Department of Clinical Oncology, Velindre Cancer Centre, Cardiff, UK; Department of Clinical Oncology, Addenbrooke's Hospital, Cambridge, UK.
Department of Clinical Oncology, Velindre Cancer Centre, Cardiff, UK.
Clin Oncol (R Coll Radiol). 2021 Aug;33(8):536-545. doi: 10.1016/j.clon.2021.03.011. Epub 2021 Apr 17.
Pelvic radiotherapy adds significantly to the curative treatment of many pelvic malignancies. However, this cure comes at a cost for many patients, where late bowel toxicities, such as faecal incontinence, urgency and diarrhoea, adversely affect quality of life. Despite the implementation of advanced radiotherapy techniques in many centres, there are deficiencies in our knowledge of how to make best use of these techniques to minimise these late toxicities, with dose-volume constraints specifically for late effects needing definition. The aims of this study were to establish dose-volume predictors for patient-reported late bowel toxicities and derive constraints for clinical use to reduce the risk of these toxicities.
All radiotherapy patients treated in our institution between 2012 and 2014 for gynaecological and urological cancers (bladder, prostate where pelvic nodes are treated) were identified. Patients were sent patient-reported toxicity questionnaires at 12 and 24 months after treatment. Planning computed tomography scans were retrospectively contoured with different definitions of bowel as organs at risk (OARs). Dose-volume data for each OAR were collected and predictors of these toxicities found using multivariate analysis. For those dose-volume predictors found to be significant on multivariate analysis, statistically significant and clinically relevant dose-volume constraints were derived. Furthermore, data collected were used to validate constraints from published studies.
Faecal urgency, incontinence and diarrhoea rates were found in 52, 23.5 and 18.7% of the 203 patients included at 12 months following radiotherapy. Dose-volume parameters for sigmoid colon and large bowel were significant for these toxicities, and constraints for these OARs were derived, which are promising. A previously published constraint for bowel loops was validated with our data.
The sigmoid colon and large bowel are important OARs for the development of faecal urgency, incontinence and diarrhoea. Promising constraints for these OARs were derived, which require further validation before prospective clinical use.
盆腔放疗显著提高了许多盆腔恶性肿瘤的治愈率。然而，对于许多患者来说，这一治疗效果是有代价的，因为晚期肠道毒性，如粪便失禁、尿急和腹泻，会对生活质量产生不利影响。尽管许多中心都采用了先进的放疗技术，但我们对如何充分利用这些技术来最大限度地减少这些晚期毒性的了解仍存在不足，具体来说，就是需要确定晚期效应的剂量-体积限制。本研究的目的是确定患者报告的晚期肠道毒性的剂量-体积预测因子，并得出用于临床的约束条件，以降低这些毒性的风险。
回顾性地分析了 2012 年至 2014 年间在我们机构接受妇科和泌尿科（膀胱癌、前列腺癌，其中包括盆腔淋巴结治疗）治疗的所有放疗患者。在治疗后 12 个月和 24 个月时，患者被发送患者报告的毒性问卷。对计划 CT 扫描进行了回顾性勾画，不同的定义将肠道作为危及器官（OAR）。收集了每个 OAR 的剂量-体积数据，并使用多变量分析找到了这些毒性的预测因子。对于多变量分析发现具有统计学意义的剂量-体积预测因子，得出了具有统计学意义和临床相关性的剂量-体积约束。此外，还使用收集到的数据验证了来自已发表研究的约束条件。
在 203 名接受放疗 12 个月后的患者中，分别有 52%、23.5%和 18.7%的患者出现粪便急迫、失禁和腹泻。乙状结肠和大肠的剂量-体积参数与这些毒性相关，并且为这些 OAR 得出了约束条件，这些约束条件具有一定的前景。我们的数据验证了之前发表的肠袢约束条件。
乙状结肠和大肠是导致粪便急迫、失禁和腹泻的重要 OAR。为这些 OAR 得出了有前景的约束条件，这些约束条件需要进一步验证后才能用于前瞻性临床应用。
