Brigid E Hickey

Hypofractionated Whole‐Breast Radiotherapy: Impact on Departmental Waiting Times and Cost

Conventionally fractionated breast radiation therapy is delivered over 5–6 weeks. Randomised evidence has shown that hypofractionated whole‐breast radiotherapy (HWBRT) over 3 weeks results in similar local control without increased toxicity. HWBRT is not standard practice in Australia for all eligible women. We examined the effect of using HWBRT (for eligible patients) on waiting lists and monetary costs. We identified factors associated with prescribing HWBRT. The Princess Alexandra Hospital Radiation Oncology Database was searched for all women with breast cancer treated with adjuvant radiotherapy in 2008. Included patients had undergone breast conserving surgery and had T1‐2N0 tumours with negative margins. Women with large breasts and those receiving nodal irradiation were excluded. The outcome evaluated was fractionation schedule. Patient, tumour and treatment factors associated with the use of HWBRT were examined. The impact on departmental resources and health‐care costs were calculated assuming the entire cohort received HWBRT. Two hundred seventy‐nine patients met the inclusion criteria. Sixty‐seven (24%) of these patients were treated with HWBRT. Compared with the conventionally fractionated breast radiation therapy group, the HWBRT group were older (median 69 vs. 54 years; P < 0.001) and more likely to have smaller tumours (12 mm vs. 15 mm; P = 0.02). Had all eligible patients received HWBRT an extra 14 patients each month could be treated and health‐care costs would be reduced by 24%. HWBRT was more frequently prescribed in older women with small tumours. More widespread use of HWBRT would allow significantly more patients to be treated each month with considerable cost savings.

Multidisciplinary clinic care improves adherence to best practice in head and neck cancer

PURPOSE Multidisciplinary team (MDT) care is widely accepted as best practice for patients with head and neck cancer, although there is little evidence that MDT care improves head and neck cancer related outcomes. This study aims to determine the impact of MDT care on measurable clinical quality indicators (CQIs) associated with improved patient outcomes. MATERIALS AND METHODS Patients treated for head and neck cancer at Ipswich Hospital from 2001 to 2008 were identified. Comparisons were made in adherence to CQIs between patients treated before (pre MDT) and after (post MDT) the introduction of the MDT. Associations were tested using the Chi-square and Whitney U-test. RESULTS Treatment post MDT was associated with greater adherence to CQIs than pre MDT. Post MDT had higher rates of: dental assessment (59% versus 22%, p<.0001), nutritional assessment (57% versus 39%, p=.015), PET staging (41% versus 2%, p<.0001), chemo-radiotherapy (CRT) for locally advanced disease (66% versus 16%, p<.0001) and use of adjuvant CRT for high risk disease (49% versus 16%, p<.0001). The interval between surgery and radiotherapy was shorter in the post MDT group (p=.009) as was the mean length of hospitalization (p=.002). CONCLUSIONS This study highlights the measurable advantages of MDT care over the standard, less formalized, referral process.

Split-course, high-dose palliative pelvic radiotherapy for locally progressive hormone-refractory prostate cancer

PURPOSE Local progression, in patients with hormone-refractory prostate cancer, often causes significant morbidity. Pelvic radiotherapy (RT) provides effective palliation in this setting, with most published studies supporting the use of high-dose regimens. The aim of the present study was to examine the role of split-course hypofractionated RT used at our institution in treating this group of patients. METHODS AND MATERIALS A total of 34 men with locoregionally progressive hormone-refractory prostate cancer, treated with a split course of pelvic RT (45-60 Gy in 18-24 fractions) between 2000 and 2008 were analyzed. The primary endpoints were the response rate and actuarial locoregional progression-free survival. Secondary endpoints included overall survival, compliance, and acute and late toxicity. RESULTS The median age was 71 years (range, 53-88). Treatment resulted in an overall initial response rate of 91%, a median locoregional progression-free survival of 43 months, and median overall survival of 28 months. Compliance was excellent and no significant late toxicity was reported. CONCLUSIONS The split course pelvic RT described has an acceptable toxicity profile, is effective, and compares well with other high-dose palliative regimens that have been previously reported.

The less than whole breast radiotherapy approach.

