To investigate the necessity of rotational shifts by considering dosimetric impact of rotational errors on stereotactic body radiation therapy (SBRT).

20 lung patients with the lesion size <5 cm treated with SBRT have been selected for dosimetric analysis. Three-dimensional dose has been rotationally shifted (±1°, ±3°, ±5° for pitch, roll and yaw) and overlaid to the original computed tomography images. The dose–volume histograms of 18-rotational plans of each patient were compared to those of the original plan.

No significant dosimetric differences were observed in target coverage. For all of the cases up to 5° in any couch angle dose differences of D99 and D95 were <3%. Variations of conformity index were observed to be less than 0·05. None of the organ at risk doses exceeded the dose limit. The V20 differences of the ipsilateral and the total lungs were less than 0·4%.

It has been found to be unnecessary to perform rotational shifts up to 5° for lung SBRT treatments; the translational shift is sufficient for the cases used in this study. This method may be applied and tested after planning and before treatment initiation to rule out exceptionally extreme cases.

This study aimed to compare intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) regarding plan quality and healthy lung sparing, in stage III non-small cell lung cancer (NSCLC) patients.

The plans of 60 patients were allocated either to the IMRT (n=30) or the VMAT (n=30) group. The dose prescribed to the planning target volume (PTV) was evaluated at the 95% level and the mean lung dose (MLD) and the healthy lung receiving 5, 10 and 20 Gy (V5, V10 and V20, respectively) were analysed. The normal tissue complication probability (NTCP) for radiation pneumonitis was calculated with the Lyman–Kutcher–Burman model.

Both techniques achieved comparable results for target coverage (V95%=97·87 versus 97·18%, p>0·05) and homogeneity. The MLD (15·57 versus 16·98 Gy, p>0·05), V5 (60·35 versus 67·25%, p>0·05) and V10 (45·22 versus 53·14%, p=0·011) were lower for IMRT, whereas VMAT reduced V20 (26·44 versus 25·90%, p>0·05). The NTCP for radiation pneumonitis was higher for VMAT, but no statistical significance was observed (11·07 versus 12·75, p>0·05).

Both techniques seemed suitable for NSCLC treatment, but IMRT presented better results regarding lung sparing thus being beneficial in reducing the risk of radiation-induced pneumonitis.

To characterise small photon beams using the Monte Carlo dose calculation algorithm for small field ranges in a heterogeneous medium.

An in-house phantom constructed with three different mediums, foam, polymethyl methacrylate and delrin resembling the densities of lung, soft tissue and bone respectively, was used in this study. Photon beam energies of 6 and 15 MV and field sizes of 8×8, 16×16, 24×24, 32×32 and 40×40 mm using X-ray voxel Monte Carlo (XVMC) algorithm using different detectors were validated. The relative output factor was measured in three different mediums having six different tissue interfaces; at the depth of 0, 1, 2 and 3 cm. The planar dose verification was undertaken using gafchromic films and considered dose at the lung and bone medium interfaces. For all the measurements, 104×104 mm was taken as the reference field size. The relative output factor for all other field sizes was taken and compared with planning system calculated values.

From field size 16×16 mm and above, the relative output factors were analysed in bone and soft tissue medium having lung as first medium. The maximum deviations were observed as 1·8 and 1·3% for 6 MV and 2·5 and 1·1% for 15 MV photon beams for bone and soft tissue, respectively. For lung as measurement medium, the maximum deviation of 14·8 and 19·2% were observed and having bone as first medium with 8×8 mm for 6 and 15 MV photon beams, respectively. The fluence verification of dose spectrum for the lung–bone interface scenarios with smaller field sizes were found within 2% of deviation with treatment planning system (TPS).

The accuracy of dose calculations for small field sizes in XVMC-based treatment planning algorithm was studied in different inhomogeneous mediums. It was found that the results correlated with measurement data for field size 16×16 mm and above. Noticeable deviation was observed for the smallest field size of 8×8 mm with interfaces of significant change in density. The observed results demands further analysis of work with smaller field sizes.

The novel three-dimensional (3D) radiotherapy interactive outlining tool allows volumes to be created from a handful of points within axial, sagittal and coronal planes. 3D volumetric visualisation allows users to directly manipulate the resulting volume using innovative-sculpting tools. This paper discusses the development and initial evaluation of the software ahead of formal clinical testing.

User feedback was collated as part of the software development phase to ensure clinical suitability, define user training strategies and identify best practice. A loosely structured format was adopted with leading descriptive questions aiming to generate suggestions for improvements and initiate further discussion.

