Categorisation of patientswith CHD with the IPAQ quickly provides clinical information as HEPA patients have a less probability for impaired HrQoL and diminished exercise capacity. Nevertheless, the IPAQ cannot substitute an accelerometer-based assessment for PA, nor a CPET for exercise capacity.
With increasing cure rates of breast cancer, radiotherapy-induced cancers have become an important issue. This study aims at estimating secondary cancer risks for different treatment techniques, taking into account organs throughout the body.Material and Methods: Organ doses were evaluated for a tangential threedimensional conformal (3D-CRT) and a multi-field intensity-modulated radiotherapy (IMRT) plan using a validated, Monte Carlo based, treatment planning system. Effects of wedges and of forward versus inverse planning were systematically investigated on the basis of phantom measurements. Organspecific cancer risks were estimated using risk coefficients derived from radiotherapy patients or from the atomic bomb survivors.Results: In the 3D-CRT plan mean organ doses could be kept below 1 Gy for more remote organs than lung, heart, and contralateral breast, and declined to a few cGy for organs in the lower torso. Multi-field IMRT led to considerably higher mean doses in organs at risk, the difference being higher than 50% for many organs. Likewise, peripheral radiation burden was increased by external wedges. No difference was observed for forward versus inverse planning.Despite the lower doses, the total estimated secondary cancer risk in more remote organs was comparable to that in the lung or the contralateral breast.For multi-field IMRT it was 75% higher than for 3D-CRT without external wedges. Conclusion:Remote organs are important for assessment of radiation-induced cancer risk. Remote doses can be reduced effectively by application of a tangential field configuration and a linear accelerator set-up with low head scatter radiation.
Purpose Several studies have demonstrated the negative impact of radiotherapy protocol deviations on tumor control in medulloblastoma. In the SIOP PNET5 MB trial, a pretreatment radiotherapy quality control (RT-QC) program was introduced. A first analysis for patients enrolled in Germany, Switzerland and Austria with focus on types of deviations in the initial plan proposals and review criteria for modern radiation technologies was performed. Methods and patients Sixty-nine craniospinal irradiation (CSI) plans were available for detailed analyses. RT-QC was performed according to protocol definitions on dose uniformity. Because of the lack of definitions for high-precision 3D conformal radiotherapy within the protocol, additional criteria for RT-QC on delineation and coverage of clinical target volume (CTV) and planning target volume (PTV) were defined and evaluated. Results Target volume (CTV/PTV) deviations occurred in 49.3% of initial CSI plan proposals (33.3% minor, 15.9% major). Dose uniformity deviations were less frequent (43.5%). Modification of the RT plan was recommended in 43.5% of CSI plans. Unacceptable RT plans were predominantly related to incorrect target delineation rather than dose uniformity. Unacceptable plans were negatively correlated to the number of enrolled patients per institution with a cutoff of 5 patients (p = 0.001). Conclusion This prospective pretreatment individual case review study revealed a high rate of deviations and emphasizes the strong need of pretreatment RT-QC in clinical trials for medulloblastoma. Furthermore, the experiences point out the necessity of new RT-QC criteria for high-precision CSI techniques.
Breast cancer radiotherapy may in the long term lead to radiation-induced secondary cancer or heart disease. These health risks hugely vary among patients, partially due to anatomy-driven differences in doses deposited to the heart, ipsilateral lung and contralateral breast. We identify four anatomic features that largely cover these dosimetric variations to enable personalized risk estimates. For three exemplary, very different risk scenarios, the given parameter set reproduces 63–74% of the individual risk variability for left-sided breast cancer patients. These anatomic features will be used in the PASSOS software to support decision processes in breast-cancer therapy.
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