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1.
Radiother Oncol ; 140: 131-142, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31276989

RESUMO

Stereotactic body radiotherapy (SBRT) for prostate cancer (PCa) is gaining interest by the recent publication of the first phase III trials on prostate SBRT and the promising results of many other phase II trials. Before long term results became available, the major concern for implementing SBRT in PCa in daily clinical practice was the potential risk of late genitourinary (GU) and gastrointestinal (GI) toxicity. A number of recently published trials, including late outcome and toxicity data, contributed to the growing evidence for implementation of SBRT for PCa in daily clinical practice. However, there exists substantial variability in delivering SBRT for PCa. The aim of this topical review is to present a number of prospective trials and retrospective analyses of SBRT in the treatment of PCa. We focus on the treatment strategies and techniques used in these trials. In addition, recent literature on a simultaneous integrated boost to the tumor lesion, which could create an additional value in the SBRT treatment of PCa, was described. Furthermore, we discuss the multicenter consensus of the FLAME consortium on SBRT for PCa with a focal boost to the macroscopic intraprostatic tumor nodule(s).


Assuntos
Neoplasias da Próstata/radioterapia , Radiocirurgia/métodos , Consenso , Humanos , Masculino , Estudos Prospectivos , Dosagem Radioterapêutica , Estudos Retrospectivos
2.
Acta Oncol ; 58(1): 57-65, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30474448

RESUMO

BACKGROUND AND PURPOSE: Patients with low-grade glioma (LGG) have a prolonged survival expectancy due to better discriminative tumor classification and multimodal treatment. Consequently, long-term treatment toxicity gains importance. Contemporary radiotherapy techniques such as intensity-modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT), tomotherapy (TOMO) and intensity-modulated proton therapy (IMPT) enable high-dose irradiation of the target but they differ regarding delivered dose to organs at risk (OARs). The aim of this comparative in silico study was to determine these dosimetric differences in delivered doses. MATERIAL AND METHODS: Imaging datasets of 25 LGG patients having undergone postoperative radiotherapy were included. For each of these patients, in silico treatment plans to a total dose of 50.4 Gy to the target volume were generated for the four treatment modalities investigated (i.e., IMRT, VMAT, TOMO, IMPT). Resulting treatment plans were analyzed regarding dose to target and surrounding OARs comparing IMRT, TOMO and IMPT to VMAT. RESULTS: In total, 100 treatment plans (four per patient) were analyzed. Compared to VMAT, the IMPT mean dose (Dmean) for nine out of 10 (90%) OARs was statistically significantly (p < .02) reduced, for TOMO this was true in 3/10 (30%) patients and for 1/10 (10%) patients for IMRT. IMPT was the prime modality reducing dose to the OARs followed by TOMO. DISCUSSION: The low dose volume to the majority of OARs was significantly reduced when using IMPT compared to VMAT. Whether this will lead to a significant reduction in neurocognitive decline and improved quality of life is to be determined in carefully designed future clinical trials.


Assuntos
Neoplasias Encefálicas/radioterapia , Glioma/radioterapia , Órgãos em Risco/efeitos da radiação , Terapia com Prótons/métodos , Humanos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada
4.
Radiother Oncol ; 127(1): 74-80, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29336835