The four participants reported great satisfaction and value in being able to use all three planes for outlining, although orientation in 3D was evidently a problem. All participants felt that the software was capable of producing acceptable outlines rapidly and that the multi-planar capability allowed for improved outlining of the prostate apex.

Mesh generation from a small number of points placed on a range of planes is a rapid and effective means of target delineation. Multi-slice volume sculpting and 3D orientation is challenging and may indicate a need for a paradigm shift in anatomy and computed tomography training.

To evaluate the quality of rectal hydrogel spacer (HS) insertions from literature in patients undergoing radical radiotherapy for prostate cancer. The secondary aim is to assess the benefit of HSs in patients with risk factors more likely to have rectal complications, such as non-conventional radiotherapy dose fractionations and high-risk disease.

A literature search of peer-reviewed electronic articles was carried out using Boolean connectors and Medical Subject Headings in the databases. Databases searched included ScienceDirect, Medline and Cinahl. The articles were assessed using relevant critical appraisal skills programme tools.

From the 26 studies used, HS showed a clinically significant relative reduction in rectal planning dose volumes for both high- and low-risk prostate cancer patients in a range of radiotherapy treatment modalities including volumetric modulated arc therapy, intensity-modulated radiotherapy, intensity-modulated proton therapy, stereotactic ablative body radiotherapy and brachytherapy. Spacer placements were successfully inserted in 99% of patients. However, rectal wall infiltration occurrence was 6% and ≥2 cm unsymmetrical placements in 2%.

A spacer scoring system based on the HS symmetry has provided evidence of the quality of the position inserted, which was visually aided by T2-wieghted MRIs. Despite optimal HS placements ranging from 62 to 72%, HS had a clinically significant reduction of ≥25% in planned rectal V70 dose in 97% of patients.

Accurate delineation of the target volume and organs at risk (OARs) are vital to ensure systematic errors are small. The use of contrast agents (CAs) in the bladder and rectum may aid contouring and reduce inter and intra-observer variability. The aim of this study was to evaluate the dosimetric effect of the presence of such contrast on the monitor units (MUs), planning target volume (PTV), rectum and bladder.

The prostate, seminal vesicles, rectum and bladder were contoured by a single observer on ten patients with bladder and rectal contrast. To evaluate the dosimetric effect of the presence of contrast, the density of the ten patients with contrast in the bladder and rectum was virtually changed to 1 g/cm3. A four-field 15 MV conformal radiation therapy technique was applied in which dose volume histograms and MUs were compared using computed tomographic (CT) density and the 1 g/cm3 density.

The presence of contrast resulted in a 0·09% (<1 MU) increase in anterior MUs and decrease of 1% (<1 MU) in the posterior beam MUs. Lateral beams were not affected. The PTV and bladder dose increased slightly without contrast. The rectum showed a maximum change of 0·62% dose among the measured dose values. A maximum dose of 0·3 Gy at the 30% volume was also seen.

The dosimetric effect of bladder and rectal CAs on MUs, dose to the PTV and OARs in using this technique was very small. This would not be clinically significant, but only if the extreme limits of dose volume constraints were being reached.

This study aimed to systematically review the literature to synthesise and summarise whether using knowledge-based planning (KBP) can improve the planning of stereotactic radiotherapy treatments.

A systematic literature search was carried out using Medline, Scopus and Cochrane databases to evaluate the use of KBP planning in stereotactic radiotherapy. Three hundred twenty-five potential studies were identified and screened to find 25 relevant studies.

Twenty-five studies met the inclusion criteria. Where a commercial KBP was used, 72.7% of studies reported a quality improvement, and 45.5% reported a reduction in planning time. There is evidence that when used as a quality control tool, KBP can highlight stereotactic plans that need revision. In studies that use KBP as the starting point for radiotherapy planning optimisation, the radiotherapy plans generated are typically equal to or superior to those planned manually.

There is evidence that KBP has the potential to improve the quality and speed of stereotactic radiotherapy planning. Further research is required to accurately quantify such systems’ quality improvements and time savings. Notably, there has been little research into their use for prostate, spinal or liver stereotactic radiotherapy, and research in these areas would be desirable. It is recommended that future studies use the ICRU 91 level 2 reporting format and that blinded physician review could add a qualitative assessment of KBP system performance.

An emerging developmental tool to help radiation therapists achieve better outcomes is ‘peer review’. This review of the current literature summarises the challenges and benefits of peer review in both individual and departmental practice.

There is compelling evidence supporting peer review implementation at both individual and department level in many professions. Implementing peer review requires that radiation therapists and other radiation oncology professionals embrace a culture that supports safety. Peer review can identify trends and barriers associated with quality radiotherapy and share best practice or recommend changes accordingly. Support for peer review must come from pre-registration educational systems as well as clinical managers. Continuing professional development in the workplace is nurtured by peer review of radiotherapy practice and an aptitude for this should be viewed as important to the profession as technical and clinical skills.

