The incidence of breast cancer has surpassed cervical cancer in India and it has now become the most common cancer in women. Multiple randomised studies have reported low α/β value in the range of 3–4 for breast cancer, which predict a potential radiobiological advantage for hypofractionated radiotherapy resulting in such schedules becoming standard in many centers with reduction in overall treatment time. Volumetric modulated arc therapy (VMAT) is a novel technique of delivering radiotherapy that reduces treatment delivery time, requires less monitor units (MU) and offers good conformity. The mean dose to normal tissue may be minimised using this technique although there will be inferior sparing if we consider the low-dose volume such as V5, the effect of which is not quantifiable yet.

Reporting acute toxicity, cosmetic effects, and quality of life in patients of early breast cancer treated with adjuvant hypofractionated VMAT with SIB.

The records of 44 patients registered at the hospital between August 2014 and December 2015 were included in this analysis. Acute toxicities were analysed using CTCAE v4.03. Cosmetic outcomes were assessed using Harvard scale, while quality of life outcomes were assessed using EORTC scales and Health Related quality of life (HRQOL) questionnaires (QLQ-C30 and QLQ-BR23).

No grade ≥2 skin toxicities were recorded. Breast pain was recorded as Grade 1 in 13·8% patients and Grade 1 fatigue in 18·2%. The maximum haematological abnormality grade recorded was Grade 1. Cosmesis was assessed at the baseline, 6 months, 1 year and 2 years. A total of 88·6% of the patients had an Excellent or good cosmesis at the baseline, which was similar even at 6 months, at 88·7%, improved further at 1 year to 90·9%. At 6 months post radiotherapy, high functional scale QOL scores were noted.

The technique is associated with minimum acute toxicity, good to excellent cosmesis and acceptable quality of life.

To establish whether the use of a passive or active technique of planning target volume (PTV) definition and treatment methods for non-small cell lung cancer (NSCLC) deliver the most effective results. This literature review assesses the advantages and disadvantages in recent studies of each, while assessing the validity of the two approaches for planning and treatment.

A systematic review of literature focusing on the planning and treatment of radiation therapy to NSCLC tumours. Different approaches which have been published in recent articles are subjected to critical appraisal in order to determine their relative efficacy.

Free-breathing (FB) is the optimal method to perform planning scans for patients and departments, as it involves no significant increase in cost, workload or education. Maximum intensity projection (MIP) is the fastest form of delineation, however it is noted to be less accurate than the ten-phase overlap approach for computed tomography (CT). Although gating has proven to reduce margins and facilitate sparing of organs at risk, treatment times can be longer and planning time can be as much as 15 times higher for intensity modulated radiation therapy (IMRT). This raises issues with patient comfort and stabilisation, impacting on the chance of geometric miss. Stereotactic treatments can take up to 3 hours to treat, along with increases in planning and treatment, as well as the additional hardware, software and training required.

Four-dimensional computed tomography (4DCT) is superior to 3DCT, with the passive FB approach for PTV delineation and treatment optimal. Departments should use a combination of MIP with visual confirmation ensuring coverage for stage 1 disease. Stages 2–3 should be delineated using ten-phases overlaid. Stereotactic and gated treatments for early stage disease should be used accordingly; FB-IMRT is optimal for latter stage disease.

The purpose of this study was to develop the patient-specific quality control (QC) process by most commonly used dosimeters in Bangladesh and recommend a suitable passing rate for QC, irrespective of the dosimetric tools used.

Intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) plans of five head-and-neck (HN) and five prostate patients were selected for the patient-specific QC. These plans were generated using the Eclipse TPS v11·0 (Varian Medical Systems, Inc., Palo Alto, CA, USA) 6 MV X-ray from a Varian TrueBeam linear accelerator (Varian Medical Systems, Inc.) for each case. Each IMRT and VMAT plans were measured by two-dimensional (2D) ion chamber arrays (I’matriXX) and electronic portal imaging devices (EPID), respectively. The passing rates of the dosimetric tools were calculated using criteria of 3%/3 mm.

The average passing rates (±SD) of I’matriXX for prostate and HN were 97·9±0·76 and 98·88±0·24, respectively. For VMAT verification, the average passing rates of EPID for prostate for arc1 and arc2 were 96·15±0·49 and 97·8±0·70, respectively; similarly, for HN the rates were 97·85±0·63 and 97·2±0·56, respectively.

