To investigate the dosimetric advantage of quasi-continuous couch motion-enabled trajectory modulated arc radiotherapy therapy (TMAT) over the coplanar tangential partial arcs volumetric modulated arc radiotherapy (VMAT) for treating left breast and chest wall patients.

Treatment plans of 43 patients who received radiotherapy for left breast (17) or for left chest wall (26) using coplanar partial tangential arcs VMAT (reference plan) were considered for this study. For each patient, in addition to the treatment plan, a TMAT plan was also generated using quasi-continuous couch rotation. The TMAT plan consisted of original two 30° tangential arc beams and two supplementary beams having a couch rotation of ±10°, ±20° and ±30°, respectively. The difference in PTV volume coverage (PTV V95%) between TMAT plan and VMAT plan was calculated for all the cases and normalised to the plan’s prescription dose. Similarly, differences in PTV_V105% and several dose-volume parameters related to organs at risk (OAR) were also computed and tabulated.

TMAT shows an increment in the PTV dose coverage V95% with respect to reference plan by 4·7±2·5% when averaged overall prescription dose levels. Mean PTV dose (averaged overall prescription levels) for reference and TMAT plan was 4638·6±423·8 and 4793·5±447·2 cGy, respectively, and statistically insignificant (p=0·06). However mean PTV_V105% values for TMAT and for reference plans were 6·7±4·8 and 7·2±5·2%, respectively, and were not statistically different (p=0·85). Mean heart dose in TMAT was less than in VMAT plans, but not significantly. As regarding D1% to heart, TMAT plan was again found to be better with a mean difference of 137·1 cGy over VMAT plan. Other parameters evaluated were: mean dose and D1% to contralateral breast, and V20 Gy and V5 Gy for lung.

TMAT plans were found to be better than VMAT plans in terms of PTV coverage and D1% for heart. For evaluated dose parameters apart from PTV coverage and D1% to the heart, no significant differences were observed. Thus, TMAT plans yielded better dose distribution in terms of PTV dose coverage, hot spots and OAR doses.

To explore student therapeutic radiographers’ understanding of obesity and cancer and to identify if student therapeutic radiographers believe that radiographers should have a role within weight management.

This study used a self-completed online questionnaire (google forms) to collect data from Radiotherapy and Oncology students, studying at one Higher Education Institution, to gain an understanding of their current knowledge of weight management. A retrospective margin of error calculation was carried out, showing a 9% margin of error with a 90% confidence level.

In total 57 responses were received, n = 50 BSc students and n = 7 pre-registration MSc students. Three key barriers to openly discussing weight loss management with service users emerged from the questionnaire data; these were a lack of time, lack of clear guidelines and lack of confidence. These barriers could potentially be addressed by improving education and training, making it easier for therapeutic radiographers to openly discuss weight management with service users.

Awareness of guidelines was suboptimal, with 82% (n = 47) of respondents unaware of any guidelines. In addition to this, the majority of students identified a lack of confidence as a barrier to them providing weight management advice. Despite this, 54·4% of respondents agreed that radiographers should have a role in providing weight management advice, with 22·2% of respondents being unsure. Findings suggest that behaviour change is required amounts both students and staff members, so that healthcare professionals are more inclined to have healthy weight management discussions. Perhaps more specialist roles need to be developed, so that healthy weight management discussions can become a norm.

The combination of radiation therapy and chemotherapy is rooted in its ability to help achieve locoregional and systemic control, therefore increasing the overall disease-free survival of patients. Understanding the mechanistic actions of cytotoxic agents and their targets on the cell cycle, as well as the governing pharmacokinetic principles can improve treatment delivery. The adjuvant treatment setting can overcome barriers such as hypoxia and genetically driven treatment resistance.

The purpose of this review is to present theoretical frameworks behind the chemoradiation paradigm and to describe current chemoradiation practices in radiation oncology.

