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The aim of this paper is to detail the experience obtained in implementing an image-guided radiation therapy program at the Northern Sydney Cancer Centre. This required retrofitting a Varian Clinac 21EX with an on-board imager. The commissioning and quality assurance procedures, organisation of a multidisciplinary image guided radiation therapy group, and the development of clinical protocols for orthogonal kV and cone beam computed tomography implementation are described. Reassessment of the image-guided radiation therapy program has continued as new equipment and software versions were made available in the department.

Background and Purpose: To determine whether radiation therapists (RTTs) and radiation oncologists (ROs) believe RTTs can lead patient treatment reviews., Materials and Methods: Phase 1 involved the construction of a checklist of the procedures followed during RO treatment reviews. Phase 2 employed the checklist to monitor the frequency of review procedures. From these data, questionnaires regarding RTTs' ability to carry out these procedures to be used in Phase 3 were developed. The questionnaires were distributed to RTTs and ROs at two large public cancer centres., Results: The majority of RTTs and ROs believed that RTTs could provide assurance and answer questions about side effects, treatment techniques, cancer, nutrition and logistics. ROs and RTTs agreed that RTTs were not capable of recommending medication or answering medical questions. Most RTTs thought they could decide if a patient should take a break from treatment if a standard protocol existed, but the ROs disagreed (P < 0.01). ROs believed that RTTs were capable of using the Common Toxicity Criteria system to grade side effects, but RTTs disagreed (P < 0.01). Concerns were raised about training, legalities, workloads, logistics, cost, patients' perspectives and remuneration., Conclusion: RTTs and ROs believed RTTs could lead treatment reviews with training, and support this role development.

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Aim: In patients with isocitrate dehydrogenase (IDH) mutated anaplastic glioma determine the dosimetric benefits of delivering radiation therapy using a PET guided integrated boost IMRT technique (ib-IMRT) compared with standard IMRT (s-IMRT) in reducing dose to normal brain.Methods: Ten patients with anaplastic glioma, identified as a favourable molecular subgroup through presence of IDH mutation, and managed with radiation therapy using an ib-IMRT were enrolled into a dosimetric study comparing two RT techniques: s-IMRT to 59.4Gy or ib-IMRT with 59.4/54Gy regions. Gross Tumour volume (GTV) and Clinical Target Volumes (CTV) were determined by MRI, 18F-Fluoroethyltyrosine (FET) and 18F-Fluorodeoxyglucose (FDG) PET imaging. A standard risk Planning Target Volume (PTVsr) receiving 59.4Gy (PTV59.4) in the s-IMRT technique was determined by MRI T2Flair and FET PET. For the ib-IMRT technique this PTVsr volume was treated to 54Gy, and the high-risk PTV (PTVhr) receiving 59.4Gy was determined as a higher risk region by FDG PET and MRI gadolinium enhancement. Standard dosimetric criteria and normal tissue constraints based on recent clinical trials were used in target delineation and planning. Normal Brain was defined as Brain minus CTV. Endpoints for dosimetric evaluation related to mean Brain dose (mBrainDose), brain volume receiving 40Gy (Brainv40) and 20Gy (Brainv20). The variation between the dosimetric endpoints for both techniques was examined using Wilcoxon analysis.Results: The 10 patients had tumours located in temporal (1), parietal (3), occipital (2) and bifrontal (4) regions. In ib-IMRT technique the median volume of PTVhr was 25.5 cm3 compared with PTVsr of 300.0 cm3. For dose to PTVhr the two treatments were equivalent (p = 0.33), and although the ibIMRT had a prescribed 10% dose reduction from 59.4Gy to 54Gy the median reduction was only 5.9%. The ib-IMRT dosimetry was significantly improved in normal brain endpoints specifically mBrainDose (p = 0.007), Brainv40 (p = 0.005) and Brainv20 (p = 0.001), with a median reduction of 9.3%, 19.0 and 10.8% respectively. After a median follow-up of 38 months two patients have progressed, with no isolated relapse in the dose reduction region.Conclusion: An approach using ib-IMRT for anaplastic glioma produces significant dosimetric advantages in relation to normal brain dose compared with s-IMRT plan. This is achieved without a significant reduction to the target volume dose despite the reduction in prescribed dose. This technique has advantages to minimise potential late neurocognitive effects from high dose radiation in patients with favorable subtype anaplastic glioma with predicted median survival beyond ten years. [ABSTRACT FROM AUTHOR]