RESUMO

PURPOSE: To compare toxicity rates in patients with localized prostate cancer treated with standard fractionated external beam radiotherapy (EBRT) with or without an additional integrated boost to the macroscopically visible tumour. MATERIAL AND METHODS: FLAME is a phase 3 multicentre RCT (NCT01168479) of patients with pathologically confirmed localized intermediate or high-risk prostate cancer. The standard treatment arm (n = 287) received a dose to the entire prostate of 77 Gy in 35 fractions. The dose-escalated treatment arm (n = 284) received 77 Gy in 35 fractions to the entire prostate, with an integrated boost up to 95 Gy to the multi-parametric MRI-defined (macroscopic) tumour within the prostate. Treatment related toxicity was measured using the CTCAE version 3.0. Grade 2 or worse GU or GI events up to two years were compared between groups by presenting proportions and by Generalized Estimating Equations (GEE) analyses for repeated measures. RESULTS: Ninety percent of the 571 men randomly assigned between September 2009 and January 2015 had high-risk disease (Ash 2000), of whom nearly 66% were prescribed hormonal therapy up to three years. Median follow-up was 55 months at the time of this analysis. Toxicity prevalence rates for both GI and GU increased until the end of treatment and regressed thereafter, with no obvious differences across treatment groups. Late cumulative GI toxicity rates were 11.1% and 10.2% for the standard and dose-escalated group, respectively. These rates were 22.6% and 27.1% for GU toxicity. GEE analyses showed that both GU toxicity and GI toxicity (≥grade 2) up to two years after treatment were similar between arms (OR 1.02 95%CI 0.78-1.33p = 0.81 and (OR 1.19 95%CI 0.82-1.73p = 0.38), respectively. CONCLUSIONS: In intermediate- and high-risk prostate cancer patients, focal dose escalation integrated with standard EBRT did not result in an increase in GU and GI toxicity when compared to the standard treatment up to two years after treatment. This suggests that the described focal dose escalation technique is safe and feasible.


Assuntos
Neoplasias da Próstata/radioterapia , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/efeitos adversos , Braquiterapia/métodos , Protocolos Clínicos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/patologia , Hipofracionamento da Dose de Radiação , Lesões por Radiação/etiologia , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Método Simples-Cego
5.
Int J Radiat Oncol Biol Phys ; 99(5): 1243-1252, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-28943074

RESUMO

PURPOSE: The phase 3 HYpofractionated irradiation for PROstate cancer (HYPRO) trial randomized patients with intermediate- to high-risk localized prostate cancer to conventionally fractionated (78 Gy in 39 fractions) or hypofractionated (64.6 Gy in 19 fractions) radiation therapy. Differences in techniques and treatment protocols were present between participating centers. This study aimed to compare dose parameters and patient-reported gastrointestinal symptoms between these centers. METHODS AND MATERIALS: From the trial population, we selected patients (N=572) from 4 treatment centers who received image guided (IG) intensity modulated radiation therapy (IMRT). Center A (n=242) applied planning target volume (PTV) margins of 5 to 6 mm and was considered the reference center. In center B (n=170, 7-mm margins), magnetic resonance imaging (MRI) was integrated in treatment planning. An endorectal balloon (ERB) was applied in center C (n=85, 7-mm margins). Center D (n=75) applied the largest PTV margins of 8 mm. The study protocol provided identical anorectal dose constraints, and local protocols were applied for further treatment optimization. Anorectal dose-surface histograms were compared by applying t tests. Rectal complaints during follow-up (6 months to 4 years) were compared in a generalized linear model, adjusting for age, follow-up, treatment arm, and hormone therapy. RESULTS: Favorable anorectal dose distributions were found for center B (MRI delineation) and center C (ERB application) as compared with centers A and D. These were associated with significantly lower incidences of patient-reported complaints of rectal incontinence, use of incontinence pads, and rectal discomfort in these centers. Furthermore, lower incidences of increased stool frequency (≥4 per day) and mucous loss were observed for center C. CONCLUSIONS: Despite comparable IG-IMRT techniques and predefined dose constraints, pronounced differences in dose distributions and toxicity rates were observed. MRI delineation and ERB application were associated with favorable rectal dose parameters and toxicity profiles, whereas a 2- to 3-mm difference in PTV margins did not translate into observed differences. We conclude that choices for treatment optimization of IG-IMRT are important and clinically relevant for patients since these affect symptoms experienced in daily life.


Assuntos
Canal Anal/efeitos da radiação , Neoplasias da Próstata/radioterapia , Lesões por Radiação/prevenção & controle , Radioterapia Guiada por Imagem/métodos , Radioterapia de Intensidade Modulada/métodos , Reto/efeitos da radiação , Adulto , Idoso , Idoso de 80 Anos ou mais , Institutos de Câncer , Protocolos Clínicos , Incontinência Fecal/prevenção & controle , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Países Baixos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Hipofracionamento da Dose de Radiação , Radioterapia Guiada por Imagem/efeitos adversos , Radioterapia Guiada por Imagem/instrumentação , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/instrumentação , Tomografia Computadorizada por Raios X
6.
Prostate ; 77(10): 1160-1166, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28594087

