Carbon fibre couch inserts are widely used in external beam radiotherapy to provide rigid and lightweight patient support. Carbon fibre is often perceived to be essentially radiotranslucent implying that it does not interfere with the radiation beam. However, there is evidence in the literature which suggests that this perception may not be appropriate, particularly at oblique angles of incidence. Furthermore, there is evidence indicating that the use of carbon fibre significantly reduces the skin sparing effect. In this study, the radiation attenuation and surface dose enhancement characteristics of the carbon fibre insert for the Varian ExactTM couch have been investigated. It was found that attenuation increased significantly with increasing angle of incidence, resulting in in-phantom dose reductions of up to 6% at 6 MV and 4% at 15 MV. It has been shown that it is possible to model couch attenuation on a commercial treatment planning system (Elekta CMS XiO) by including the carbon fibre insert in the planning computed tomography (CT) dataset. Finally, the carbon fibre insert was found to significantly increase skin dose to the patient. The skin dose was approximately three times as large when the couch insert was added to 6 and 15 MV photon beams. However, even with this substantial increase it is highly unlikely that the skin tolerance dose will be exceeded.

Objective: To examine the outcomes of patients with adenoid cystic carcinoma (ACC) treated with post-operative accelerated hypofractionated radiotherapy (AHRT).

Methods: Patients treated with AHRT (50–55 Gy in 20 fractions over 25 days) between 1997 and 2008 were identified and retrospectively analysed. Data collection included site of primary and surgical excision margin. Primary outcomes were overall survival (OS) and local control (LC) calculated using the Kaplan–Meier method.

Results: A total of 37 patients meeting the above criteria were identified with a median age of 55 years (range 31–79). Distribution by anatomical site was as follows: parotid 9 patients; submandibular gland 8 patients; other salivary gland tissue 20 patients. Surgical excision margins were as follows: non-involved 25 patients; microscopic involvement 7 patients; macroscopic involvement 4 patients; unknown 1 patient. Median follow-up was 59 (range 14–126) months. Five patients had local recurrence, 4 distant recurrences, and 1 both local and distant recurrence. The 5-year LC and OS rates were 81.8% (95% confidence intervals (CIs) 60.9–92.2) and 78.5% (95% CI 58.0–89.8%), respectively.

Conclusion: Outcomes with post-operative AHRT appear comparable to those in the literature. However, until more is known about the radiobiology of this rare disease, a biological equivalent of 60 Gy in 2 gray fractions without correction for accelerated repopulation should be used.

Purpose: To evaluate composite coplanar and non-coplanar three-dimensional conformal techniques (3D-CRT) for external-beam prostate radiotherapy using a low-energy (6 MV) photon beam.

Methods and Materials: For treatment-planning purposes, three different planning target volumes (PTV) were defined for ten patients with prostate cancer and as follows: PTV1 (pelvis), PTV2 (prostate + seminal vesicles + 1 cm margin) and PTV3 (prostate + 1 cm margin). Conformal techniques of 2, 3, 4, 5 (coplanar) and 6 (non-coplanar) field techniques have been considered and combined to produce five different plan combinations (i.e. techniques A, B, C, D and E). Treatment plans were generated with a prescription dose of 75 Gy to PTV3, 65 Gy to PTV2 and 45 Gy to PTV1 and were assessed on the basis of 3D dose distributions and dose-volume histograms (DVHs). Normal tissue-dose constraints for the relevant organs at risk (OARs), that is, rectum, bladder and femoral heads, were also considered.

Results: Findings show that all five treatment-plan combinations result in adequate PTV coverage and acceptable OAR irradiated volumes. The greatest rectal spacing in the high-dose region is achieved by technique C; all techniques achieve this, except for technique A, and give approximately the same fraction of volume (of rectum) that receives a dose of 50 Gy (V50) and 60 Gy (V60). When considering the bladder, techniques B, D and E give the best bladder sparing with small absolute differences, whereas technique A results in the lowest dose for femoral heads. Technique E appears to give the best compromise for all three considered OARs, provided the PTV is adequately covered.

Conclusions: Even though the optimum photon-beam energy for conformal prostate radiotherapy is greater than 10 MV, our study shows that a good sparing of OAR can be achieved even with a lower-energy beam (6 MV) and the appropriate plan combination and that the dose to prostate can be as high as 75 Gy.

Purpose: This study aimed to explore the patient’s experience of the radiotherapy pathway with a view to improving patient-centred services.

Methods: Women’s views about the radiotherapy pathway were gathered through a focus group. Focus groups have been used extensively in qualitative research to gather rich meaningful data. A thematic analysis of the transcript identified areas of importance for the women, which could be used to direct service improvement.

Results: Five main themes emerged: information, communication and support, dignity and individualised care, service accessibility and staff relationships. Generally, staff were viewed as professionals and the radiotherapy service well run although women did identify several unmet needs during radiotherapy. Lack of information and perceived time constraints of busy staff was revealed. However women did feel treated with dignity, respect and as individuals. ‘End-of-treatment’ was a particular focus; women felt dedicated time with staff would enable discussion, information giving and support around this vulnerable time. In addition, women felt that communication barriers and time constraints influenced the information and support they experienced during radiotherapy.

Conclusion: The use of a focus group enabled service users to identify clear areas for improvement at a local level. Priorities include information, communication and support and the ‘end-of-treatment’.

The assessment of mean lethal radiation dose (D0) in human organs, using multi-target and linear quadratic models, with water proton nuclear magnetic resonance spin lattice relaxation time yields a correlation coefficient of 0.90 and 0.82, respectively. Results of this study reveal that as the spin lattice relaxation time increases, the D0 decreases.

The sharp dose gradients in intensity-modulated radiation therapy increase the treatment sensitivity to various inter- and intra-fractional uncertainties, in which a slight anatomical change may greatly alter the actual dose delivered. Image-guided radiotherapy refers to the use of advanced imaging techniques to precisely track and correct these patient-specific variations in routine treatment. It can also monitor organ changes during a radiotherapy course. Currently, image-guided radiotherapy using computed tomography has gained much popularity in radiotherapy verification as it provides volumetric images with soft-tissue contrast for on-line tracking of tumour. This article reviews four types of computed tomography-based image guidance systems and their working principles. The system characteristics and clinical applications of the helical, megavoltage, computed tomography, and kilovoltage, cone-beam, computed tomography systems are discussed, given that they are currently the most commonly used systems for radiotherapy verification. This article also focuses on the recent techniques of soft-tissue contrast enhancement, digital tomosynthesis, four-dimensional fluoroscopic image guidance, and kilovoltage/megavoltage, in-line cone-beam imaging. These evolving systems are expected to take over the conventional two-dimensional verification system in the near future and provide the basis for implementing adaptive radiotherapy.

This patient case study represents the introduction of adaptive radiotherapy (ART) at the Andrew Love Cancer Centre (ALCC) with non-uniform margins for invasive bladder cancer treatment. Invasive bladder cancer has historically had poor local control with radiotherapy treatment; however, with the introduction of cone-beam computer tomography (CBCT) and adaptive treatment, there is potential for improvements in disease control and reduced toxicities.