A review was conducted using the US National Library of Medicine, National Institutes of Health database (PubMed) using the following search keywords: chemoradiation, spatial cooperation, chemotherapeutic agents, pharmacokinetics, anti-vascular agents, tumour vasculature and tumour hypoxia.

Current research has reported several rationales for the beneficial combination of radiation and chemotherapy to eradicate oncological diseases. Mechanisms of action and biological approaches are showing that concurrent treatments, as well as novel agents such as anti-vascular and anti-angiogenic agents may benefit improved treatment outcomes by reducing micro hypoxic environments in tumours. In addition, chemotherapy administered in tandem with radiation enhances cell-killing effects by targeting the cell cycle.

Head and neck cancer (HNC) accounts for 5% of all new cancer cases and most were locally advanced. Positron emission tomography/computed tomography (PET/CT) in radiotherapy practice in locally advanced head and neck squamous cell carcinoma (HNSCC) is being used in staging and proper contouring. Proper staging is essential for accurate treatment decision.

This is a prospective phase II study conducted as a single institute centre to evaluate the role of PET/CT-treatment in staging, contouring and response evaluation of 30 patients with locally advanced HNSCC in contrast to CT scan. Our cases did not undergo radical surgery for the primary tumour, and biopsy was taken with PET/CT post-treatment to evaluate response.

Median age of patients was 49·4 years (minimum age of 32 years and maximum of 68 years). Males were predominant 22 (73·3%). Nasopharynx was the predominant site 16/30 (53·3%). PET/CT changed the overall staging in 40% of the patients (upstaged in 36·7% and downstaged in 3·3%). Gross tumour volume (GTV) of PET/CT was smaller in 23 patients (76·7%) and larger in 5 (16·7%) than the GTV of conventional CT, whereas GTV of lymph nodes of PET/CT was larger in 20 patients (67·7%) and smaller in 4 (13·3%). PET/CT study detected bone metastasis in two nasopharyngeal carcinoma patients and two cases of 2nd primary tumours which were not detected using conventional CT. The Cox-regression model showed that the median standardised uptake volume (SUV) of the initial tumour had been a dependent predictor of death in patients with HNSCC (p-value = 0·033) where the risk of death was 0·725 times among patients with high SUV of the initial tumour. Consequently, the size of GTV of the tumour was significant in the prediction of death (p = 0·018).

18F-FDG-PET/CT is useful for staging, radiotherapy delineation as well as aiding proper decision making, in addition to assessment of treatment response in HNSCC patients.

Orbital metastases lead to many distressful symptoms.

A case-report of a 44-year-old woman with a melanoma metastasis in the orbital cavity, is reported. A patient presented with headache, proptosis and diplopia. The stereotactic radiotherapy of 19.5 Gy in three fractions using CyberKnife was performed. Follow-up examination 7 months later revealed satisfactory local control of the tumour, alleviation of orbital symptoms with no negative impact on visual function.

Stereotactic radiotherapy seems to be a safe and effective treatment of orbital metastases from melanoma.

The aim of this study is to investigate the impact of anatomical changes in prostate cancer patients on the target coverage when using 6 MV beams-VMAT therapy and to propose strategies that allow us to evaluate the dose or correct it by normalization without having to perform a new simulation.

Ten patients of high-risk prostate cancer were chosen for the study. All test plans were delivered using the same isocenter and monitor units as the original plan and compared against the original unedited plan. The expansion and contraction of body contours due to size changes was mimicked by increasing and decreasing the body contour with depths of −2, −1·5, …, 1·5, 2 cm, in the anterior, and both lateral directions of the patient. A total of 90 plans were evaluated, 9 for each patient. Dose-volume histogram statistics were extracted from each plan and normalized to prescription dose.

Weight changes resulted in considerable dose modifications to the target and critical structures. Plans were found to be varied with 2·9% ± 0·3% per cm SSD change for VMAT treatment with a correlation index close to one. Therefore, doses variations were linear to the changes of depth. Gamma index evaluation was performed for the 10 renormalized plans. All of them passed criteria of 3%/3 mm in at least 98.2% of points. Eight of them passed criteria in 99% points. Gamma index 4%/4 mm passed 100% points in all patients for the chosen region of interest.