The results showed that both the dosimeters can be used in patient-specific QC, although the EPID-based IMRT and VMAT QC is more advantageous in terms of time-saving and ease of use. Hence, for patient-specific QC, one can use the ion chamber arrays (I’matriXX) or EPID in hospital, but the systems need to be cross-checked.

It is unclear whether body mass index (BMI) is a useful measurement for examining prostate motion. Patient’s subcutaneous adipose tissue thickness (SAT) and weight has been shown to correlate with prostate shifts in the left/right direction. We sought to analyse the relationship between BMI and interfraction prostate movement in order to determine planning target volume (PTV) margins based on patient BMI.

In all, 38 prostate cancer patients with three implanted gold fiducial markers in their prostate were recruited. Height, mass and SAT were measured, and the extent of interfraction prostate movement in the left/right, superior/inferior and anterior/posterior directions was recorded during each daily fiducial marker-based image-guided radiotherapy treatment. Mean corrective shift in each direction for each patient, along with BMI values, were calculated.

The median BMI value was 28·4 kg/m2 (range 21·4–44·7). Pearson’s product-moment correlation analysis showed no significant relationship between BMI, mass or SAT and the extent of prostate movement in any direction. Linear regression analysis also showed no relationship between any of the patient variables and the extent of prostate movement in any direction (BMI: R2=0·006 (ρ=0·65), 0·002 (ρ=0·80) and 0·001 (ρ=0·86); mass: R2=0·001 (ρ=0·87), 0·010 (ρ=0·54) and 0·000 (ρ=0·99); SAT: R2=0·012 (ρ=0·51), 0·013 (ρ=0·50) and 0·047 (ρ=0·19) for shifts in the X, Y and Z axis, respectively). Patients were grouped according to BMI, as BMI<30 (n=25, 65·8%) and BMI≥30 (n=13, 34·2%). A two-tailed t-test showed no significant difference between the mean prostate shifts for the two groups in any direction (ρ=0·320, 0·839 and 0·325 for shifts in the X, Y and Z axis, respectively).

BMI is not a useful parameter for determining individualised PTV margins. Gold fiducial marker insertion should be used as standard to improve treatment accuracy.

To quantify the effect of breathing motion on post-mastectomy radiotherapy with three-dimensional (3D) tangents and intensity-modulated radiotherapy (IMRT)

Patients trained for breath-hold underwent routine free breathing (FB) computed tomography (CT) simulation for radiotherapy as well as additional CT scans with breath held at the end of normal inspiration (NI scan) and expiration (NE scan) for study. The FB scan was used to develop both tangents and IMRT plans. To simulate breathing, each plan was copied and applied on NI and NE scans. The respiratory parameters of the patients as well as the dosimetric data with both the plans were analysed.

Breathing motion resulted in mean fall in target coverage (V95) with IMRT by more than 5% when compared with tangents, and this effect significantly correlated with higher tidal volume. There was also a decrease in the mean target minimal dose by 20–25% with IMRT when compared with 10–12% with tangents, attributable to breathing motion. However, the cardiac dose crossed the limit (V25<10%) with breathing in the 3D tangents plan.

Dosimetric coverage of the chest wall is sensitive to breathing motion for the IMRT technique when compared with standard tangents, especially in patients with large tidal volume.

The study aimed to evaluate the shear bond strength (SBS) of metal brackets and adhesive properties of bonded irradiated and non-irradiated teeth.

Sixty-six extracted premolar samples were randomly divided into three groups—(a) Control group consisting of 22 non-irradiated, non-aged teeth (Group 1), (b) 22 non-irradiated, aged samples (Group 2) and (c) 22 irradiated, aged samples (Group 3). Irradiation was done using gamma irradiation with a fractionated dose of 60 Gy for 5 consecutive days per week over 6 weeks. Metal brackets were bonded on all samples with light cure adhesive and subjected to SBS test using universal testing machine. The samples were assessed under the scanning electron microscope to check for the adhesive remnant index (ARI) and tag depth.

