Assessment of HDR brachytherapy-replicating prostate radiotherapy planning for tomotherapy, cyberknife and VMAT.

A dosimetric study was undertaken to assess the ability of Cyberknife (CK), Volumetric Modulated Arc Therapy (VMAT), and TomoTherapy (Tomo) to generate treatment plans that mimic the dosimetry of high dose-rate brachytherapy (HDR BT) for prostate cancer. The project aimed to assess the potential of using stereotactic body radiotherapy (SBRT) for boost treatment of high-risk prostate cancer patients where HDR BT in combination with conformal external beam radiotherapy (EBRT) is the standard of care. The datasets of 6 prostate patients previously treated with HDR BT were collated. VMAT, CK, and TomoTherapy treatment plans were generated for each dataset using the target and organ-at-risk structures as defined by the Radiation Oncologist during the HDR BT treatment process. The HDR BT plan isodoses were also converted into planning structures to assist the other modalities to achieve a HDR BT-like dose distribution. CK plans were created using both the iris collimator (IC) and a multileaf collimator (MLC). Comparison of the techniques was made based on dose-volume indices. Each plan was created at centres experienced using the respective treatment planning systems (TPS). Planning target volume (PTV V100%), i.e., the volume of the planning target volume (PTV) receiving 100% of the relative dose, in VMAT and TomoTherapy SBRT plans was higher than HDR BT plans. PTV V150% and V200%, i.e., volume of the PTV receiving 150% and 200% of the relative dose, were approached on all the CK MLC and TomoTherapy SBRT plans. However, it is not presently achievable for "virtual brachytherapy" SBRT to replicate the same high intraprostatic doses as HDR BT while meeting the constraints on the organs-at-risk (OARs). Half of the CK IC plans achieved PTV V150% but this was at the expense of high rectal dose. TomoTherapy and CK MLC plans achieved PTV V150% and V200% but the bladder dose was higher compared to CK IC plans. VMAT exhibited excellent PTV coverage based on V100 and OAR sparing, but without any ability to achieve the high intra-prostatic doses of HDR (V150% and V200%). SBRT techniques can be used to deliver hypofractionated radiotherapy to the PTV V100%. Based on the comparison of "physical" dose distributions, SBRT cannot presently achieve the same high intraprostatic doses as HDR BT while respecting the OAR constraints. SBRT still remains an attractive treatment option for delivering hypofractionated treatments for prostate cancer compared to HDR BT, in particular as it is less invasive and less resource intensive. Long-term outcomes of clinical trials comparing HDR BT and SBRT "prostate boosts" may show whether the high intraprostatic doses are clinically significant and correlate with outcomes.

Multi-observer contouring of male pelvic anatomy: Highly variable agreement across conventional and emerging structures of interest.

INTRODUCTION: This study quantified inter-observer contouring variations for multiple male pelvic structures, many of which are of emerging relevance for prostate cancer radiotherapy progression and toxicity response studies. METHODS: Five prostate cancer patient datasets (CT and T2-weighted MR) were distributed to 13 observers for contouring. CT structures contoured included the clinical target volume (CTV), seminal vesicles, rectum, colon, bowel bag, bladder and peri-rectal space (PRS). MR contours included CTV, trigone, membranous urethra, penile bulb, neurovascular bundle and multiple pelvic floor muscles. Contouring variations were assessed using the intraclass correlation coefficient (ICC), Dice similarity coefficient (DSC), and multiple additional metrics. RESULTS: Clinical target volume (CT and MR), bladder, rectum and PRS contours showed excellent inter-observer agreement (median ICC = 0.97; 0.99; 1.00; 0.95; 0.90, DSC = 0.83 ± 0.05; 0.88 ± 0.05; 0.93 ± 0.03; 0.81 ± 0.07; 0.80 ± 0.06, respectively). Seminal vesicle contours were more variable (ICC = 0.75, DSC = 0.73 ± 0.14), while colon and bowel bag contoured volumes were consistent (ICC = 0.97; 0.97), but displayed poor overlap (DSC = 0.58 ± 0.22; 0.67 ± 0.21). Smaller MR structures showed significant inter-observer variations, with poor overlap for trigone, membranous urethra, penile bulb, and left and right neurovascular bundles (DSC = 0.44 ± 0.22; 0.41 ± 0.21; 0.66 ± 0.21; 0.16 ± 0.17; 0.15 ± 0.15). Pelvic floor muscles recorded moderate to strong inter-observer agreement (ICC = 0.50-0.97), although large outlier variations were observed. CONCLUSIONS: Inter-observer contouring variation was significant for multiple pelvic structures contoured on MR.

