ) und bNED ( ASTRO/Phoenix ) wurden ermittelt . Ergebnisse : Der mittlere Nachbeobachtungszeitraum betrug 65 Monate . Hinsichtlich der Risikogruppen ( Niedrig- , Intermediär- , Hochrisikogruppe ) f and en sich 29 % , 50 % , und 21 % Patienten . Eine begleitende  Hormontherapie  erhielten 87 % der Patienten . Detaillierte Patienten date n sind in Tabelle 2 aufgeführt . Die 5-Jahres-Raten an Spätnebenwirkungen Grad ≥ 2 für 70 Gy/74 Gy lagen bei 28%/30 % ( gastrointestinal ; p = 0,73 ) und 19%/34 % ( urogenital ; p = 0,06 ; Abbildungen 1 und 2 ) . Die 5-Jahres-bNED-Raten entsprechend den Risikogruppen ( Niedrig- , Intermediär- , Hochrisikogruppe ) lagen bei 74 % , 66 % und 50 % ( ASTRO ; Abbildung 3 ) bzw . 81 % , 80 % und 60 % ( Phoenix ; Abbildung 4 ) . In der multivariaten Analyse zeigten sich T-Stadium und initiales prostataspezifisches Antigen als signifikant bezüglich bNED ( ASTRO ) und Gleason-Score sowie die Dauer der Hormontherapie als nicht signifikant ( Tabelle 4).Schlussfolgerung : Die Dosissteigerung auf 74 Gy führt zu keinen signifikant erhöhten Raten an gastrointestinalen Spätnebenwirkungen . Die Rate an urogenitalen Spätnebenwirkungen ist hingegen erhöht . Insgesamt finden sich jedoch nur wenige schwere Grad-3-Spätnebenwirkungen ( Tabelle 3 ) . Um respektable Tumorkontrollraten ( Abbildung 5 ) zu erreichen , sollte , vor allem für Patienten der Intermediär- und Hochrisikogruppe , eine lokale Dosis von zumindest 74 Gy appliziert werden PURPOSE To assess the benefit of escalating the dose in definitive prostate cancer radiotherapy vs. the associated risk of complications . MATERIAL S AND METHODS Between 1987 and 1999 , 1087 patients with clinical Stage T1b-T3 adenocarcinoma of the prostate were definitively irradiated without hormonal therapy and had a pretreatment serum prostate-specific antigen ( PSA ) and Gleason score recorded . The median follow-up was 65 months . Doses ranged from 64 to 78 Gy , with the treatment techniques corresponding to the year of therapy and the prescribed dose . A total of 301 patients were treated on a r and omized protocol to either 70 or 78 Gy .  Also , 163 patients were treated with three-dimensional conformal therapy and had dose-volume histograms available for review . RESULTS Tumor stage , grade , pretreatment PSA level , and radiation dose were all independent predictors of PSA disease-free survival ( PSA-DFS ) in multivariate analysis . The hazard rate for biochemical failure peaked at 1.5 - 3 years after radiotherapy . Although a statistically significant dose effect on PSA-DFS was found in the pretreatment PSA levels of those with both < or = 10 ng/mL 
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RESULTS Overall , ERBs are tolerated well , although patients with pre-existing anorectal disease have an increased risk of developing ERB-related toxicity .
Planning studies show reduced Rwall and anal wall ( Awall ) doses with ERB application .
ERBs seem well-tolerated and in planning studies reduce anorectal wall doses .