The aim of this review is to explore the changing utility of radiotherapy in the treatment of patients with glioblastoma over the past 60 years. Together with surgery, radiotherapy has always been the cornerstone of treatment of glioblastoma, but techniques have significantly advanced over this time. The exploration of early two-dimensional techniques, investigation of dose escalation, concomitant chemotherapy and modern techniques, including intensity-modulated radiotherapy, image-guided radiotherapy, and volumetric-modulated arc therapy will be covered. In addition, current controversies including decreasing margin size, re-irradiation, treatment of elderly patients, and novel imaging tracers will be discussed. Future directions including immunotherapy and tumour treating fields are examined. Radiotherapy-based treatments cannot rely solely on advances in chemotherapy or immunotherapy to improve the overall survival of patients with glioblastoma. Radiation oncology needs to continue to develop and improve the delivery, target definition, and dose of radiotherapy to these patients to improve their survival and the toxicity associated with treatment. [ABSTRACT FROM AUTHOR]

The palliative radiotherapeutic management of unresectable non-small-cell lung cancer is controversial, with various fractionation (Fx) schedules available. We aimed to determine patient’s choice of Fx schedule after involvement in a decision-making process using a decision board. A decision board outlining the various advantages and disadvantages apparent in the Medical Research Council study of Fx schedules (17 Gy in two fractions vs 39 Gy in 13 fractions) was discussed with patients who met Medical Research Council eligibility criteria. Patients were then asked to indicate their preferred Fx schedules, reasons and their level of satisfaction with being involved in the decision-making process. Radiation oncologists (RO) could prescribe radiotherapy schedules irrespective of patients’ preferences. Of 92 patients enrolled, 55% chose the longer schedule. English-speaking patients were significantly more likely to choose the longer schedule ( P = 0.02, 95% confidence interval: 1.2–7.6). Longer Fx was chosen because of longer survival (90%) and better local control (12%). Shorter Fx was chosen for shorter overall treatment duration (80%), cost (61%) and better symptom control (20%). In all, 56% of patients choosing the shorter schedule had their treatment altered by the treating RO, whereas only 4% of patients choosing longer Fx had their treatment altered ( P < 0.001). Despite this, all (100%) patients were satisfied with being involved in the decision-making process. The decision board was useful in aiding decision-making, with both Fx schedules being acceptable to patients. Interestingly, despite the longer average survival associated with longer Fx, nearly half of the patients believed that this was not as important as a shorter duration of treatment and lower cost. Despite patients’ preferences, there were significant alterations of preferred schedules because of RO’s own biases. [ABSTRACT FROM AUTHOR]

