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1.
J Cancer Educ ; 34(3): 488-497, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-29435742

RESUMO

High-quality oncology consultation includes patient-oriented communication tailored to patients' individualized needs. Common methods used in studies to increase question-asking are prompt lists and coaching pre-consultations. However, our patients were encouraged to ask questions by the physician during their visit. We aimed to estimate the quantity, nature, and variation of their questions when they were invited to ask by their oncologist. During radiotherapy consultations from 2012 to 2016, patient's questions were deliberately elicited and physician-transcribed. We derived mean and median number of questions per patient, variance by patient factors, and a taxonomy of subjects using thematic analysis. Three hundred ninety-six patients asked 2386 questions, median asked per patient = 6 (interquartile range = 4). We found significant variance with age (mean = 6.9 questions for < 60 years, 5.4 for ≥ 70 years) p = 0.018, insurance type (mean = 4.7 for Medicaid, 7.2 for private insurance) p = 0.0004, and tumor site (mean number of questions: skin = 4.6, lymphoma = 5.2, lung = 5.8, breast = 6.1, prostate = 6.3, rectum = 6.7 head and neck = 6.9, brain = 7.0, bladder = 7.2, anus = 8.8, others = 5.8) p = 0.0440. Of the diverse set of 57 topics, the commonest were 1. logistics, 2. radiotherapy details, 3. side effects, 4. diagnosis, and 5. stage and prognosis. Only 17 topics were asked by more > 10% of patients and 40 topics were asked by < 10% of patients. With median of 6 questions, it is practicable to routinely elicit and address individualized information needs. Potential barriers may be older and underinsured patients. The wide variety of topics, often pertaining to individuals' case, suggests that cancer clinicians should take time-out during consultation to elicit patients' questions to accomplish best-practice communication.


Assuntos
Comunicação , Necessidades e Demandas de Serviços de Saúde/estatística & dados numéricos , Disseminação de Informação/métodos , Neoplasias/terapia , Educação de Pacientes como Assunto/métodos , Participação do Paciente/métodos , Encaminhamento e Consulta/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Tomada de Decisões , Feminino , Humanos , Masculino , Oncologia , Pessoa de Meia-Idade , Neoplasias/psicologia , Participação do Paciente/psicologia , Relações Médico-Paciente , Médicos/psicologia , Estudos Retrospectivos , Adulto Jovem
3.
Postgrad Med J ; 87(1031): 585-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21708821

RESUMO

BACKGROUND The rising cancer incidence in developing countries outpaces easy access to care. Time and effort spent on travel for care is a burden to patients and detracts from patient centredness, efficiency, and equitability. In Trinidad and Tobago, significant distress was observed among patients who made long journeys to the single public cancer clinic. The journey time among non-radiotherapy patients was measured. METHODS Over 19 weekdays in June 2007, the study assessed estimated travel time per visit (ETT), reason for visit for care, and number of visits per patient during their treatment course up to the time of study, and compared the findings with ETT to nearest centres for the US population. RESULTS 1447 episodes of care utilised 5296 h of patient travel time. Median ETT was 3.75 h (IQR 2-5 h, range 0.5-9 h). 74.1% of patients spent 2.25-9 h ETT. 44% of patients spent >4 h ETT. Median number of visits per patient was 34 (IQR 23-43; range 13-62). Median total ETT per patient was 127.5 h. Median ETT to the centre (1.75 h) was eight times greater than in the USA (13 min). More than 70% of patients attended for reasons other than chemotherapy. CONCLUSIONS Cancer patients endured a burden of long travel times in 2007. The prevailing policy of the Ministry of Health to build a single centralised modern centre would not have alleviated this burden. Based on these findings, three outlying cancer clinics were created which now provide non-radiotherapy oncology management of patients nearer their homes.


Assuntos
Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Neoplasias/terapia , Área de Atuação Profissional/estatística & dados numéricos , Viagem/estatística & dados numéricos , Países em Desenvolvimento , Geografia , Humanos , Neoplasias/epidemiologia , Estudos Retrospectivos , População Rural/estatística & dados numéricos , Soluções , Fatores de Tempo , Trinidad e Tobago/epidemiologia , População Urbana/estatística & dados numéricos
4.
Int J Radiat Oncol Biol Phys ; 71(3): 916-25, 2008 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-18395358