RESUMO

INTRODUCTION: Adult prostatic sarcoma (PS) is a rare disease. While surgery is considered the standard approach, the role of other therapies is not completely established. We report results of the largest multicentric contemporary cohort of PS patients. MATERIALS AND METHODS: This study included 61 adult PS patients treated in 16 American and European Institutions. Median age was 64.4 years (range: 22-87). Curative surgery was delivered in 48 patients (prostatectomy = 26, cystoprostatectomy = 22), usually with lymphadenectomy (n = 40). Curative radiotherapy (RT) was delivered in 32 patients, as radical (n = 5), neoadjuvant (n = 10), or postoperative treatment (n = 17). Eighteen patients received chemotherapy. None of the patients received hormonal therapy. RESULTS: Median follow-up was 72 months (95%CI: 55-not reached). Five-year local control (LC), overall survival (OS), cancer-specific survival, disease-free survival, and metastases-free rates were 47%, 53%, 56%, 35%, and 35%, respectively. Notably, curative RT (neoadjuvant, adjuvant, or definitive) was associated with improved 5-year LC (55% vs. 31%, P = 0.02) and OS (59% vs. 46%, P = 0.1). Surgically treated patients presenting with a cT3-4 tumor (n = 31), who received RT (n = 24), had a significantly improved 5-year LC (68% vs, 33%, P = 0.004) and OS (65% vs. 21%, P < 0.001) rates compared to patients not receiving RT. cT4 patients demonstrated a significantly lower 5-year OS (43% vs. 61%, P = 0.006) and LC (29% vs. 69%, P < 0.001) rates. Histologic subtype was not associated with LC and OS, but patients with prostatic stromal sarcoma, rhabdomyosarcoma, or sarcomatoid carcinoma had worse 5-year LC compared to other types (47% vs. 55%) and OS (49% vs. 58%). CONCLUSION: Adult PS has a poor prognosis. Locally advanced tumors have poor LC and OS rates. Curative RT should be considered part of the multidisciplinary approach to PS.


Assuntos
Antineoplásicos/uso terapêutico , Excisão de Linfonodo , Prostatectomia , Neoplasias da Próstata , Radioterapia , Sarcoma , Adulto , Idoso , Terapia Combinada/métodos , Terapia Combinada/estatística & dados numéricos , Humanos , Cooperação Internacional , Excisão de Linfonodo/métodos , Excisão de Linfonodo/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Próstata/patologia , Prostatectomia/métodos , Prostatectomia/estatística & dados numéricos , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Radioterapia/métodos , Radioterapia/estatística & dados numéricos , Doenças Raras/mortalidade , Doenças Raras/patologia , Doenças Raras/terapia , Sarcoma/mortalidade , Sarcoma/patologia , Sarcoma/terapia , Análise de Sobrevida
7.
Curr Urol Rep ; 15(3): 389, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24430170

RESUMO

Nodal staging in prostate cancer is suboptimal both with respect to current imaging modalities and pelvic lymph node dissection, and thus other techniques are being explored. Lymphotropic nanoparticle-enhanced MRI, also called magnetic resonance lymphography (MRL), is a technique that has shown high sensitivity (65-92 %) and excellent specificity (93-98 %) in detecting prostate cancer lymph node metastases. This technique aids in the detection of metastases in non-enlarged small nodes. MRL has been useful in determining the location and pathways of spread in nodal chains. Knowledge of the location of lymph node involvement is important for decisions regarding appropriate therapeutic options, such as image-guided therapy.. A geographic miss in radiotherapy can be avoided with the use of MRL-guided focal therapy. This paper provides an overview of current literature, lessons learned, and new therapeutic options with nanoparticle-enhanced MRI.


