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Higher mean lung dose (MLD) in breast cancer patients has been associated with pneumonitis, pulmonary fibrosis and secondary lung cancer primaries. This study examined MLD in a single institution from 2014 to 18 to assess trends in median MLD (Gy) over time and factors associated with higher MLD to determine best practices for limiting lung toxicity. General linear regressions were analysed to determine significant change in median MLD over time in patients receiving conventional or hypofractionated schedules for whole breast/chest wall (WB) radiotherapy with or without sequential boost or simultaneous integrated boost, WB tangential radiotherapy only and WB locoregional radiotherapy. Univariate and multivariable linear regression analysed identified factors associated with MLD. In total, 3894 patients were included in the analysis. The total median MLD across all years was 6.8 Gy in patients treated with conventional fractionation and 3.4 Gy in patients treated with hypofractionation. A significant increase in MLD was observed between 2014 and 2018 in patients receiving conventional or hypofractionation, conventional WB treatment with locoregional radiotherapy, conventional WB radiotherapy with simultaneous integrated boost and hypofractionated WB radiotherapy with sequential boost. Increased MLD was significantly correlated with lower lung volume and larger treatment volume due to locoregional radiotherapy, inclusion of a boost, chest wall treatment and reverse decubitus or supine positioning (P < 0.0001). A significant increase in MLD was observed over the years in patients receiving conventional and hypofractionated radiotherapy. Techniques such as prone positioning should be considered to lower MLD, particularly for patients with predisposing pulmonary risk. • Median mean lung dose (MLD) from 2014–2018 was 6.8 Gy for conventional and 3.4 Gy for hypofractionated radiotherapy (RT). • There was a significant increase in median MLD from 2014 to 2018 in both conventional and hypofractionated RT (p < 0.0001). • Wide tangents, lower lung volume, boost, chest wall, conventional or locoregional RT were associated with higher median MLD. • Prone positioning was significantly associated with lower median MLD than reverse decubitus and supine positioning. [ABSTRACT FROM AUTHOR]

Abstract: Aims: We report a population-based overall survival and prognostic factor analysis specific to adult patients diagnosed with low-grade astrocytoma (LGA). Materials and methods: All histologically confirmed cases of LGA diagnosed between 1992 and 1996 in the province of Ontario, Canada, were identified from the Ontario Cancer Registry and reviewed. Results: In total, 182 patients were identified; the mean age was 50 years and the mean survival time was 4.1 years (standard deviation = 5.1 years). Fifty-four per cent of patients had a surgical excision and 46% were biopsied alone. Both univariate and multivariate analyses showed that patients aged <30 years were significantly more likely to undergo an excision as compared with a biopsy alone (odds ratio = 4.26, 95% confidence interval 1.54–11.77). For the entire cohort, we observed a significant relationship between decreasing survival as a function of increasing age at diagnosis. In the biopsy sub-group, relative to patient's age <30 years, the hazard of dying increased significantly according to age when stratified by decade. However, in those patients having had a primary surgical excision, the hazard of dying relative to patient's age <30 years was similar for those aged 30–49 years and then significantly greater as patient age surpassed 50 years. Conclusions: Age is a significant prognostic factor for LGA. Our analysis suggests that in those patients amenable to a primary tumour excision, a survival benefit may be confined to those under age 50 years. [Copyright &y& Elsevier]

Abstract: Aims: Determination of the risk of recurrence after local excision of ductal carcinoma in situ (DCIS) remains a challenge. Molecular profiling based on immunohistochemical staining to oestrogen receptor (ER), progesterone receptor (PR) and HER2neu improved risk prediction in invasive breast cancer, but few studies have evaluated if molecular classification of DCIS predicts local recurrence. We evaluated the expression of ER, PR and HER2neu in DCIS to determine if molecular classification predicts local recurrence after breast-conserving therapy for DCIS. Materials and methods: We reviewed the records of patients with DCIS treated between 1987 and 2000, carried out a pathology review and immunohistochemical staining for ER, PR and HER2neu and categorised cases into four molecular phenotypes [luminal A (ER+ and/or PR+, HER2neu–), luminal B (ER+ and/or PR+, HER2neu+), HER2neu subtype (ER–, PR–, HER2neu+), triple negative (ER–, PR–, HER2neu–)]. We evaluated the association between the molecular subtype and the development of local recurrence. Results: In total, 180 cases of DCIS were included in the study (luminal A, n =113; luminal B, n =25; HER2neu type, n =29; triple negative, n =13). The median follow-up time was 8.7 years. We observed higher rates of local recurrence among luminal B (40%) and HER2neu type (38%) DCIS compared with luminal A (21%) and triple negative (15%) DCIS. On multivariable analysis, HER2neu overexpression was associated with an increased risk of local recurrence (hazard ratio=1.98; 95% confidence interval: 1.11, 3.53, P =0.02). Conclusion: HER2neu expression in DCIS is a significant predictor of local recurrence, whereas luminal A and triple negative phenotypes are associated with relatively low risks of local recurrence. [Copyright &y& Elsevier]