The dosimetry estimation presented in this study shows important data for the radiation oncology staff to justify whether a CT rescan is necessary or not when a patient experiences weight changes during treatment. Based on the results of our study, discrepancies between real dose and planned dose were >5% for 1·7 cm of difference in external contour in the anterior and both lateral directions of the patient.

CyberKnife is the most advanced form of stereotactic body radiotherapy (SBRT) system that uses a robotic arm to deliver highly focused beams of radiation; however, a limitation is that it only irradiates from ceiling to floor direction. In patients with posterior lungs tumour who are positioned supine, normal lung tissue may suffer undesirable radiation injuries. This study compares the treatment planning between the prone set-up and the supine set-up for lung cancer in CyberKnife SBRT to decrease normal lung dose to avoid radiation side effects.

A human phantom was used to generate 108 plans (54 for prone and 54 for supine) using the CyberKnife planning platform. The supine and prone plans were compared in terms of the dosimetric characteristics, delivery efficiency and plan efficiency.

For posterior targets, the area of low-dose exposure to normal lungs was smaller in the prone set-up than in the supine set-up. V10 of the lungs was 7·53% and 10·47% (p < 0·001) in the anterior region, and 10·78% and 8·03% (p < 0·001) in the posterior region in the supine and prone set-up plans, respectively.

The comparison between the prone set-up and the supine set-up was investigated with regard to target coverage and dose to organs at risk. Our results may be deployed in CyberKnife treatment planning to monitor normal tissue dose by considering patient positioning. This may assist in the design of better treatment plans and prevention of symptomatic radiation pneumonitis in lung cancer patients.

The aim of this study was to evaluate clinical efficacy and radiobiological outcome of intensity-modulated radiation therapy (IMRT) modalities using various collimator angles and non-coplanar fields for nasopharyngeal cancer (NPC).

A 70-Gy planning target volume dose was administered for 30 NPC patients referred for IMRT. Standard IMRT plans were constructed based on the target and organs at risk (OARs) volume; and dose constraints recommended by Radiation Therapy Oncology Group (RTOG). Using various collimator angles and non-coplanar fields, 11 different additional IMRT protocols were investigated. Homogeneity indexes (HIs) and conformation numbers (CNs) were calculated. Poisson and relative seriality models were utilised for estimating tumour control probability (TCP) and normal tissue complication probabilities (NTCPs), respectively.

Various collimator angles and non-coplanar fields had no significant effect on HI, CN and TCP, while significant effects were noted for some OARs, with a maximum mean dose (Dmax). No significant differences were observed among the calculated NTCPs of all the IMRT protocols. However, the protocol with 10° collimator angle (for five fields out of seven) and 8° couch angle had the lowest NTCP. Furthermore, the standard and some of non-coplanar IMRT protocols led to the reduction in OARs Dmax.

Using appropriate standard/non-coplanar IMRT protocols for NPC treatment could potentially reduce the dose to the OARs and the probability of inducing secondary cancer in patients.

The purpose of this study was to determine the dose enhancement factor (DEF) of gold nanoparticles in a dosimeter gel and construct percentage depth dose curves, using the Optical CT system and the Monte Carlo simulation model, to determine the effect of increasing the dose caused by increasing the concentration of gold nanoparticles at depths in the gel.

The Magic-f Gel was made based on the relevant protocol in the physics lab. To determine the amount of the increase in the absorbed dose, the gold nanoparticles were added to the gel and irradiated. An increase in the dose after adding nanoparticles to the gel vials was estimated both with the Optical CT system and by the Monte Carlo simulation method.