It is clear that peer review has the potential to facilitate reflective practice, improve staff motivation and help foster a culture of quality and safety in radiation oncology. To drive the issues of quality and safety a step further radiation therapists need to accept the challenge of adopting peer review methods in day-to-day practice.

Pelvic internal organs change in volume and position during radiotherapy. This may compromise the efficacy of treatment or worsen its toxicity. There may be limitations to fully correcting these changes using online image guidance; therefore, effective and consistent patient preparation and positioning remain important. This review aims to provide an overview of the extent of pelvic organ motion and strategies to manage this motion.

Given the breadth of this topic, a systematic review was not undertaken. Instead, existing systematic reviews and individual high-quality studies addressing strategies to manage pelvic organ motion have been discussed. Suggested levels of evidence and grades of recommendation for each strategy have been applied.

Various strategies to manage rectal changes have been investigated including diet and laxatives, enemas and rectal emptying tubes and rectal displacement with endorectal balloons (ERBs) and rectal spacers. Bladder-filling protocols and bladder ultrasound have been used to try to standardise bladder volume. Positioning the patient supine, using a full bladder and positioning prone with or without a belly board, has been examined in an attempt to reduce the volume of irradiated small bowel. Some randomised trials have been performed, with evidence to support the use of ERBs, rectal spacers, bladder-filling protocols and the supine over prone position in prostate radiotherapy. However, there was a lack of consistent high-quality evidence that would be applicable to different disease sites within the pelvis. Many studies included small numbers of patients were non-randomised, used less conformal radiotherapy techniques or did not report clinical outcomes such as toxicity.

There is uncertainty as to the clinical benefit of many of the commonly adopted interventions to minimise pelvic organ motion. Given this and the limitations in online image guidance compensation, further investigation of adaptive radiotherapy strategies is required.

Weekly low-dose cisplatin is routinely used in concurrent chemoradiation (CCRT) in locally advanced head and neck cancer (LAHNC), despite 3-weekly cisplatin being the standard of care. We compared compliance, toxicity and efficacy in weekly versus 3-weekly cisplatin CCRT in LAHNC.

In this retrospective study, weekly cisplatin 50 mg flat dose was compared with 3-weekly cisplatin 100 mg/m2, when given in CCRT in LAHNC with curative intent. The study outcome was compliance, toxicity, loco-regional control (LRC), disease-free survival (DFS) and overall survival (OS).

Eighty-four patients received CCRT from January 2013 to June 2017, 40 in weekly and 44 in 3-weekly arm. There was no difference between the arms not completing scheduled radiation therapy or chemotherapy. Patient receiving 200 mg/m2 cisplatin is higher in 3-weekly arm compared with weekly arm (75 versus 40·9%; p<0·0015). Compared with 3-weekly arm, more patient in weekly arm developed grade ≥3 mucositis (52·5 versus 15·9%, p=0·0004), day care intravenous hydration (82·5 versus 38·6% <0·0001) and in-patient admission (55·0 versus 18·2%; p=0·0004). The 2-year LRC, DFS and OS in weekly versus 3-weekly arm were: 70 versus 61·4% (p=0·406); 67·5 versus 56·8% (p=0·314); 67·5 versus 61·4% (p=0·558), respectively. The median time to LRR, DFs and OS was not reached.

Weekly cisplatin is comparable with 3-weekly cisplatin in terms of compliance, disease control and survival, but with increased grade 3 mucositis and higher admissions for supportive care.

The aim of this study is to develop predictive models to predict organ at risk (OAR) complication level, classification of OAR dose-volume and combination of this function with our in-house developed treatment decision support system.

We analysed the support vector machine and decision tree algorithm for predicting OAR complication level and toxicity in order to integrate this function into our in-house radiation treatment planning decision support system. A total of 12 TomoTherapyTM treatment plans for prostate cancer were established, and a hundred modelled plans were generated to analyse the toxicity prediction for bladder and rectum.

The toxicity prediction algorithm analysis showed 91·0% accuracy in the training process. A scatter plot for bladder and rectum was obtained by 100 modelled plans and classification result derived. OAR complication level was analysed and risk factor for 25% bladder and 50% rectum was detected by decision tree. Therefore, it was shown that complication prediction of patients using big data-based clinical information is possible.

We verified the accuracy of the tested algorithm using prostate cancer cases. Side effects can be minimised by applying this predictive modelling algorithm with the planning decision support system for patient-specific radiotherapy planning.

