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1.
Phys Med Biol ; 58(12): 4013-29, 2013 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-23685807

RESUMEN

An objective method for establishing patient prioritization in the context of a radiotherapy waiting list is investigated. This is based on a utilitarian objective, being the greatest probability of local tumour control in the population of patients. A numerical simulation is developed and a clinical patient case-mix is used to determine the influence of the characteristics of the patient population on resulting optimal patient scheduling. With the utilitarian objective, large gains in tumour control probability (TCP) can be achieved for individuals or cohorts by prioritizing patients for that fraction of the patient population with relatively small sacrifices in TCP for a smaller fraction of the population. For a waiting list in steady state with five patients per day commencing treatment and leaving the list (and so with five patients per day entering the list), and a mean wait time of 35 days and a maximum of 90 days, optimized wait times ranged from a mean of one day for patients with tumour types with short effective doubling times to a mean of 66.9 days for prostate cancer patients. It is found that, when seeking the optimal daily order of patients on the waiting list in a constrained simulation, the relative rather than absolute value of TCP is the determinant of the resulting optimal waiting times. An increase in the mean waiting time mostly influences (increases) the optimal waiting times of patients with fast-growing tumours. The proportional representation of groups (separated by tumour type) in the patient population has an influence on the resulting distribution of optimal waiting times for patients in those groups, though has only a minor influence on the optimal mean waiting time for each group.


Asunto(s)
Neoplasias/radioterapia , Oncología por Radiación , Radioterapia/estadística & datos numéricos , Humanos , Modelos Estadísticos , Probabilidad , Factores de Tiempo , Listas de Espera
2.
Br J Cancer ; 106(1): 61-9, 2012 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-22134511

RESUMEN

BACKGROUND: Locally advanced inoperable pancreatic cancer (LAPC) has a poor prognosis. By increasing intensity of systemic therapy combined with an established safe chemoradiation technique, our intention was to enhance the outcomes of LAPC. In preparation for phase III evaluation, the feasibility and efficacy of our candidate regimen gemcitabine-oxaliplatin chemotherapy with sandwich 5-fluorouracil (5FU) and three-dimensional conformal radiotherapy (3DCRT) needs to be established. METHODS: A total of 48 patients with inoperable LAPC without metastases were given gemcitabine (1000 mg m(-2) d1 + d15 q28) and oxaliplatin (100 mg m(-2) d2 + d16 q28) in induction (one cycle) and consolidation (three cycles), and 5FU 200 mg m(-2) per day over 6 weeks during 3DCRT 54 Gy. RESULTS: Median duration of sustained local control (LC) was 15.8 months, progression-free survival (PFS) was 11.0 months, and overall survival was 15.7 months. Survival rates for 1, 2, and 3 years were 70.2%, 21.3%, and 12.8%, respectively. Global quality of life did not significantly decline from baseline during treatment, which was associated with modest treatment-related toxicity. CONCLUSION: Fixed-dose gemcitabine and oxaliplatin, combined with an effective and safe regimen of 5FU and 3DCRT radiotherapy, was feasible and reasonably tolerated. The observed improved duration of LC and PFS with more intensive therapy over previous trials may be due to patient selection, but suggest that further evaluation in phase III trials is warranted.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Pancreáticas/terapia , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Biomarcadores de Tumor/sangre , Antígeno CA-19-9/sangre , Terapia Combinada , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Femenino , Fluorouracilo/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Compuestos Organoplatinos/administración & dosificación , Oxaliplatino , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/radioterapia , Calidad de Vida , Resultado del Tratamiento , Gemcitabina
3.
J Med Imaging Radiat Oncol ; 54(2): 146-51, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20518879

