Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Lancet Oncol ; 22(5): 702-715, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33862000

RESUMO

BACKGROUND: Treatment of locally advanced rectal cancer with chemoradiotherapy, surgery, and adjuvant chemotherapy controls local disease, but distant metastases remain common. We aimed to assess whether administering neoadjuvant chemotherapy before preoperative chemoradiotherapy could reduce the risk of distant recurrences. METHODS: We did a phase 3, open-label, multicentre, randomised trial at 35 hospitals in France. Eligible patients were adults aged 18-75 years and had newly diagnosed, biopsy-proven, rectal adenocarcinoma staged cT3 or cT4 M0, with a WHO performance status of 0-1. Patients were randomly assigned (1:1) to either the neoadjuvant chemotherapy group or standard-of-care group, using an independent web-based system by minimisation method stratified by centre, extramural extension of the tumour into perirectal fat according to MRI, tumour location, and stage. Investigators and participants were not masked to treatment allocation. The neoadjuvant chemotherapy group received neoadjuvant chemotherapy with FOLFIRINOX (oxaliplatin 85 mg/m2, irinotecan 180 mg/m2, leucovorin 400 mg/m2, and fluorouracil 2400 mg/m2 intravenously every 14 days for 6 cycles), chemoradiotherapy (50 Gy during 5 weeks and 800 mg/m2 concurrent oral capecitabine twice daily for 5 days per week), total mesorectal excision, and adjuvant chemotherapy (3 months of modified FOLFOX6 [intravenous oxaliplatin 85 mg/m2 and leucovorin 400 mg/m2, followed by intravenous 400 mg/m2 fluorouracil bolus and then continuous infusion at a dose of 2400 mg/m2 over 46 h every 14 days for six cycles] or capecitabine [1250 mg/m2 orally twice daily on days 1-14 every 21 days]). The standard-of-care group received chemoradiotherapy, total mesorectal excision, and adjuvant chemotherapy (for 6 months). The primary endpoint was disease-free survival assessed in the intention-to-treat population at 3 years. Safety analyses were done on treated patients. This trial was registered with EudraCT (2011-004406-25) and ClinicalTrials.gov (NCT01804790) and is now complete. FINDINGS: Between June 5, 2012, and June 26, 2017, 461 patients were randomly assigned to either the neoadjuvant chemotherapy group (n=231) or the standard-of-care group (n=230). At a median follow-up of 46·5 months (IQR 35·4-61·6), 3-year disease-free survival rates were 76% (95% CI 69-81) in the neoadjuvant chemotherapy group and 69% (62-74) in the standard-of-care group (stratified hazard ratio 0·69, 95% CI 0·49-0·97; p=0·034). During neoadjuvant chemotherapy, the most common grade 3-4 adverse events were neutropenia (38 [17%] of 225 patients) and diarrhoea (25 [11%] of 226). During chemoradiotherapy, the most common grade 3-4 adverse event was lymphopenia (59 [28%] of 212 in the neoadjuvant chemotherapy group vs 67 [30%] of 226 patients in the standard-of-care group). During adjuvant chemotherapy, the most common grade 3-4 adverse events were lymphopenia (18 [11%] of 161 in the neoadjuvant chemotherapy group vs 42 [27%] of 155 in the standard-of-care group), neutropenia (nine [6%] of 161 vs 28 [18%] of 155), and peripheral sensory neuropathy (19 [12%] of 162 vs 32 [21%] of 155). Serious adverse events occurred in 63 (27%) of 231 participants in the neoadjuvant chemotherapy group and 50 (22%) of 230 patients in the standard-of-care group (p=0·167), during the whole treatment period. During adjuvant therapy, serious adverse events occurred in 18 (11%) of 163 participants in the neoadjuvant chemotherapy group and 36 (23%) of 158 patients in the standard-of-care group (p=0·0049). Treatment-related deaths occurred in one (<1%) of 226 patients in the neoadjuvant chemotherapy group (sudden death) and two (1%) of 227 patients in the standard-of-care group (one sudden death and one myocardial infarction). INTERPRETATION: Intensification of chemotherapy using FOLFIRINOX before preoperative chemoradiotherapy significantly improved outcomes compared with preoperative chemoradiotherapy in patients with cT3 or cT4 M0 rectal cancer. The significantly improved disease-free survival in the neoadjuvant chemotherapy group and the decreased neurotoxicity indicates that the perioperative approach is more efficient and better tolerated than adjuvant chemotherapy. Therefore, the PRODIGE 23 results might change clinical practice. FUNDING: Institut National du Cancer, Ligue Nationale Contre le Cancer, and R&D Unicancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia , Neoplasias Retais/terapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Feminino , Fluoruracila/efeitos adversos , Fluoruracila/uso terapêutico , Humanos , Irinotecano/efeitos adversos , Irinotecano/uso terapêutico , Leucovorina/efeitos adversos , Leucovorina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Oxaliplatina/efeitos adversos , Oxaliplatina/uso terapêutico , Qualidade de Vida , Neoplasias Retais/mortalidade , Neoplasias Retais/psicologia
2.
Turk J Gastroenterol ; 31(10): 695-705, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33169707

