Department of Radiation Oncology, University Hospital of Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany.
Heidelberg Institute of Radiation Oncology (HIRO), 69120, Heidelberg, Germany.
Head Face Med. 2022 Feb 26;18(1):7. doi: 10.1186/s13005-022-00311-8.
Osteoradionecrosis (ORN) of the lower jaw is a serious late complication after radiotherapy in patients with oral cavity cancer. The aim of this study is to generate more insight into which patient- and treatment-related factors are associated with the development of ORN in oral cavity cancer patients undergoing postoperative radiotherapy.
Retrospective evaluation and comparison of 44 patients with ORN (event group 1) matched according to 45 patients without ORN (control group 2) who received postoperative radiotherapy of oral cavity squamous cell carcinoma at our institution between 2012 and 2020. Dosimetric factors that favor the occurrence of ORN should be detected. The cumulative occurrence rate of ORN was calculated according to the Kaplan-Meier method and analyzed by Cox regression and log-rank test.
The median time to develop ORN was 18 months (3-93 months) after radiotherapy. Dental status before radiotherapy (RT) treatment (HR 4.5; 1.8-11.5) and dosimetric parameters including Dmean > 45 Gy (HR 2.4; 1.0-5.7), Dmax > 60 Gy (HR 1.3; 1.1-2.8) and planning target volume (PTV) proportion > 40% intersection with the lower jaw (HR 1.1; 1.0-1.1) were significantly associated with ORN.
The results of this retrospective study reveal that oral cavity cancer patients who underwent pre-RT dental surgery as well as dosimetric parameters using Dmax > 60 Gy, higher mean doses > 45 Gy and more than 40% PTV intersection with the lower jaw bone are independent risk factors for ORN. These findings can assist in the management of patients undergoing RT for head and neck cancer regarding ORN prevention.
Poor oral hygiene and desolate dental status as well as high radiation doses to the mandibular bone significantly increase the risk of developing osteoradionecrosis. Before irradiating a patient with oral cavity cancer, an appointment with the dentist should be made and teeth sanitized if necessary. Likewise, maximum radiation doses to the lower jaw should be minimized.
下颌骨放射性骨坏死（ORN）是口腔癌患者放疗后的一种严重的迟发性并发症。本研究旨在深入了解哪些与患者和治疗相关的因素与接受术后放疗的口腔癌患者 ORN 的发生有关。
回顾性评估和比较 2012 年至 2020 年期间在我院接受口腔鳞状细胞癌术后放疗的 44 例 ORN 患者（事件组 1）与根据 45 例无 ORN 患者（对照组 2）的情况。应检测有利于 ORN 发生的剂量学因素。根据 Kaplan-Meier 方法计算 ORN 的累积发生率，并通过 Cox 回归和对数秩检验进行分析。
放射治疗后发生 ORN 的中位时间为 18 个月（3-93 个月）。放射治疗前的牙齿状况（RT）（HR 4.5；1.8-11.5）和剂量学参数，包括 Dmean>45Gy（HR 2.4；1.0-5.7）、Dmax>60Gy（HR 1.3；1.1-2.8）和计划靶区（PTV）与下颌骨的交集比例>40%（HR 1.1；1.0-1.1）与 ORN 显著相关。
这项回顾性研究的结果表明，接受放射治疗前牙科手术以及使用 Dmax>60Gy、更高平均剂量>45Gy 和 PTV 与下颌骨的交集比例超过 40%等剂量学参数的口腔癌患者是 ORN 的独立危险因素。这些发现可以帮助管理接受头颈部癌症放射治疗的患者，以预防 ORN。
口腔卫生不良和牙齿状况不佳以及下颌骨接受高剂量辐射会显著增加发生放射性骨坏死的风险。在对口腔癌患者进行放射治疗之前，应安排与牙医预约，如果需要，应进行牙齿清洁。同样，应尽量减少下颌骨的最大辐射剂量。