The aims were to determine the median survival and prognostic factors of patients with central nervous system (CNS) metastases managed with whole-brain radiation therapy (WBRT), and to explore selection criteria in recently published clinical trials using aggressive interventions in CNS metastases. A retrospective audit was performed on patients managed with WBRT for CNS metastases. Potential prognostic factors were recorded and analysed for their association with survival duration. The proportion of patients with these factors was also compared with those of patients managed under three recently reported studies investigating aggressive interventions, such as radiosurgery and chemotherapy for CNS metastases. Seventy-three patients were treated with WBRT for cerebral metastases over a 12-month period. The median survival of the population was 3.4 months (95% confidence interval: 2.7–4.1), with 6- and 12-month survival rates of 30 and 18%, respectively. Significant prognostic factors for prolonged median survival were Eastern Cooperative Oncology Group status 0–2 ( P = 0.015), Medical Research Council neurological functional status 0–1 ( P = 0.006), and Recursive Partitioning Analysis Class 2 versus Class 3 ( P = 0.020). On multivariate analysis, younger patient age ( P = 0.02) and better performance status ( P < 0.01) were associated with improved outcome. When comparing these characteristics with selected published studies, our study cohort demonstrated a higher proportion of patients with poor performance status, a greater number of metastases per patient and a higher incidence of extracranial disease. This reflects the selected nature of patients in these published studies. Central nervous system metastases confer a poor prognosis and, for the majority of patients, aggressive interventions are unlikely to improve survival. The use of potentially toxic and expensive treatments should be reserved for those few in whom these studies have shown a potential benefit. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the relationship of posterior fossa radiation therapy duration (PFRTD) and relapse-free survival (RFS) following adjuvant craniospinal RT for childhood medulloblastoma. A retrospective audit was performed assessing all children aged <18 years managed with adjuvant craniospinal RT for medulloblastoma in Australia and New Zealand in 1980–1993. Children receiving prolonged (>180 days) pre-RT chemotherapy were excluded. Data were obtained for potential prognostic factors in domains of patient, tumour and treatment factors. Radiation therapy time factors assessed were PFRTD and time interval from surgery to commencement of RT (SRTD). The end-point assessed was RFS and analysis was performed using Cox regression and Kaplan–Meier survival. One hundred and eighty-nine children were identified from 10 oncology units, with data available from 182 children for analysis. Median follow up was 5.3 years. Seventy-three per cent of children presented with disease confined to the cerebellum; 13% had initial neuraxis disease. Macroscopic resection was described in 54%; 42% received adjuvant chemotherapy. Median RT dose and RT duration to PF was 55 Gy and 45 days, respectively. Seventy-eight relapses occurred with a 10-year actuarial RFS of 58.2% (standard error ± 4%). On univariate analysis, increasing PF dose ( P = 0.002), age >5 years ( P = 0.006), and more thorough extent of surgical resection ( P = 0.043) were associated with improved RFS; PFRTD ( P = 0.20) and SRTD ( P = 0.51) were not associated with RFS. On multivariate analysis, although both PF dose ( P = 0.004) and extent of surgery ( P = 0.045) remained strongly significant, RT duration was now associated with RFS ( P = 0.049). Other factors assessed that did not reach significance were patient age, local tumour extent, presence of internal shunt and use of chemotherapy. The importance of local treatment factors was confirmed in this audit with established prognostic factors such as primary tumour macroscopic resection and adequate PF RT dose being associated with RFS. A treatment time effect is weakly suggested, although less significant than RT dose delivered. [ABSTRACT FROM AUTHOR]

An outpatient radiotherapy department assessed how precautions implemented during the severe acute respiratory syndrome (SARS) outbreak affected patient satisfaction with doctor–patient interaction and explored variables potentially influencing satisfaction. The information obtained would help prepare us for future infectious disease outbreaks. Outpatients seen during the outbreak completed a validated questionnaire assessing satisfaction with doctor–patient interaction. Additional items assessed included patients’ perception of SARS measures and patient demographics. Of 149 patients, 97% had heard of SARS, 92% believed SARS precautions necessary, and 54% believed contracting SARS was possible despite the precautions. Patients were satisfied with doctors wearing masks (97%), temperature checks (97%), and patients wearing masks (96%). Despite the high satisfaction levels with SARS precautions, 24% believed it had adversely affected doctor–patient interaction. With regards to doctor–patient interaction, 94% of patients were satisfied. Patients were most satisfied with the ‘information exchange’ domain (mean score 3.23 out of 4) compared to other domains ( P < 0.0001, 100.00% confidence) and were less satisfied with the ‘empathy’ domain compared to other domains ( P < 0.0001, 100.00% confidence). Patients were most satisfied with understanding their treatment plan (100%), doctor being honest (97%) and being understood (96%). Patients were least satisfied with information about caring for their illness (61%), that the visit could be better (59%), and the doctor showing more interest (58%). On multivariate analysis, patients who were less satisfied with SARS measures were significantly less satisfied with doctor–patient interaction ( P = 0.0001). Dissatisfaction with SARS measures was associated with significant dissatisfaction for questions in all domains. Older age and non-breast cancer patients were also less satisfied with doctor–patient interaction. Most (94%) of patients were satisfied with doctor–patient interaction, despite implementation of infectious disease prevention measures. However, patients who were dissatisfied with the SARS precautions had poorer satisfaction. In particular, physician empathy appeared to be most adversely affected. The results have relevance to any radiotherapy department preparing contingency plans in the event of infectious disease outbreaks. [ABSTRACT FROM AUTHOR]