RESUMO

BACKGROUND/AIMS: The Bretagne-Pays de la Loire cancer observatory, an oncology network created by the French Ministry of Health, is specifically dedicated to assess the use of new targeted anticancer therapies in routine practice. In line with the French National Cancer III program, our cancer network set up a real-life cohort, which is independent of the pharmaceutical industry, for patients with colorectal cancer to monitor patient safety and quality of care and promote pharmacovigilance. MATERIALS AND METHODS: Panitumumab monotherapy was assessed in 243 patients with wild-type Kirsten rat sarcoma who were treated for metastatic colorectal cancer (mCRC) between July 2008 and December 2010 after prior chemotherapy using oxaliplatine and irinotecan. This was a post-European medicine agency marketing (EMA-M) study Results: This study shed light on the best practices, strategic adaptations, clinical results (treatment objective responses, 13%; progression free survival, 2.99 months [2.73-3.15]; and overall survival, 6.8 months [5.49-8.38]) as well as expected or unexpected (grade 3 or 4: 11.5%) secondary effects in the phase IV panitumumab treatment of mCRC. CONCLUSION: Our results are similar to those by Amado whose phase III study led to obtaining EMA-M for panitumumab and tend to confirm the antitumor activity of this antiepidermal growth factor receptor antibody in the treatment of mCRC. In addition, our results opened avenues to further assessment of panitumumab use as monotherapy as well as its benefit-risk ratio while taking into account the patients' general and clinical characteristics. In 2012, the French National Authority for Health appended these data to the panitumumab transparency committee report.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Panitumumabe/uso terapêutico , Vigilância de Produtos Comercializados , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/genética , Feminino , França , Geriatria , Humanos , Masculino , Oncologia , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Resultado do Tratamento
3.
Cancers (Basel) ; 12(3)2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-32182949

RESUMO

Curative radiotherapy for prostate cancer is common in the elderly. However, concerns about potential toxicity have inhibited access to radiotherapy for this population, for whom preserving quality of life (QoL) is crucial. The primary endpoint was to identify predictors of impaired QoL in men aged 75 years or older treated with curative intent radiotherapy with or without androgen deprivation therapy (ADT) for localized prostate cancer. We prospectively performed comprehensive geriatric assessment (CGA) and administered QoL questionnaires to 208 elderly (>75 years) patients prior to, plus two and six months after, radiotherapy (NCT02876237). The median age of the patients was 77 years (range 75-89). At the start of the study, comorbidities were highlighted in 65% of patients: 23% were depressed, 23% had cognitive impairment, and 16% had reduced independence. At six months, 9% of patients had a consistently decreased QoL (>20 points), and a further 16% had a more moderate reduction (10 to 20 points) in QoL. None of the parameters studied (tumor characteristic, treatment, or oncogeriatric parameters) were predictive of a reduced QoL following radiotherapy. Though co-existing geriatric impairment was common, QoL was maintained for 75% of patients six months after radiotherapy. CGA was poorly predictive of tolerance of prostatic radiotherapy. Geriatric assessments dedicated to quality of life following radiotherapy need to be developed.