RESUMO

PURPOSE: To assess the positioning accuracy using two-dimensional kilovoltage (2DkV) imaging and three-dimensional cone beam CT (CBCT) in patients with head and neck (H&N) cancer receiving radiation therapy. To assess the benefit of patient-specific headrest. MATERIALS AND METHODS: All 21 patients studied were immobilized using thermoplastic masks with either a patient-specific vacuum bag (11 of 21, IMA) or standard clear plastic (10 of 21, IMB) headrests. Each patient was imaged with a pair of orthogonal 2DkV images in treatment position using onboard imaging before the CBCT procedure. The 2DkV and CBCT images were acquired weekly during the same session. The 2DkV images were reviewed by oncologists and also analyzed by a software tool based on mutual information (MI). RESULTS: Ninety-eight pairs of assessable 2DkV-CBCT alignment sets were obtained. Systematic and random errors were <1.6 mm for both 2DkV and CBCT alignments. When we compared shifts determined by CBCT and 2DkV for the same patient setup, statistically significant correlations were observed in all three major directions. Among all CBCT couch shifts, 4.1% > or = 0.5 cm and 18.7% > or = 0.3 cm, whereas among all 2DkV (MI) shifts, 1.7% > or = 0.5 cm and 11.2% > or = 0.3 cm. Statistically significant difference was found on anteroposterior direction between IMA and IMB with the CBCT alignment only. CONCLUSIONS: The differences between 2D and 3D alignments were mainly caused by the relative flexibility of certain H&N structures and possibly by rotation. Better immobilization of the flexible neck is required to further reduce the setup errors for H&N patients receiving radiotherapy.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/radioterapia , Imageamento Tridimensional/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada Espiral/métodos , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
Int J Radiat Oncol Biol Phys ; 72(1): 210-9, 2008 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-18722272

RESUMO

PURPOSE: Auto-propagation of anatomic regions of interest from the planning computed tomography (CT) scan to the daily CT is an essential step in image-guided adaptive radiotherapy. The goal of this study was to quantitatively evaluate the performance of the algorithm in typical clinical applications. METHODS AND MATERIALS: We had previously adopted an image intensity-based deformable registration algorithm to find the correspondence between two images. In the present study, the regions of interest delineated on the planning CT image were mapped onto daily CT or four-dimensional CT images using the same transformation. Postprocessing methods, such as boundary smoothing and modification, were used to enhance the robustness of the algorithm. Auto-propagated contours for 8 head-and-neck cancer patients with a total of 100 repeat CT scans, 1 prostate patient with 24 repeat CT scans, and 9 lung cancer patients with a total of 90 four-dimensional CT images were evaluated against physician-drawn contours and physician-modified deformed contours using the volume overlap index and mean absolute surface-to-surface distance. RESULTS: The deformed contours were reasonably well matched with the daily anatomy on the repeat CT images. The volume overlap index and mean absolute surface-to-surface distance was 83% and 1.3 mm, respectively, compared with the independently drawn contours. Better agreement (>97% and <0.4 mm) was achieved if the physician was only asked to correct the deformed contours. The algorithm was also robust in the presence of random noise in the image. CONCLUSION: The deformable algorithm might be an effective method to propagate the planning regions of interest to subsequent CT images of changed anatomy, although a final review by physicians is highly recommended.


Assuntos
Algoritmos , Neoplasias/diagnóstico por imagem , Planejamento da Radioterapia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Masculino , Neoplasias/radioterapia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Sistemas de Informação em Radiologia , Planejamento da Radioterapia Assistida por Computador/normas
6.
Urol Oncol ; 36(1): 9.e19-9.e25, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28993060

RESUMO

PURPOSE: To assess characteristics and outcome of patients treated with radiotherapy for muscle-invasive bladder cancer at 44 community-based radiotherapy centers and compare these to those on clinical trials. MATERIALS AND METHODS: We reviewed 155 patients who had been treated from 2010 to 2014. Overall survival and progression-free survival were estimated using the Kaplan-Meier method. Results were compared to a pooled analysis of 6 Radiation Therapy Oncology Group (RTOG) protocols. RESULTS: What stood out was that our patients' characteristics were significantly inferior than those on RTOG studies: lower rate of complete transurethral resection of bladder tumor: 36.8% vs. 70% (P<0.0001), higher median age: 79 years vs. 66 (P<0.0001), more medically inoperable: (51.0%) vs. 0% in RTOG (P<0.001), and 46.9% had refused surgery. Fewer patients underwent concurrent chemotherapy: 56.1% vs. 100% (P<0.0001). It was also striking that at median follow-up 12.6 months (range: 3.1-49.2), the 36-month overall survival was 51.3% for those who refused surgery vs. 24.5% for medically inoperable (P = 0.009); 58.1% with complete transurethral resection of bladder tumor vs. 29.8% if incomplete (P = 0.07); 54.3% with chemoradiotherapy (CRT) vs. 17.2% without (P = 0.03); 66.3% for those who refused surgery and had CRT vs. 38.9% for medically inoperable who had CRT (P = 0.04). CONCLUSIONS: The cohort at community-based centers was older, more medically inoperable, and less likely to receive CRT than clinical trial patients. This suggests that we may not be able to apply trial-derived regimens for many patients in this setting. There is a pressing need to find treatment options for such patients, especially given the aging population. Survival of medically operable CRT patients was comparable to results of RTOG protocols notwithstanding this study's smaller sample size, retrospective nature and suboptimal documentation of patient characteristics.


