The purpose of this study is to evaluate the effectiveness and sensitivity of the Varian portal dosimetry (PD) system as a quality assurance (QA) tool for breast intensity-modulated radiation therapy (IMRT) treatment plans.

Four hundred portal dose images from 200 breast cancer patient IMRT treatment plans were analysed. The images were obtained using Varian PortalVision electronic portal imaging devices (EPIDs) on Varian TrueBeam Linacs. Three patient plans were selected, and the multi-leaf collimator (MLC) positions were randomly altered by a mean of 0·5, 1, 1·5 and 2 mm with a standard deviation of 0·1 mm on 50, 75 and 100% of control points. Using the improved/global gamma calculation algorithm with a low-dose threshold of 10% in the EPID, the change in gamma passing rates for 3%/3 mm, 2%/2 mm and 1%/1 mm criterion was analysed as a function of the introduced error. The changes in the dose distributions of clinical target volume and organ at risk due to MLC positioning errors were also analysed.

Symmetric and asymmetric breast or chest wall plan fields are different in delivery as well as in the QA. An average gamma passing rate of 99·8 ± 0·5 is presented for 3%/3 mm symmetric plans and 96·9 ± 4·5 is presented for 3%/3 mm asymmetric plans. An average gamma passing rate of 98·4 ± 4·3 is presented for 2%/2 mm symmetric plans and 89·7 ± 9·5 is presented for 2%/2 mm asymmetric plans. A large-induced error in MLC positioning (2·0 mm, 100% of control points) results in an insignificant change in dose that would be delivered to the patient. However, EPID portal dosimetry is sensitive enough to detect even the slightest change in MLC positioning error (0·5 mm, 50% of control points).

Stricter pre-treatment QA action levels can be established for breast IMRT plans utilising EPID. For improved sensitivity, a multigamma criteria approach is recommended. The PD tool is sensitive enough to detect MLC positioning errors that contribute to even insignificant dose changes.

To analyse the preliminary results of CyberKnife stereotactic radiotherapy (SBRT) boost in primary head and neck cancer patients among Indian population.

A total of nine patients of primary head and neck cancer were treated with CyberKnife SBRT boost after intensity-modulated radiation therapy (IMRT). The median phase 1 IMRT dose was 54 Gy/27 fractions. Histological types included squamous cell carcinoma (n=7) and adenoid cystic carcinoma (n=2). Response was evaluated using positron emission tomography/computed tomography and detailed clinical examination.

As a preliminary analysis with median follow up of 8 months (range: 6–19 months), phase 2 median tumour volume of 16·3 cc and a median dose of 5 Gy per fraction, eight patients had loco-regionally stable disease and one had distant metastasis. With objective assessment five patients had complete response. Treatment was well tolerated with no grade 3 or more acute toxicities directly related to CyberKnife boost.

CyberKnife SBRT boost is an attractive option for primary head and neck cancers especially where disease is in close proximity to critical structures hindering radical dose delivery. Future prospective analysis and optimum assessment of total biological effective dose (BED) in a properly selected case might actually benefit the use of CyberKnife SBRT boost.

This study aimed to determine the radiation dose to the spleen in adjuvant chemoradiotherapy for gastric cancer, resulting in haematological toxicities.

This retrospective analysis of a prospectively maintained database was conducted at a tertiary referral cancer centre. All patients with biopsy-proven non-metastatic gastric adenocarcinoma planned for adjuvant chemoradiotherapy from January 2017 to December 2021 were included. The mean dose to the spleen (Dmean) was estimated and correlated with the development of haematological toxicities.

The mean spleen volume was 186·65 cc. The Dmean to the spleen was 35·35 Gy (20–42 Gy). Grade 3 leukopenia was observed in 67%, grade 4 in 15%, and grade 3 thrombocytopenia was noted in 41% of patients. Radiotherapy (RT) dose > 35·5 Gy to the spleen resulted in ≥ grade 3 leukopenia. RT dose ≥ 36·5 Gy resulted in grade 3 thrombocytopenia. The occurrence of leukopenia and thrombocytopenia was also affected by the location of the primary gastric cancer (higher incidence in distal than in proximal tumours).

The spleen should be considered as an important organs at risk during adjuvant RT for gastric cancer. Dmean to the spleen should be < 35·5 Gy to prevent major haematological toxicities.