International validation of the EORTC QLQ-PRT20 module for assessment of quality of life symptoms relating to radiation proctitis: a phase IV study.

BACKGROUND: Although patients experience radiation proctitis post radiotherapy no internationally tested instruments exist to measure these symptoms. This Phase IV study tested the scale structure, reliability and validity and cross-cultural applicability of the EORTC proctitis module (QLQ-PRT23) in patients who were receiving pelvic radiotherapy. METHODS: Patients (n = 358) from six countries completed the EORTC QLQ-C30, QLQ-PRT23 and EORTC Quality of Life Group debriefing questions. Clinicians completed the EORTC Radiation Therapy Oncology Group scale. Questionnaires were completed at four time-points. The module's scale structure was examined and validated using standard psychometric analysis techniques. RESULTS: Three items were dropped from the module (QLQ-PRT23 → QLQ-PRT20). Factor analysis identified five factors in the module: bowel control; bloating and gas; emotional function/lifestyle; pain; and leakage. Inter-item correlations were within r = 0.3-0.7. Test-Retest reliability was high. All multi-item scales discriminated between patients showing symptoms and those without symptomology. The module discriminated symptoms from the clinician completed scoring and for age, gender and comorbidities. CONCLUSION: The EORTC QLQ-PRT20 is designed to be used in addition to the EORTC QLQ-C30 to measure quality of life in patients who receive pelvic radiotherapy. The EORTC QLQ-PRT20 is quick to complete, acceptable to patients, has good content validity and high reliability. TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry (ANZCTR) ACTRN12609000972224 .

Publication rates of abstracts presented at the Royal Australian and New Zealand College of Radiologists annual scientific meetings: Any change since 2004?

INTRODUCTION: The aim of this study was to determine the publication rate of abstracts presented at annual Royal Australian and New Zealand College of Radiologists (RANZCR) conferences. METHODS: The College's Annual Scientific Meetings (ASMs) from 2010 to 2013 were examined, with the goal of comparing these results to the findings of an earlier identical study that examined RANZCR ASMs from 1996 to 1999. RESULTS: Of the 1152 research abstracts presented, 468 (41%) had been published as full articles. The overall abstract to publication ratio (APR) for radiology was 34% and for radiation oncology was 57%. For oral presentations, these were 44% for radiology and 55% for radiation oncology. Papers were published in a wide variety of journals but 23% of articles appeared in the College's journal, the Journal of Medical Imaging and Radiation Oncology. The mean time between presentation and publication was 16.5 months (median 17 months). CONCLUSION: Publication rates are comparable with international reports. The APR has increased since the previous study for both disciplines, but more so for Radiation Oncology.

What pelvic radiation disease symptoms are experienced by patients receiving external beam radiotherapy and a high-dose-rate brachytherapy boost for prostate cancer?

PURPOSE: Research describing proctitis or pelvic radiation disease symptoms of prostate cancer patients one year after external beam radiotherapy (EBRT) plus high-dose-rate (HDR) brachytherapy is limited. This study aimed to assess prostate cancer patients' pelvic radiation disease symptoms from baseline to 12 months post-radiotherapy. MATERIAL AND METHODS: Men with prostate cancer referred for EBRT and HDR brachytherapy were recruited. Patients' age, diagnosis, staging, PSA, past medical history, and treatment were recorded. Pelvic radiation disease symptoms were assessed via the Phase III EORTC proctitis module. Patients completed questionnaires before radiotherapy (baseline) and at one, three, six, and 12 months afterwards. To assess acute toxicity, symptoms one month after radiotherapy were compared with baseline. To assess post-treatment recovery, symptoms at three, six, and 12 months post radiotherapy were compared with one month. Symptom changes over time were assessed with linear mixed effect models. RESULTS: Two hundred and sixty-six patients were recruited. Mean scores were below 2 at all time-points. The proportion of patients experiencing symptoms were also calculated. Linear mixed effect models showed that time-point, age, and T-stage were associated with some pelvic radiation disease symptoms. CONCLUSIONS: Patients receiving EBRT plus HDR brachytherapy to the prostate experienced mild pelvic radiation disease symptoms. Determining the proportion of patients with symptoms provided the most meaningful data.