The New South Wales Breast Radiation Oncology Group has completed a prospective multicentre study of the impact of radiation therapy (RT) on acute toxicity and quality of life (QoL) in women with early breast cancer treated with breast conservation therapy. The patient group received adjuvant breast tangential RT after wide local excision of breast cancer. Acute toxicity and cosmesis was assessed quantitatively and qualitatively. European Organization of Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-30) and Perceived Adjustment to Chronic Illness Scale (PACIS) were the QoL instruments used. Of 175 women, 34.3% described lethargy leading to a significant disruption to normal activity during RT. At week 6, this had reduced to 7.5% reporting significant lethargy. No negative effects on QoL were noted over the time period of RT; EORTC demonstrated no difference (P = 0.79). PACIS recorded a significant improvement in functioning (P < 0.001) from baseline to week 6. Univariate analysis on potential predictive patient, tumour and treatment factors demonstrated an association of baseline pre-RT breast discomfort with worse lethargy (P = 0.03), EORTC (P < 0.01) and PACIS (P < 0.01) measures. This study confirms the minimal impact of RT on patient functioning at 6 weeks post-treatment. [ABSTRACT FROM AUTHOR]

Aims: To document the acute toxicity experienced by women receiving radiation therapy as part of breast-conservation therapy (BCT) for early breast cancer.Materials and methods: A retrospective review was undertaken of the medical records of 234 consecutive women managed with radiation therapy for BCT over a 2-year period. A policy of formal acute toxicity documentation was present during this period with descriptive measures as well as the Radiation Therapy Oncology Group (RTOG) acute toxicity scoring system. Cutaneous moist desquamation, peak RTOG score, breast oedema and chemotherapy dose intensity were end points assessed. Patient and treatment characteristics were investigated for their association with study end points using Chi-squared and logistic regression analyses.Results: A total of 223 (95%) of women had data available for analysis. All women were treated with tangential fields on megavoltage linear accelerators. Eighty-three (37.2%) women had systemic chemotherapy either delivered simultaneously in 58 and sequentially in 25. Moist desquamation occurred in 70 (31.4%) women; principally in the inframammary fold only in 43 (19.3%). Only 12 (5.4%) had a confluent moist reaction. Two hundred and ten (94%) women had a peak RTOG skin grade of 2 or less. Breast oedema was evident at treatment end in 46 (20.5%). On univariate analysis, physical factors, such as patient weight (P<0.001) and breast size (P<0.001), were significantly associated with moist desquamation, as were the volume of breast resected (P=0.02) and the use of chemotherapy (P=0.03). Only the physical factors remained significant on multivariate analysis. The presence of breast oedema was associated with surgical factors such as post-operative oedema (P<0.001) and infective complications (P<0.001). The use of concurrent chemoradiotherapy did not affect chemotherapy dose intensity, nor did the presence of moist desquamation increase the risk of febrile complications in chemotherapy-related neutropenia.Conclusion: This study confirms the relatively low incidence of significant acute toxicity experienced by women during radiation therapy as part of BCT. These study data should assist surgeons and women in the decision-making process forBCT. [Copyright &y& Elsevier]