Malignant spinal cord compression (MSCC) is a serious condition requiring urgent palliative radiotherapy to alleviate symptoms and avoid permanent paralysis. This audit compares the number of patients treated for MSCC before and during Covid-19, their treatment regimes and 30-day mortality rates to assess if the pandemic affected the treatment and the number of patients referred for palliative radiotherapy.

A retrospective audit was performed (July–December 2019) and 101 patients were treated for MSCC, an average of 17 patients per month. A further audit was undertaken during Covid-19 (March–May 2020) and 36 patients were treated for MSCC, an average of 12 patients per month in this shorter cohort.

The results have demonstrated fewer patients presenting during the pandemic and this may be due to patients not wishing to utilise the National Health Service (NHS) during this time. It also highlighted the need to reduce the treatment duration to minimise hospital attendance and lessen the potential for exposure to Covid-19.

Educating patients at risk of MSCC is essential and all cancer patients should be counselled on symptoms and what to do if they occur. Ensuring clinicians know the warning signs and the referral pathway for MSCC is also key to ensure early presentation and early referral for treatment.

Educational gamification is the introduction of game elements into other activities such as teaching and learning. VERT is a tool in therapeutic radiography that lends itself to gamification as it allows students to experiment and learn at no risk to the patient. The aim of this study was to evaluate the use of a gamified simulation using competitive task elements.

A total of 78 participants undertook the study which involved a demonstration and practice patient set-up followed by an unassisted timed patient set-up. Once complete the students score was added to a leaderboard.

Results show very good students’ feedback on the simulation elements, and that skills were transferable and would improve clinical performance. Gender differences were observed in the competitive feedback on two items, satisfaction from competing and competition encouraging performance.

Overall the competitive aspect was viewed positively by students, although females appeared to enjoy the competitive aspects less than the male students, deriving significantly less satisfaction from the competitive element of the simulation. Despite the emphasis on teamwork within the profession, competitive gamification does appear to have a role within the undergraduate curriculum if carried out correctly.

For chest wall irradiation in breast cancer patients, three-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiotherapy (IMRT) have made tremendous changes in treatment delivery.

The purpose of this study is to compare the dosimetric parameters in IMRT and 3DCRT plans.

IMRT and 3DCRT plans were generated for 25 randomly selected postmastectomy breast cancer patients. The prescribed dose (PD) was 50 Gray (Gy) in 25 fractions (#) at the rate of 2 Gy/# with 5#/week. Dose volume histogram was evaluated for planning target volume (PTV) coverage and dose to organs at risk (OARs). All the dosimetric parameters were compared using unpaired student’s t-test.

PTV coverage was significantly better in IMRT, although the 90% of PTV was well covered by 90% of PD in all plans by both the techniques. Homogeneity index and conformity index were better in IMRT. V5 Gy and Dmean of contralateral lung, contralateral breast and heart (right side chest wall cases) were found to be lesser in 3DCRT compared with that in IMRT. However, there was no significant difference in V20 Gy of ipsilateral lung and V25 Gy of heart (left side chest wall cases) in all the plans by both the techniques.

Adequate target coverage was achieved by both the techniques, however, dose to OARs were lesser in 3DCRT plans as compared with that in IMRT plans. Thus, it can be concluded that 3DCRT is as efficient as IMRT for the chest wall irradiation.

The aim of this study was to find the optimal radiotherapy (RT) method using three-dimensional (3D) conformal RT (CRT), physical wedge-based CRT (WB-CRT) and dynamic intensity-modulated RT (D-IMRT) techniques for stomach cancer.

Ten patients with gastric cancer were selected for this study. For each patient, three different treatment plans were generated. 3D-CRT, WB-CRT and IMRT plans were evaluated in terms of dosimetry. Treatment plans were compared with respect to the planning target volume and organs at risk (OARs) volumes including right and left kidney doses (V13, V20 and V28), heart mean and maximum doses, spinal cord maximum doses, dose homogeneity index, conformity index (CI), delivery time and the monitor unit counts for the treatment. Statistical analysis was performed using the SPSS (Statistical Package for the Social Sciences) v25.1 software (IBM Inc., Chicago, IL, USA).