4.
PLoS One ; 13(4): e0194173, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29630602

RESUMO

INTRODUCTION: Radiotherapy can diminish quality of life (QoL) for prostate cancer patients. Our objective was to evaluate the effect of radiotherapy on QoL in men aged 75 years or older treated with radiotherapy for a localized prostate cancer, and to identify predictors of reduced QoL. PATIENTS AND METHODS: We prospectively administered a battery of geriatric (MNA, GDS, Get up and Go Test, CIRS-G, ADL, IADL, MMSE), toxicity (IPSS; IIEF 5), and QoL (QLQ C30) screening tests in 100 elderly patients before and two months after prostate cancer radiotherapy (NCT 02876237). Patients ≥ 75 years undergoing radiotherapy with a curative intent for localized prostate cancer with or without androgen deprivation therapy (ADL) were eligible for study inclusion. Correlations between patient-assessed QoL and tumor characteristics, radiotherapy treatment or CGA parameters were sought using the Fisher or the Mann and Whitney tests. Changes in QoL parameters over time were analyzed using the Wilcoxon signed-rank test. RESULTS: At study entry, scores for IADL impairments were present in 51%, reduced autonomy in activities of daily living in 16%, cognitive impairment found in 20%, depression-related symptoms in 31%, and 66% of patients had significant co-morbidities. Eight percent were judged to be at risk of fall and 2% were found to be undernourished. Severely impaired (IPSS ≥ 20) urinary function was observed in 11.2% and 13.5% of patients before and two months after completion of radiotherapy respectively. Significantly decreased QoL (> 20 points) at two months after treatment was found in 13% of patients and a moderate but clinically relevant reduction (10 to 20 points) in 17% of patients. No tumor characteristic, treatment, or oncogeriatric parameter was predictive of reduced QoL following prostate cancer radiotherapy. CONCLUSION: Despite sometimes markedly diminished oncogeriatric parameters, prostate cancer radiotherapy was generally well tolerated in these elderly patients. We found no predictive factor to determine which patients would experience impaired quality of life following radiotherapy.


Assuntos
Avaliação Geriátrica , Neoplasias da Próstata/radioterapia , Qualidade de Vida , Radioterapia , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Humanos , Masculino , Estudos Prospectivos
5.
Oncotarget ; 8(9): 15924-15933, 2017 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-27764781

RESUMO

BACKGROUND: Gefitinib is an oral EGFR tyrosine kinase inhibitors which may act as a radiosensitizer. PATIENTS AND METHODS: This phase II study evaluated the efficacy of gefitinib 250 mg once daily in combination with thoracic radiotherapy (66 Gy in 6.5 weeks, 2 Gy/day, 5 fractions/week) followed by consolidation chemotherapy (IV cisplatin and vinorelbine) as first line treatment in a population of unselected stage IIIB NSCLC patients according to EGFR mutation status. RESULTS: Due to a low accrual rate in this study, the sample size (n = 50) was not reached. Sixteen patients were included in four centers, 50% had adenocarcinoma and 75% were male. Genomic alterations (7 patients studied) retrieved TP53 mutation in 2 patients and no EGFR mutation. Four weeks after radiotherapy, 3 patients (19%) had a partial response, 6 (38%) had a stable disease, and 7 had a progression (44%). Median overall survival was 11 months and median progression-free survival was 5 months. At the time of the last contact, 5 patients (31%) were still alive. Main toxicities were gastrointestinal (81%), cutaneous (81%), general (56%), and respiratory (50%). There were 12>G3 adverse events in 7 (47%) patients, and there was one toxic-death during the concomitant period due to an interstitial pneumonitis. There were two possible adverse events-related deaths during the chemotherapy period (pulmonary embolism (n = 1) and sudden death after the administration of the 3rd course of chemotherapy (n = 1)). CONCLUSION: The benefit of Gefitinib-RT could not be confirmed due to premature trial discontinuation. Further evaluation is required, especially in patients with EGFR mutated NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Quinazolinas/uso terapêutico , Adulto , Idoso , Carcinoma Pulmonar de Células não Pequenas/patologia , Intervalo Livre de Doença , Feminino , Gefitinibe , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Quinazolinas/administração & dosagem
6.
Int J Radiat Oncol Biol Phys ; 79(3): 823-8, 2011 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20452732

