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PURPOSE: More than 6,500 megavoltage teletherapy units are needed worldwide, many in low-resource settings. Cobalt-60 units or linear accelerators (linacs) can fill this need. We have evaluated machine performance on the basis of patient throughput to provide insight into machine viability under various conditions in such a way that conclusions can be generalized to a vast array of clinical scenarios. MATERIALS AND METHODS: Data from patient treatment plans, peer-reviewed studies, and international organizations were combined to assess the relative patient throughput of linacs and cobalt-60 units that deliver radiotherapy with standard techniques under various power and maintenance support conditions. Data concerning the frequency and duration of power outages and downtime characteristics of the machines were used to model teletherapy operation in low-resource settings. RESULTS: Modeled average daily throughput was decreased for linacs because of lack of power infrastructure and for cobalt-60 units because of limited and decaying source strength. For conformal radiotherapy delivered with multileaf collimators, average daily patient throughput over 8 years of operation was equal for cobalt-60 units and linacs when an average of 1.83 hours of power outage occurred per 10-hour working day. Relative to conformal treatments delivered with multileaf collimators on the respective machines, the use of advanced techniques on linacs decreased throughput between 20% and 32% and, for cobalt machines, the need to manually place blocks reduced throughput up to 37%. CONCLUSION: Our patient throughput data indicate that cobalt-60 units are generally best suited for implementation when machine operation might be 70% or less of total operable time because of power outages or mechanical repair. However, each implementation scenario is unique and requires consideration of all variables affecting implementation.
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BACKGROUND: To meet demand for radiation oncology services and ensure patient-centered safe care, management in an academic radiation oncology department initiated quality improvement efforts using discrete-event simulation (DES). Although the long-term goal was testing and deploying solutions, the primary aim at the outset was characterizing and validating a computer simulation model of existing operations to identify targets for improvement. METHODS: The adoption and validation of a DES model of processes and procedures affecting patient flow and satisfaction, employee experience, and efficiency were undertaken in 2012-2013. Multiple sources were tapped for data, including direct observation, equipment logs, timekeeping, and electronic health records. RESULTS: During their treatment visits, patients averaged 50.4 minutes in the treatment center, of which 38% was spent in the treatment room. Patients with appointments between 10 AM and 2 PM experienced the longest delays before entering the treatment room, and those in the clinic in the day's first and last hours, the shortest (<5 minutes). Despite staffed for 14.5 hours daily, the clinic registered only 20% of patients after 2:30 PM. Utilization of equipment averaged 58%, and utilization of staff, 56%. CONCLUSION: The DES modeling quantified operations, identifying evidence-based targets for next-phase remediation and providing data to justify initiatives.
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Instituciones Oncológicas/organización & administración , Eficiencia Organizacional , Mejoramiento de la Calidad , Oncología por Radiación , Instituciones de Atención Ambulatoria , Citas y Horarios , Simulación por Computador , Registros Electrónicos de Salud , Humanos , Reproducibilidad de los Resultados , Asignación de Recursos , TiempoRESUMEN
PURPOSE: Academic centers increasingly find a need to define a comprehensive peer-review program that can translate high-quality radiation therapy (RT) to community network sites. In this study, we describe the initial results of a quarterly quality audit program that aims to improve RT peer-review and provider educational processes across community sites. MATERIALS AND METHODS: An electronic tool was used by community-based certified member (CM) sites to enter clinical treatment information about patients undergoing peer review. At least 10% of the patient load for each CM physician was selected for audit on a quarterly basis by expert academic faculty. Quality metrics included the review of the management plan, technical plan, and other indicators. RT was scored as being concordant or nonconcordant with institutional guidelines, national standards, or expert judgment. RESULTS: A total of 719 patients were entered into the peer-review database by the first four CM sites. Of 14% of patients audited, 17% (18 of 104) were deemed nonconcordant. Nonconcordance rates were lowest in prevalent disease sites, such as breast (16%), colorectal (14%), and lung (12%), whereas rates were highest in lymphoma (50%), brain (44%), and gynecology (27%). Deficiencies included incomplete staging work-up, incorrect target and normal tissue delineation, and nonadherence to accepted dose-volume constraints. CONCLUSION: Given the high rate of nonconcordance, we recommend prospective, pre-RT peer review of all patients, and, in particular, expert review of patients that are from low-volume or complex disease sites. An integrated approach to peer review holds a promise of improving the quality, safety, and value of cancer therapy in the community setting.