The addition of conventional whole breast irradiation (WBI) to breast conserving surgery (BCS) reduces the risk of early breast cancer recurrence and leads to a statistically and clinically significant improvement in overall survival. However, the long duration of conventional WBI regimens negatively impacts on quality of life. This has led investigators to evaluate an alternative approach of delivering radiation to a limited volume of tissue around the tumour cavity only (partial breast irradiation) and delivering a larger than standard dose of radiation with each treatment (accelerated partial breast irradiation, APBI). This approach may be achieved by a number of techniques: interstitial brachytherapy, intracavitary brachytherapy using the Mammosite device, intraoperative techniques using electrons or low-energy photons, external beam radiotherapy or permanent seed implant. This articles will review the rationale for the less that whole breast radiotherapy approach and describe the techniques by which it can be achieved and the results obtained to date. Finally, the 7 prospective randomised controlled trials of conventional WBI versus APBI which are open and currently recruiting patients will be discussed.

Over 150 potentially low-value health care practices: an Australian study

597 MJA 198 (11) · 17 June 2013 which increase the risk of type 2 diabetes in offspring — additive to the genetic transmission of diabetogenic traits from mother to child. The newly proposed International Association of the Diabetes and Pregnancy Study Groups (IADSPG) diagnostic criteria for GDM continue to use the oral glucose tolerance test (GTT) but will identify a greater number of women with GDM based on an abnormal fasting, rather than post-load, blood glucose level (BGL). We recently undertook a retrospective review of the results of diagnostic GTTs performed in 10 801 pregnant women between 2008 and 2011 in Western Sydney (at Westmead Hospital, Nepean Hospital, Blacktown Hospital, Auburn Hospital, and Moaven and Partners Pathology [a private pathology service provider]). Based on the older Australasian Diabetes in Pregnancy Society (ADIPS) criteria, 15.7% of results were diagnostic of GDM (4.0% elevated fasting BGL, 13.9% elevated 2-hour BGL, 2.2% both). If the same results are reclassified using IADSPG criteria, 14.6% are diagnostic of GDM (8.6% elevated fasting BGL, 9.2% elevated 2-hour BGL, 3.2% both). We also reviewed the obstetric outcomes of 541 women who attended Blacktown Hospital and had BGLs diagnostic of GDM according to either criteria. Women identified by IADSPG criteria had more macrosomic infants (17.0% v 5.4%), low birthweight infants (11.0% v 6.4%) and babies admitted to the special care nursery (45.5% v 23.2%) compared with women identified using ADIPS cut-offs (all P < 0.05 by the Fisher exact test). In other words, the IADSPG criteria seem to be better at identifying women who will have poor obstetric outcomes. The number diagnosed was no higher in this analysis (although this might change if 1-hour BGL cut-offs were to be included, as proposed by the IADSPG). We argue that GDM remains an important clinical entity, and that it is worth getting the diagnosis right.

A retrospective analysis of survival outcomes for two different radiotherapy fractionation schedules given in the same overall time for limited stage small cell lung cancer

To compare survival outcomes for two fractionation schedules of thoracic radiotherapy, both given over 3 weeks, in patients with limited stage small cell lung cancer (LS‐SCLC).

Efficacy of flattening-filter-free beam in stereotactic body radiation therapy planning and treatment: a systematic review with meta-analysis

A linear accelerator with the flattening‐filter removed generates a non‐uniform dose profile beam. We aimed to analyse and compare plan quality and treatment time between flattened beam (FB) and flattening‐filter‐free (FFF) beam to assess the efficacy of FFF beam for stereotactic body radiation therapy (SBRT). The search strategy was based around 3 concepts; radiation therapy, flattening‐filter‐free and treatment delivery. The years searched were restricted from 2010 to date of review (October 2015). All plan quality comparisons were between FFF and FB plans from the same data sets. We identified 210 potential studies based on the three searched concepts. All articles were screened by two authors for title and abstract and by three authors for full text. Ten studies met the eligibility criteria. Plan quality was evaluated using conformity index (CI), heterogeneity index (HI) and gradient index (GI). Dose to organs‐at‐risk (OAR) and healthy tissues were compared. Differences between beam‐on‐time (BOT) and treatment time (T × T) were also analysed. Normalized percentage ratios of CI and HI demonstrated no clinical differences among the studied articles. GI displayed small variations between the articles favouring FFF beam. The BOT with FFF is substantially reduced, and appears to impact the frequency of intra‐fraction imaging which, in turn, affects total treatment time. Based on planning tumour volume (PTV) coverage, dose to OAR and healthy tissue sparing, FFF beam is clinically effective for the treatment of cancer patients using SBRT. We recommend the use of FFF beam for SBRT based on these factors and the reported overall treatment time reduction.