Assuntos
Meios de Contraste , Dextranos , Imagem por Ressonância Magnética/métodos , Nanopartículas de Magnetita , Neoplasias da Próstata/diagnóstico , Humanos , Excisão de Linfonodo , Irradiação Linfática/métodos , Metástase Linfática , Linfografia/métodos , Masculino , Estadiamento de Neoplasias , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Radioterapia Guiada por Imagem/métodos , Sensibilidade e Especificidade
8.
Int J Colorectal Dis ; 29(3): 273-83, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24150230

RESUMO

PURPOSE: Pelvic radiotherapy may lead to changes of anorectal function resulting in incontinence-related complaints. The aim of this study was to systematically review objective findings of late anorectal physiology and mucosal appearance after irradiation for prostate cancer. METHODS: MEDLINE, EMBASE, and the Cochrane library were searched. Original articles in which anal function, rectal function, or rectal mucosa were examined ≥3 months after EBRT for prostate cancer were included. RESULTS: Twenty-one studies were included with low to moderate quality. Anal resting pressures significantly decreased in 6 of the 9 studies including 277 patients. Changes of squeeze pressure and rectoanal inhibitory reflex were less uniform. Rectal distensibility was significantly impaired after EBRT in 7 of 9 studies (277 patients). In 4 of 9 studies on anal and in 5 of 9 on rectal function, disturbances were associated with urgency, frequent bowel movements or fecal incontinence. Mucosal changes as assessed by the Vienna Rectoscopy Score revealed telangiectasias in 73 %, congestion in 33 %, and ulceration in 4 % of patients in 8 studies including 346 patients, but no strictures or necrosis. Three studies reported mucosal improvement during follow-up. Telangiectasias, particularly multiple, were associated with rectal bleeding. Not all bowel complaints (30 %) were related to radiotherapy. CONCLUSIONS: Low to moderate quality evidence indicates that EBRT reduces anal resting pressure, decreases rectal distensibility, and frequently induces telangiectasias of rectal mucosa. Objective changes may be associated with fecal incontinence, urgency, frequent bowel movements, and rectal bleeding, but these symptoms are not always related to radiation damage.


Assuntos
Canal Anal/fisiopatologia , Canal Anal/efeitos da radiação , Neoplasias da Próstata/radioterapia , Reto/fisiopatologia , Reto/efeitos da radiação , Defecação/efeitos da radiação , Incontinência Fecal/etiologia , Humanos , Mucosa Intestinal/patologia , Mucosa Intestinal/efeitos da radiação , Masculino , Pressão , Radioterapia/efeitos adversos , Telangiectasia/etiologia , Úlcera/etiologia
10.
Int J Colorectal Dis ; 28(4): 519-26, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23080344

RESUMO

PURPOSE: Anorectal dysfunction is common after pelvic radiotherapy. This study aims to explore the relationship of subjective and objective anorectal function with quality of life (QoL) and their relative impact in patients irradiated for prostate cancer. METHODS: Patients underwent anal manometry, rectal barostat measurement, and completed validated questionnaires, at least 1 year after prostate radiotherapy (range 1-7 years). QoL was measured by the Fecal Incontinence Quality of Life scale (FIQL) and the Expanded Prostate Cancer Index Composite Bowel domain (EPICB)-bother subscale. Severity of symptoms was rated by the EPICB function subscale. RESULTS: Anorectal function was evaluated in 85 men. Sixty-three percent suffered from one or more anorectal symptoms. Correlations of individual symptoms ranged from r = 0.23 to r = 0.53 with FIQL domains and from r = 0.36 to r = 0.73 with EPICB bother scores. They were strongest for fecal incontinence and urgency. Correlations of anal sphincter pressures, rectal capacity, and sensory thresholds ranged from r = 0.00 to r = 0.42 with FIQL domains and from r = 0.15 to r = 0.31 with EPICB bother scores. Anal resting pressure correlated most strongly. Standardized regression coefficients for QoL outcomes were largest for incontinence, urgency, and anal resting pressure. Regression models with subjective parameters explained a larger amount (range 26-92 %) of variation in QoL outcome than objective parameters (range 10-22 %). CONCLUSIONS: Fecal incontinence and rectal urgency are the symptoms with the largest influence on QoL. Impaired anal resting pressure is the objective function parameter with the largest influence. Therefore, sparing the structures responsible for an adequate fecal continence is important in radiotherapy planning.