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Centros Médicos Académicos/normas , Instituciones Oncológicas/normas , Revisión por Expertos de la Atención de Salud , Calidad de la Atención de Salud , Oncología por Radiación/normas , Humanos , Auditoría Médica/métodos , Revisión por Expertos de la Atención de Salud/métodosRESUMEN
PURPOSE: To evaluate the correlations and relative contributions of components of a radiation oncology-specific patient satisfaction survey to their overall satisfaction scores. METHODS AND MATERIALS: From September 2006 through August 2012, we prospectively collected data from 8069 patients receiving radiation treatments with a 26-question survey. Each question was rated on a 10-point Likert scale. We analyzed the correlation between scores for each question and the overall satisfaction question. We also dichotomized the scores to reflect satisfaction versus dissatisfaction and used logistic regression to assess the relationship between items in 4 domains (the patient-provider relationship, access and environmental issues, wait times, and educational information) and overall satisfaction. RESULTS: Scores on all questions correlated with overall patient satisfaction scores (P<.0001). Satisfaction with patient-provider relationships had the greatest influence on overall satisfaction (R(2)=0.4219), followed by wait times (R(2)=0.4000), access/environment (R(2)=0.3837), and patient education (R(2)=0.3700). The specific variables with the greatest effect on patient satisfaction were the care provided by radiation therapists (odds ratio 1.91) and pain management (odds ratio 1.29). CONCLUSIONS: We found that patients' judgment of provider relationships in an outpatient radiation oncology setting were the greatest contributors to their overall satisfaction ratings. Other measures typically associated with patient satisfaction (phone access, scheduling, and ease of the check-in process) correlated less strongly with overall satisfaction. These findings may be useful for other practices preparing to assess patient ratings of quality of care.
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Neoplasias/radioterapia , Satisfacción del Paciente , Relaciones Profesional-Paciente , Cuidados Posteriores , Recolección de Datos , Humanos , Neoplasias/psicología , Atención de Enfermería , Manejo del Dolor , Grupo de Atención al Paciente , Oncología por RadiaciónRESUMEN
PURPOSE: To evaluate the spatial relationship between peritumoral edema and recurrence pattern in patients with glioblastoma (GBM). METHODS AND MATERIALS: Forty-eight primary GBM patients received three-dimensional conformal radiotherapy that did not intentionally include peritumoral edema within the clinical target volume between July 2000 and June 2001. All 48 patients have subsequently recurred, and their original treatment planning parameters were used for this study. New theoretical radiation treatment plans were created for the same 48 patients, based on Radiation Therapy Oncology Group (RTOG) target delineation guidelines that specify inclusion of peritumoral edema. Target volume and recurrent tumor coverage, as well as percent volume of normal brain irradiated, were assessed for both methods of target delineation using dose-volume histograms. RESULTS: A comparison between the location of recurrent tumor and peritumoral edema volumes from all 48 cases failed to show correlation by linear regression modeling (r(2) = 0.0007; p = 0.3). For patients with edema >75 cm(3), the percent volume of brain irradiated to 46 Gy was significantly greater in treatment plans that intentionally included peritumoral edema compared with those that did not (38% vs. 31%; p = 0.003). The pattern of failure was identical between the two sets of plans (40 central, 3 in-field, 3 marginal, and 2 distant recurrence). CONCLUSION: Clinical target volume delineation based on a 2-cm margin rather than on peritumoral edema did not seem to alter the central pattern of failure for patients with GBM. For patients with peritumoral edema >75 cm(3), using a constant 2-cm margin resulted in a smaller median percent volume of brain being irradiated to 30 Gy, 46 Gy, and 50 Gy compared with corresponding theoretical RTOG plans that deliberately included peritumoral edema.
