Intensity-modulated radiotherapy (IMRT) has become established in many clinics round the world and is, arguably, technically feasible in any facility. Serial tomotherapy contributed an extensive role in its introduction into the mainstream in the second half of the 1990s. In tomotherapy, literally "slice therapy", highly conformal treatments are possible because of the advantages available within the treatment planning of the IMRT process. Currently the majority of clinics implementing IMRT are doing so using conventional clinical linear accelerators (Linacs) fitted with an integrated multileaf collimator (MLC). At this point in time we may wonder if there is any scope for further dramatic changes in this new technology. As we venture from IMRT initial implementation into image guided therapy it is clear that major changes in approach are still valid and needed. If, at each treatment fraction, we can ensure that treatments are delivered accurately by integration of volumetric imaging into on-line validation, then we can attempt higher levels of conformality. A new treatment machine, the helical tomotherapy system, is available that combines the benefits of tomotherapy with on-line volumetric imaging. In this article we will review this approach and explore its features.

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The main objective of the ESTRO core curricula is to update and harmonise training of the radiation oncologists, medical physicists and RTTs in Europe. It is recommended that the authorities in charge of the respective training programmes throughout Europe harmonise their own curricula according to the common framework.

These findings suggest that the 26S proteasome may provide a general predictive biomarker for radiotherapy outcome.

MRI of the brain can provide images of very high quality revealing detailed information especially concerning the extent of abnormalities. As such MRI has great potential in the radiotherapy (RT) planning of brain tumours. However MRI has rarely been used alone as the basis for treatment planning primarily due to concern over potential geometric distortions. Treatment planning using MRI has therefore usually been carried out in conjunction with CT images. This work demonstrates that geometric distortions can be minimized by using a relatively small field-of-view, an increased receiver bandwidth, and a fast spin echo acquisition sequence, and that it is thus possible to perform RT planning using MRI.

Objectives: The purpose of this study was to develop and validate a computer model to produce realistic simulated computed radiography (CR) chest images using CT data sets of real patients. Methods: Anatomical noise, which is the limiting factor in determining pathology in chest radiography, is realistically simulated by the CT data, and frequency-dependent noise has been added post-digitally reconstructed radiograph (DRR) generation to simulate exposure reduction. Realistic scatter and scatter fractions were measured in images of a chest phantom acquired on the CR system simulated by the computer model and added post-DRR calculation. Results: The model has been validated with a phantom and patients and shown to provide predictions of signal-to-noise ratios (SNRs), tissue-to-rib ratios (TRRs: a measure of soft tissue pixel value to that of rib) and pixel value histograms that lie within the range of values measured with patients and the phantom. The maximum difference in measured SNR to that calculated was 10%. TRR values differed by a maximum of 1.3%. Conclusion: Experienced image evaluators have responded positively to the DRR images, are satisfied they contain adequate anatomical features and have deemed them clinically acceptable. Therefore, the computer model can be used by image evaluators to grade chest images presented at different tube potentials and doses in order to optimise image quality and patient dose for clinical CR chest radiographs without the need for repeat patient exposures.

Objective: A combination of CT and MRI is recommended for radiotherapy planning of head and neck cancers, and optimal spatial co-registration is achieved by imaging in the treatment position using the necessary immobilisation devices on both occasions, something which requires wide-bore scanners. Quality assurance experiments were carried out to commission a newly installed 1.5-T widebore MRI scanner and a dedicated, flexible six-channel phased array head and neck coil. Methods: Signal-to-noise ratio (SNR) and spatial signal uniformity were quantified using a homogeneous aqueous phantom, and geometric distortion was quantified using a phantom with water-filled fiducials in a grid pattern. Volunteer scans were also used to determine the in vivo image quality. Clinically relevant T 1 weighted and T 2 weighted fat-suppressed sequences were assessed in multiple scan planes (both sequences fast spin echo based). The performance of two online signal uniformity correction schemes, one utilising low-resolution reference scans and the other not utilising low-resolution reference scans, was compared. Results: Geometric distortions, for a 635-kHz bandwidth, were ,1 mm for locations within 10 cm of the isocentre rising to 1.8 mm at 18 cm away. SNR was above 50, and uniformity in the axial plane was 71% and 95% before and after uniformity correction, respectively. Conclusion: The combined performance of the wide-bore scanner and the dedicated coil was adjudged adequate, although superior-inferior spatial coverage was slightly limited in the lower neck. Advances in knowledge: These results will be of interest to the increasing number of oncology centres that are seeking to incorporate MRI into planning practice using dedicated equipment.

Radiotherapy is the standard treatment for head and neck squamous cell carcinoma (HNSCC), however, radioresistance remains a major clinical problem despite significant improvements in treatment protocols. Therapeutic outcome could potentially be improved if a patient's tumour response to irradiation could be predicted ex vivo before clinical application. The present study employed a bespoke microfluidic device to maintain HNSCC tissue whilst subjecting it to external beam irradiation and measured the responses using a panel of cell death and proliferation markers. HNSCC biopsies from five newly-presenting patients [2 lymph node (LN); 3 primary tumour (PT)] were divided into parallel microfluidic devices and replicates of each tumour were subjected to single-dose irradiation (0, 5, 10, 15 and 20 Gy). Lactate dehydrogenase (LDH) release was measured and tissue sections were stained for cytokeratin (CK), cleaved-CK18 (cCK18), phosphorylated-H2AX (γH2AX) and Ki‑67 by immunohistochemistry. In addition, fragmented DNA was detected using terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL). Compared with non‑irradiated controls, higher irradiation doses resulted in elevated CK18-labelling index in two lymph nodes [15 Gy; 34.8% on LN1 and 31.7% on LN2 (p=0.006)] and a single laryngeal primary tumour (20 Gy; 31.5%; p=0.014). Significantly higher levels of DNA fragmentation were also detected in both lymph node samples and one primary tumour but at varying doses of irradiation, i.e., LN1 (20 Gy; 27.6%; p=0.047), LN2 (15 Gy; 15.3%; p=0.038) and PT3 (10 Gy; 35.2%; p=0.01). The γH2AX expression was raised but not significantly in the majority of samples. The percentage of Ki‑67 positive nuclei reduced dose-dependently following irradiation. In contrast no significant difference in LDH release was observed between irradiated groups and controls. There is clear inter- and intra-patient variability in response to irradiation when measuring a variety of parameters, which offers the potential for the approach to provide clinically valuable information.