Assuntos
Quimiorradioterapia/métodos , Neoplasias da Bexiga Urinária/radioterapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Neoplasias da Bexiga Urinária/patologia
7.
Med Dosim ; 43(1): 69-73, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29031904

RESUMO

When contemplating how to treat head and neck primary cancers and regional lymph nodes with radiotherapy, we often select the contemporary intensity-modulated radiotherapy (IMRT) without much consideration of older methods that may give fewer side effects and be more cost-effective. For an 87-year-old female with a 1.5-cm Merkel cell carcinoma (MCC) located 1.5 cm lateral to the orbital rim, we were challenged to deliver 50 Gy to comprehensive elective nodal regions and 70 Gy to the primary. We were particularly concerned about the potential adverse acute effects of radiotherapy to mucosal structures in this elderly female. Acute mucositis could impair nutrition, quality of life, and treatment intensity especially given her age. We compared 3 techniques that are appropriate for this target: step-and-shoot IMRT, matched electron fields (MEF), and electron conformal therapy (BolusECT™). We selected and treated her with BolusECT™ because of better sparing of larynx, pharynx, oral cavity and lips, and shortest treatment time. This is a reasonable option for treating ipsilateral head and neck target volumes at centers where only these 3 techniques are available.


Assuntos
Carcinoma de Célula de Merkel/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Mucosite/etiologia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/efeitos adversos , Idoso de 80 Anos ou mais , Carcinoma de Célula de Merkel/patologia , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Dosagem Radioterapêutica
8.
Int J Radiat Oncol Biol Phys ; 68(3): 719-30, 2007 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-17543999

RESUMO

PURPOSE: To determine the effects of three changes in radiotherapy technique on the outcomes for patients irradiated postoperatively for maxillary sinus cancer. METHODS AND MATERIALS: The data of 146 patients treated between 1969 and 2002 were reviewed. The patients were separated into two groups according to the date of treatment. Group 1 included 90 patients treated before 1991 and Group 2 included 56 patients treated after 1991, when the three changes were implemented. The outcomes were compared between the two groups. RESULTS: No differences were found in the 5-year overall survival, recurrence-free survival, local control, nodal control, or distant metastasis rates between the two groups (51% vs. 62%, 51% vs. 57%, 76% vs. 70%, 82% vs. 83%, and 28% vs. 17% for Groups 1 and 2, respectively). The three changes were to increase the portals to cover the base of the skull in patients with perineural invasion, reducing their risk of local recurrence; the addition of elective neck irradiation in patients with squamous or undifferentiated histologic features, improving the nodal control, distant metastasis, and recurrence-free survival rates (64% vs. 93%, 20% vs. 3%, and 45% vs. 67%, respectively; p < 0.05 for all comparisons); and improving the dose distributions within the target volume, reducing the late Grade 3-4 complication rates (34% in Group 1 vs. 8% in Group 2, p = 0.014). Multivariate analysis revealed advancing age, the need for enucleation, and positive margins as independent predictors of worse overall survival. The need for enucleation also predicted for worse local control. CONCLUSION: The three changes in radiotherapy technique improved the outcomes for select patients as predicted. Despite these changes, little demonstrable overall improvement occurred in local control or survival for these patients and additional work must be done.


Assuntos
Neoplasias do Seio Maxilar/mortalidade , Neoplasias do Seio Maxilar/radioterapia , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/prevenção & controle , Cuidados Pós-Operatórios/mortalidade , Lesões por Radiação/mortalidade , Medição de Risco/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Humanos , Incidência , Estudos Longitudinais , Masculino , Neoplasias do Seio Maxilar/cirurgia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/cirurgia , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida , Taxa de Sobrevida , Texas/epidemiologia , Resultado do Tratamento
9.
Int J Radiat Oncol Biol Phys ; 69(4): 1290-6, 2007 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-17967319

RESUMO

PURPOSE: To quantify the differences between planned and delivered parotid gland and target doses, and to assess the benefits of daily bone alignment for head and neck cancer patients treated with intensity-modulated radiotherapy (IMRT). METHODS AND MATERIALS: Eleven head and neck cancer patients received two CT scans per week with an in-room CT scanner over the course of their radiotherapy. The clinical IMRT plans, designed with 3-mm to 4-mm planning margins, were recalculated on the repeat CT images. The plans were aligned using the actual treatment isocenter marked with radiopaque markers (BB) and bone alignment to the cervical vertebrae to simulate image-guided setup. In-house deformable image registration software was used to map daily dose distributions to the original treatment plan and to calculate a cumulative delivered dose distribution for each patient. RESULTS: Using conventional BB alignment led to increases in the parotid gland mean dose above the planned dose by 5 to 7 Gy in 45% of the patients (median, 3.0 Gy ipsilateral, p = 0.026; median, 1.0 Gy contralateral, p = 0.016). Use of bone alignment led to reductions relative to BB alignment in 91% of patients (median, 2 Gy; range, 0.3-8.3 Gy; 15 of 22 parotids improved). However, the parotid dose from bone alignment was still greater than planned (median, 1.0 Gy, p = 0.007). Neither approach affected tumor dose coverage. CONCLUSIONS: With conventional BB alignment, the parotid gland mean dose was significantly increased above the planned mean dose. Using daily bone alignment reduced the parotid dose compared with BB alignment in almost all patients. A 3- to 4-mm planning margin was adequate for tumor dose coverage.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/radioterapia , Glândula Parótida , Radioterapia de Intensidade Modulada , Algoritmos , Vértebras Cervicais , Humanos , Movimento , Glândula Parótida/diagnóstico por imagem , Próteses e Implantes , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Medula Espinal/diagnóstico por imagem , Tomografia Computadorizada por Raios X
10.
Int J Radiat Oncol Biol Phys ; 68(5): 1512-21, 2007 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-17674982