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Edema Encefálico/radioterapia , Neoplasias Encefálicas/radioterapia , Encéfalo , Glioblastoma/radioterapia , Recurrencia Local de Neoplasia/radioterapia , Radioterapia Conformacional/métodos , Adulto , Anciano , Edema Encefálico/etiología , Neoplasias Encefálicas/mortalidad , Distribución de Chi-Cuadrado , Glioblastoma/mortalidad , Humanos , Modelos Lineales , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Guías de Práctica Clínica como Asunto , Planificación de la Radioterapia Asistida por Computador/métodos , Sobrevida , Insuficiencia del TratamientoRESUMEN
PURPOSE: To determine and analyze the dosimetric consequences of current portal imaging practices for pediatric patients, and make specific recommendations for reducing exposure from portal imaging procedures. METHODS AND MATERIALS: A survey was sent to approximately 250 Children's Oncology Group (COG) member institutions asking a series of questions about their portal imaging practices. Three case studies are presented with dosimetric analysis to illustrate the magnitude of unintended dose received by nontarget tissues using the most common techniques from the survey. RESULTS: The vast majority of centers use double-exposure portal image techniques with a variety of open field margins. Only 17% of portal images were obtained during treatment, and for other imaging methods, few centers subtract monitor units from the treatment delivery. The number of monitor units used was nearly the same regardless of imager type, including electronic portal imaging devices. Eighty-six percent imaged all fields the first week and 17% imaged all fields every week. An additional 1,112 cm3 of nontarget tissue received 1 Gy in one of the example cases. Eight new recommendations are made, which will lower nontarget radiation doses with minimal impact on treatment verification accuracy. CONCLUSION: Based on the survey, changes can be made in portal imaging practices that will lower nontarget doses. It is anticipated that treatment verification accuracy will be minimally affected. Specific recommendations made to decrease the imaging dose and help lower the rate of radiation-induced secondary cancers in children are proposed for inclusion in future COG protocols using radiation therapy.
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Neoplasias/diagnóstico por imagen , Protección Radiológica/métodos , Radiometría/métodos , Encuestas y Cuestionarios , Tecnología Radiológica/métodos , Adolescente , Calibración , Niño , Femenino , Humanos , Masculino , Neoplasias/radioterapia , Oncología por Radiación/normas , Protección Radiológica/normas , Radiometría/normas , Dosificación Radioterapéutica , Tecnología Radiológica/normas , Tomografía Computarizada por Rayos X/métodos , Película para Rayos XRESUMEN
PURPOSE: To calculate treatment plans and compare the dose distributions and dose-volume histograms (DVHs) for photon three-dimensional conformal radiation therapy (3D-CRT), electron therapy, intensity-modulated radiation therapy (IMRT), and standard (nonintensity modulated) proton therapy in three pediatric disease sites. METHODS AND MATERIALS: The tumor volumes from 8 patients (3 retinoblastomas, 2 medulloblastomas, and 3 pelvic sarcomas) were studied retrospectively to compare DVHs from proton therapy with 3D-CRT, electron therapy, and IMRT. In retinoblastoma, several planning techniques were analyzed: A single electron appositional beam was compared with a single 3D-CRT lateral beam, a 3D-CRT anterior beam paired with a lateral beam, IMRT, and protons. In medulloblastoma, three posterior fossa irradiation techniques were analyzed: 3D-CRT, IMRT, and protons. Craniospinal irradiation (which consisted of composite plans of both the posterior fossa and craniospinal components) was also evaluated, primarily comparing spinal irradiation using 3D-CRT electrons, 3D-CRT photons, and protons. Lastly, in pelvic sarcoma, 3D-CRT, IMRT, and proton plans were assessed. RESULTS: In retinoblastoma, protons resulted in the best target coverage combined with the most orbital bone sparing (10% was the mean orbital bone volume irradiated at > or =5 Gy for protons vs. 25% for 3D-CRT electrons, 69% for IMRT, 41% for a single 3D lateral beam, 51% for a 3D anterolateral beam with a lens block, and 65% for a 3D anterolateral beam without a lens block). A single appositional electron field was the next best technique followed by other planning approaches. In medulloblastoma, for posterior fossa and craniospinal irradiation, protons resulted in the least dose to the cochlea (for only posterior fossa irradiation at > or =20 Gy, 34% was the mean cochlear volume irradiated for protons, 87% for IMRT, 89% for 3D-CRT) and hypothalamus-pituitary axis (for only posterior fossa irradiation at > or =10 Gy, 21% was the mean hypothalamus-pituitary volume irradiated for protons, 81% for IMRT, 91% for 3D-CRT); additional dose reductions to the optic chiasm, eyes, vertebrae, mandible, thyroid, lung, kidneys, heart, and liver were seen. Intensity-modulated radiotherapy appeared to be the second best technique for posterior fossa irradiation. For spinal irradiation 3D-CRT electrons were better than 3D-CRT photons in sparing dose to the thyroid, heart, lung, kidney, and liver. With pelvic sarcoma, protons were superior in eliminating any dose to the ovaries (0% of mean ovarian volume was irradiated at > or =2 Gy with protons) and to some extent, the pelvic bones and vertebrae. Intensity-modulated radiotherapy did show more bladder dose reduction than the other techniques in pelvic sarcoma irradiation. CONCLUSIONS: In the diseases studied, using various techniques of 3D-CRT, electrons, IMRT, and protons, protons are most optimal in treating retinoblastomas, medulloblastomas (posterior fossa and craniospinal), and pelvic sarcomas. Protons delivered superior target dose coverage and sparing of normal structures. As dose-volume parameters are expected to correlate with acute and late toxicity, proton therapy should receive serious consideration as the preferred technique for the treatment of pediatric tumors.