Intervention quality is not routinely assessed in Cochrane systematic reviews of radiation therapy interventions

The aim of this study was to maximise the benefits from clinical trials involving technological interventions such as radiation therapy. High compliance to the quality assurance protocols is crucial. We assessed whether the quality of radiation therapy intervention was evaluated in Cochrane systematic reviews.

Clinical implications of the overshoot effect for treatment plan delivery and patient-specific quality assurance for step-and-shoot IMRT

In this work, overshoot and undershoot effects associated with step‐and‐shoot IMRT (SSIMRT) delivery on a Varian Clinac 21iX are investigated, and their impact on patient‐specific QA point dose measurements and treatment plan delivery are evaluated. Pinnacle3 SSIMRT plans consisting of 5, 10, and 15 identical 5×5 cm2 MLC defined segments and MU/segment values of 5 MU, 10 MU, and 20 MU were utilized and delivered at 600/300 MU/min. Independent of the number of segments the overshoot and undershoot at 600 MU/min were approximately ±10%,±5%, and ±2.5% for 5 MU/segment, 10 MU/segment, and 20 MU/segment, respectively. At 300 MU/min, each of these values is approximately halved. Interfractional variation of these effects (10 fractions), as well as dosimetric variations for intermediate segments, are reduced at the lower dose rate. QA point‐dose measurements for a sample (n=29) of head and neck SSIMRT beams were on average 2.9% (600 MU/min) and 1.7% (300 MU/min) higher than Pinnacle3 planned doses. In comparison for prostate beams (n=46), measured point doses were 0.8% (600 MU/min) and 0.4% (300 MU/min) higher. The reduction in planned‐measured point‐dose discrepancies at 300 MU/min can be attributed in part to the inclusion of the first segment (overshoot) in the admixture of segments that deliver measured dose. Pinnacle3 plans for 10/9 head and neck/prostate treatments were adjusted by ±0.5 MU to include the effects of overshoot and undershoot at 600 MU/min. Comparing original and adjusted plans for each site indicated that the original plan was preferred in 70% and 89% of head and neck and prostate cases, respectively. The disparity between planned and delivered treatment that this suggests can potentially be mitigated by treating SSIMRT at a dose rate below 600 MU/min. PACS number(s): 87.55.Qr, 87.56.bd, 87.56.N‐In this work, overshoot and undershoot effects associated with step-and-shoot IMRT (SSIMRT) delivery on a Varian Clinac 21iX are investigated, and their impact on patient-specific QA point dose measurements and treatment plan delivery are evaluated. Pinnacle3 SSIMRT plans consisting of 5, 10, and 15 identical 5×5 cm2 MLC defined segments and MU/segment values of 5 MU, 10 MU, and 20 MU were utilized and delivered at 600/300 MU/min. Independent of the number of segments the overshoot and undershoot at 600 MU/min were approximately ±10%,±5%, and ±2.5% for 5 MU/segment, 10 MU/segment, and 20 MU/segment, respectively. At 300 MU/min, each of these values is approximately halved. Interfractional variation of these effects (10 fractions), as well as dosimetric variations for intermediate segments, are reduced at the lower dose rate. QA point-dose measurements for a sample (n=29) of head and neck SSIMRT beams were on average 2.9% (600 MU/min) and 1.7% (300 MU/min) higher than Pinnacle3 planned doses. In comparison for prostate beams (n=46), measured point doses were 0.8% (600 MU/min) and 0.4% (300 MU/min) higher. The reduction in planned-measured point-dose discrepancies at 300 MU/min can be attributed in part to the inclusion of the first segment (overshoot) in the admixture of segments that deliver measured dose. Pinnacle3 plans for 10/9 head and neck/prostate treatments were adjusted by ±0.5 MU to include the effects of overshoot and undershoot at 600 MU/min. Comparing original and adjusted plans for each site indicated that the original plan was preferred in 70% and 89% of head and neck and prostate cases, respectively. The disparity between planned and delivered treatment that this suggests can potentially be mitigated by treating SSIMRT at a dose rate below 600 MU/min. PACS number(s): 87.55.Qr, 87.56.bd, 87.56.N.