RESUMEN

Multidisciplinary meetings (MDMs) are a useful aid for the development of comprehensive treatment plans for cancer patients. However, little is known about the requirements for effective MDM function. Attendees at a national lung cancer conference who participated at least weekly in lung cancer MDMs were surveyed. The survey addressed the attendees' perceptions regarding the aims of MDMs, and for their own institutional MDMs, the importance and need for improvement for each of: (i) the attendance of nine discipline groups; and (ii) 15 aspects related to MDM function derived from the literature. The survey also asked participants if MDMs met their needs. There was a general agreement on the aims of the meetings. There was also an agreement on the importance of various groups' attendance and each of the examined aspects of MDMs. However, many respondents reported their meetings required moderate or substantial improvements in one or more areas. More than 20% of the respondents indicated improvement was required for the attendance of three discipline groups (palliative care physicians, pathologists and cardiothoracic surgeons) and 10 of the 15 examined aspects (more than half in the case of computerised databases). Only 9% of the respondents reported that none of the features surveyed needed either moderate or substantial improvement. MDMs met the needs of 79% of the respondents. We found general agreement on the aims of the meetings, the importance of various groups' attendance at MDMs and each of the examined aspects of MDMs. However, moderate or substantial improvements were thought to be required by many respondents. The performance of individual institutions' MDMs and the resources they have available to achieve their aims should be assessed and periodically reviewed. The survey applied here may provide a framework for MDM members to do this.


Asunto(s)
Actitud del Personal de Salud , Procesos de Grupo , Comunicación Interdisciplinaria , Australia , Congresos como Asunto , Recolección de Datos
4.
Phys Med Biol ; 55(11): N337-46, 2010 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-20463378

RESUMEN

This study examined the variation of dose-volume histogram (DVH) data sourced from multiple radiotherapy treatment planning systems (TPSs). Treatment plan exports were obtained from 33 Australian and New Zealand centres during a dosimetry study. Plan information, including DVH data, was exported from the TPS at each centre and reviewed in a digital review system (SWAN). The review system was then used to produce an independent calculation of DVH information for each delineated structure. The relationships between DVHs extracted from each TPS and independently calculated were examined, particularly in terms of the influence of CT scan slice and pixel widths, the resolution of dose calculation grids and the TPS manufacturer. Calculation of total volume and DVH data was consistent between SWAN and each TPS, with the small discrepancies found tending to increase with decreasing structure size. This was significantly influenced by the TPS model used to derive the data. For target structures covered with relatively uniform dose distributions, there was a significant difference between the minimum dose in each TPS-exported DVH and that calculated independently.


Asunto(s)
Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia/métodos , Radioterapia/normas , Australia , Humanos , Modelos Estadísticos , Nueva Zelanda , Radiometría/métodos , Dosificación Radioterapéutica , Análisis de Regresión , Reproducibilidad de los Resultados , Tomografía Computarizada por Rayos X/métodos
5.
J Med Imaging Radiat Oncol ; 53(1): 87-91, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19453533

RESUMEN

Kasabach-Merritt syndrome involves thrombocytopenia, which is usually severe, in association with haemangiomata. We describe two newborn infants who developed life-threatening Kasabach-Merritt syndrome but who were successfully treated. Both had failed to respond adequately to corticosteroids and alpha-interferon. They subsequently received emergency radiotherapy. Both patients had an improvement in their platelet counts. The first infant's haemangioma gradually faded during the first 3 years of life, whereas the second infant's haemangioma had resolved 2 months after radiotherapy. No significant late effects of the radiotherapy have been noted at the 8 and 5 years follow up respectively. Radiotherapy remains an important treatment method in Kasabach-Merritt syndrome when patients fail to respond to other treatments.


Asunto(s)
Hemangioma/diagnóstico , Hemangioma/radioterapia , Trombocitopenia Neonatal Aloinmune/diagnóstico , Trombocitopenia Neonatal Aloinmune/radioterapia , Enfermedad Catastrófica/terapia , Hemangioma/congénito , Humanos , Recién Nacido , Masculino , Síndrome , Resultado del Tratamiento
6.
Intern Med J ; 39(12): 838-41, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20233244

RESUMEN

Abstract Patients with inoperable non-small cell lung cancer diagnosed and managed at a single institution over a one-year period were identified. Those whose case had been discussed at a multidisciplinary meeting had better survival than those whose case was not discussed (mean survival; 280 days vs. 205 days, log-rank P= 0.048).