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Neoplasias Óseas/radioterapia , Neoplasias Cerebelosas/radioterapia , Meduloblastoma/radioterapia , Osteosarcoma/radioterapia , Huesos Pélvicos , Radioterapia Conformacional/métodos , Neoplasias de la Retina/radioterapia , Retinoblastoma/radioterapia , Adolescente , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Cerebelosas/diagnóstico por imagen , Niño , Preescolar , Electrones/uso terapéutico , Femenino , Humanos , Lactante , Masculino , Meduloblastoma/diagnóstico por imagen , Osteosarcoma/diagnóstico por imagen , Terapia de Protones , Traumatismos por Radiación/prevención & control , Radiografía , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador , Neoplasias de la Retina/diagnóstico por imagen , Retinoblastoma/diagnóstico por imagen , Estudios RetrospectivosRESUMEN
PURPOSE: Recently, considerable attention has been directed toward computed tomography radiation doses (estimated 1 to 4 cGy) received by pediatric patients, because of the potential for increasing a pediatric patient's risk for developing a secondary malignancy. However, minimal attention has been given to the radiation exposure outside the treatment field resulting from the use of portal films to visualize surrounding anatomy. The objective of this study was to quantify the radiation dose from portal imaging delivered within and outside the radiation treatment field during a course of radiation therapy. METHODS AND MATERIALS: A retrospective review was conducted of the port film dose for 56 consecutive pediatric patients who underwent definitive radiation therapy between January 2001 and January 2002. Treatment locations were classified as brain, 27 patients; abdomen, 11 patients; extremities, 9 patients; pelvis, 6 patients; and thorax, 3 patients. Using the dose per monitor unit and total number of port films taken, the total port film dose for each patient was calculated. In addition, port film dose was quantified for 5 pediatric patients undergoing intensity modulated radiation therapy. RESULTS: The mean total port dose varied from a maximum of 46 cGy for brain to a minimum of 17 cGy for thorax. The mean total port dose as a percentage of prescribed dose was less than 1.25% for all locations in this study; however, most of the port dose is a result of the open-field dose from the double-exposure technique. CONCLUSIONS: Care should be exercised while exposing port films of pediatric patients to minimize both the number of films and corresponding radiation exposure without compromising the quality of treatment delivery. Specifically, the number of monitor units used to image regions outside the treatment field should be kept to a minimum, because such exposure could lead to an increased risk of development of secondary neoplasms.
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Neoplasias/diagnóstico por imagen , Dosis de Radiación , Adolescente , Niño , Preescolar , Humanos , Lactante , Neoplasias/radioterapia , Neoplasias Inducidas por Radiación/prevención & control , Neoplasias Primarias Secundarias/prevención & control , Radiografía , Estudios RetrospectivosRESUMEN
Clinical trials often require homogeneous treatment plans. Many institutions, however, have begun using heterogeneous plans. Is it possible to satisfy the requirements of such a protocol while achieving the superior accuracy of heterogeneous treatment planning? At the University of Texas M. D. Anderson Cancer Center, we currently use conformal treatment planning with heterogeneities for thoracic cancers. This paper describes a procedure that has been developed to satisfy the requirements of a homogeneous protocol, such as RTOG 98-01 (A Phase III Study of Amifostine mucosal protection), while maintaining accuracy in treatment planning.