RESUMO

PURPOSE: To determine whether a computer-assisted target volume delineation (CAT) system using a deformable image registration approach can reduce the variation of target delineation among physicians with different head and neck (HN) IMRT experiences and reduce the time spent on the contouring process. MATERIALS AND METHODS: We developed a deformable image registration method for mapping contours from a template case to a patient case with a similar tumor manifestation but different body configuration. Eight radiation oncologists with varying levels of clinical experience in HN IMRT performed target delineation on two HN cases, one with base-of-tongue (BOT) cancer and another with nasopharyngeal cancer (NPC), by first contouring from scratch and then by modifying the contours deformed by the CAT system. The gross target volumes were provided. Regions of interest for comparison included the clinical target volumes (CTVs) and normal organs. The volumetric and geometric variation of these regions of interest and the time spent on contouring were analyzed. RESULTS: We found that the variation in delineating CTVs from scratch among the physicians was significant, and that using the CAT system reduced volumetric variation and improved geometric consistency in both BOT and NPC cases. The average timesaving when using the CAT system was 26% to 29% for more experienced physicians and 38% to 47% for the less experienced ones. CONCLUSIONS: A computer-assisted target volume delineation approach, using a deformable image-registration method with template contours, was able to reduce the variation among physicians with different experiences in HN IMRT while saving contouring time.


Assuntos
Oncologia/normas , Neoplasias Nasofaríngeas/radioterapia , Planejamento da Radioterapia Assistida por Computador , Neoplasias da Língua/radioterapia , Eficiência , Humanos , Neoplasias Nasofaríngeas/diagnóstico por imagem , Radiografia , Neoplasias da Língua/diagnóstico por imagem , Carga Tumoral
11.
Int J Radiat Oncol Biol Phys ; 64(5): 1559-69, 2006 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-16580505

RESUMO

PURPOSE: To analyze three-dimensional setup uncertainties for multiple regions of interest (ROIs) in head-and-neck region. METHODS AND MATERIALS: In-room computed tomography (CT) scans were acquired using a CT-on-rails system for 14 patients. Three separate bony ROIs were defined: C2 and C6 vertebral bodies and the palatine process of the maxilla. Translational shifts of 3 ROIs were calculated relative to the marked isocenter on the immobilization mask. RESULTS: The shifts for all 3 ROIs were highly correlated. However, noticeable differences on the order of 2-6 mm existed between any 2 ROIs, indicating the flexibility and/or rotational effect in the head-and-neck region. The palatine process of the maxilla had the smallest right-left shifts because of the tight lateral fit in the face mask, but the largest superior-inferior movement because of in-plane rotation and variations in jaw positions. The neck region (C6) had the largest right-left shifts. The positioning mouthpiece was found effective in reducing variations in the superior-inferior direction. There was no statistically significant improvement for using the S-board (8 out of 14 patients) vs. the short face mask. CONCLUSIONS: We found variability in setup corrections for different regions of head-and-neck anatomy. These relative positional variations should be considered when making setup corrections or designing treatment margins.


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Movimento , Planejamento da Radioterapia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Fracionamento da Dose de Radiação , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador/métodos , Máscaras , Protetores Bucais , Radioterapia Conformacional/métodos , Restrição Física/instrumentação , Restrição Física/métodos , Rotação
12.
Int J Radiat Oncol Biol Phys ; 62(4): 1117-24, 2005 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-15990017