Dose enhancement curves for doses of 2, 4 and 6 Gy were prepared for gel vials without adding nanoparticles, and nanoparticle gels at concentrations 0·17, 3 and 6 mM. Also, the DEF was estimated. For the 0·17 mM molar gel, the DEF for 2, 4 and 6 Gy was 0·7, 0·743 and 0·801, respectively. For the 3 mM gel, it was 1·98, 2·5 and 2·2, and for the 6 mM gel, it was 37·4, 4·24 and 4·71, respectively.

The enhancement of the dose after adding gold nanoparticles was confirmed both by experimental data and by simulation data.

Radiation therapy (RT), in combination with chemotherapy, is the mainstay in the treatment for locally advanced oropharyngeal cancer. We analysed the tumour response and the toxicity profiles in patients having locally advanced oropharyngeal cancers receiving hypofractionated intensity-modulated radiation therapy (IMRT) and concurrent chemotherapy with Cisplatin investigating the feasibility and radiobiological efficacy of the regimen, along with its use as a resource-sparing alternative for a high-volume centre.

The records of 41 eligible patients with locally advanced squamous cell carcinoma of oropharynx, registered from September 2015 to April 2017, treated with hypofractionated IMRT with concurrent Cisplatin, were analysed from the hospital database. Patients received concurrent chemo-radiation with 2 cycles of 3-weekly cisplatin on day 1 and day 22 along with hypofractionated IMRT, 55 Gy delivered in 20 fractions over 4 weeks. Patients were observed for any radiation reaction or chemotherapy toxicity at least once a week during the course of radiation therapy.

Twenty-nine patients (70·7%) achieved complete response and remaining 12 showed partial response. Acute grade 3 toxicity was observed mostly in the form of oral mucositis and radiation dermatitis. Both grade 3 oral mucositis and radiation dermatitis were seen in 15 patients (36·6%) and 7 patients (17%), respectively. The most common late toxicities were dysphagia and dry mouth. Twenty-five patients (61%) completed the overall treatment within 4 weeks’ duration.

This hypofractionated regimen is feasible and was associated with tolerable acute and late morbidity and satisfactory locoregional response. Larger prospective, multi- institutional studies examining similar schedules may be undertaken to establish this as a standard practice, particularly for a high-volume centre.

To analyse the presentation, diagnosis and patterns of care of extraosseous Ewing sarcoma treated at our institution between 2008 and 2018.

Electronic medical records of extraosseous Ewing sarcoma patients treated at our institution between January 2008 and April 2018 were reviewed. Kaplan–Meier curves were plotted to assess the overall and disease-free survival with 95% confidence intervals. A univariate analysis was carried out to assess the impact of variables such as surgical excision, completeness of surgery, completeness of chemotherapy and addition of radiation therapy on the survivorship.

The records of 65 patients treated at our institution were available for review. The mean age was 26·4 years. The most frequent sites of extraosseous Ewing tumour were kidney—9/65 (13·8%) and brain—10/65 (15·4%). Sixteen (24·6%) patients presented with inoperable/metastatic disease at diagnosis. The other 49 (75·4%) had localised disease at presentation. The median overall survival of the 49 non-metastatic patients was 46 months, and the disease-free survival was 45 months.

Extraosseous Ewing sarcoma is a rare and aggressive tumour diagnosed by molecular techniques. Multi-modality treatment including surgical resection with wide margins, adjuvant radiation when indicated and completion of systemic chemotherapy results in optimum outcomes.

A comprehensive analysing method has been required since long in the field of radiotherapy. The basic purpose of all techniques has been to deliver the prescribed dose safely to the target volume containing tumour and as well as to reduce dose to organs at risk (OARs). The detailed comparison between different treatment techniques is very difficult and inexplicit as well. The gradual improvement in imaging software has made easy to users to assess spatial arrangement of tumour, critical organs and isodose lines in the form of a single 3D representation that can be observed from all angles. The conformity index (CI) alone cannot provide practical information about treatment plans as it is a single isodose line quantity.