Assuntos
Canal Anal/fisiopatologia , Pelve/fisiopatologia , Pelve/efeitos da radiação , Neoplasias da Próstata/radioterapia , Qualidade de Vida , Reto/fisiopatologia , Idoso , Humanos , Masculino , Análise de Regressão , Inquéritos e Questionários
11.
Europace ; 15(1): 60-5, 2013 01.
Artigo em Inglês | MEDLINE | ID: mdl-22848077

RESUMO

AIMS: To investigate the behaviour of the implantable cardioverter defibrillator (ICD) function during actual radiotherapy sessions. METHODS AND RESULTS: Fifteen patients with an ICD underwent 17 radiation treatments for cancer [cumulative dose to the tumour was between 16 Gray (Gy) and 70 Gy; photon beams with maximum energies between 6 megaelectronvolt (MeV) and 18 MeV were employed]. During every session, the ICD was programmed to a monitoring mode to prevent inappropriate therapy delivery. Afterwards, the ICDs were interrogated to ensure proper function. Calculated radiation dose at the ICD site was <1 Gy in all patients. In 5 out of 17 radiation treatments (29%) the ICDs showed 6 malfunctions (35%). We noticed four disturbances in the memory data or device resets during radiation treatment and one case of inappropriate ventricular fibrillation detection due to external noise. In one case a late device data error was observed. All malfunctions occurred at 10 and 18 MeV beam energies. CONCLUSION: Despite the fact that all recommended precautions were taken to minimize the damage to the ICDs during radiotherapy and the calculated dose to the ICDs was <1 Gy, in 29% of the treatments a malfunction occurred. We observed a possible correlation between the beam energy and the malfunctions. This correlation may be due to an interaction between neutrons produced in the head of the linear accelerator at beam energies ≥10 MeV, and boron-10 which is present in the integrated circuit.


Assuntos
Desfibriladores Implantáveis/estatística & dados numéricos , Análise de Falha de Equipamento/estatística & dados numéricos , Falha de Equipamento/estatística & dados numéricos , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/prevenção & controle , Radioterapia Conformacional/estatística & dados numéricos , Idoso , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Países Baixos , Nêutrons , Doses de Radiação , Fatores de Risco
12.
Int J Radiat Oncol Biol Phys ; 83(2): 636-44, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22137024

RESUMO

PURPOSE: To delineate the individual pelvic floor muscles considered to be involved in anorectal toxicity and to investigate dose-effect relationships for fecal incontinence-related complaints after prostate radiotherapy (RT). METHODS AND MATERIALS: In 48 patients treated for localized prostate cancer, the internal anal sphincter (IAS) muscle, the external anal sphincter (EAS) muscle, the puborectalis muscle (PRM), and the levator ani muscles (LAM) in addition to the anal wall (Awall) and rectal wall (Rwall) were retrospectively delineated on planning computed tomography scans. Dose parameters were obtained and compared between patients with and without fecal urgency, incontinence, and frequency. Dose-effect curves were constructed. Finally, the effect of an endorectal balloon, which was applied in 28 patients, was investigated. RESULTS: The total volume of the pelvic floor muscles together was about three times that of the Awall. The PRM was exposed to the highest RT dose, whereas the EAS received the lowest dose. Several anal and rectal dose parameters, as well as doses to all separate pelvic floor muscles, were associated with urgency, while incontinence was associated mainly with doses to the EAS and PRM. Based on the dose-effect curves, the following constraints regarding mean doses could be deduced to reduce the risk of urgency: ≤ 30 Gy to the IAS; ≤ 10 Gy to the EAS; ≤ 50 Gy to the PRM; and ≤ 40 Gy to the LAM. No dose-effect relationships for frequency were observed. Patients treated with an endorectal balloon reported significantly less urgency and incontinence, while their treatment plans showed significantly lower doses to the Awall, Rwall, and all pelvic floor muscles. CONCLUSIONS: Incontinence-related complaints show specific dose-effect relationships to individual pelvic floor muscles. Dose constraints for each muscle can be identified for RT planning. When only the Awall is delineated, substantial components of the continence apparatus are excluded.