RESUMO

PURPOSE: To determine the influence of target-volume expansion on the reduction in small-bowel dose achieved with use of intensity-modulated radiation therapy (IMRT) vs. standard conformal treatment of the pelvis after hysterectomy, and to investigate the influence of patient body habitus on the normal-tissue sparing achieved with use of IMRT. METHODS AND MATERIALS: A clinical target volume (CTV) was contoured on each of 10 planning computed tomography scans of patients who had been treated for cervical or endometrial cancer after a hysterectomy. Treatment planning was based on vaginal CTVs and regional nodal CTVs. To account for internal motion, margins were added to form an initial planning target volume (PTVA) as follows: 0.0 mm were added to the regional nodal CTV; 10 mm were added anteriorly to the vaginal CTV; and 5 mm were added to the vaginal CTV in all other directions. Two further PTVs (PTVB and PTVC) were produced by a 5-mm expansion of PTVA to give PTVB and a further 5-mm expansion to give PTVC. Treatment plans for all 3 PTVs were produced by use of 2 conformal fields (2FC), 4 conformal fields (4FC), or IMRT to deliver 45 Gy to more than 97% of the PTV. The primary goal of IMRT was to spare small bowel. The change in sparing that accompanied the increase in margin size was assessed by comparison of dose-volume histograms that resulted from PTVA, PTVB, and PTVC. Measured patient dimensions were correlated with bowel sparing. RESULTS: Significantly less small bowel was irradiated by IMRT than by 2FC (p < 0.0001) or 4FC (p < 0.0001) for doses greater than 25 Gy. Significantly less rectum was irradiated by IMRT than by 2FC (p < 0.0001) or 4FC (p < 0.0001). Significantly less bladder was irradiated by IMRT than by 2FC (p < 0.0001). However, the magnitude of the sparing achieved by use of IMRT decreased as margins increased. In particular, the volume of small bowel spared by IMRT vs. 2FC or 4FC decreased as margin size increased (p = 0.0002 and p = 0.008 for 2FC and 4FC, respectively). The amount of normal-tissue sparing achieved by use of IMRT vs. 4FC was inversely correlated with patient body mass index. CONCLUSION: Because the small-bowel sparing achieved with use of IMRT is markedly reduced by relatively small expansions of the target volume, accurate target delineation, highly reproducible patient immobilization, and a clear understanding of internal-organ motion are needed to achieve optimal advantage in the use of IMRT over conventional methods of posthysterectomy pelvic radiation therapy.


Assuntos
Neoplasias do Endométrio/radioterapia , Intestino Delgado/efeitos da radiação , Lesões por Radiação/prevenção & controle , Radioterapia Conformacional/métodos , Neoplasias do Colo do Útero/radioterapia , Análise de Variância , Índice de Massa Corporal , Terapia Combinada , Neoplasias do Endométrio/cirurgia , Feminino , Humanos , Histerectomia , Movimento , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Reto/efeitos da radiação , Neoplasias do Colo do Útero/cirurgia
13.
Int J Radiat Oncol Biol Phys ; 63(2): 594-601, 2005 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-16168851

RESUMO

PURPOSE: To determine the effectiveness of noncoplanar beam configurations and the benefit of plans using fewer but optimally placed beams designed by a parallelized multiple-resolution beam angle optimization (PMBAO) approach. METHODS AND MATERIALS: The PMBAO approach uses a combination of coplanar and noncoplanar beam configurations for intensity-modulated radiation therapy (IMRT) treatment planning of paranasal sinus cancers. A smaller number of beams (e.g. 3) are first used to explore the solution space to determine the best and worst beam directions. The results of this exploration are then used as a starting point for determining an optimum beam orientation configuration with more beams (e.g. 5). This process is parallelized using a message passing interface, which greatly reduces the overall computation time for routine clinical practice. To test this approach, treatment for 10 patients with paranasal sinus cancer was planned using a total of 5 beams from a pool of 46 possible beam angles. The PMBAO treatment plans were also compared with IMRT plans designed using 9 equally spaced coplanar beams, which is the standard approach in our clinic. Plans with these two different beam configurations were compared with respect to dose conformity, dose heterogeneity, dose-volume histograms, and doses to organs at risk (i.e., eyes, optic nerve, optic chiasm, and brain). RESULTS: The noncoplanar beam configuration was superior in most paranasal sinus carcinoma cases. The target dose homogeneity was better using a PMBAO 5-beam configuration. However, the dose conformity using PMBAO was not improved and was case dependent. Compared with the 9-beam configuration, the PMBAO configuration significantly reduced the mean dose to the eyes and optic nerves and the maximum dose to the contralateral optical path (e.g. the contralateral eye and optic nerve). The maximum dose to the ipsilateral eye and optic nerve was also lower using the PMBAO configuration than using the 9-beam configuration, although this difference was not significant. The mean doses to the optic chiasm and brain are marginally lower using the PMBAO configuration than using 9-beam configuration. The maximum doses to the optic chiasm and brain are the same with the PMBAO configuration and the 9-beam configuration. CONCLUSION: Parallelized multiple-resolution beam angle optimization with an optimized noncoplanar beam configuration is an effective and practical approach for IMRT treatment planning. Five-beam treatment plans optimized using the PMBAO are at least equivalent to, and overall better than, the plans using 9 equally spaced coplanar beams.


Assuntos
Neoplasias dos Seios Paranasais/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Humanos , Neoplasias dos Seios Paranasais/diagnóstico por imagem , Radiografia , Dosagem Radioterapêutica
14.
Int J Radiat Oncol Biol Phys ; 61(4): 1062-70, 2005 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-15752885

