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Background To optimize palliation in incurable locally advanced non-small cell lung cancer (NSCLC), the International Atomic Energy Agency conducted a prospective randomized study (NCT00864331) comparing protracted palliative radiotherapy (RT) course with chemotherapy (CHT) followed by short-course palliative RT. Methods and materials Treatment-naive patients with histologically confirmed NSCLC, stage IIIA/IIIB, received either 39 Gy in 13 fractions as RT alone (arm A, n = 31) or 2–3 platinum-based CHT cycles followed by 10 Gy in a single fraction or 16 Gy in 2 fractions separated by one week (arm B, n = 34). Primary outcome was overall survival. Results Treatment groups were balanced with respect to various variables. Median survival for all 65 patients was 8 months, while median survival was 7.1 and 8.1 months for the two arms, respectively (log-rank p = 0.4 by study arm, and p = 0.6 by Cox regression and stratified by country and sub-stage). One and three year survival rates for the two arms were 29%, and 9% and 41%, and 6%, respectively. There were no differences in any of the following endpoints: any failure, local failure, regional failure, contralateral thoracic failure, and distant failure between the two arms. High-grade (⩾3) toxicity was similar between the two arms. Symptoms, adverse events of any kind, KPS and body-mass index, were not different during treatment and during follow-up. There was no grade 5 toxicity. Conclusions This incomplete and underpowered trial only hinted similar outcome between the treatment arms. Therefore, combined CHT-RT can perhaps be considered, in limited resource setting, where access to RT remains inadequate. [ABSTRACT FROM AUTHOR]

Background To determine the optimal single-dose radiotherapy schedule for pain from bone metastases in a multi-centre, international, randomised trial. Patients and methods 651 patients were randomised to either 8 Gy ( n = 325) or 4 Gy ( n = 326) radiotherapy. Pain at 4, 8, 12, 24 and 52 weeks was assessed using a Categorical Scale (CS) and a Visual Analogue Scale (VAS). The primary endpoint was response at 4 weeks. Results There was no significant difference in patient demographics and other co-variates. The complete response (CR) rate and ORR (complete or partial response) for all follow-up times were higher after 8 Gy ( p = 0.02). The Kaplan–Meier actuarial rate (categorical scale) at 4 weeks for ORR was 80% after 8 Gy compared to 68% after 4 Gy ( p = 0.0015). 117 re-treatments were given of which 72 were in the 4 Gy group and 45 in 8 Gy arm ( p = 0.01). Conclusions There was a marked consistent difference in pain relief at all time points in favour of 8 Gy. These data reinforce the case for single dose 8 Gy radiotherapy to be recommended for metastatic bone pain in all healthcare settings. [ABSTRACT FROM AUTHOR]

To evaluate the current status of stereotactic body radiotherapy (SBRT) and identify both advantages and disadvantages of its use in developing countries, a meeting composed of consultants of the International Atomic Energy Agency was held in Vienna in November 2006. Owing to continuous developments in the field, the meeting was extended by subsequent discussions and correspondence (2007–2010), which led to the summary presented here. The advantages and disadvantages of SBRT expected to be encountered in developing countries were identified. The definitions, typical treatment courses, and clinical results were presented. Thereafter, minimal methodology/technology requirements for SBRT were evaluated. Finally, characteristics of SBRT for developing countries were recommended. Patients for SBRT should be carefully selected, because single high-dose radiotherapy may cause serious complications in some serial organs at risk. Clinical experiences have been reported in some populations of lung cancer, lung oligometastases, liver cancer, pancreas cancer, and kidney cancer. Despite the disadvantages expected to be experienced in developing countries, SBRT using fewer fractions may be useful in selected patients with various extracranial cancers with favorable outcome and low toxicity. [ABSTRACT FROM AUTHOR]

Abstract: Background and purpose: Help identify and define potential normal tissue dose constraints to minimize the mortality and morbidity of hypofractionated lung radiotherapy. Materials and methods: A method to generate isodose-based constraints and visually evaluate treatment plans, based on the published peer reviewed literature and the linear quadratic model, is presented. The radiobiological analysis assumes that the linear quadratic model isvalid up to 28Gy per fraction, the α/β ratio is 2 for the spinal cord and brachial plexus, 4 for pneumonitis, 4 or 10 for acute skin reactions depending on treatment length, and 3 for late complications in other normal tissues. A review of the literature was necessary to identify possible endpoints and normal tissue constraints for thoracic hypofractionated lung radiotherapy. Results: Preliminary normal tissue constraints to reduce mortality and morbidity were defined for organs at risk based upon hypofractionated lung radiotherapy publications. A modified dose nomenclature was introduced to facilitate the comparison of hypofractionated doses. Potential side effects from hypofractionated lung radiotherapy such as aortic dissection, neuropathy, and fatal organ perforation rarely seen in conventional treatments were identified. The isodose-based method for treatment plan analysis and normal tissue dose constraint simplification was illustrated. Conclusions: The radiobiological analysis based on the LQ method, biologically equivalent dose nomenclature, and isodose-based method proposed in this study simplifies normal tissue dose constraints and treatment plan evaluation. This may also be applied to extrathoracic hypofractionated radiotherapy. Prospective validation of these preliminary thoracic normal tissue dose constraints for hypofractionated lung radiotherapy is necessary. [Copyright &y& Elsevier]

Abstract: Positron Emission Tomography (PET) is a significant advance in cancer imaging with great potential for optimizing radiation therapy (RT) treatment planning and thereby improving outcomes for patients. The use of PET and PET/CT in RT planning was reviewed by an international panel. The International Atomic Energy Agency (IAEA) organized two synchronized and overlapping consultants’ meetings with experts from different regions of the world in Vienna in July 2006. Nine experts and three IAEA staff evaluated the available data on the use of PET in RT planning, and considered practical methods for integrating it into routine practice. For RT planning, 18F fluorodeoxyglucose (FDG) was the most valuable pharmaceutical. Numerous studies supported the routine use of FDG-PET for RT target volume determination in non-small cell lung cancer (NSCLC). There was also evidence for utility of PET in head and neck cancers, lymphoma and in esophageal cancers, with promising preliminary data in many other cancers. The best available approach employs integrated PET/CT images, acquired on a dual scanner in the radiotherapy treatment position after administration of tracer according to a standardized protocol, with careful optimization of images within the RT planning system and carefully considered rules for contouring tumor volumes. PET scans that are not recent or were acquired without proper patient positioning should be repeated for RT planning. PET will play an increasing valuable role in RT planning for a wide range of cancers. When requesting PET scans, physicians should be aware of their potential role in RT planning. [Copyright &y& Elsevier]