RESUMO

PURPOSE: To quantify the impact of preradiotherapy 18F-fluoro-2-deoxyglucose positron-emission tomography (FDG-PET) on treatment strategy and radiotherapy planning for patients with Stage I/II Hodgkin disease included in a large prospective multicenter study. PATIENTS AND METHODS: Conventional computed tomography and FDG-PET were performed just before the planned radiotherapy. The radiotherapy plan was first elaborated under blinded conditions for FDG-PET data. Then, the medical staff was asked to confirm or not confirm the treatment strategy and, if appropriate, to modify the radiotherapy plan based on additional information from FDG-PET. RESULTS: Between January 2004 and January 2006, 137 patients were included (124 were available for analysis) in 11 centers (108 adults, 16 children). All but 1 patient had received chemotherapy before inclusion. Prechemotherapy work-up included FDG-PET for 61 patients, and data were available for elaboration of the first radiotherapy plan. Based on preradiotherapy FDG-PET data, the radiotherapy was cancelled in 6 patients (4.8%), and treatment plan modifications occurred in 16 patients (12.9%): total dose (11 patients), CTV volume (5 patients), number of beam incidences (6 patients), and number of CTV (6 patients). The concordance between the treatment strategies with or without preradiotherapy FDG-PET was 82.3%. Concordance results were not significantly different when prechemotherapy PET-CT information was available. CONCLUSION: Preradiotherapy FDG-PET for treatment planning in Hodgkin lymphoma may lead to significant modification of the treatment strategy and the radiotherapy planning in patients with Stage I or II Hodgkin disease, even in those who have undergone FDG-PET as part of the prechemotherapy work-up.


Assuntos
Fluordesoxiglucose F18 , Doença de Hodgkin/diagnóstico por imagem , Doença de Hodgkin/radioterapia , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia Conformacional/métodos , Tomografia Computadorizada por Raios X/métodos , Carga Tumoral , Adulto Jovem
8.
Bull Cancer ; 93(11): 1101-5, 2006 Nov.
Artigo em Francês | MEDLINE | ID: mdl-17145579

RESUMO

RTOG and EORTC trials have paved the way of the combination of radiation therapy and androgen suppression. Localized carcinoma with intermediate prognostic factors (cT2b, Gleason 7, or baseline PSA ranging between 10 and 20 ng/mL) may be submitted to a 4-month complete androgene blockade with 2 months before irradiation, unless to include patients in ongoing randomized trials. High risk cancers (cT2c, or Gleason > 7, or PSA > 20 ng/ml) should receive a 4-month or 6-month complete androgen blockade (RTOG trial 86-10), knowing that the results of EORTC trial 22961 are eagerly expected to tell us whether a 3- year androgen suppression is preferable. Very high risk prostate cancers, T3-4 N0 M0 or pelvic lymph node involvement (c or pN1) whatever the UICC T stage, need a long term androgen suppression of 3 years or more.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Terapia Neoadjuvante/métodos , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Neoplasias Hormônio-Dependentes/radioterapia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Antagonistas de Androgênios/uso terapêutico , Humanos , Masculino , Neoplasias Hormônio-Dependentes/patologia , Neoplasias da Próstata/patologia , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
Cancer Radiother ; 9(6-7): 394-8, 2005 Nov.
Artigo em Francês | MEDLINE | ID: mdl-16226044