There was a statistically significant decrease in the mean SBS of the irradiated samples compared to the non-irradiated teeth. The non-irradiated, aged samples showed a majority of ARI scoring 1 and 2. Whereas, the irradiated samples showed ARI scoring 2 and 3. Approximately, 77·3% of the non-irradiated samples showed no adhesive present on the tooth surface, and 27·2% of the irradiated samples had more than 50% adhesive present on the enamel surface.

There is a statistically significant decrease in SBS of irradiated enamel compared to that of non-irradiated teeth. However, the SBS observed in the three groups was well above the ideal SBS for orthodontic bonding, that is, 5·6–6·8 MPa. The adhesive remnant was found on all samples of the irradiated group. Deeper adhesive resin tags were found in the irradiated group in the resin–enamel interface.

To calculate and compare planning target volume (PTV) margins for an offline 3 mm tolerance, daily bony anatomy verification, tattoo alignment and online prostate marker matching with those currently used at our institution.

Seventy patients had offline bony anatomy megavoltage verification. 23 different patients underwent fiducial marker matching using daily online kilovoltage verification. Systematic and random errors were measured in the right–left (RL), superior–inferior (SI) and anterior–posterior (AP) directions. Geometric uncertainties from literature were used to help calculate the margins.

PTV margins (mm) were 7 RL, 12 SI and AP (3 mm tolerance offline bony), 6 RL, 11 SI and AP (daily online bony), 8 RL, 12 SI and AP (tattoo alignment) and 5 RL, 8 SI and 6 AP (online daily prostate marker correction).

Our current margins for conformal radiotherapy patients are too small for phase 2 in the SI and AP directions. Implementing online daily bony anatomy matching would not reduce the PTV margin significantly. Online daily marker correction showed current PTV71 Gy margins as excessive by (mm) 5 RL, 2 SI and 4 anterior.

This work aims to evaluate the effect of Hitachi 16-slice scanner reconstruction filters on Hounsfield unit (HU) variations. In the literature, there is a lack of information from a wide variety of scanners in this regard. In addition, not all studies have investigated the effect of reconstruction filters on HU in an exhaustive way.

The computerised imaging reference system electron density phantom (model 062M) was scanned with different substitute materials of different density from Hitachi 16-slice computed tomography. The raw images were obtained with four tube voltage settings: 80 kVp, 100 kVp, 120 kVp and 140 kVp. The raw images for each energy level were then reconstructed using different reconstruction filters.

The HU values of dense bone were significantly different when changing the reconstruction filters without beam hardening correction (BHC). Nevertheless, when selecting the BHC, this variation decreases heavily for 80 kVp and decreases slightly for 140 kVp, but it remains outside the tolerance of ±50 HU. However, for 100 kVp and 120 kVp, the differences in HU values become within the tolerances indicated for dense bone.

Changing image reconstruction filters during a dosimetric scan had a significant effect on HU in dense bone. Therefore, it is recommended to evaluate this effect during the commissioning phase. As a result, this study provides a methodology to comprehensively investigate the effect of reconstruction filters on HU.

During left-sided breast radiotherapy, the heart is often exposed to radiation dose. Shielding can be utilised to reduce heart exposure, but compromises the dose delivered to the breast tissue and, in a proportion of patients, to the tumour bed. Deep inspiration breath hold (DIBH) can be used as a technique to move the heart away from the treatment area and thus reduce heart dose. This study examines the efficacy of the Elekta Active Breathing Coordinator (ABC), a DIBH method, in reducing heart dose.

In total, 12 patients receiving radiotherapy to the left breast were planned for treatment with both a free-breathing (FB) and an ABC scan. The dose volume histogram data for the plans was analysed with respect to heart V13, V5 Gy, mean heart dose and ipsilateral lung V18 Gy. Tumour bed D98%, threshold lung volume in breath hold (BH) and the maximum BH time for each patient was also measured. Patients then received their radiotherapy treatment using the ABC plan and the systematic error in the craniocaudal, lateral and vertical axes was assessed using orthogonal imaging.

The median heart V13 Gy for FB and DIBH patients was 3% (range, 0·85–11·28) and 0% (range, 0–1·56), respectively, with a mean heart dose of 2·62 Gy (range, 1·21–4·93) in FB and 1·51 Gy (range, 1·17–2·22) in ABC. The median lung V18 Gy was 8·7% (3·08–14·87) in FB plans and 9% (4·88–12·82) in ABC plans. The mean systematic set-up errors in all three planes were within the departmental set-up tolerance of 5 mm for both techniques. Median FB tumour bed D98% was 97·4% (92·8–99·5) and 97·5% (97·3–98·5) for ABC.