RESUMO

PURPOSE: To evaluate retrospectively the utility of intensity-modulated radiotherapy (IMRT) in reducing the volume of normal tissues receiving radiation at varying dose levels when the female pelvis after hysterectomy is treated to doses of 50.4 Gy and 54 Gy. METHODS AND MATERIALS: Computed tomography scans from 10 patients who had previously undergone conventional postoperative RT were selected. The clinical tumor volume (vaginal apex and iliac nodes) and organs at risk were contoured. Margins were added to generate the planning tumor volume. The Pinnacle and Corvus planning systems were used to develop conventional and IMRT plans, respectively. Conventional four-field plans were prescribed to deliver 45 Gy (4F(45 Gy)) or 50.4 Gy; eight-field IMRT plans were prescribed to deliver 50.4 Gy (IMRT(50.4 Gy)) or 54 Gy (IMRT(54 Gy)) to the planning tumor volume. All plans were normalized so that > or =97% of the planning tumor volume received the prescribed dose. Student's t test was used to compare the volumes of organs at risk receiving the same doses with different plans. RESULTS: The mean volume of bowel receiving > or =45 Gy was lower with the IMRT(50.4 Gy) (33% lower) and IMRT(54 Gy) (18% lower) plans than with the 4F(45 Gy) plan. The mean volume of rectum receiving > or =45 Gy or > or =50 Gy was also significantly reduced with the IMRT plans despite an escalation of the prescribed dose from 45 Gy with the conventional plans to 54 Gy with IMRT. The mean volume of bladder treated to 45 Gy was the same or slightly lower with the IMRT(50.4 Gy) and IMRT(54 Gy) plans compared with the 4F(45 Gy) plan. Compared with the 4F(45 Gy) plan, the IMRT(50.4 Gy) plan resulted in a smaller volume of bowel receiving 35-45 Gy and a larger volume of bowel receiving 50-55 Gy. Compared with the 4F(45 Gy) plan, the IMRT(54 Gy) plan resulted in smaller volumes of bowel receiving 45-50 Gy; however, small volumes of bowel received 55-60 Gy with the IMRT plan. CONCLUSION: Intensity-modulated RT may permit an increase in the radiation dose that can safely be delivered to the central pelvis and pelvic lymph nodes after hysterectomy. However, dose-volume calculations using individual CT scans do not account for internal organ motion. Detailed data concerning the relationships among radiation dose, treatment volume, and treatment effects are lacking, and prospective studies of pelvic IMRT are needed to determine the safety and efficacy of this treatment.


Assuntos
Radioterapia Conformacional/métodos , Neoplasias do Colo do Útero/radioterapia , Estudos de Viabilidade , Feminino , Humanos , Histerectomia , Intestinos/diagnóstico por imagem , Intestinos/efeitos da radiação , Período Pós-Operatório , Dosagem Radioterapêutica , Reto/diagnóstico por imagem , Reto/efeitos da radiação , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Bexiga Urinária/diagnóstico por imagem , Bexiga Urinária/efeitos da radiação , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/cirurgia
15.
Int J Radiat Oncol Biol Phys ; 55(3): 768-75, 2003 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-12573764

RESUMO

PURPOSE: Malignant pleural mesothelioma (MPM) causes symptoms and death mainly due to local progression, even after combined modality treatment. Poor local control after conventional radiotherapy may be due to the low dose of radiation that has been administered or to restriction of the target volume to avoid critical organs. Intensity-modulated radiation therapy (IMRT) has the potential to overcome these geometric/dosimetric constraints. METHODS AND MATERIALS: Seven patients with MPM who had an extrapleural pneumonectomy (EPP) were treated with adjuvant IMRT. The clinical target volume (CTV) included the surgically violated area inside the chest wall with particular attention to the insertion of the diaphragm, pleural reflections, and the deep margin of the thoracotomy incision. Treatment was delivered by intensity-modulated 6-MV photon beams using dynamic multileaf collimation. RESULTS: The CTV ranged from 2667 to 7286 mL. The average CTV covered to 50 Gy was 94% (range, 92% to 98%). Respiratory motion was minimal. The average volume of the boost areas covered by 60 Gy was 92% (range, 82% to 99%). Dose-volume constraints for normal tissue were met in almost all cases. Acute toxicity was mild to moderate. The most severe side effects were anorexia, nausea or vomiting, and dyspnea. Esophagitis was absent or mild. After a minimum of 13 months follow-up care there were no cases of disease recurrence within the ipsilateral hemithorax. CONCLUSION: Treatment of the extensive operative area after an EPP is feasible using IMRT. Input from the radiologist and from the surgeon in the planning process facilitates definition of the high dose volumes. In light of patients' tolerance to post-EPP IMRT, it may be feasible to incorporate systemic therapy, including novel biologic therapies into the treatment regimen.


Assuntos
Mesotelioma/radioterapia , Neoplasias Pleurais/radioterapia , Lesões por Radiação/prevenção & controle , Radioterapia Conformacional/métodos , Idoso , Humanos , Imobilização , Masculino , Mesotelioma/patologia , Mesotelioma/cirurgia , Pessoa de Meia-Idade , Neoplasias Pleurais/patologia , Neoplasias Pleurais/cirurgia , Pneumonectomia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Adjuvante/métodos , Resultado do Tratamento
16.
Int J Radiat Oncol Biol Phys ; 55(3): 606-16, 2003 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-12573747