RESUMO

RTOG and EORTC randomised phase III trials investigated combination of radiation therapy and hormonal treatment in locally advanced prostate cancer T2c-T4 N0-1 M0 (UICC 2002). Complete androgen blockade initiated 2 months prior to starting radiotherapy and stopped at the completion of radiotherapy vs radiation therapy alone, increased overall survival in patients with Gleason score 2-6. Adjuvant androgen suppression started at the end of the radiotherapy and continued indefinitely improved significantly overall survival of patients Gleason score 8 to 10. Complete androgen blockade in two months before and two months during radiation followed by 24 additional months of LHRH analogue alone improved overall survival of patients Gleason score 8-10 with respect to CAB alone. EORTC trial 22861 has shown that androgen suppression with LHRH analogue given during and for 3 years after external irradiation improved overall survival whatever the Gleason score. The role of hormonal treatment is currently assessed in localized prostate cancer (T1-2 N0) with poor prognostic factors: Gleason score 8-10, PSA>20 ng/ml.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Terapia Combinada , Humanos , Masculino , Prognóstico , Neoplasias da Próstata/patologia , Sobrevida , Resultado do Tratamento
10.
Int J Radiat Oncol Biol Phys ; 60(2): 623-35, 2004 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-15380600

RESUMO

PURPOSE: With higher radiation dose, higher cure rates have been reported in prostate cancer patients. The extra margin needed to account for prostate motion, however, limits the level of dose escalation, because of the presence of surrounding organs at risk. Knowledge of the precise position of the prostate would allow significant reduction of the treatment field. Better localization of the prostate at the time of treatment is therefore needed, e.g. using a cone-beam computed tomography (CT) system integrated with the linear accelerator. Localization of the prostate relies upon manual delineation of contours in successive axial CT slices or interactive alignment and is fairly time-consuming. A faster method is required for on-line or off-line image-guided radiotherapy, because of prostate motion, for patient throughput and efficiency. Therefore, we developed an automatic method to localize the prostate, based on 3D gray value registration. METHODS AND MATERIALS: A study was performed on conventional repeat CT scans of 19 prostate cancer patients to develop the methodology to localize the prostate. For each patient, 8-13 repeat CT scans were made during the course of treatment. First, the planning CT scan and the repeat CT scan were registered onto the rigid bony structures. Then, the delineated prostate in the planning CT scan was enlarged by an optimum margin of 5 mm to define a region of interest in the planning CT scan that contained enough gray value information for registration. Subsequently, this region was automatically registered to a repeat CT scan using 3D gray value registration to localize the prostate. The performance of automatic prostate localization was compared to prostate localization using contours. Therefore, a reference set was generated by registering the delineated contours of the prostates in all scans of all patients. Gray value registrations that showed large differences with respect to contour registrations were detected with a chi(2) analysis and were removed from the data set before further analysis. RESULTS: Comparing gray value registration to contour registration, we found a success rate of 91%. The accuracy for rotations around the left-right, cranial-caudal, and anterior-posterior axis was 2.4 degrees, 1.6 degrees, and 1.3 degrees (1 SD), respectively, and for translations along these axes 0.7, 1.3, and 1.2 mm (1 SD), respectively. A large part of the error is attributed to uncertainty in the reference contour set. Automatic prostate localization takes about 45 seconds on a 1.7 GHz Pentium IV personal computer. CONCLUSIONS: This newly developed method localizes the prostate quickly, accurately, and with a good success rate, although visual inspection is still needed to detect outliers. With this approach, it will be possible to correct on-line or off-line for prostate movement. Combined with the conformity of intensity-modulated dose distributions, this method might permit dose escalation beyond that of current conformal approaches, because margins can be safely reduced.


