West Katrina, Schneider Michal, Wright Caroline, Beldham-Collins Rachael, Coburn Natalie, Tiver Ken, Gebski Val, Stuart Kirsty E
Nepean Cancer Care Centre, Nepean Blue Mountains Local Health District, Penrith, New South Wales, Australia.
Crown Princess Mary Cancer Centre, Western Sydney Local Health District, Wentworthville, New South Wales, Australia.
J Med Imaging Radiat Oncol. 2020 Feb;64(1):113-119. doi: 10.1111/1754-9485.12943. Epub 2019 Sep 4.
The aim of this study was to determine dosimetric factors, such as mean dose and oesophageal length, which may influence the incidence and severity of oesophagitis in breast cancer patients receiving radiotherapy to the supraclavicular nodes.
This was a single-arm prospective observational study. Toxicity grading was undertaken twice weekly to determine the onset of grade 2 oesophagitis in consecutive patients prescribed IMRT to the breast or chest wall and supraclavicular fossa (SCF) nodes. Recorded variables included mean and maximum doses to the oesophagus, oesophageal length and pharynx length within the treatment area. Multivariate logistic regression and Fishers' exact test were used with a 0.05 significance level to compare the onset of grade 2 oesophagitis with these variables.
A total of 77 patients were included in the study. Twenty-four (31%) patients reported grade 2 oesophagitis. There was a higher incidence of grade 2 oesophagitis in patients receiving a mean oesophageal dose of ≥31 Gy compared to those receiving < 31 Gy (18/24 versus 6/24, respectively, P = 0.025). There was a significant difference in the onset of grade 2 toxicity in patients who had ≥ 1 cm of pharynx included in SCF fields compared with those with <1 cm (15/24 versus 9/24, respectively, P = 0.0116). The odds ratios for developing grade 2 oesophagitis were 3.2 (95% CI = 1.05-9.62, P = 0.04) for a mean dose of ≥31 Gy and 3.4 (95% CI = 1.19-9.5, P = 0.022) for ≥1 cm of pharynx in the SCF field.
By limiting the mean dose to the irradiated oesophagus to <31 Gy during the planning process and ensuring that <1 cm of pharynx is included in the radiation field, oesophageal toxicity may be minimised.
本研究旨在确定剂量学因素，如平均剂量和食管长度，这些因素可能会影响接受锁骨上淋巴结放疗的乳腺癌患者食管炎的发生率和严重程度。
这是一项单臂前瞻性观察研究。对连续接受乳房或胸壁及锁骨上窝（SCF）淋巴结调强放疗（IMRT）的患者，每周进行两次毒性分级，以确定2级食管炎的发病情况。记录的变量包括食管的平均剂量和最大剂量、食管长度以及治疗区域内的咽部长度。采用多因素逻辑回归和Fisher精确检验，显著性水平为0.05，比较2级食管炎的发病情况与这些变量之间的关系。
本研究共纳入77例患者。24例（31%）患者报告发生2级食管炎。接受食管平均剂量≥31 Gy的患者2级食管炎的发生率高于接受<31 Gy的患者（分别为18/24和6/24，P = 0.025）。SCF野中包含≥1 cm咽部的患者与<1 cm的患者相比，2级毒性的发病情况有显著差异（分别为15/24和9/24，P = 0.0116）。食管平均剂量≥31 Gy时发生2级食管炎的比值比为3.2（95%置信区间=1.05 - 9.62，P = 0.04），SCF野中咽部≥1 cm时为3.4（95%置信区间=1.19 - 9.5，P = 0.022）。
在计划过程中，将照射食管的平均剂量限制在<31 Gy，并确保放疗野中包含的咽部<1 cm，可使食管毒性降至最低。