Participating in an International Stereotactic Radiotherapy Patient Registry: The Establishment of Data Collection Pathways.

Aim To describe data collection pathways and practical challenges experienced by an academic comprehensive cancer centre aiming to record clinical data for patients being treated with a novel radiotherapy treatment modality. Methods Various options to capture data from all patients treated with the CyberKnife Robotic Radiosurgery System at Sir Charles Gairdner Hospital (SCGH) in Western Australia were explored. An international multicenter web-based secure database established and maintained by the Radiosurgery Society the RSSearch® Patient Registry was selected. Data were collected and entered over four contiguous phases, with either opt-in or opt-out consent and the completion of Patient Reported Outcome questionnaires for specific sub-groups. Results Between April 2014 and June 2016, 461 patients at Sir Charles Gairdner Hospital were enrolled in the RSSearch® Patient Registry with the collection of over 17,500 data items. From 461 patients enrolled, 447 patients were treated with the CyberKnife Robotic Radiosurgery System. The majority of patients were treated for either a malignant primary (43.2%) or metastatic disease (39.4%). The establishment of matrix organisational processes for data collection led to the development of improved workflow patterns and data collection pathways. Conclusions This article describes the processes developed by a single centre to establish an efficient system for data collection and participation in an international registry. The opt-out approach was more efficient in terms of patient recruitment compared to the informed-consent method used in earlier phases. The experience of this single centre may help inform other institutions considering data collection options for assessments of new or novel treatments.

First Australian experience of treating localised prostate cancer patients with CyberKnife stereotactic radiotherapy: early PSA response, acute toxicity and quality of life.

INTRODUCTION: This study is to evaluate biochemical response, acute toxicity and health-related quality-of-life (QOL) outcomes among prostate cancer patients following stereotactic body radiation therapy (SBRT) in the first Australian CyberKnife facility. METHODS: Forty-five consecutive patients with clinically localised prostate cancer were treated with SBRT using CyberKnife technology and enrolled in this study. Protocol treatment consisted of 36.25 Gy in five fractions. PSA and acute toxicity was assessed at each follow-up visit and QOL was assessed using the European Organisation for Research and Treatment of Cancer (EORTC) Global Health Status (GHS) C30 and PR25 questionnaires and the Karnofsky Performance Status (KPS). Distance of travel for treatment was recorded. RESULTS: The median prostate-specific antigen (PSA) level declined from the initial value of 6.9 ng/mL to 1.5 ng/mL at 6 months and 0.6 ng/mL at 18 months post-treatment. Results were similar in patients who did not receive hormone therapy. Acute grade 1 gastrointestinal (GI) and genitourinary (GU) toxicities were found in 11.1% and 24.4% of patients respectively. Acute grade 2 GI and GU toxicities were found in 2.2% and 11.1% of patients respectively. There were no grade 3 and grade 4 toxicities. Mean urinary symptom score was 14.8 at baseline, 17.2 at 6 weeks and 18.3 at 6 months (P > 0.05). Mean bowel symptom score was 2.7 at baseline, 4.2 at 6 weeks and 6.3 at 6 months (P > 0.05). The mean GHS score improved from 81.3 at baseline to 82.4 at 6 weeks, and was 75.6 at 6 months (P > 0.05, not significant). Compared to baseline KPS, there was a significant mean decrease from baseline of 96.7 to 93.3 at the 6-week follow-up (P = 0.0043), which then recovered to 94.3 at the 6-month follow-up (P = 0.1387). CONCLUSIONS: Early results show promising PSA response. Acute toxicity seemed comparable to results from conventionally fractionated radiotherapy and to international prostate SBRT studies. EORTC PR25 and C30 scores did not reveal any significant change from baseline, and although there was a decrease in KPS, the absolute decrease was small.