Assuntos
Canal Anal/efeitos da radiação , Incontinência Fecal/etiologia , Músculos/efeitos da radiação , Neoplasias da Próstata/radioterapia , Reto/efeitos da radiação , Idoso , Canal Anal/diagnóstico por imagem , Cateterismo/instrumentação , Cateterismo/métodos , Relação Dose-Resposta à Radiação , Incontinência Fecal/prevenção & controle , Humanos , Masculino , Diafragma da Pelve/diagnóstico por imagem , Radiografia , Planejamento da Radioterapia Assistida por Computador/métodos , Reto/diagnóstico por imagem
13.
Int J Radiat Oncol Biol Phys ; 83(2): 661-9, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22099035

RESUMO

PURPOSE: To investigate the effect of endorectal balloons (ERBs) on intrafraction and interfraction prostate motion during radiotherapy. METHODS AND MATERIALS: Thirty patients were treated with intensity-modulated radiotherapy, to a total dose of 80 Gy in 40 fractions. In 15 patients, a daily-inserted air-filled ERB was applied. Prostate motion was tracked, in real-time, using an electromagnetic tracking system. Interfraction displacements, measured before each treatment, were quantified by calculating the systematic and random deviations of the center of mass of the implanted transponders. Intrafraction motion was analyzed in timeframes of 150 s, and displacements >1 mm, >3 mm, >5 mm, and >7 mm were determined in the anteroposterior, left-right, and superoinferior direction, and for the three-dimensional (3D) vector. Manual table corrections, made during treatment sessions, were retrospectively undone. RESULTS: A total of 576 and 567 tracks have been analyzed in the no-ERB group and ERB group, respectively. Interfraction variation was not significantly different between both groups. After 600 s, 95% and 98% of the treatments were completed in the respective groups. Significantly fewer table corrections were performed during treatment fractions with ERB: 88 vs. 207 (p = 0.02). Intrafraction motion was significantly reduced with ERB. During the first 150 s, only negligible deviations were observed, but after 150 s, intrafraction deviations increased with time. This resulted in cumulative percentages of 3D-vector deviations >1 mm, >3 mm, >5 mm, and >7 mm that were 57.7%, 7.0%, 0.7%, and 0.3% in the ERB-group vs. 70.2%, 18.1%, 4.6%, and 1.4% in the no-ERB group after 600 s. The largest reductions in the ERB group were observed in the AP direction. These data suggest that a 5 mm CTV-to-PTV margin is sufficient to correct for intrafraction prostate movements when using an ERB. CONCLUSIONS: ERB significantly reduces intrafraction prostate motion, but not interfraction variation, and may in particular be beneficial for treatment sessions longer than 150 s.


Assuntos
Cateterismo/métodos , Movimento , Próstata , Neoplasias da Próstata/radioterapia , Reto , Ar , Cateterismo/instrumentação , Fracionamento da Dose de Radiação , Campos Eletromagnéticos , Marcadores Fiduciais , Humanos , Masculino , Neoplasias da Próstata/patologia , Radioterapia de Intensidade Modulada/métodos , Fatores de Tempo
14.
Int J Radiat Oncol Biol Phys ; 82(1): 145-52, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-20950951

RESUMO

PURPOSE: To explore the influence of functional changes and dosimetric parameters on specific incontinence-related anorectal complaints after prostate external beam radiotherapy and to estimate dose-effect relations for the anal wall and rectal wall. METHODS AND MATERIALS: Sixty patients, irradiated for localized prostate cancer, underwent anorectal manometry and barostat measurements to evaluate anal pressures, rectal capacity, and rectal sensory functions. In addition, 30 untreated men were analyzed as a control group. In 36 irradiated patients, the anal wall and rectal wall were retrospectively delineated on planning computed tomography scans, and dosimetric parameters were retrieved from the treatment plans. Functional and dosimetric parameters were compared between patients with and without complaints, focusing on urgency, incontinence, and frequency. RESULTS: After external beam radiotherapy, reduced anal pressures and tolerated rectal volumes were observed, irrespective of complaints. Patients with urgency and/or incontinence showed significantly lower anal resting pressures (mean 38 and 39 vs. 49 and 50 mm Hg) and lower tolerated rectal pressures (mean 28 and 28 vs. 33 and 34 mm Hg), compared to patients without these complaints. In patients with frequency, almost all rectal parameters were reduced. Several dosimetric parameters to the anal wall and rectal wall were predictive for urgency (e.g., anal D(mean)>38 Gy), whereas some anal wall parameters correlated to incontinence and no dose-effect relation for frequency was found. CONCLUSIONS: Anorectal function deteriorates after external beam radiotherapy. Different incontinence-related complaints show specific anorectal dysfunctions, suggesting different anatomic and pathophysiologic substrates: urgency and incontinence seem to originate from both anal wall and rectal wall, whereas frequency seems associated with rectal wall dysfunction. Also, dose-effect relations differed between these complaints. This implies that anal wall and rectal wall should be considered separate organs in radiotherapy planning.