Despite relatively favourable outcomes associated with IDH-mutant grade 3 gliomas, many patients present with diffuse non-enhancing disease involving multiple brain regions, prompting concern over both durable disease control and the morbidity associated with large volume radiation therapy. This study audits volumetric response, survival and functional outcomes in this 'large volume' subgroup that undergoes intensity modulated radiation therapy (IMRT). From a prospective database of 187 patients with IDH-mutant grade 3 gliomas managed with IMRT between 2008 and 2020, recorded PTV was divided into quartiles. The top quartile, termed the 'large volume cohort' (LVC), was identified. IMRT involved FET-FDG guided integrated boost (59.4/54Gy in 33 fractions). Manual volumetric segmentation of baseline, four months and 13 months post-IMRT tumour were performed for T1, T2 and T1gd MRI sequences. The primary endpoint was volumetric reduction on the T1 and T2 sequences at 13 months and analysed with relapse-free survival (RFS) and overall survival (OS). Morbidity endpoints were assessed at year four post-IMRT and included performance status (ECOG PS) and employment outcomes. The fourth quartile (LVC) identified 44 patients for whom volumetric analysis was available. The LVC had median PTV of 320cm3 compared to 186.2cm3 for the total group. Anaplastic astrocytoma and oligodendroglioma were equally distributed and tumour sites were frontal (54%), temporal (18%) and parietal lobes (16%). Median follow-up for survivors was 71.5 months. Projected 10-year RFS and OS in LVC was 40% and 62%, compared to 53% and 62% respectively in the overall cohort. The RFS (p = 0.06) and OS (p = 0.65) of the LVC was not significantly different to other PTV quartiles; however the impact of PTV volume reached significance when analysed as a continuous variable (RFS p < 0.01; OS p = 0.02). Median T1 volumes were 26.1cm3, 8.0cm3 and 5.3cm3 at months +0, +3 and +12, respectively. The corresponding T2 volumes were 120.8cm3, 29.1cm3 and 26.3cm3. The median T1 and T2 volume reductions were 77% (q1–3: 57–92%) and 78% (q1–3: 60–85%) at 13 months post-IMRT. Initial T2 volume was associated with worse RFS (p = 0.04) but not OS (p = 0.96). There was no association between median T2 volume reduction and RFS (p = 0.77). For patients assessable at year 4 post-IMRT, no late CTCAE Grade 3/4 toxicity events were recognised. 92% of patients were ECOG PS 0–1, 45% were employed at prior capacity and 28% were working with impairment. Patients with large volume IDH-mutant Grade 3 glioma demonstrated significant tumour reduction post-IMRT, and good long-term outcomes with respect to survival and functional status. Although larger IMRT volumes were associated with poorer RFS, this was also associated with the initial volume of non-enhancing tumour. • IDH-mutant Grade 3 glioma are brain tumours with good prognosis. • Standard management consists of surgery, radiotherapy and temozolamide. • Large tumours pose challenge of achieving local control with acceptable morbidity. • PET imaging and modern radiotherapy techniques allow conformal tumour delineation. • These techniques allow for good long-term control, survival and function. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Multicentre quality assurance of intensity-modulated radiotherapy planning: Beware the benchmarker" by M. Back, L. Oliver, R. Bromley, and T. Eade that was published in the previous issue.

Abstract: Aims: Volumetric-modulated arc therapy (VMAT) allows rapid delivery of radiotherapy. The aim of this planning study was to evaluate VMAT and dynamic intensity-modulated radiotherapy (IMRT) using a simultaneous integrated boost technique Patients and methods: Planning computed tomography data from 10 patients with locoregionally advanced oropharynx or nasopharynx carcinoma were selected. The prescription dose was 70, 63 and 56Gy to the high-dose, intermediate-dose and low-dose planning target volume (PTV), respectively, and planning parameters were according to Radiation Therapy Oncology Group IMRT protocols. VMAT and IMRT plans were calculated, and dose–volume histograms were created for plan evaluation and comparison. Results: Clinically acceptable plans were achieved for both IMRT and VMAT plans, although IMRT plans typically required three times the number of monitor units. The coverage of 95% of the PTV70 was between 96 and 100% of the prescribed dose for IMRT plans and 100% for all VMAT plans. There was a trend of improved dose conformity for IMRT plans. Both IMRT and VMAT achieved acceptable plans in terms of sparing of the spinal cord and brainstem. Contralateral parotid sparing was improved with VMAT, with a mean dose of 25.08Gy (range 21.35–30.02Gy) for oropharynx and 31.37Gy (range 23.47–35.52Gy) for nasopharynx cases. Conclusion: Simultaneous integrated boost VMAT achieved comparable plans to dynamic IMRT in complex head and neck cases and used two-thirds less monitor units. [Copyright &y& Elsevier]