AIMS: Post-lumpectomy breast radiation is the standard of care for all patient subgroups. However, elderly women with stage I breast cancer on adjuvant tamoxifen therapy have a 4% risk of local recurrence after lumpectomy without adjuvant breast radiation. The purpose of this study was to explore the attitudes of Canadian radiation oncologists who treat breast cancer with respect to their use of adjuvant post-lumpectomy radiotherapy, and their willingness to implement a decision aid for this patient population. MATERIALS AND METHODS: The questionnaire was mailed to 141 Canadian radiation oncologists who treat breast cancer. The respondents were asked to complete an online survey consisting of four parts: (1) demographic information; (2) factors determining post-lumpectomy radiation treatment decisions; (3) hypothetical case scenarios; (4) interest in using a decision aid in their practice. RESULTS: Among the 61 (43%) physicians who completed the survey, there was substantial response variation. After contraindications to radiotherapy, patient overall health and patient preference had the greatest influence on their decision to offer radiotherapy to this patient subgroup. Margin status and use of hormonal therapy were given less importance. For each of the case scenarios, 60-83% of physicians (depending on the case scenario) would offer the patient a choice; far fewer (12-57%) would be comfortable not irradiating. Sixty-four per cent of respondents welcomed the concept of a decision aid for this population. CONCLUSIONS: Although there is significant variation in practice patterns and attitudes among radiation oncologists regarding post-lumpectomy radiotherapy for elderly, low-risk breast cancer patients, the vast majority value patient choice and would be willing to use a decision aid designed for this population in their practice. [ABSTRACT FROM AUTHOR]

Abstract: Aims: Post-mastectomy radiotherapy (PMRT) decreases locoregional recurrence and increases survival for women with large tumours and/or node-positive disease. The American Society of Clinical Oncology has published treatment guidelines, but has also indicated that the optimal technique for PMRT remains unknown. The objective of this study was to evaluate the variability in which a bolus is currently used in PMRT and to identify the clinical situations in which a bolus is used. Materials and methods: In 2004, an e-mail survey was sent to all active physician members of the American Society for Therapeutic Radiology and Oncology, the Canadian Association of Radiation Oncologists and the European Society for Therapeutic Radiology and Oncology. The survey focused on the technical details regarding the use of a bolus in PMRT. Results: In total, 1035 responses were obtained: 642 from the Americas (568 from the USA), 327 from Europe and 66 from Australasia. Respondents from the Americas were significantly more likely to always use a bolus (82%) than the Europeans (31%), as were the Australasians (65%) (P <0.0001). Europeans were significantly more likely to use a bolus for specific indications (P <0.0001). The results also showed wide variation in the schedule of application (every day [33%] and alternate days [46%]) and thickness used (<1cm [35%] and ≥1cm [48%]). Conclusions: There is a wide variation in the use of a bolus in PMRT with significant regional differences. This probably translates into a variation in the dose delivered to the skin and may have an effect on local recurrence and/or toxicity. A randomised clinical trial is needed to evaluate the benefit and toxicity associated with the use of a bolus in PMRT. [Copyright &y& Elsevier]

Aim: To examine changes in radiotherapy (RT) use, cause-specific survival (CSS), and overall survival (OS) in a population-based cohort of Hodgkin''s disease (HD) patients diagnosed from 1982 to 1996.Materials and Methods: Adult patients with HD diagnosed from 1 January 1982 to 31 December 1996 (n=3957) were identified from the Ontario Cancer Registry. The cohort was divided into three consecutive 5-year periods: 1982–1986, 1987–1991, and 1992–1996. RT use, CSS and OS in each of these three periods were compared. For the entire cohort, the cumulative incidence of different causes of death was calculated.Results: The proportion of patients receiving RT within 11 weeks of diagnosis declined over the three consecutive periods (25.1%, 15.6%, 11.7%, P<0.001), as did the proportion receiving RT within 45 weeks (57.0%, 51.0%, 48.1%; P<0.001). There was a significant increase in 5-year CSS over time (81%, 87%, 89%; P<0.001), and OS (72%, 77%, 82%; P<0.001), which remained significant in multivariable analyses. The cumulative incidence of death from causes other than HD was equal to the incidence of HD-related death within 12 years of diagnosis.Conclusions: There was a significant decline in the use of RT as the primary treatment modality and as part of the initial management of HD from 1982–1996 in Ontario. A greater proportion of patients received their RT after a delay consistent with the receipt of prior chemotherapy. There was also a significant increase in the CSS and OS over this period. These findings are in keeping with the adoption of effective chemotherapy in the treatment of HD. [Copyright &y& Elsevier]