The aim of this study was to develop a new method to assess the degree of damage numerically for OARs along with CI assessment for the target.

The radiotherapy plans of 30 patients of different sites, diagnosed as cancer, were selected for this study irrespective of gender. Out of 30 cases, 8 plans were of head and neck, 2 were of glyoblastoma (GBM), 10 were of pelvis, 5 were of left breast and other 5 were of oesophagus cancer. The mean age was 42 years ranging from 31 to 72 years. Patient’s consents were taken before starting the treatment and carried out this research. Risk factor (RF) for OARs depends on volume of irradiation (VVOI), total volume of the organ (VTVO) and tolerance dose (DTDO). All radiotherapy plans (Intensity Modulated Radiotherapy (IMRT) and Volumetric Modulated Arc Therapy (VMAT)) were generated using eclipse planning system, version 11.0 (Varian Medical System, Palo Alto, California, USA).

The formula developed to assess degree of damage of OARs including CI of the target is risk factor conformity index (RFC) = CI + RF. In head and neck cases, for right parotid, the maximum value of RF is 1·50 and minimum value is observed as 0·97. Optic nerve, brainstem and spinal cord are completely safe as their RF values are found to be 0 on RF scale.

RFC is a comprehensive evaluation tool encompassing a wider range of clinically relevant parameters, isodose volumes and tolerance dose of OARs. It is an advance analysing method to check both the qualitative and quantitative nature of a conformal plan, and at the same time, it assesses the degree of damage of OARs.

If RF ≥ 1, then OAR will be completely damaged as a result of irradiation.

If RF = 0, then OAR will remain safe totally during the course of irradiation.

Total body irradiation (TBI) is an external radiotherapy technique in which the whole body including the superficial regions is required to receive the therapeutic dose. The purpose of this study is to evaluate the received surface dose during TBI technique.

The anterior/posterior (AP/PA) TBI was implemented with 18-MV photon beam at 312-cm treatment distance for human-like phantom. The GAFCHROMIC-EBT3 films were used for superficial dose measurements.

The percentage of surface-absorbed dose relative to the prescription point for 8 points of measurements was between 102·78–121·48% and 104·51–127·43% at 5 and 10 mm depth, respectively. In the chest wall region due to the presence of lung blocks, the absorbed dose was below the acceptable level, so an electron boost was required to increase the chest wall absorbed dose.

According to the results, the implemented technique was able to deliver sufficient dose to the shallow surface of phantom’s body.

In recent years, there has been a spectacular development in nanomedicine field with new nanoparticles for diagnosis and cancer therapy. Although most researchers have been always interested in gold nanoparticles (GNPs)

In the present work we present a comparison between the use of bio-nanomaterials in proton therapy.

Consequently, our results show that platinum nanoparticles (PtNPs) present an interesting advantages comparing with GNPs and silver nanoparticles. On the other hand, the use of PtNPs facilitates in a considerable way the proton therapy.

To study 2D and 3D dosimetric values for bladder and rectum, and the influence of bladder volume on bladder dose in high dose rate (HDR) intracavitary brachytherapy (ICBT). The large patient data incorporated in this study would better represent the inherent variations in many parameters affecting dosimetry in HDR-ICBT.

We prospectively collected data for 103 consecutive cervical cancer patients (over 310 HDR fractions) undergoing CT-based HDR-ICBT at our centre. Correlation among bladder and rectum maximum volume doses and corresponding International Commission on Radiation Units and Measurement (ICRU) point doses were estimated and analysed. Impact of bladder volume on bladder maximum dose was assessed.

The ICRU point doses to bladder and rectum varied from the volumetric doses to these organs. Further, bladder volume poorly correlated with bladder maximum dose for volume variations encountered in the clinical practice at our centre.

ICRU point doses to bladder and rectum are less likely to correlate with long-term toxicities to these organs. Further, in clinical practice where inter-fraction bladder volume does not vary widely there is no correlation between bladder volume and bladder dose.