RESUMO

PURPOSE: New insight into the extent of the target volume for the postoperative irradiation of malignant pleural mesothelioma as determined during surgery has indicated that standard conformal radiotherapy (IMRT) is not sufficient for curative treatment. We describe a novel technique for implementing intensity-modulated radiotherapy (IMRT) to deliver higher doses to treat the full extent of these complex target volumes. METHODS AND MATERIALS: After extrapleural pneumonectomy, 7 patients underwent simulation, treatment planning, and treatment with IMRT to the involved hemithorax and adjacent abdomen. The target volumes encompassed the entire operative bed, including the ipsilateral mediastinum, anterior pleural reflection, and ipsilateral pericardium and the insertion of the diaphragm and crura. These were extensively marked during surgery with radiopaque markers to facilitate target delineation. RESULTS: Setup uncertainty and respiratory-dependent motion were found to be small. Coverage of the planning target volume was very good, with the crus of the diaphragm the most difficult volume to irradiate. The radiation doses to normal structures were acceptable. CONCLUSION: IMRT for treatment of malignant mesothelioma after extrapleural pneumonectomy results in more potentially curative doses to large, complex target volumes with acceptable doses to normal tissues.


Assuntos
Mesotelioma/radioterapia , Neoplasias Pleurais/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Humanos , Mesotelioma/diagnóstico por imagem , Mesotelioma/cirurgia , Imagens de Fantasmas , Projetos Piloto , Neoplasias Pleurais/diagnóstico por imagem , Neoplasias Pleurais/cirurgia , Pneumonectomia/métodos , Período Pós-Operatório , Doses de Radiação , Tomografia Computadorizada por Raios X , Resultado do Tratamento
17.
Int J Radiat Oncol Biol Phys ; 82(3): e367-74, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22284033

RESUMO

BACKGROUND: This analysis was undertaken to assess the need for planned neck dissection in patients with a complete response (CR) of involved nodes after irradiation and to determine the benefit of a neck dissection in those with less than CR by tumor site. METHODS: Our cohort included 880 patients with T1-4, N1-3M0 squamous cell carcinoma of the oropharynx, larynx, or hypopharynx who received treatment between 1994 and 2004. Survival curves were calculated by the Kaplan-Meier Method, comparisons of rates with the log-rank test and prognostic factors by Cox's proportional hazard model. RESULTS: Nodal CR occurred in 377 (43%) patients, of whom 365 patients did not undergo nodal dissection. The 5-year actuarial regional control rate of patients with CR was 92%. Two hundred sixty-eight of the remaining patients (53%) underwent neck dissections. The 5-year actuarial regional control rate for patients without a CR was 84%. Those who had a neck dissection fared better with 5-year actuarial regional control rates of 90% and 76% for those operated and those not operated (p < 0.001). Variables associated with poorer regional control rates included higher T and N stage, non-oropharynx cancers, non-CR, both clinical and pathological. CONCLUSIONS: With 92% 5-year neck control rate without neck dissection after CR, there is little justification for systematic neck dissection. The addition of a neck dissection resulted in higher neck control after partial response though patients with viable tumor on pathology specimens had poorer outcomes. The identification of that subgroup that benefits from additional treatment remains a challenge.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias Laríngeas/radioterapia , Esvaziamento Cervical , Neoplasias Faríngeas/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/secundário , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/cirurgia , Linfonodos/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Esvaziamento Cervical/métodos , Esvaziamento Cervical/estatística & dados numéricos , Neoplasia Residual , Neoplasias Faríngeas/patologia , Neoplasias Faríngeas/cirurgia , Indução de Remissão , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
18.
Int J Radiat Oncol Biol Phys ; 74(4): 1083-91, 2009 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-19095376

RESUMO

PURPOSE: To review institutional outcomes for patients treated for differentiated thyroid cancer with postoperative conformal external beam radiotherapy (EBRT). METHODS AND MATERIALS: This is a single-institution retrospective review of 131 consecutive patients with differentiated thyroid cancer who underwent EBRT between January 1996 and December 2005. Histologic diagnoses included 104 papillary, 21 follicular, and six mixed papillary-follicular types. American Joint Committee on Cancer stage distribution was Stage III in 2 patients, Stage IVa-IVc in 128, and not assessable in 1. Thirty-four patients (26%) had high-risk histologic types and 76 (58%) had recurrent disease. Extraglandular disease spread was seen in 126 patients (96%), microscopically positive surgical margins were seen in 62 patients (47%), and gross residual disease was seen in 15 patients (11%). Median EBRT dose was 60 Gy (range, 38-72 Gy). Fifty-seven patients (44%) were treated with intensity-modulated radiotherapy (IMRT) to a median dose of 60 Gy (range, 56-66 Gy). Median follow-up was 38 months (range, 0-134 months). RESULTS: Kaplan-Meier estimates of locoregional relapse-free survival, disease-specific survival, and overall survival at 4 years were 79%, 76%, and 73%, respectively. On multivariate analysis, high-risk histologic features and gross residual disease predicted for inferior locoregional relapse-free survival, whereas high-risk histologic features, M1 disease, and gross residual disease predicted for inferior disease-specific and overall survival. The IMRT did not impact on survival outcomes, but was associated with less frequent severe late morbidity (12% vs. 2%). CONCLUSIONS: Postoperative conformal EBRT provides durable locoregional disease control for patients with high-risk differentiated thyroid cancer if disease is reduced to microscopic burden. Patients with gross disease face significantly worse outcomes. The IMRT may significantly reduce chronic radiation morbidity, but requires additional study.