ABC represents a good method of reducing radiation dose to the heart while not compromising on dose to the tumour bed, and it has a clear advantage over FB radiotherapy in reducing the risk of cardiac toxicity. It is tolerated well by patients and does not produce any difficulties in patient positioning.

While treating brain metastasis with whole-brain radiotherapy incorporating a simultaneous integrated boost (WBRT-SIB), the risk of hippocampus injury is high. The aim of this study is to compare dosimetrically between intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (VMAT) in sparing of hippocampus and organs at risk (OARs) and planning target volume (PTV) coverage.

In total, 16 patients presenting with more than one brain metastases were previously treated and then retrospectively planned using VMAT and IMRT techniques. For each patient, a dual-arc VMAT and another IMRT (five beams) plans were created. For both techniques, 30 Gy in 10 fractions was prescribed to the whole brain (WB) minus the hippocampi and 45 Gy in 10 fractions to the tumour with 0·5 cm margin. Dose–volume histogram (DVH), conformity index (CI) and homogeneity index (HI) of PTV, hippocampus mean and maximum dose and other OARs for both techniques were calculated and compared.

A statistically significant advantage was found in WB-PTV CI and HI with VMAT, compared to IMRT. There were lower hippocampus mean and maximum doses in VMAT than IMRT. The maximum hippocampus dose ranged between 15·5 and 19·2 Gy and between 18·4 and 20·6 Gy in VMAT and IMRT, respectively. The mean dose of the hippocampus ranged between 11·5 and 17·7 Gy and between 13·2 and 18·3 Gy in VMAT and IMRT, respectively.

Using WBRT-SIB technique, VMAT showed better PTV coverage with less mean and maximum doses to the hippocampus than IMRT. Clinical randomised studies are needed to confirm safety and clinical benefit of WBRT-SIB.

This article describes a collaborative project that aimed to develop a patient-centred curriculum in radiotherapy. In the wake of the Francis report in 2013 and a call for compassion to be a central tenet of health programmes, the project was a timely opportunity to enhance the radiotherapy curriculum.

Collaboration between university staff and patients and carers using the service improvement model Plan-Do-Study-Act was the method employed for the curriculum project. Two key discussion forums helped shape the curriculum plan, with module and course evaluation continuing to inform developments.

The key outcome of the project is that it has shaped the 'care' theme evident in the current undergraduate programme. Co-production methods resulted in the development of a range of shared classroom activities that focus on experiences, care values and communication strategies. The new curriculum has evaluated positively and the impact of learning is demonstrated both in the classroom and clinical setting. The project team have also influenced recruitment processes and patient and carer involvement in programme approval is embedded.

Working together, with patients and carers is an ideal method to enhance the curriculum and reflect the requirements in practice of current health and social care professions. Further developments in student assessment are planned.

To deliver radiation doses with higher accuracy, radiation treatment through megavoltage photon beams from linear accelerators, is accepted widely for treating malignancies. Before calibrating the linear accelerators, it is essential to make a complete analysis of all photon beam profile parameters. The main objective of this exploration was to investigate the 6 and 15 MV photon beam profile characteristics to improve the accuracy of radiation treatment plans.

In this exploration, treatment parameters like depth, field size and beam energy were varied to observe their effect on dosimetric characteristics of beam profiles in a water phantom, generated by linear accelerator Varian Clinac.

The results revealed that Dmax and Dmin decreased with increasing depth but increased with increasing field sizes. Both left and right penumbras increased with increasing depth, field size and energy. Homogeneity increased with field size but decreased with depth. Symmetry had no dependence on depth, energy and field size.

All the characteristics of photon beam dosimetry were analysed and the characteristics like homogeneity and symmetry measured by an ion chamber in a water phantom came within clinically acceptable level of 3 and 103%, respectively, thus fulfilled the requirements of standard linear accelerator specifications. This exploration can be extended to the determination of beam profile characteristics of electron and photon beams of other energies at various depths and field sizes for designing optimum treatment plans.