Impact of tumour bed boost integration on acute and late toxicity in patients with breast cancer: A systematic review

The purpose of this systematic review was to summarise the evidence from studies investigating the integration of tumour bed boosts into whole breast irradiation for patients with Stage 0-III breast cancer, with a focus on its impact on acute and late toxicities. A comprehensive systematic electronic search through the Ovid MEDLINE, EMBASE and PubMed databases from January 2000 to January 2015 was conducted. Studies were considered eligible if they investigated the efficacy of hypo- or normofractionated whole breast irradiation with the inclusion of a daily concurrent boost. The primary outcomes of interest were the degree of observed acute and late toxicity following radiotherapy treatment. Methodological quality assessment was performed on all included studies using either the Newcastle–Ottawa Scale or a previously published investigator-derived quality instrument. The search identified 35 articles, of which 17 satisfied our eligibility criteria. Thirteen and eleven studies reported on acute and late toxicities respectively. Grade 3 acute skin toxicity ranged from 1 to 7% whilst moderate to severe fibrosis and telangiectasia were both limited to 9%. Reported toxicity profiles were comparable to historical data at similar time-points. Studies investigating the delivery of concurrent boosts with whole breast radiotherapy courses report safe short to medium-term toxicity profiles and cosmesis rates. Whilst the quality of evidence and length of follow-up supporting these findings is low, sufficient evidence has been generated to consider concurrent boost techniques as an alternative to conventional sequential techniques.     

Hippocampal-sparing radiotherapy: The new standard of care for World Health Organization grade II and III gliomas?

The neurocognitive effects of cranial radiotherapy in patients with gliomas are well-recognised and may be related to the dose delivered to the hippocampi. Intensity modulated radiotherapy (IMRT) is a radiotherapy technique that can be used to selectively spare the hippocampi without compromising the dose delivered to the tumour. This study aimed to evaluate if hippocampal-sparing IMRT is achievable in patients with World Health Organization (WHO) grade II and III gliomas. A retrospective review of consecutive patients with WHO grade II and III gliomas treated with IMRT at our institution between January 2009 and August 2012 was performed. Hippocampal-sparing was defined as a mean dose to at least one hippocampus of less than 30 Gy. The dose delivered to the tumour was never compromised to achieve the hippocampal dose constraint. Logistic regression analyses were performed to identify predictive factors for achieving hippocampal-sparing treatment. Eighteen patients were identified and hippocampal-sparing was achieved in 14 (78%). The median dose prescribed was 59.4 Gy in 33 fractions and 11 patients had WHO grade III gliomas. The mean dose to the contralateral hippocampus was 24.9 Gy. Planning target volumes less than 420.5 cm³ were more likely to enable hippocampal-sparing treatment to be given (hazard ratio 1.7, p = 0.03) and there was a trend with oligodendrogliomas and anaplastic oligodendrogliomas. Hippocampal-sparing radiotherapy is feasible in patients with WHO grade II and III gliomas. Oncologic outcomes are yet to be assessed prospectively. The relationship between hippocampal dose and neurocognitive function in adults is currently under investigation.     

调强放疗联合腔内后装放疗治疗晚期宫颈癌的临床研究

目的探讨调强放疗联合腔内后装放疗治疗晚期宫颈癌的临床效果。方法选取我院收治的晚期宫颈癌患者48例,随机均分为对照组和实验组,对照组行常规放疗联合腔内后装放疗治疗,实验组行调强放疗（IMRT）联合腔内后装放疗治疗。观察比较两组患者放疗疗效及骨髓抑制、放射性膀胱炎、放射性直肠炎、放射性皮炎等不良反应发生率。结果实验组患者放疗总缓解率为91．7％（22／24）,显著高于对照组的66．7％（16／24）（P〈0．05）。实验组患者骨髓抑制、放射性膀胱炎、放射性直肠炎等并发症发生率分别为29．2％,33．3％,0．0％,均显著低于对照组患者（P〈0．05）。实验组患者放射性皮炎发生率为O．0％,对照组为16．7％,组间比较差异无统计学意义（P〉0．05）。结论调强放疗联合腔内后装放疗治疗晚期宫颈癌临床疗效确切,能有效减少并发症的发生,值得广泛推广使用。     

IMRT计划在不同加速器上互换执行的可行性

目的：探讨调强放疗（IMRT）计划在不同多叶光栅（MLC）叶片宽度配置的加速器上互换执行的可行性。方法将设计在EX加速器上执行的5例鼻咽癌IMRT（SW）计划,不进行重新优化和计算,直接移植到IX加速器上执行;以及通过治疗计划系统（TPS）模拟在IX加速器执行1、2、3、4、5、10次后再返回EX加速器继续执行,用剂量体积直方图（DVH）分析和评估靶区和危及器官的剂量体积参数的变化。结果将EX加速器的IMRT计划完全移植到IX加速器执行,以及在IX加速器执行1、2、3、4、5、10次后再返回至EX加速器继续执行时,靶区和危及器官的剂量体积参数发生了一定程度的变化,前者的变化更大。结论若两台加速器产自同一个厂家,且能量配置和治疗时的机械参数相同时,当一台加速器发生故障且短时间内无法修复时,可以将其治疗计划移植至另一台加速器上执行（5次以内）,待故障加速器修复后再返回原计划加速器执行。     

Practical considerations in reducing swallowing dysfunction following concurrent chemoradiotherapy with intensity‐modulated radiotherapy for head and neck cancer

Data have emerged that the addition of concurrent chemotherapy to radiation can lead to swallowing dysfunction that may have an impact on patient quality of life and lead to significant morbidities such as poor nutritional status, enteral feeding tube dependence, and aspiration pneumonia. Although intensity‐modulated radiation therapy (IMRT) for head and neck cancer was initially developed to spare the parotid gland to reduce xerostomia, attention has recently focused on its utility to selectively decrease radiation dose to specified anatomic structures responsible for a functional swallow. Recent reports have proposed a variety of dose thresholds or constraints to these swallowing‐related structures, which may guide IMRT planning with the aim of reducing dysphagia. This critical review of the current literature assesses the feasibility of IMRT to maintain swallowing function and appraises the various dosimetric parameters that have been proposed to help minimize long‐term dysphagia. © 2013 Wiley Periodicals, Inc. Head Neck 36: 291–298, 2014