Department of Radiotherapy, Erasmus MC Cancer Institute, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands; Department of Oral and Maxillofacial Surgery, Erasmus MC Cancer Institute, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands; Da Vinci Clinic Rotterdam, Brielselaan 69, 3081 AA Rotterdam, The Netherlands.
Department of Oral and Maxillofacial Surgery, Erasmus MC Cancer Institute, University Medical Center Rotterdam, Dr. Molewaterplein 40, 3015 GD Rotterdam, The Netherlands.
Oral Oncol. 2022 Oct;133:106056. doi: 10.1016/j.oraloncology.2022.106056. Epub 2022 Aug 4.
Osteoradionecrosis (ORN) is a severe late complication after radiotherapy but current knowledge on ORN risks in the setting of postoperative radiotherapy (PORT) is limited. We studied the incidence and risk factors of ORN in patients with oral cavity cancers (OCC, treated with PORT.
A retrospective cohort study was conducted including OCC patients (mainly squamous cell) treated with postoperative intensity modulated radiotherapy between 2010 and 2018 with > 1 year disease-free survival. Cumulative incidences of ORN were computed using the Kaplan Meier method. Clinical and dosimetric risk factors for mandibular ORN were evaluated using Cox regression models.
Within our cohort (N = 227, median follow-up 49 months) we observed 46 cases of ORN, mainly in the mandible (n = 41). The cumulative incidence of mandibular ORN was 15.9 % (SE 2.5 %) at three years and 19.8 % (SE 3.0 %) at five years. At univariable analysis, smoking, mandibular mandibulotomy or segment resection, mean dose to the mandible, and mandible volume (%) ≥ 60 Gy (V60) were significantly associated with increased ORN risks. At multivariable analysis, smoking (HR 2.13, 95 %CI 1.12-4.06) and V60 (HR 1.02 per 1 % increase, 95 %CI 1.01-1.04) remained predictive factors. For active smokers with a high V60 ≥ 40 % we observed rapid ORN development with a 1-year incidence of 29 % vs 6 % for others (p < 0.01).
OCC Patients treated with PORT are at high risk for mandibular ORN. We identified the mandibular volume receiving ≥ 60 Gy as the dominant risk factor, especially in active smokers. Limiting high-dose volumes at treatment planning may decrease ORN risks.
放射性骨坏死（ORN）是放疗后的一种严重迟发性并发症，但目前对术后放疗（PORT）背景下 ORN 风险的了解有限。我们研究了接受 PORT 治疗的口腔癌（OCC）患者发生 ORN 的发生率和危险因素。
进行了一项回顾性队列研究，纳入了 2010 年至 2018 年间接受术后调强放疗且无病生存时间超过 1 年的 OCC 患者（主要为鳞状细胞癌）。使用 Kaplan-Meier 法计算 ORN 的累积发生率。使用 Cox 回归模型评估下颌骨 ORN 的临床和剂量学危险因素。
在我们的队列中（N=227，中位随访时间 49 个月），我们观察到 46 例 ORN，主要发生在下颌骨（n=41）。下颌骨 ORN 的 3 年累积发生率为 15.9%（SE 2.5%），5 年累积发生率为 19.8%（SE 3.0%）。单变量分析显示，吸烟、下颌骨部分切除术或节段切除术、下颌骨平均剂量和下颌骨体积（%）≥60Gy（V60）与 ORN 风险增加显著相关。多变量分析显示，吸烟（HR 2.13，95%CI 1.12-4.06）和 V60（HR 每增加 1%，95%CI 1.01-1.04）仍然是预测因素。对于 V60≥40%的活跃吸烟者，我们观察到 ORN 迅速发展，1 年发生率为 29%，而其他患者的发生率为 6%（p<0.01）。
接受 PORT 治疗的 OCC 患者下颌骨 ORN 风险较高。我们发现下颌骨接受≥60Gy 剂量的体积是主要的危险因素，尤其是在活跃吸烟者中。在治疗计划中限制高剂量体积可能会降低 ORN 风险。