A randomised comparison of three different immobilisation devices for thoracic and abdominal cancers.

INTRODUCTION: Patient immobilisation is critically important for both highly conformal conventionally fractionated radiotherapy and for stereotactic body radiotherapy. Different immobilisation devices are available to maintain patient position for radiotherapy but the most suitable one remains unknown. METHODS: Forty-five patients were randomly allocated to one of three immobilisation devices; the Q fix arm shuttle, BodyFIX without wrap or BodyFIX with wrap. Patients were imaged before and after treatment to ascertain intra-fraction and inter-fraction motion. Bony anatomy was used for matching to determine the positional accuracy of each device. Treatments were timed using a standard method. Patient comfort and staff satisfaction questionnaires were also issued to determine comfort, ease of use and preferences for each device. RESULTS: The BodyFIX without wrap was the more accurate device; however, the differences between the devices were not statistically significant. The BodyFIX with wrap was found to take significantly longer to set up and set down compared to the arm shuttle and the BodyFIX without wrap (all P < 0.001). Patients (37%) marginally preferred the BodyFIX with wrap. Most (81%) staff preferred the BodyFIX without wrap. CONCLUSION: Immobilisation using the BodyFIX without wrap was deemed to be suitable for clinical use. It was a clinically accurate device, the more efficient in terms of set up and set down time, the most preferred by staff and was accepted by patients.

Peer review of cancer multidisciplinary teams: is it acceptable in Australia?

OBJECTIVE: To develop a peer-review model for assessment and quality improvement of cancer multidisciplinary teams (MDTs) and qualitatively assess its feasibility and acceptability in Australia. DESIGN, SETTING AND PARTICIPANTS: A peer-review methodology was developed, based on the United Kingdom's National Health Service peer-review model and a comprehensive literature review. This was pilot tested in three mature MDTs in different settings. Semi-structured interviews were conducted between December 2012 and July 2013 with all five peer reviewers and 17 MDT members. Thematic analysis was undertaken using a framework approach. RESULTS: Peer reviewers and MDT members found the process reasonable, constructive and useful; however, those involved in the preparation for the review found it time-consuming. Most MDT members considered the final report accurate and reflective of their service. Recommendations in the report were met with mixed reactions: several MDT members perceived some recommendations to be particularly relevant, while others viewed the same recommendations as impractical or of limited value. Many participants were unsure if recommendations would be fully implemented. The majority saw value in the process and expressed support for its implementation locally and nationally; however, feedback suggests the most appropriate format is yet to be established. CONCLUSIONS: Peer review of cancer MDTs is feasible and acceptable. We describe valuable lessons learnt and recognise that further development of the proposed peer-review model and national benchmarking of MDTs against established outcome measures is required if this process is to be widely implemented.

Stereotactic Body Radiotherapy for Clinically Localized Prostate Cancer: Toxicity and Biochemical Disease-Free Outcomes from a Multi-Institutional Patient Registry.

OBJECTIVES: To report on initial patient characteristics, treatment practices, toxicity, and early biochemical disease-free survival (bDFS) of localized prostate cancer treated with stereotactic body radiotherapy (SBRT) and enrolled in the RSSearch(®) Patient Registry. METHODS:  A retrospective analysis was conducted on patients with clinically localized prostate cancer enrolled in RSSearch(®) from June 2006 - January 2015. Patients were classified as low-risk (PSA ≤ 10 ng/ml, T1c-T2a, Gleason score ≤ 6), intermediate-risk (PSA 10.1 - 20 ng/ml, T2b-T2c, or Gleason 7), or high-risk (PSA > 20 ng/ml, T3 or Gleason ≥ 8). Toxicity was reported using Common Toxicity Criteria for Adverse Events, version 3. Biochemical failure was assessed using the Phoenix definition (nadir + 2 ng/ml). The Kaplan-Meier analysis was used to calculate bDFS and association of patient and tumor characteristics with the use of SBRT. RESULTS:  Four hundred thirty-seven patients (189 low, 215 intermediate, and 33 high-risk) at a median of 69 years (range: 48-88) received SBRT at 17 centers. Seventy-eight percent of patients received 36.25 Gy/5 fractions, 13% received 37 Gy/5 fractions, 6% received 35 Gy/5 fractions, 3% received 38 Gy/4 fractions, and 5% received a boost dose of 19.5-29 Gy following external beam radiation therapy. Median follow-up was 20 months (range: 1-64 months). Genitourinary (GU) and gastrointestinal (GI) toxicities were minimal, with no acute or late Grade 3+ GU or GI toxicity. Late Grade 1 and 2 urinary frequency was 25% and 8%. Late Grade 1 and 2 proctitis was 3% and 2%. Median PSA decreased from 5.8 ng/ml (range: 0.3-43) to 0.88, 0.4, and 0.3 ng/ml at one, two, and three years. Two-year bDFS for all patients was 96.1%. Two-year bDFS was 99.0%, 94.5%, and 89.8% for low, intermediate, and high-risk patients (p < 0.0001). Two-year bDFS was 99.2%, 93.2%, and 90.4% for Gleason ≤ 6, Gleason 7, and Gleason ≥ 8 (p < 0.0001). Two-year bDFS was 96.4%, 97.2%, and 62.5% for PSA ≤ 10 ng/ml, PSA 10.1 - 20 ng/ml, and PSA > 20 ng/ml (p < 0.0001). Clinical T Stage was not significantly associated with bDFS.  CONCLUSIONS:  Early disease outcomes of SBRT for the treatment of clinically localized prostate cancer from a multicenter patient registry compare favorably with reports from single institutions. Acute and late GU and GI toxicities were minimal, and PSA response to SBRT was highly encouraging. Continued accrual and follow-up will be necessary to confirm long-term results.

Technical quality assurance during the TROG 03.04 RADAR prostate radiotherapy trial: are the results reflected in observed toxicity rates?

INTRODUCTION: Multicentre radiotherapy clinical trials can incorporate quality assurance (QA) procedures for ensuring consistent application of the trial protocol in the planning, delivery and reporting of participant treatments. Subsequently detected variations from trial protocol have previously been shown to reduce treatment efficacy, although little has been shown for toxicity rates. The purpose of this study was to investigate the association of QA measures and protocol variations on toxicity incidence in the context of a prostate radiotherapy trial. METHODS: Using QA records from the TROG 03.04 RADAR trial, the impact of variations on gastrointestinal (GI) and genito-urinary (GU) toxicities was investigated. RESULTS: Protocol variation rates were lower than reported in previous studies, and showed little correlation with GI toxicity outcomes. Variations classified as 'major' showed a non-significant trend for increased toxicity relative to those classified as 'minor'. Results from a Level III phantom-based dosimetry study showed some correlation with GI toxicity, whereas ranking on a set-up accuracy study did not impact on toxicity. Toxicity in general increased with the number of participants accrued per centre, at odds with previous reports relating to disease progression, with a potential link to increases in low-mid-range rectal doses in the cohort from higher-accruing centres. No QA-related variables correlated with GU toxicities. CONCLUSIONS: Besides non-significant trends, minimal association was observed between QA variables and toxicity rates for the RADAR trial. The intention of the trial's QA programme was to reduce treatment variations and minimise toxicity in the context of a relevantly advanced treatment approach.

Evaluating the effects of aluminum-containing and non-aluminum containing deodorants on axillary skin toxicity during radiation therapy for breast cancer: a 3-armed randomized controlled trial.

PURPOSE: Deodorant use during radiation therapy for breast cancer has been controversial as there are concerns deodorant use may exacerbate axillary skin toxicity. The present study prospectively determined the use of both aluminum-containing and non aluminum containing deodorants on axillary skin toxicity during conventionally fractionated postoperative radiation therapy for breast cancer. METHODS AND MATERIALS: This 3-arm randomized controlled study was conducted at a single center, tertiary cancer hospital between March 2011 and April 2013. Participants were randomized to 1 of 2 experimental groups (aluminum-containing deodorant and soap or non-aluminum containing deodorant and soap) or a control group (soap). A total of 333 participants were randomized. Generalized estimating equations were used to estimate and compare the odds of experiencing high levels of sweating and skin toxicity in each of the deodorant groups to the odds in the control group. The study evaluated a range of endpoints including objective measurements of axilla sweating, skin toxicity, pain, itch and burning. Quality of life was assessed with a validated questionnaire. RESULTS: Radiation characteristics were similar across all groups. Patients in the deodorant groups did not report significantly different ratings for axillary pain, itch, or burning compared with the control group. Patients in the aluminum-containing deodorant group experienced significantly less sweating than the control; the odds of their sweating being barely tolerable and frequently or always interfering with their daily activities was decreased by 85% (odds ratio, 0.15; 95% confidence interval, 0.03-0.91). CONCLUSIONS: We found no evidence that the use of either aluminum-containing or non-aluminum containing deodorant adversely effects axillary skin reaction during conventionally fractionated radiation therapy for breast cancer. Our analysis also suggests patients in the aluminum-containing deodorant arm had significantly less sweating without increased symptoms of axillary radiation skin toxicity. These results add to the evidence that the prescription of deodorants during radiation therapy for breast cancer is now questionable.

Catheter tract metastasis associated with indwelling pleural catheters.

BACKGROUND: Indwelling pleural catheters (IPCs) are commonly used to manage malignant effusions. Tumor spread along the catheter tract remains a clinical concern for which limited data exist. We report the largest series of IPC-related catheter tract metastases (CTMs) to date, to our knowledge. METHODS: This is a single-center, retrospective review of IPCs inserted over a 44-month period. CTM was defined as a new, solid chest wall lesion over the IPC insertion site and/or the tunneled subcutaneous tract that was clinically compatible with a malignant tract metastasis. RESULTS: One hundred ten IPCs were placed in 107 patients (76.6% men; 60% with mesothelioma). CTM developed in 11 cases (10%): nine with malignant pleural mesothelioma and two with metastatic adenocarcinoma. CTM often developed late (median, 280 days; range, 56-693) post-IPC insertion. Seven cases had chest wall pain, and six received palliative radiotherapy to the CTM. Radiotherapy was well tolerated, with no major complications and causing no damage to the catheters. Longer interval after IPC insertion was the sole significant risk factor for development of CTM (OR, 2.495; 95% CI, 1.247-4.993; P = .0098) in the multivariate analyses. CONCLUSIONS: IPC-related CTM is uncommon but can complicate both mesothelioma and metastatic carcinomas. The duration of interval after IPC insertion is the key risk factor identified for development of CTM. Symptoms are generally mild and respond well to radiotherapy, which can be administered safely without removal of the catheter.

Survey of high-dose-rate prostate brachytherapy practice in Australia and New Zealand, 2010-2011.

INTRODUCTION: A survey was designed to establish a baseline data set for the current routine practice of high-dose-rate prostate brachytherapy (HDR-PB) in Australia and New Zealand. Existing treatment protocols and clinical implementations are not generally known. METHODS: The survey, for the 2010 and 2011 calendar years, collected data including number of patients treated; equipment used; imaging modalities; applicator verification and correction methods; dose prescriptions and normal tissue dose constraints. The number of HDR-PB patients treated was compared with the most recently published prostate cancer incidence data in Australia and in New Zealand. Total biologically equivalent doses in 2.0 Gy fractions (EQD2) were calculated for each prescription regime reported. RESULTS: There were reductions, of 25-60%, in patients treated with HDR-PB from 2010 to 2011 in four departments. Prostate cancer patients are two to six times more likely to be prescribed HDR-PB in Western Australia than elsewhere in the region. There were 12 different treatment prescriptions, with EQD2 doses ranging from 73.5 to 97.6 Gy, among the 18 reported by survey respondents. Normal tissue definition methodology and dose constraints varied, and 13 of 15 departments reported that no particular published external guidelines were followed in full. CONCLUSION: The high survey response rate, 15 of 17 departments, has provided a representative baseline data set of contemporary HDR-PB practice in Australia and New Zealand that may assist government and professional bodies, such as the Australasian Brachytherapy Group, in formulating recommendations, setting standards and future planning.

Radiotherapy of abdomen with precise renal assessment with SPECT/CT imaging (RAPRASI): design and methodology of a prospective trial to improve the understanding of kidney radiation dose response.

BACKGROUND: The kidneys are a principal dose-limiting organ in radiotherapy for upper abdominal cancers. The current understanding of kidney radiation dose response is rudimentary. More precise dose-volume response models that allow direct correlation of delivered radiation dose with spatio-temporal changes in kidney function may improve radiotherapy treatment planning for upper-abdominal tumours. METHODS/DESIGN: The Radiotherapy of Abdomen with Precise Renal Assessment with SPECT/CT Imaging (RAPRASI) is an observational clinical research study with participating sites at Sir Charles Gairdner Hospital (SCGH) in Perth, Australia and the Peter MacCallum Cancer Centre (PMCC) in Melbourne, Australia. Eligible patients are those with upper gastrointestinal cancer, without metastatic disease, undergoing conformal radiotherapy that will involve incidental radiation to one or both kidneys. For each patient, total kidney function is being assessed before commencement of radiotherapy treatment and then at 4, 12, 26, 52 and 78 weeks after the first radiotherapy fraction, using two procedures: a Glomerular Filtration Rate (GFR) measurement using the 51Cr-ethylenediamine tetra-acetic acid (EDTA) clearance; and a regional kidney perfusion measurement assessing renal uptake of 99mTc-dimercaptosuccinic acid (DMSA), imaged with a Single Photon Emission Computed Tomography / Computed Tomography (SPECT/CT) system. The CT component of the SPECT/CT provides the anatomical reference of the kidney's position. The data is intended to reveal changes in regional kidney function over the study period after the radiotherapy. These SPECT/CT scans, co-registered with the radiotherapy treatment plan, will provide spatial correlation between the radiation dose and regional renal function as assessed by SPECT/CT. From this correlation, renal response patterns will likely be identified with the purpose of developing a predictive model. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry: ACTRN12609000322235.

Validation of a radiobiological model for low-dose-rate prostate boost focal therapy treatment planning.

PURPOSE: Low-dose-rate brachytherapy using iodine-125 seeds is a highly efficacious treatment for low-risk prostate cancer. We propose a bioeffect model may be used to target an ablative dose to the tumor with a lower, therapeutic dose to low-risk regions to maintain high rates of tumor control with reduced toxicity. We report on the validation of the model and derivation of the optimal cutpoint value of tumor control probability (TCP) that predicts for freedom from biochemical failure. METHODS AND MATERIALS: The TCP was calculated from postimplant dosimetry data for 423 prostate cancer patients from three Australian institutions. To apply the model, the prostate was mathematically divided into 12 subsections with tumor characteristics, including a nonuniform distribution of tumor cell density, derived from the literature. RESULTS: When TCP values were above and below 0.62, the 5-year freedom from biochemical failure were 93.7% (95% confidence interval [CI], 90.4, 96.4%) and 88.8% (95% confidence interval, 81.3, 94.5%), respectively (p = 0.004). CONCLUSIONS: Using postimplant dosimetry data, the TCP model was able to predict for freedom from biochemical failure. The cutpoint value that would be used clinically depends on the selection of the model parameters, but the potential for the model to be used in the optimization of treatment planning is demonstrated.

An international survey on liver metastases radiotherapy.

BACKGROUND: An international survey of radiation therapy (RT) of liver metastases was undertaken by the Liver Cancer Workgroup of the Third International Consensus on Metastases Workshop at the 2010 American Society for Radiation Oncology (ASTRO) meeting. MATERIAL AND METHODS: Canadian, European, Australian, New Zealand and American centers participated in this online survey. The survey had four objectives: 1) to describe the practice patterns for RT of liver metastases; 2) to report on the use of low-dose RT for symptomatic liver metastases; 3) to report on the use of technology; and 4) to describe the regional differences in the management of liver metastases. RESULTS: A total of 69 individuals treating liver metastases with radiotherapy responded to the survey. Regional response rates ranged from 39% to 50%. The primary professional affiliation of all respondents was evenly distributed amongst ASTRO, CARO, ESTRO and TROG/RANZCR. A 36% increase in the average annual number of referrals over the past five years is reported. The majority of referrals were for radical RT. The most common technologies used were 4D-CT (61%), SBRT (55%), IGRT (50%), and/or IMRT (28%). A uniform treatment approach was not found. The most commonly employed radical regimens were 45 Gy in 3 fractions, 40-50 Gy in 5 fractions, and 45 Gy in 15 fractions. Palliative regimens included 20 Gy in 5 fractions, 30 Gy in 10 fractions, 8 Gy in 1 fraction, and 10 Gy in 2 fractions. CONCLUSIONS: This survey suggests radiation oncologists will be seeing more referrals for liver RT. The majority of experience in liver metastases RT is with radical SBRT for focal metastases rather than low-dose palliative RT for symptom control. There is significant variation in technology utilization and dose regimens. Prospective studies or registries may allow for comparison of regimens and identification of parameters to optimize patient selection.