Assuntos
Canal Anal/efeitos da radiação , Incontinência Fecal/fisiopatologia , Neoplasias da Próstata/radioterapia , Reto/efeitos da radiação , Idoso , Canal Anal/diagnóstico por imagem , Canal Anal/fisiopatologia , Análise de Variância , Estudos de Casos e Controles , Defecação/fisiologia , Defecação/efeitos da radiação , Relação Dose-Resposta à Radiação , Humanos , Modelos Lineares , Masculino , Manometria , Pressão , Radiografia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia Conformacional/efeitos adversos , Radioterapia Conformacional/métodos , Reto/diagnóstico por imagem , Reto/fisiopatologia , Sensação/fisiologia , Sensação/efeitos da radiação
15.
Clin Genitourin Cancer ; 9(2): 109-14, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21903486

RESUMO

BACKGROUND: High-precision radiotherapy with gold marker implantation is a standard technique for prostate cancer treatment. To provide insight into the beneficial effect of gold markers, the influence on treatment volume and radiation doses to healthy tissues was investigated. PATIENTS AND METHODS: Three consecutive treatment margins were constructed, for 10 patients with localized prostate cancer, to show the reduction of planning target volume (PTV): PTV 10 mm (no markers), PTV 7 mm (markers), and PTV 7/5 mm (markers and online correction). On planning computed tomography (CT) scan, the prostate, bladder, rectal wall, and anal canal were contoured. The treatment volume and radiation doses to surrounding organs were calculated. In 65 patients, with the online protocol and gold markers, late toxicity was evaluated. RESULTS: With gold markers a significant PTV reduction of 27% was achieved (P < .001). Subsequently, radiation dose reductions to the mean of 17% (± 4.5%) to the bladder, 19% (± 4.7%) to the anal canal, and 12% (± 3%) to the rectal wall, respectively were seen (P < .001). With 5-mm posterior margins an additional PTV reduction of 3.7% (P < .001) and total radiation dose reduction to the mean of 24% (± 4%), and 16% (± 4.5%) to anal canal and rectal wall, respectively were seen (P < .001). Late Grade 1-2 genitourinary and gastrointestinal toxicity was seen in 32%, and 33%, respectively. Grade 3 toxicity was less than 10%. CONCLUSIONS: This study showed a significant reduction of treatment volume and radiation doses to healthy tissues with intraprostatic gold markers.


Assuntos
Ouro , Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Radioterapia (Especialidade)/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Humanos , Masculino , Radiografia , Radioterapia Conformacional/efeitos adversos
16.
Radiother Oncol ; 101(3): 465-70, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21872953

RESUMO

BACKGROUND AND PURPOSE: To investigate the effect of an endorectal balloon (ERB) on anal wall (Awall) and rectal wall (Rwall) doses in high-dose post-prostatectomy intensity-modulated radiotherapy (IMRT). MATERIALS AND METHODS: For 20 patients, referred for salvage IMRT after prostatectomy for prostate cancer, two planning CT-scans were performed: one with and one without an air-filled ERB. A planning target volume (PTV) was defined, using international guidelines. Furthermore, the Awall and Rwall were delineated. In both the scans, IMRT plans were generated with a prescribed dose of 70 Gy. The mean dose (D(mean)), maximum dose, minimum dose, and volumes exposed to doses ranging from ≥ 20 to ≥ 70 Gy (V(20)-V(70)) to the Awall and Rwall were calculated. Finally, inner Rwall surface areas exposed to doses ranging from ≥ 20 to ≥ 70 Gy (A(20)-A(70)) were calculated. Dose-parameters were compared between plans with and without ERB. RESULTS: All Awall parameters, except V(70), were significantly reduced by the ERB with an overall D(mean) reduction of 6 Gy. Absolute reductions in dose-volume parameters varied from 5% to 11%. Significantly reduced Rwall V(30), V(40), and A(40) were observed with ERB, irrespective of the target volume size. CONCLUSION: ERB application significantly reduces Awall and to a lesser degree Rwall doses in high-dose post-prostatectomy IMRT.