Nasopharyngeal carcinoma (NPC) patients may have anatomical variations during their radiotherapy treatment course. In this study, we determine the daily accumulated dose by the deformable image registration (DIR) process for comparing with the planned dose and explore the number of fractions which the daily accumulated dose significantly changed from the planned dose.

The validation of the DIR process in MIM software has been tested. One hundred and sixty-five daily megavoltage computed tomography (MVCT) images of NPC patients who were treated by helical tomotherapy were exported to MIM software to determine the daily accumulated dose and then compared with the planned dose.

The MIM software illustrated the acceptable validation for clinical application. The accumulated dose (D50%) of the planning target volume (PTV70) showed a decrease from the planned dose with an average of 0.5 ± 0.27% at the end of the treatment and was significantly different from the planned dose after the second fraction of the treatment (p-value = 0.008). In contrast, the accumulated dose of organ at risk (OAR) tended to increase from the planned dose and was significantly different after the fifth fraction (left parotid), the twelfth fraction (right parotid) and the second fraction (spinal cord).

The inter-fractional anatomic changes cause the actual dose to be different from the planned dose. The dose differences and the number of fractions were varied in each target and OAR. The dose accumulation explored the necessary information for the radiation oncologist to consider adaptive treatment strategies to increase the efficiency of treatment.

Radiotherapy clinical trials are at the forefront of modern-day prostate cancer patient management. Patients are reviewed during treatment by clinical oncologists or competent on-treatment review radiographers to minimise treatment toxicities. Clinical Research Radiographers (CRRs) routinely monitor and gather research data from patients participating in clinical trials.

The aim of this article is to evaluate the effectiveness of the CRR undertaking the on-treatment review of clinical trial patients.

An experienced CRR within the Northern Ireland Cancer Trials Network was supervised by a clinical oncologist to undertake the role of the on-treatment review of patients receiving radiotherapy for prostate cancer. The CRR explored published literature and compiled this written evaluation as part of their advanced practice learning.

The supervising clinical oncologist verified, following the planned period of supervised practice and academic study, that the CRR was competent to fulfil the role. Evidence of the beneficial synergistic impact of co-joining the roles was experienced at first hand during the undertaking of supervised practice.

Co-joining the roles and responsibilities of the CRR and the on-treatment review radiographer enhanced the quality of care offered to the patients participating in clinical trials.

Head and neck cancer patients receiving radiotherapy can experience a number of toxicities, including weight loss and malnutrition, which can impact upon the quality of treatment. The purpose of this retrospective cohort study is to evaluate weight loss and identify predictive factors for this patient group.

A total of 40 patients treated with radiotherapy since 2012 at the study centre were selected for analysis. Data were collected from patient records. The association between potential risk factors and weight loss was investigated.

Mean weight loss was 5 kg (6%). In all, 24 patients lost >5% starting body weight. Age, T-stage, N-stage, chemotherapy and starting body weight were individually associated with significant differences in weight loss. On multiple linear regression analysis age and nodal status were predictive.

Younger patients and those with nodal disease were most at risk of weight loss. Other studies have identified the same risk factors along with several other variables. The relative significance of each along with a number of other potential factors is yet to be fully understood. Further research is required to help identify patients most at risk of weight loss; and assess interventions aimed at preventing weight loss and malnutrition.

Lung cancer has a high mortality rate mainly due to the lack of early detection or outward signs and symptoms, thereby often progressing to advanced stages (e.g., stage IV) before it is diagnosed. However, if lung cancers can be diagnosed at an early stage and also if clinicians can prospectively identify patients likely to respond to specific treatments, then there is a very high potential to increase patients’ survival. In recent years, several investigations have been conducted to identify cancer biomarkers for lung cancer risk assessment, early detection and diagnosis, the likelihood of identifying the group of patients who will benefit from a particular treatment and monitoring patient response to treatment.

This paper reports on the review of 19 current clinical and emerging biomarkers used in risk assessment, screening for early detection and diagnosis and monitoring the response of treatment of non-small-cell lung cancers.

The future holds promise for personalised and targeted medicine from prevention, diagnosis to treatment, which take into account individual patient’s variability, though it depends on the development of effective biomarkers interrogating the key aberrant pathways and potentially targetable with molecular targeted or immunologic therapies. Lung cancer biomarkers have the potential to guide clinical decision-making since they can potentially detect the disease early, measure the risk of developing the disease and the risk of progression, provide accurate information of patient response to a specific treatment and are capable of informing clinicians about the likely outcome of a cancer diagnosis independent of the treatment received. Moreover, lung cancer biomarkers are increasingly linked to specific molecular pathway deregulations and/or cancer pathogenesis and can be used to justify the application of certain therapeutic or interventional strategies.