Assuntos
Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Planejamento da Radioterapia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Humanos , Masculino , Neoplasias da Próstata/radioterapia , Radioterapia Assistida por Computador , Radioterapia Conformacional , Glândulas Seminais/diagnóstico por imagem
11.
Eur J Cancer ; 40(11): 1674-81, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15251156

RESUMO

Late toxicity and other serious adverse events (SAE) were analysed in the European Organisation for Research and Treatment of Cancer (EORTC) trial 22863. The study evaluated the value of adjuvant endocrine treatment for locally advanced prostate cancer treated with radiotherapy. From 1987 to 1995, 415 patients were randomised. There was long-term toxicity information for 377 patients (91%). Median age was 70 years (range 50-80 years). Median follow-up for late toxicity was 42 months (range 3-136 months). Toxicity was graded according to a modified Radiotherapy and Oncology Group (RTOG) scale. Other late SAE, that was not classified as severe treatment toxicity, but were still life-threatening, were also assessed. There were 72 patients with grade 2, 10 patients with grade 3 and 4 patients with grade 4 toxicity. There were 20 patients with other late SAE, who were grouped according to their relationship to treatment; likely related (n = 1), unrelated (n = 7) and not assessable (n = 12). Although four treatment-related deaths (1%) occurred, grade 3 or 4 late complications were less than 5%.


Assuntos
Neoplasias da Próstata/radioterapia , Lesões por Radiação/complicações , Idoso , Idoso de 80 Anos ou mais , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Radioterapia/efeitos adversos , Fatores de Tempo
12.
Int J Radiat Oncol Biol Phys ; 59(2): 595-601, 2004 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15145181

RESUMO

AIM: Numerous studies reported the use of ultrasound image-guidance system to assess and correct patient setup during radiotherapy for prostate cancer. We conducted a study to demonstrate and quantify prostate displacement resulting from pressure of the probe on the abdomen during transabdominal ultrasound image acquisition for prostate localization. MATERIAL AND METHODS: Ten healthy volunteers were asked to undergo one imaging procedure. The procedure was performed in a condition that simulates the localization of prostate during online ultrasound guidance. A 3D ultrasound machine was used. The procedure started with the placement of the probe on the abdomen above the pubis symphysis. The probe was tilted in a caudal and posterior direction until the prostate and seminal vesicle were visualized. The probe was then fixed with a rigid arm, which maintained the probe in a static position during image acquisition. The probe was then moved, in a short time, stepwise toward the prostate, acquiring images at each step. The prostate and seminal vesicles were identified and selected in all planes. The first 3D volume was used as reference 1, to which all other scans were matched using a gray value matching algorithm. RESULTS: Prostate motion was quantified as a 3D translation relative to the patient coordinate system. The resulting translations represented the amount of prostate movement as a function of probe displacement. Between 7 and 11 images were obtained per volunteer, with a maximal probe displacement ranging between 3 and 6 cm. Prostate displacement was measured in all volunteers for all the probe steps and in all directions. The largest displacements occurred in the posterior direction in all volunteers. The absolute prostate motion was less than 5 mm in 100% of the volunteers after 1 cm of probe displacement, in 80% after 1.5 cm, in 40% after 2 cm, in 10% after 2.5 cm, and 0% after 3 cm. To achieved a good-quality ultrasound images, the probe requires an average displacement of 1.2 cm, and this results in an average prostate displacement of 3.1 mm. No correlations were observed between prostate motion and prostate-probe distance or bladder size. CONCLUSION: Probe pressure during ultrasound image acquisition causes prostate displacement, which is correlated to the amount of probe displacement from initial contact. The induced uncertainty associated with this process needs to be carefully evaluated to determine a safe margin to be employed during online ultrasound image-guided radiotherapy of the prostate.


Assuntos
Movimento , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Adulto , Humanos , Imageamento Tridimensional , Masculino , Pressão , Glândulas Seminais/diagnóstico por imagem , Ultrassonografia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA