Dynamic Contrast-enhanced Magnetic Resonance Imaging Evaluation of Whole Tumour Perfusion Heterogeneity Predicts Distant Disease-free Survival in Locally Advanced Rectal Cancer.

AIMS: To evaluate diffusion-weighted imaging and dynamic contrast-enhanced magnetic resonance imaging for the prediction of disease-free survival (DFS) in patients with locally advanced rectal cancer. MATERIALS AND METHODS: Patients with stage II or III rectal adenocarcinoma undergoing neoadjuvant chemoradiotherapy (CRT) and surgery were eligible. Patients underwent multi-parametric magnetic resonance imaging (diffusion-weighted imaging and dynamic contrast-enhanced) before CRT, during CRT (week 3) and after CRT (1 week prior to surgery). Whole tumour apparent diffusion coefficient (ADC) and Ktrans histogram quantiles (10th, 25th, 50th, 75th, 90th) were extracted for analysis. The associations between ADC and Ktrans at three timepoints with time to relapse were analysed as a continuous variable using a Cox proportional hazard model. RESULTS: Thirty-three patients were included in this analysis. The median follow-up was 4.4 years. No patient had locoregional relapse. Nine patients developed distant metastases. The hazard ratios for after CRT Ktrans 10th (P = 0.035), 25th (P = 0.048), 50th (P = 0.046) and 75th (P = 0.045) quantiles were statistically significant for DFS. The best Ktrans cut-off point after CRT for predicting relapse was 28 × 10-3 mL/g/min (10th quantile), with a higher Ktrans value predicting distant relapse. The 4-year DFS probability was 0.93 for patients with after CRT Ktrans value ≤28 × 10-3 mL/g/min versus 0.45 for patients with after CRT Ktrans value >28 × 10-3 mL/g/min. ADC was not able to predict DFS. CONCLUSIONS: Patients with higher Ktrans values after CRT (before surgery) in a histogram analysis of whole tumour heterogeneity had a significantly lower 4-year distant DFS and could be considered for more intense systemic therapy.

Actual Versus Optimal Radiotherapy Utilisation for Metastatic Cancer Patients in the 45 and Up Study Cohort, New South Wales.

AIMS: Radiotherapy can provide quality of life and/or survival benefits to patients with metastatic cancer on diagnosis (MCOD). However, little is known about radiotherapy utilisation in this population. We compared the optimal radiotherapy rates with actual uptake for people who present with MCOD in the 45 and Up Study cohort, and examined factors associated with utilisation. MATERIALS AND METHODS: In total, 267 153 individuals aged ≥45 enrolled in the Sax Institute's 45 and Up Study completed a baseline questionnaire during 2006-2009, providing sociodemographic and health information and consent for linkage to administrative health databases. Participants diagnosed up to December 2013 with MCOD were identified in the New South Wales Cancer Registry. Radiotherapy receipt was determined from claims to the Medicare Benefits Schedule and/or records in the New South Wales Admitted Patient Data Collection (2006 to June 2016). The Collaboration for Cancer Outcomes, Research and Evaluation optimal utilisation model was adapted for patients with MCOD to provide a benchmark. RESULTS: Of 17 687 participants diagnosed with cancer after completion of the baseline questionnaire, 2392 had MCOD. Of patients with MCOD, 25% had primary lung cancer, which was the most common site. The actual radiotherapy utilisation rate for all patients was 32.3%, lower than the optimal of 45.0%. From multivariable analysis, patients who were aged ≥80 years and/or needed help with daily tasks and/or had a Charlson Comorbidity Index ≥2 were less likely to receive radiotherapy. CONCLUSIONS: Actual uptake of radiotherapy was below optimal. Elderly patients and/or those with more comorbidities were less likely to receive radiotherapy. These results suggest a potential role for advocacy and education around radiotherapy for these patient groups.

Patterns of palliative radiotherapy fractionation for brain metastases patients in New South Wales, Australia.

BACKGROUND AND PURPOSE: There is a paucity of studies examining variation in the use of palliative radiation therapy (RT) fractionation for brain metastases. The aim of this study is to assess variation in palliative RT fractionation given for brain metastases in New South Wales (NSW), Australia, and identify factors associated with variation. MATERIALS AND METHODS: This is a population-based cohort of patients who received whole brain RT (WBRT) for brain metastases (2009-2014), as captured in the NSW Central Cancer Registry. A logistic regression model was used to identify factors associated with fractionation type. RESULTS: Of the 2,698 patients that received WBRT, 1,389 courses (51%) were < 6 fractions, 1,050 courses (39%) were 6-10 fractions, and 259 courses (10%) were > 10 fractions. Older patients were more likely to be treated with shorter courses (P < 0.0001). Patients with primary lung cancers were more likely to receive shorter courses compared with other primary cancers (P < 0.0001). Patients without surgical excision were more likely to receive < 6 fractions compared to those who underwent surgical excision. Shorter courses were more likely to be delivered to patients with the most disadvantaged socioeconomic status (SES) compared with patients with the least disadvantaged SES (P < 0.0001). There were significant fluctuations in the proportion of courses using lower number of fractions over time from 2009 to 2014, but no apparent trend (P = 0.02). There was wide variation in the proportion of shorter courses across residence local health districts, ranging from 24% to 69% for < 6 fractions, 21% to 72% for 6-10 fractions, and 4% to 20% for > 10 fractions (P < 0.0001). CONCLUSION: This study has identified significant unwarranted variations in fractionation for WBRT in NSW. Accelerating the uptake of shorter fractionation regimens, if warranted through evidence, should be prioritised to enhance evidence-based care.

Patterns of use of palliative radiotherapy fractionation for bone metastases and 30-day mortality.

BACKGROUND AND PURPOSE: Adoption of single-fraction radiation therapy (SFRT) has not been universal in the palliative treatment of bone metastases, despite evidence supporting its safety and efficacy. The aim of this study was to assess SFRT use for bone metastases in New South Wales (NSW), Australia, and the rate of 30-day mortality (30DM). MATERIALS AND METHODS: This is a population-based cohort of patients who received palliative radiation therapy (RT) for bone metastases (2009-2014), as captured in the NSW Central Cancer Registry. A logistic regression model was used to identify factors associated with fractionation type. The proportion of patients dying within 30-days from treatment start date was calculated. RESULTS: Of the 14,602 courses of palliative RT delivered for bone metastases, 30% were SFRT. SFRT was more likely to be delivered to older patients: ≥80 years (34%) versus < 60 years (28%). Patients with lower socioeconomic status (SES) (35%) were more likely to receive SFRT compared with higher SES (25%). SFRT delivered to patients from outer regional area of residence (34%) were higher compared to those from the major city (29%). The proportion of SFRT delivered to patients with comorbidities ≥2 (34%) was higher than patients with no comorbidity (29%). SFRT was associated with higher 30DM of 21% compared with 11% for multi-fraction RT (MFRT). CONCLUSION: SFRT is underused for the treatment of bone metastases in NSW. This is an impetus to develop tools making SFRT obligatory in this setting unless there is good justification not to.

The population benefit of evidence-based radiotherapy: 5-Year local control and overall survival benefits.

BACKGROUND: To describe the population benefit of radiotherapy in a high-income setting if evidence-based guidelines were routinely followed. METHODS: Australian decision tree models were utilized. Radiotherapy alone (RT) benefit was defined as the absolute proportional benefit of radiotherapy compared with no treatment for radical indications, and of radiotherapy over surgery alone for adjuvant indications. Chemoradiotherapy (CRT) benefit was the absolute incremental benefit of concurrent chemoradiotherapy over RT. Five-year local control (LC) and overall survival (OS) benefits were measured. Citation databases were systematically queried for benefit data. Meta-analysis and sensitivity analysis were performed. FINDINGS: 48% of all cancer patients have indications for radiotherapy, 34% curative and 14% palliative. RT provides 5-year LC benefit in 10.4% of all cancer patients (95% Confidence Interval 9.3, 11.8) and 5-year OS benefit in 2.4% (2.1, 2.7). CRT provides 5-year LC benefit in an additional 0.6% of all cancer patients (0.5, 0.6), and 5-year OS benefit for an additional 0.3% (0.2, 0.4). RT benefit was greatest for head and neck (LC 32%, OS 16%), and cervix (LC 33%, OS 18%). CRT LC benefit was greatest for rectum (6%) and OS for cervix (3%) and brain (3%). Sensitivity analysis confirmed a robust model. INTERPRETATION: Radiotherapy provides significant 5-year LC and OS benefits as part of evidence-based cancer care. CRT provides modest additional benefits.

A Population-based Model of Local Control and Survival Benefit of Radiotherapy for Lung Cancer.

AIMS: To estimate the population-based locoregional control and overall survival benefits of radiotherapy for lung cancer if the whole population were treated according to evidence-based guidelines. These estimates were based on a published radiotherapy utilisation (RTU) model that has been used to estimate the demand and planning of radiotherapy services nationally and internationally. MATERIALS AND METHODS: The lung cancer RTU model was extended to incorporate an estimate of benefits of radiotherapy alone, and of radiotherapy in conjunction with concurrent chemotherapy (CRT). Benefits were defined as the proportional gains in locoregional control and overall survival from radiotherapy over no radiotherapy for radical indications, and from postoperative radiotherapy over surgery alone for adjuvant indications. A literature review (1990-2015) was conducted to identify benefit estimates of individual radiotherapy indications and summed to estimate the population-based gains for these outcomes. Model robustness was tested through univariate and multivariate sensitivity analyses. RESULTS: If evidence-based radiotherapy recommendations are followed for the whole lung cancer population, the model estimated that radiotherapy alone would result in a gain of 8.3% (95% confidence interval 7.4-9.2%) in 5 year locoregional control, 11.4% (10.8-12.0%) in 2 year overall survival and 4.0% (3.6-4.4%) in 5 year overall survival. For the use of CRT over radiotherapy alone, estimated benefits would be: locoregional control 1.7% (0.8-2.4%), 2 year overall survival 1.7% (0.5-2.8%) and 5 year overall survival 1.2% (0.7-1.9%). CONCLUSIONS: The model provided estimates of radiotherapy benefit that could be achieved if treatment guidelines are followed for all cancer patients. These can be used as a benchmark so that the effects of a shortfall in the utilisation of radiotherapy can be better understood and addressed. The model can be adapted to other populations with known epidemiological parameters to ensure the planning of equitable radiotherapy services.

The population benefit of radiotherapy for cervical cancer: local control and survival estimates for optimally utilized radiotherapy and chemoradiation.

PURPOSE: Population benefits of radiotherapy if evidence-based guidelines were routinely followed across the entire population are largely unknown. The aim of this study was to investigate population-based benefits for cervical cancer. METHODS: Overall survival (OS) and local control (LC) benefits were investigated. XRT benefit was defined as the absolute benefit of radiotherapy, over no treatment, for radical indications and defined as the benefit of adjuvant radiation over surgery alone for adjuvant indications. The concurrent chemoradiation (CRT) benefit was the incremental benefit of CRT over XRT. Australian population benefits were modeled using decision trees. Citation databases were systematically queried. Meta-analysis was performed if multiple sources of the same evidence level existed. Robustness of the model assumptions was tested through sensitivity analysis. RESULTS: 53% of all cervix patients had adjuvant or curative radiotherapy indications. 96% were for CRT. The estimated 5-year absolute benefits of optimally utilized radiotherapy alone were: LC: 31% (95% Confidence Interval 29%, 34%), OS: 17% (15%, 18%). These were over and above the contribution of other modalities to outcomes. The incremental 5-year absolute benefits of CRT were: LC 4% (2%, 5%), OS 3% (1%, 5%). In sensitivity analysis, the model was robust. CONCLUSIONS: Optimally utilized radiotherapy provides substantial population OS and LC benefits for cervical cancer. Chemoradiation provides a modest population benefit over XRT. The population-based model was robust.

Factors affecting the use of single-fraction radiotherapy for the palliation of bone metastases in Australia.

AIMS: Palliative radiotherapy for bone metastases remains an important treatment in patients with metastatic malignancy. Previous studies have indicated a reluctance to adopt single-fraction treatment despite considerable evidence. This study aims to describe the factors determining the use of palliative radiotherapy in patients with bone metastases and assess whether fractionation patterns have changed over time with emerging evidence. MATERIALS AND METHODS: A retrospective review of radiotherapy databases at Liverpool/Macarthur Cancer Therapy Centre and the Royal Brisbane and Women's Hospital was conducted for the period 1997-2009. Patients receiving palliative radiotherapy for bony metastases were identified and treatment sites were grouped into 'spine', 'limb', 'multiple' or 'other'. Treatment courses were divided into single- or multiple-fraction treatments. The effects of socioeconomic and geographical factors on radiotherapy utilisation and fractionation were assessed. RESULTS: In total, 5683 patients were identified in the cohort; they received a total of 8211 bone treatments. The overall proportion of single-fraction radiotherapy was 29%, with significant variation over the study period (P < 0.001). Age under 70 years and spine or multiple treatment sites were all associated with lower usage of single-fraction radiotherapy on multivariate analysis. Prostate and lung primary sites were associated with higher usage of single-fraction treatment. The proportion of single-fraction treatment remained low (35%), even for patients who survived less than 22 days from their last treatment. Socioeconomic and geographical factors had little effect on the number of fractions used. CONCLUSIONS: The rate of single-fraction radiotherapy for bone metastases has remained low in two large Australian institutions, despite considerable evidence that single-fraction treatment provides equivalent pain relief to fractionated therapy. This trend towards fractionated treatment was largely maintained, even in patients with limited life expectancy. Further measures to increase the rate of single-fraction therapy are needed.

Evidence-based estimates of the demand for radiotherapy.

There are different methods that may be used to estimate the future demand for radiotherapy services in a population ranging from expert opinion through to complex modelling techniques. This manuscript describes the use of evidence-based treatment guidelines to determine indications for radiotherapy. It also uses epidemiological data to estimate the proportion of the population who have attributes that suggest a benefit from radiotherapy in order to calculate the overall proportion of a population of new cases of cancer who appropriately could be recommended to undergo radiotherapy. Evidence-based methods are transparent and adaptable to different populations but require extensive information about the indications for radiotherapy and the proportion of cancer cases with those indications in the population. In 2003 this method produced an estimate that 52.4% of patients with a registered cancer-type had an indication for radiotherapy. The model was updated in 2012 because of changes in cancer incidence, stage distributions and indications for radiotherapy. The new estimate of the optimal radiotherapy utilisation rate was 48.3%. The decrease was due to changes in the relative frequency of cancer types and some changes in indications for radiotherapy. Actual rates of radiotherapy utilisation in most populations still fall well below this benchmark.

Patterns of retreatment by radiotherapy.

AIMS: To describe patterns of treatment for those who receive more than one episode of megavoltage radiotherapy (retreatment) by cancer type for better service planning and benchmarking. MATERIALS AND METHODS: Institutional databases of all patients who received their first megavoltage radiotherapy for any type of cancer at the Liverpool and Macarthur Cancer Therapy Centres (LM), New South Wales, Australia, Royal Brisbane and Women's Hospital (RBWH), Queensland, Australia and Radiotherapeutic Institution Friesland (RIF), Leeuwarden, the Netherlands, over the period 1991-2009 were examined. Radiotherapy retreatment was defined as any radiotherapy episode, to any body site, after an initial episode of radiotherapy, for the same cancer diagnosis. The total retreatment rate was defined as the number of retreatment episodes of radiotherapy divided by the number of cases in the cohort. RESULTS: In total, 62,270 patients (RBWH 38581, LM 9654, RIF 14035) received 77,762 episodes of radiotherapy, giving a total retreatment rate of 0.25; 52,351 patients (84%) received only one episode of treatment and 9919 (16%) received two or more episodes of treatment. Overall retreatment rates for LM, RBWH and RIF were 0.24, 0.25 and 0.26, respectively. For the five most common cancer types treated, the median time between treatment episodes was longest for breast cancer (11.3 months), then head and neck cancer (9.7 months), colorectal cancer (7.2 months), prostate cancer (4.4 months) and lung cancer (4.1 months). Ninety-one per cent of all fractions were delivered in the first episode of treatment. CONCLUSIONS: The retreatment rate was very similar between the three facilities, suggesting agreement about the indications for retreatment.

Poor outcomes after whole brain radiotherapy in patients with brain metastases: results from an international multicentre cohort study.

AIMS: To describe the characteristics and outcomes of cancer patients receiving Whole Brain Radiotherapy (WBRT) and delineate poor outcome groups after WBRT. MATERIALS AND METHODS: From 1991 to 2007, 3459 patients receiving WBRT for brain metastases at three centres (in Australia and the Netherlands) were retrospectively reviewed. The effect of clinicodemographic factors, including age, gender, primary cancer, time to WBRT from primary cancer diagnosis and WBRT timing relative to other radiotherapy courses on overall survival, survival from WBRT commencement (WBRT-SV) and death within 6 weeks were analysed. RESULTS: WBRT was the first radiotherapy course in 2161/3459 (63%) and the last in 2932/3459 (85%). The most common primary cancer sites with brain metastases were lung (n = 1800; 52%), breast (n = 568; 16%), melanoma (n = 350; 10%) and colorectal (n = 209; 6%). The median time to WBRT from primary cancer diagnosis was 34 weeks, overall survival 1.42 years (0.04-28.70) and WBRT-SV 0.33 years (0-8.60). Older age, male gender and a shorter time from the primary cancer diagnosis to WBRT predicted worse overall survival and WBRT-SV. Seventeen per cent survived less than 6 weeks. Older patients with a shorter time from the primary cancer diagnosis to WBRT and a lower WBRT episode number were more likely to die less than 6 weeks after WBRT. CONCLUSIONS: Cancer patients with brain metastases have poor overall outcomes. High mortality within 6 weeks of starting WBRT suggests patient selection remains challenging.

A comparison of surgical and radiotherapy breast cancer therapy utilization in Canada (British Columbia), Scotland (Dundee), and Australia (Western Australia) with models of "optimal" therapy.

BACKGROUND: Different jurisdictions report different breast cancer treatment rates. Evidence-based utilization models may be specific to derived populations. We compared predicted optimal with actual radiotherapy utilization in British Columbia, Canada; Dundee, Scotland; and Perth, Western Australia. DESIGN: Data were analyzed for differences in demography, tumor, and treatment. Epidemiological data were fitted to published Australian optimal radiotherapy utilization trees and region-specific optimal treatment rates were calculated. Optimal and actual surgery/radiotherapy rates from 2 population-based and 1 institution-based registries were compared for patients diagnosed with breast cancer between 2000 and 2004, and 2002 for British Columbia. RESULTS: Mastectomy rates differed between British Columbia (40%), Western Australia (44%), and Dundee (47%, p<0.01). Radiotherapy rates differed between British Columbia (60%), Western Australia (52%), and Dundee (49%, p<0.01). Actual radiotherapy utilization rates were lower than optimal estimates. Region-specific optimal utilization rates at diagnosis varied from 57% to 71% for radiotherapy and 62% to 64% when taking into account patient preference. Variation was attributed to local differences in demography and tumor stage. CONCLUSIONS: Actual treatment rates varied, and were associated with patterns of care and guideline differences. Actual radiotherapy rates were lower than optimal rates. Differences between optimal and actual utilization may be due to access shortfalls, and patient preference.

Estimation of an optimal chemotherapy utilisation rate for primary malignant brain tumours: an evidence-based benchmark for cancer care.

AIMS: The optimal chemotherapy utilisation rate can serve as a benchmark to assess the quality of cancer care. The aim of this study was to determine the optimal proportion of patients with primary malignant brain tumours for whom there was evidence that they should receive chemotherapy at least once. MATERIALS AND METHODS: An optimal chemotherapy utilisation tree was constructed using indications for chemotherapy identified from evidence-based treatment guidelines. Data on the proportion of patient and tumour-related attributes for which chemotherapy was indicated were obtained and merged with the treatment indications to calculate an optimal chemotherapy utilisation rate. This optimal rate was compared with reported actual rates of chemotherapy utilisation. RESULTS: Chemotherapy is indicated at least once, either as an initial treatment or at recurrence (in those who have not previously received chemotherapy), in 72% of all patients with primary malignant brain tumours. No recent published data on actual chemotherapy utilisation rates were identified for comparison with the optimal rate. CONCLUSION: The optimal chemotherapy utilisation rate can serve as an evidence-based benchmark in the planning and evaluation of chemotherapy services for brain cancer. There are no recent published patterns of care studies that report on chemotherapy utilisation rates for primary malignant brain tumours; future research should focus on filling this gap.

Patterns of retreatment by radiotherapy.

AIM: To describe patterns of radiotherapy retreatment by cancer type in order to develop methods of modelling retreatment for better service planning and benchmarking. MATERIALS AND METHODS: We examined an institutional database of all patients who received their first megavoltage radiotherapy for any type of cancer at the Liverpool and Macarthur Cancer Therapy Centres over the period 1997-2006. The database contains patient demographic data, dates, treatment sites and doses of radiotherapy. The treatment sites were entered as free text and were recoded into a limited number of sites; primary site, bone, brain, soft tissue, other and multiple, so that retreatment sites could be grouped for stratification and analysis. Multiple treatment sites that were part of a single treatment to a primary (for example, primary site and nodes) were recoded as 'primary'. The total retreatment ratio was defined as the number of episodes of radiotherapy divided by the number of cases in the cohort. RESULTS: In the period 1997-2006, 7853 patients had received 9859 episodes of radiotherapy, giving a total retreatment ratio of 26 per 100 patients. In total, 6524 patients (83%) received only one episode of treatment and 1329 received two or more episodes of treatment. The average number of retreatments was 0.26. The tumour type with the highest mean number of retreatments was myeloma (1.05), followed by unknown primary (0.41), lung (0.34) and melanoma (0.32). The lowest mean number of retreatments was for the brain (0.06). The median time between treatment episodes was longest for breast cancer (12.5 months), then colorectal cancer (12.3 months), head and neck cancers (9.0 months), lung cancer (3.8 months) and prostate cancer (5.9 months). CONCLUSION: The retreatment ratio for the cohort was affected by the length of follow-up and by the tumour type. The mean number of retreatments varied from 0.06 for central nervous system malignancy to 1.05 for myeloma, with an average of 0.026.

Estimation of an optimal utilisation rate for palliative radiotherapy in newly diagnosed cancer patients.

AIMS: An optimal utilisation rate for palliative radiotherapy in newly diagnosed cancers will be useful in the planning and delivery of cancer services and has not been reported to date. The aim of this study was to estimate the proportion of new cases of cancer that should receive palliative radiotherapy as their first course of radiotherapy at some time during the course of their illness. MATERIALS AND METHODS: A previously developed model depicting indications for radiotherapy was merged with Australian cancer epidemiological data and re-analysed to identify palliative or radical treatment end points. Palliative radiotherapy end points were further divided by treatment site. The optimal palliative radiotherapy utilisation rates were compared with actual radiotherapy utilisation data for newly diagnosed cancers. RESULTS: Fourteen per cent of all new cancer cases should optimally receive palliative radiotherapy as their first course of radiotherapy treatment. Comparisons with actual radiotherapy utilisation rates from New South Wales, Australia, show that for some common cancers, more newly diagnosed patients receive palliative radiotherapy as their first radiotherapy treatment than would be optimally recommended in this model. This suggests that many patients in New South Wales are not currently being referred for curative treatment. CONCLUSION: Palliative radiotherapy is optimally recommended as the first course of radiotherapy in 14% of all newly diagnosed cancers.

Estimating the referral rate for cancer genetic assessment from a systematic review of the evidence.

To estimate the optimal proportion of new patients diagnosed with cancer who require assessment and evaluation for familial cancer genetic risk, based on the best evidence available. We identified evidence of the patients who require assessment for familial genetic risk when diagnosed with cancer through extensive literature reviews and searches of guidelines. Epidemiological data on the distribution of cancer type, presence of a family history, age and other factors that influence referral for genetic assessment were identified. Decision trees were constructed to merge the evidence-based recommendations with the epidemiological data to calculate the optimal proportion of patients who should be referred. We identified 'high probability' and 'moderate probability' groups for having a genetic susceptibility. The proportion of patients diagnosed with cancer in Australia who have a high probability of having a genetic predisposition and who should be referred for genetic assessment is 1%. If the moderate probability group is also assessed this proportion increases to 6%. This model has identified the proportion of new patients diagnosed with cancer who should be referred for genetic assessment. This data is the first step in determining the resources required for provision of an adequate cancer genetic service.

Technology enhancements and changes in radiotherapy throughput in New South Wales.

AIMS: To assess the effect that the age of linear accelerators and recent changes in technology have had on linear accelerator throughput in New South Wales, Australia. MATERIALS AND METHODS: Duration was measured (time of patient entry into the treatment room to time of exit) of each radiotherapy treatment fraction delivered on each linear accelerator over a 5-day period. Patient-, treatment- and equipment-based variables were collected for all treatment fractions, and assessed for their effect on fraction duration. Comparisons were made between these data and similar productivity data collected from a study carried out in 1996. Since the sample sizes for both the study periods were large enough, the distributions of the means were assumed normal (Central Limit Theorem). Specific analyses were carried out to assess the affect that new technologies, such as automatic field-sequencing (AFS) and multi-leaf collimator (MLC), have had on fraction duration. RESULTS: A total of 12 892 treatment fields and 4316 treatment fractions were delivered on 27 linear accelerators over 135 days. Comparison between the 2003 and 1996 productivity data showed an increase in the mean number of patients treated per hour by 11% and fields treated per hour by 31%. The mean number of fields treated per fraction increased by 15%. The mean fraction duration was reduced by 13% for linear accelerators of less than the median age of 7 years that were equipped with MLC/AFS, or both, compared with older linear accelerators without AFS and MLC. This reduction was more obvious for complex techniques, such as four-field breast treatments (27% decrease in fraction duration). The mean number of fields treated per hour was 43% more on the newer machines equipped with AFS and MLC. CONCLUSIONS: An increase in productivity has been observed between the 1996 and 2003 study periods, as measured by patients or fields per hour, despite an increase in treatment complexity as measured by fields per fraction. The application of AFS and MLC, and the use of newer linear accelerators, significantly shortened the mean duration per fraction for the common treatment techniques.

The development of a new basic treatment equivalent model to assess linear accelerator throughput.

AIMS: The basic treatment equivalent (BTE) model was developed in 1996 in an attempt to improve the measurement of linear accelerator throughput in radiotherapy. This study aimed to assess the effect of treatment set-up and patient characteristics on fraction duration, to update the BTE model and to determine the better throughput measure between fields per hour and BTE per hour. MATERIALS AND METHODS: Stopwatch measurements of the duration of each radiotherapy treatment fraction delivered on each linear accelerator in participating New South Wales radiation oncology departments over a 5-day period in 2003 were undertaken. Patient, equipment and staff data were collected to assess the effect of these variables on fraction duration. A new BTE equation was derived, including the most significant variables. Statistical comparison of fields and BTE per unit time was made to assess the better predictor of fraction duration. RESULTS: Data collected on 27 linear accelerators in 13 departments included a total of 135 days of linear accelerator operation, 4316 fractions and 12 892 treatment fields. Seventeen factors significantly influenced fraction duration (P < 0.01). These accounted for 46% of the total variance in the models. The eight most influential predictors of prolonged fraction duration were included in the BTE model. These were as follows: high number of fields, high number of port films/electronic portal imaging, absence of automatic field-sequencing and multi-leaf collimation, high number of junctions, use of bolus and first fraction of a treatment course. The BTE per hour was shown to be a better predictor of throughput than fields per hour. CONCLUSIONS: The BTE model is a better measure of linear accelerator throughput. It incorporates weightings for treatment and patient factors that significantly influenced fraction duration. This measure could be routinely collected by the radiation oncology departments and included in the electronic radiotherapy information systems.

Comparison of patterns of care in lung cancer in three area health services in New South Wales, Australia.

BACKGROUND: Lung cancer is the leading cause of cancer deaths in New South Wales (NSW). The incidence of and mortality from lung cancer differ throughout different area health services in NSW. AIM: To compare patterns of care in lung cancer among three area health services in NSW. METHODS: South-western Sydney Area Health Service (SWSAHS), Northern Sydney Area Health Service (NSAHS) and Hunter Area Health Service (HAHS) residents diagnosed with lung cancer in 1996 were identified from the NSW Central Cancer Registry and their medical records were reviewed. The main outcome measures were specialist care, investigations, treatment and survival. RESULTS: The study population comprised 256 SWSAHS, 270 NSAHS and 212 HAHS residents. NSAHS residents were older, with a median age of 73 years compared with 68 years in SWSAHS and 70 years in HAHS (P = 0.001). The performance status and stage distributions of the populations were similar. Twenty per cent of HAHS residents did not have a pathological diagnosis compared with 10% in SWSAHS and 9% in NSAHS (P = 0.005). Forty-five per cent of HAHS residents received no treatment compared with 25 and 22% in SWSAHS and NSAHS, respectively (P < 0.001). Despite these differences, there was no significant difference in overall survival. CONCLUSIONS: Lung cancer patterns of care were significantly different among the areas. The variability of practice identified in this study needs to be addressed to ensure optimum care for all patients with lung cancer. Although there was no significant difference in survival, under-utilization of efficacious treatment is likely to have affected patients' quality of life.