Assuntos
Adenocarcinoma Folicular/radioterapia , Carcinoma Papilar/radioterapia , Radioterapia de Intensidade Modulada , Neoplasias da Glândula Tireoide/radioterapia , Adenocarcinoma Folicular/mortalidade , Adenocarcinoma Folicular/patologia , Adenocarcinoma Folicular/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Papilar/mortalidade , Carcinoma Papilar/patologia , Carcinoma Papilar/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia , Neoplasia Residual , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/efeitos adversos , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/mortalidade , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Adulto Jovem
19.
Int J Radiat Oncol Biol Phys ; 73(2): 399-409, 2009 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-18556144

RESUMO

PURPOSE: Institutional and cooperative group experience has demonstrated the feasibility of reirradiation for head and neck cancer. Limited data are available regarding the use of intensity-modulated radiotherapy (IMRT) for this indication. We reviewed our initial experience using IMRT for previously irradiated head and neck cancer patients. METHODS AND MATERIALS: Records of 78 consecutive patients reirradiated with IMRT for head and neck cancer between 1999 and 2004 were reviewed; 74 cases were analyzed. Reirradiation was defined as any overlap between original and new radiation treatment volumes regardless of the time interval between initial and subsequent treatment. Severe reirradiation-related toxicity was defined as toxic events resulting in hospitalization, corrective surgery, or patient death. Longitudinal estimates of survival were calculated by Kaplan-Meier technique. RESULTS: Twenty (27%) patients underwent salvage surgical resection and 36 (49%) patients received chemotherapy. Median follow-up from reirradiation was 25 months. Median time interval between initial radiation and reirradiation was 46 months. Median reirradiation dose was 60 Gy. Median lifetime radiation dose was 116.1 Gy. The 2-year overall survival and locoregional control rates were 58% and 64%, respectively. Severe reirradiation related toxicity occurred in 15 patients (20%); one treatment-related death was observed. CONCLUSIONS: The use of IMRT for reirradiation of recurrent or second primary head and neck cancers resulted in encouraging local control and survival. Reirradiation-related morbidity was significant, but may be less severe than previously published reports using conventional techniques.


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Recidiva Local de Neoplasia/radioterapia , Segunda Neoplasia Primária/radioterapia , Radioterapia de Intensidade Modulada , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirurgia , Feminino , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/cirurgia , Segunda Neoplasia Primária/tratamento farmacológico , Segunda Neoplasia Primária/cirurgia , Doses de Radiação , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Radioterapia de Intensidade Modulada/mortalidade , Retratamento/efeitos adversos , Estudos Retrospectivos , Terapia de Salvação , Adulto Jovem
20.
Cancer ; 112(12): 2698-709, 2008 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18429002

RESUMO

BACKGROUND: Basaloid squamous cell carcinoma (BSCC) is an uncommon, high-grade variant of squamous cell carcinoma (SCC) of the head and neck. Its poorer prognosis compared with common SCC remains controversial. The authors investigated the outcomes of patients with BSCC who received radiotherapy and compared them with the outcomes of patients with SCC. METHODS: From 1994 to 2004, 1007 patients received radiotherapy for head and neck carcinoma with lymph node involvement. The histologic types consisted of 51 BSCC, 431 poorly differentiated SCC (PSCC), and 525 well or moderately differentiated SCC (WMSCC). A case-control analysis was performed with BSCC matched against both PSCC and WMSCC to compare disease-control and survival rates. RESULTS: Patients with BSCC received treatment modalities similar to those received by patients with SCC: They received induction chemotherapy (12%) or concurrent chemotherapy (33%), and a median radiation dose of 70 Gray. Posttreatment viable tumor was present in 44%, 13%, and 28% of neck dissection specimens from patients with BSCC, PSCC, and WMSCC, respectively. The 5-year disease-free survival rates (63%, 77%, and 76%, respectively) and overall survival rates (85%, 70%, and 71%, respectively) demonstrated no statistically significant differences for BSCC, PSCC, or WMSCC, respectively. CONCLUSIONS: In this study, a poorer prognosis could not be demonstrated for irradiated patients with BSCC compared with either PSCC or WMSCC. All patients in this study had positive lymph node status, and the majority of patients (84%) had oropharyngeal cancer. The BSCC cohort did have a relatively high rate of viable tumor in their posttreatment neck dissections, and they had a relatively high rate of distant disease. On the basis of the high rate of lung metastases and the possibility of efficient salvage, the authors recommend obtaining a chest computed tomography scan during initial staging and follow-up.


Assuntos
Carcinoma Basoescamoso/radioterapia , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Adulto , Idoso , Estudos de Casos e Controles , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Esvaziamento Cervical , Recidiva Local de Neoplasia , Prognóstico , Dosagem Radioterapêutica , Taxa de Sobrevida
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