Assuntos
Canal Anal/efeitos da radiação , Prostatectomia , Neoplasias da Próstata/radioterapia , Radioterapia de Intensidade Modulada/métodos , Reto/efeitos da radiação , Cateterismo , Humanos , Masculino , Neoplasias da Próstata/cirurgia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
17.
Radiother Oncol ; 95(3): 277-82, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20451274

RESUMO

BACKGROUND AND PURPOSE: Endorectal balloons (ERBs) are being used in prostate radiotherapy for prostate immobilization and rectal wall (Rwall) sparing. Some of their aspects, however, have been questioned, like patient's tolerance and their value in modern high-precision radiotherapy. This paper gives an overview of published data concerning ERB application in prostate radiotherapy. MATERIALS AND METHODS: Systematic literature review based on PubMed/MEDLINE database searches. 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. Clinical data, however, are scarce, as only one study shows reduced late rectal damage. There is no consensus about the immobilizing properties of ERBs and it is recommended to use additional set-up and correction protocols, especially because there are potential pitfalls. CONCLUSION: ERBs seem well-tolerated and in planning studies reduce anorectal wall doses. This may lead to reduced anorectal toxicity, although clinical studies are warranted to confirm this hypothesis and to further investigate the immobilizing properties of ERBs, preferably in combination with advanced techniques for position verification.


Assuntos
Neoplasias da Próstata/radioterapia , Lesões por Radiação/prevenção & controle , Reto/efeitos da radiação , Cateterismo , Humanos , Imobilização , Masculino , Terapia com Prótons , Planejamento da Radioterapia Assistida por Computador , Radioterapia Conformacional , Radioterapia de Intensidade Modulada
18.
Radiother Oncol ; 93(1): 131-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19523704

RESUMO

BACKGROUND AND PURPOSE: To investigate the anal wall (Awall) sparing effect of an endorectal balloon (ERB) in 3D conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) for prostate cancer. MATERIALS AND METHODS: In 24 patients with localized prostate carcinoma, two planning CT-scans were performed: with and without ERB. A prostate planning target volume (PTV) was defined, and the Awall was delineated, using two different methods. Three-field and 4-field 3D-CRT plans, and IMRT plans were generated with a prescription dose of 78Gy. In 144 treatment plans, the minimum dose (D(min)), maximum dose (D(max)), and mean dose (D(mean)) to the Awall were calculated, as well as the Awall volumes exposed to doses ranging from >or=20Gy to >or=70Gy (V(20)-V(70), respectively). RESULTS: In the 3D-CRT plans, an ERB significantly reduced D(mean), D(max), and V(30)-V(70). For IMRT all investigated dose parameters were significantly reduced by the ERB. The absolute reduction of D(mean) was 12Gy in 3D-CRT and was 7.5Gy in IMRT for both methods of Awall delineation. CONCLUSIONS: Application of an ERB showed a significant Awall sparing effect in both 3D-CRT and IMRT. This may lead to reduced late anal toxicity in prostate radiotherapy.


Assuntos
Adenocarcinoma/radioterapia , Canal Anal/efeitos da radiação , Neoplasias da Próstata/radioterapia , Radioterapia Conformacional/métodos , Radioterapia de Intensidade Modulada/métodos , Adenocarcinoma/patologia , Idoso , Cateterismo , Estudos de Coortes , Relação Dose-Resposta à Radiação , Seguimentos , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias da Próstata/patologia , Lesões por Radiação/prevenção & controle , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/instrumentação , Radioterapia de Intensidade Modulada/instrumentação , Medição de Risco , Resultado do Tratamento
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