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/terapia , Comunicación Interdisciplinaria , Neoplasias Pulmonares/terapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis de Supervivencia
8.
J Med Imaging Radiat Oncol ; 52(6): 605-10, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19178637

RESUMEN

Trainee radiation oncologists must master a substantial body of skills and knowledge to become competent specialists. The resources available to support this are limited. We surveyed the 90 registrars enrolled in the Royal Australian and New Zealand College of Surgeons (RANZCR) radiation oncology training programme to obtain a range of information about their learning activities (with a significant focus on part 1 teaching). Responses were received from 59 registrars (66% of those eligible). Trainees reported spending a median 2.5 h per week (range 0-10 h) in formal teaching activities. With regard to part 1 exam preparation, 83% reported having had physics teaching--the median quality was 5/7; 88% had radiobiology teaching--the median quality was 4/7; 52% had anatomy teaching--the median quality was 3/7. Registrars training within the RANZCR radiation oncologists training programme perceive their own clinical learning environment as generally good; however' 50% of respondents felt that more teaching was needed for part 1 subjects. This compared with only 19% of respondents who felt that more teaching was required for part 2 exam preparation. Innovative solutions, such as centralized web-based teaching, may help to address weaknesses in part 1 teaching. With increasing demands on radiation oncologists and trainees it will be important to monitor learning environments.


Asunto(s)
Internado y Residencia/estadística & datos numéricos , Internado y Residencia/tendencias , Médicos/estadística & datos numéricos , Médicos/tendencias , Oncología por Radiación/educación , Oncología por Radiación/estadística & datos numéricos , Estudiantes de Medicina/estadística & datos numéricos , Curriculum , Nueva Zelanda , Oncología por Radiación/organización & administración , Oncología por Radiación/tendencias , Singapur
9.
J Med Imaging Radiat Oncol ; 52(6): 598-604, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19178636

RESUMEN

Before a multicentre trial of 3-D conformal radiotherapy to treat cancer of the pancreas, participating clinicians were asked to complete an accreditation exercise. This involved planning two test cases according to the study protocol, then returning hard copies of the plans and dosimetric data for review. Any radiation technique that achieved the specified constraints was allowed. Eighteen treatment plans were assessed. Seven plans were prescribed incorrect doses and two of the planning target volumes did not comply with protocol guidelines. All plans met predefined normal tissue dose constraints. The identified errors were attributable to unforeseen ambiguities in protocol documentation. They were addressed by feedback and corresponding amendments to protocol documentation. Summary radiobiological measures including total weighted normal tissue equivalent uniform dose varied significantly between centres. This accreditation exercise successfully identified significant potential sources of protocol violations, which were then easily corrected. We believe that this process should be applied to all clinical trials involving radiotherapy. Due to the limitations of data analysis with hard-copy information only, it is recommended that complete planning datasets from treatment-planning systems be collected through a digital submission process.


Asunto(s)
Acreditación/normas , Antineoplásicos/uso terapéutico , Adhesión a Directriz/estadística & datos numéricos , Neoplasias Pancreáticas/terapia , Guías de Práctica Clínica como Asunto , Garantía de la Calidad de Atención de Salud/normas , Radioterapia Conformacional/normas , Australia , Humanos , Radioterapia Conformacional/estadística & datos numéricos
10.
J Med Imaging Radiat Oncol ; 52(6): 611-6, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19178638

RESUMEN

Accurate and reproducible patient positioning is fundamental to the success of fractionated radiotherapy. Poor patient positioning could result in geographic misses. We have recently reported on an improved method of customized face mask production using laser surface scanning. In this report, we sought to identify and develop a method to routinely make customized neck supports for patients prescribed radiotherapy to the brain or head and neck regions. We identified a potentially suitable product--sealed packs containing two liquids that produce expanding polyurethane foam when mixed--and developed a method for their use. The neck supports are inexpensive and simple to produce (taking less than 5 min of radiation therapist labour). We assessed the customized neck supports in several ways. The effect on setup accuracy was assessed by comparing two consecutive cohorts of patients. Statistically significant differences favouring the customized neck supports included a reduced total displacement error (mean 3.4 vs. 2.1 mm) and a reduced left-right setup error (mean 1.8 vs. 1.1 mm). This is consistent with the greater support provided by the customized neck supports. This method could easily be undertaken by other departments.


Asunto(s)
Tirantes/economía , Diseño de Equipo/economía , Diseño de Equipo/métodos , Inmovilización/instrumentación , Cuello , Radioterapia Conformacional/economía , Radioterapia Conformacional/instrumentación , Australia , Análisis de Falla de Equipo , Humanos , Postura
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