Radiotherapy in the management of high-grade gliomas diagnosed in Western Australia: a patterns of care study.

PURPOSE: Radiotherapy (RT) plays an integral role in the management of high-grade glioma (HGG). However, there is little information on the patterns of care in unselected Australian patients with HGG. PATIENT AND METHODS: This prospective cohort study collected information on patients with a diagnosis of HGG managed in Western Australia over a 25-month period from 2006 to 2008. RT treatment and survival data were analysed. RESULTS: 86% of Western Australian patients with HGG were treated at the study site over this period. Of these, 80% were reviewed by a radiation oncologist with RT recommended in 88% of cases. One hundred eighty-seven patients proceeded to have RT, with most receiving 60 Gy in 30 fractions with limited field external beam radiotherapy (LFRT). Median survival from diagnosis was 13.6 months for all patients and 15.4 months for those planned for treatment with 60 Gy in 30 fractions. The median time from surgery to the start of RT was 41 days. Longer waiting times were not predictors of poor survival. Failure to receive all planned treatment (13% of patients) predicted for poor survival (hazard ratio 0.38). CONCLUSION: Dose and fractionation practices show concordance with published data and guidelines. Survival is also consistent with clinical trial data for patients planned for aggressive therapy. Nevertheless, a substantial number of patients are not suited to aggressive therapy or fail to complete planned therapy, and these patients have poor outcomes. Treatment delays did not affect survival outcomes but are confounded by earlier treatment of those unsuited to LFRT.

Radiotherapy for liver metastases: a review of evidence.

Over the past decade, there has been an increasing use of radiotherapy (RT) for the treatment of liver metastases. Most often, ablative doses are delivered to focal liver metastases with the goal of local control and ultimately improving survival. In contrast, low-dose whole-liver RT may be used for the palliation of symptomatic diffuse metastases. This review examines the available clinical data for both approaches. The review found that RT is effective both for local ablation of focal liver metastases and for palliation of patients with symptomatic liver metastases. However, there is a lack of a high level of evidence from randomized clinical trials.

The use of On-Board Imaging to plan and deliver palliative radiotherapy in a single cohesive patient appointment.

To develop and assess a method of palliative radiotherapy utilising a kilovoltage imaging system incorporated with a linear accelerator. The conventionally separate procedures of simulation, planning and treatment were merged into a single appointment on a linear accelerator. The process was tested using a humanoid phantom and hypothetical treatment scenarios. A clinical investigation was then undertaken for patients requiring palliative radiotherapy. A total of 10 treatment sites were simulated, planned and treated using the online approach. Each step was timed for both the phantom and patient treatments and was compared with a simulation process involving a separate appointment on a conventional simulator. The contrast and resolution achievable with the linear accelerator-based imaging system was found to be comparable with a conventional simulator. Bony anatomy was plainly visible and suitable for target definition. The mean total treatment time for the humanoid phantom (n = 5) was 21.4 ± 0.9 (standard error) mins. The mean total treatment time for actual patients (n = 10) was 25.7 ± 1.6 mins (the mean simulation, planning and treatment times were 11.0 ± 0.5 mins, 14.5 ± 1.0 mins and 3.6 ± 0.2 mins, respectively). This study demonstrated that palliative radiotherapy treatments can be simulated, planned and treated in a single cohesive patient appointment, using an online approach that is technically comparable with the conventional simulation method. This approach has the potential to expedite palliative radiotherapy service delivery and reduce resource burdens by minimising the number of patient appointments and wait times between appointments.