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Background. Well-specified and unambiguous treatment protocols are essential both for current practice and for the future development of radiation therapy. In order to provide assistance for writing good protocols, irrespective of treatment intention and complexity, up-to-date guidelines are highly desirable. Methods. We have analysed the radiotherapy work-flow, including clinical and physical aspects, such as preparatory imaging, treatment planning, delivery and evaluation, with the aim to outline a consistent framework covering the entire radiotherapy process. Results. Based on the analysis, a recipe-style template for specifying the description of the radiotherapy process has been designed. The template is written in a general format, which allows for modified phrasing, and should be customised for the specific clinical situation and diagnosis, as well as facility resources. Conclusions. The template can be used as a tool to ensure a consistent and comprehensive description of the radiotherapy section of clinical guidelines, care programmes and clinical trial protocols.

Background. In SBRT of lung tumours no established relationship between dose-volume parameters and the incidence of lung toxicity is found. The aim of this study is to compare the LQ model and the universal survival curve (USC) to calculate biologically equivalent doses in SBRT to see if this will improve knowledge on this relationship. Material and methods. Toxicity data on radiation pneumonitis grade 2 or more (RP2+) from 57 patients were used, 10.5% were diagnosed with RP2+. The lung DVHs were corrected for fractionation (LQ and USC) and analysed with the Lyman-Kutcher-Burman (LKB) model. In the LQ-correction alpha/beta = 3 Gy was used and the USC parameters used were: alpha/beta = 3 Gy, D-0 = 1.0 Gy, (n) over bar = 10, alpha = 0.206 Gy(-1) and d(T) = 5.8 Gy. In order to understand the relative contribution of different dose levels to the calculated NTCP the concept of fractional NTCP was used. This might give an insight to the questions of whether "high doses to small volumes" or "low doses to large volumes" are most important for lung toxicity. Results and Discussion. NTCP analysis with the LKB-model using parameters m = 0.4, D-50 = 30 Gy resulted for the volume dependence parameter (n) with LQ correction n = 0.87 and with USC correction n = 0.71. Using parameters m = 0.3, D-50 = 20 Gy n = 0.93 with LQ correction and n = 0.83 with USC correction. In SBRT of lung tumours, NTCP modelling of lung toxicity comparing models (LQ, USC) for fractionation correction, shows that low dose contribute less and high dose more to the NTCP when using the USC-model. Comparing NTCP modelling of SBRT data and data from breast cancer, lung cancer and whole lung irradiation implies that the response of the lung is treatment specific. More data are however needed in order to have a more reliable modelling.

Background. In SBRT of lung tumours no established relationship between dose-volume parameters and the incidence of lung toxicity is found. The aim of this study is to compare the LQ model and the universal survival curve (USC) to calculate biologically equivalent doses in SBRT to see if this will improve knowledge on this relationship. Material and methods. Toxicity data on radiation pneumonitis grade 2 or more (RP2+) from 57 patients were used, 10.5% were diagnosed with RP2+. The lung DVHs were corrected for fractionation (LQ and USC) and analysed with the Lyman-Kutcher-Burman (LKB) model. In the LQ-correction alpha/beta = 3 Gy was used and the USC parameters used were: alpha/beta = 3 Gy, D-0 = 1.0 Gy, (n) over bar = 10, alpha = 0.206 Gy(-1) and d(T) = 5.8 Gy. In order to understand the relative contribution of different dose levels to the calculated NTCP the concept of fractional NTCP was used. This might give an insight to the questions of whether "high doses to small volumes" or "low doses to large volumes" are most important for lung toxicity. Results and Discussion. NTCP analysis with the LKB-model using parameters m = 0.4, D-50 = 30 Gy resulted for the volume dependence parameter (n) with LQ correction n = 0.87 and with USC correction n = 0.71. Using parameters m = 0.3, D-50 = 20 Gy n = 0.93 with LQ correction and n = 0.83 with USC correction. In SBRT of lung tumours, NTCP modelling of lung toxicity comparing models (LQ, USC) for fractionation correction, shows that low dose contribute less and high dose more to the NTCP when using the USC-model. Comparing NTCP modelling of SBRT data and data from breast cancer, lung cancer and whole lung irradiation implies that the response of the lung is treatment specific. More data are however needed in order to have a more reliable modelling.

PURPOSE: The impact of stereotactic body radiotherapy (SBRT) on 3-year progression-free survival of medically inoperable patients with stage I non-small-cell lung cancer (NSCLC) was analyzed in a prospective phase II study. PATIENTS AND METHODS: Fifty-seven patients with T1NOMO (70%) and T2N0M0 (30%) were included between August 2003 and September 2005 at seven different centers in Sweden, Norway, and Denmark and observed up to 36 months. SBRT was delivered with 15 Gy times three at the 67% isodose of the planning target volume. RESULTS: Progression-free survival at 3 years was 52%. Overall- and cancer-specific survival at 1, 2, and 3 years was 86%, 65%, 60%, and 93%, 88%, 88%, respectively. There was no statistically significant difference in survival between patients with T1 or T2 tumors. At a median follow-up of 35 months (range, 4 to 47 months), 27 patients (47%) were deceased, seven as a result of lung cancer and 20 as a result of concurrent disease. Kaplan-Meier estimated local control at 3 years was 92%. Local relapse was observed in four patients (7%). Regional relapse was observed in three patients (5%). Nine patients (16%) developed distant metastases. The estimated risk of all failure (local, regional, or distant metastases) was increased in patients with T2 (41%) compared with those with T1 (18%) tumors (P = .027). CONCLUSION: With a 3-year local tumor control rate higher than 90% with limited toxicity, SBRT emerges as state-of-the-art treatment for medically inoperable stage I NSCLC and may even challenge surgery in operable instances.