In stomach plans, IMRT showed a significantly lower dose for the left and right kidneys than that of WB-CRT or 3D-CRT (p < 0·05). Compared with WB-CRT or 3D-CRT, IMRT reduced the V28, V20, V13 and mean dose to bilateral kidneys (p < 0·05). IMRT plans indicated better dosimetry for at the Dmean of the liver and heart. Concerning the calculated CI, values for IMRT plans gave significant results than other plans (p < 0·05).

IMRT plans provided better protection for the kidneys, liver, heart and spinal cord. For the treatment of stomach cancer, considering the dose to the OARs, IMRT appears to be the most superior technique.

The incidence of venous air embolism (VAE) during and following diagnostic and interventional radiographic procedures utilizing contrast media has been well documented in the literature. However to date a case report of a venous air embolism occurring within an outpatient healthcare facility during a contrast enhanced computer tomography radiation therapy planning procedure remains under reported.

Healthcare professionals must remain alerted to the fact that iatrogenic VAE may occur unexpectedly during and following diagnostic and interventional radiographic procedures utilizing the injection of contrast media. The action by all healthcare professionals to implement rapid and clear acute care guidelines will increase the probability of the patient recovering from the event.

A review of the aetiology and associated pathophysiology of VAE is provided. This is followed by a detailed case report of the occurrence of a non-fatal VAE event (patient consent was obtained and the consent form template was reviewed by a Research Ethics Board).

We conclude with a discussion of quality assurance recommendations that should be considered for implementation in an outpatient facility setting that is performing contrast enhanced computer tomography diagnostic, interventional or radiation therapy planning radiographic procedures.

With recent technological advances in image-guided radiation therapy (IGRT), through cone-beam computed tomography (CBCT), more image-related clinical information is being collected, at more frequent intervals throughout the treatment course. As radiation therapy (RT) programmes further develop IGRT technology, the aim of this study is to assess whether the distribution and communication of professional responsibilities is evolving to ensure appropriate use of the technology.

Radiation therapists practicing at any of the 14 Ontario RT centres were sent an electronic survey (n = 400). Closed-ended quantitative items addressed perceptions regarding policies, comfort, and professional responsibility in addressing CBCT concerns. Focus was on gynaecological, lung, head and neck (H&N) disease sites. Options for qualitative comments and explanations were included where appropriate.

Seventy-nine surveys were submitted. Respondents from 12/14 (85·7%) centres used CBCT for at least one of three disease sites, most commonly on a daily basis. Five of these centres (41·7%) did not require radiation oncologist CBCT review, with others requiring it Day 1 or weekly. Potential CBCT observations of concern were grouped as set-up issues, tumour changes, organ-at-risk (OAR) changes, contour changes and ancillary findings (especially lung and airway changes). Respondents believed they consulted another professional about a CBCT in 20·2% of H&N patients, 19·6% of lung patients and 9·7% of gynaecological patients. The level of comfort in doing so varied from 77·0% for H&N to 89·5% for lung. Respondents were most likely to believe themselves responsible for changes in OARs (92·2% believing themselves responsible), and least likely for ancillary findings (62·7%).

Through preliminary insight from Ontario therapists, a degree of inconsistency is apparent between perceptions, practices and assigned roles in the management of CBCT information. Clear definition of the scope and nature of therapists’ responsibility for interpreting and addressing changes on CBCT images should be developed within each centre.

To verify the accuracy of two common absorbed dose calculation algorithms in comparison to Monte Carlo (MC) simulation for the planning of the pituitary adenoma radiation treatment.

After validation of Linac's head modelling by MC in water phantom, it was verified in Rando phantom as a heterogeneous medium for pituitary gland irradiation. Then, equivalent tissue-air ratio (ETAR) and collapsed cone convolution (CCC) algorithms were compared for a conventional three small non-coplanar field technique. This technique uses 30 degree physical wedge and 18 MV photon beams.

Dose distribution findings showed significant difference between ETAR and CCC of delivered dose in pituitary irradiation. The differences between MC and dose calculation algorithms were 6.40 ± 3.44% for CCC and 10.36 ± 4.37% for ETAR. None of the algorithms could predict actual dose in air cavity areas in comparison to the MC method.

Difference between calculation and true dose value affects radiation treatment outcome and normal tissue complication probability. It is of prime concern to select appropriate treatment planning system according to our clinical situation. It is further emphasised that MC can be the method of choice for clinical dose calculation algorithms verification.

Prostate cancer is the most commonly diagnosed cancer in men and it is responsible for about 10% of all cancer mortality in Canadian men. The current ‘gold standard’ for the diagnosis of prostate cancer is a prostate biopsy and the decision on when to biopsy a patient with non-suspicious Digital Rectal Examination (DRE) result and total prostate specific antigen (tPSA) of 4–10 ng/ml can be challenging. In order to shift the treatment paradigm of prostate cancer toward more personalised and targeted therapy, there is the need for a clear system that makes its detection binary so as to decrease the rate of inaccurate detections. Therefore in recent years, there have been several investigations into the development of various biomarkers with high sensitivity and specificity for screening, early detection and personalised patient-specific targeted medicine from diagnosis to treatment of the disease.

This paper reports on nine currently available clinical biomarkers used in screening for early detection and diagnosis, to reduce the number of unnecessary biopsies, in risk assessment of aggressive disease and in monitoring treatment response of prostate cancer.

Current clinical prostate cancer biomarkers have the potential for a personalised risk assessment of aggressive disease and the risk of developing distant metastatic disease and have been proven to be useful tools to guide clinicians in personalised patient-specific targeted treatment and in the shared decision making between patients and their physicians regarding prostate biopsy and treatment. Using biomarkers to select patients with a significant probability of aggressive prostate cancer would potentially avoid premature death from the disease, while at the same time would safely preclude patients who do not require unnecessary invasive intervention.

The virtual environment for radiotherapy training (VERT) helps students to gain technical skills and understanding of 3D anatomy and dosimetry. It has potential as a tool for treatment plan evaluation, although little formal evidence currently supports this.

This paper reports findings from a plan evaluation workshop that facilitated comparison of VERT plan evaluation tools with those provided by conventional treatment planning software (TPS).

Students on a pre-registration Post-Graduate Diploma in Radiotherapy worked in small groups evaluating lung plans using both VERT and Eclipse TPS tools. All students were invited to provide ratings concerning how helpful each modality was for a range of evaluation parameters and preferences for use.

Most students (11 out of 14) found the session useful and expressed a desire to use VERT in future plan evaluation. The TPS was perceived to be more helpful with constraint-based evaluation while VERT was more helpful with evaluating plans for clinical set-up and delivery (p < 0·001).

Student therapeutic radiographers found VERT to be helpful as a plan evaluation tool alongside standard TPS tools, in particular for clinical set-up and delivery aspects of planning. Future work is ongoing to identify the specific impact of VERT as a plan evaluation tool for both students and qualified planners.

Superficial X-ray therapy units are used for the treatment of certain types of skin cancer and some severe dermatological conditions. The performance assessment and beam characteristics of the superficial unit are very important to ensure accurate dose delivery during patient treatment. Both experimental measurements and Monte Carlo calculations can be used for this purpose.

This study aims to investigate whether it is possible to reproduce experimentally measured data for the XSTRAHL 150 superficial X-ray unit with simulations using the BEAMnrc Monte Carlo code.

The experimental procedure applied in this study included the following: experimental measurements of different X-ray spectra, half-value layers, percentage depth dose and beam profiles. Monte Carlo modelling of the XSTRAHL 150 unit was performed with the BEAMnrc code. The validity of the model was checked by comparing the theoretical calculations with experimental measurements.

There was good agreement (∼1%) between experimentally measured and simulated X-ray spectra. Results of half-value layers obtained from simulated and measured spectra showed that there was a maximum of 3·6% difference between BEAMnrc and measurements and a minimum of 2·3%. In addition, simulated percentage depth dose and profile curves have been compared against experimental measurements and show good agreement (within 2% for the depth dose curves and 3–5% for beam profile curves, depending on the applicator size).

The results of this study provide information about particles’ interaction in different kilovoltage and filter combinations. This information is useful for X-ray tube design and development of new target/filter combinations to improve beam quality in superficial X-ray radiotherapy. The data presented here may provide a base for comparison and a reference for other or potential new users of the XSTRAHL 150 X-ray unit.