Department of Radiation Oncology, Netherlands Cancer Institute/Antoni van Leeuwenhoek, Amsterdam, The Netherlands.
Department of Biometrics, Netherlands Cancer Institute/Antoni van Leeuwenhoek, Amsterdam, The Netherlands.
Cancer Treat Rev. 2017 Sep;59:102-108. doi: 10.1016/j.ctrv.2017.07.004. Epub 2017 Jul 21.
The head and neck region has rich regional lymphatic network, with a theoretical risk on contralateral metastasis from oropharyngeal cancer (OPC). There is a long-standing convention to irradiate the great majority of these tumors electively to both sides of the neck to reduce the risk of contralateral regional failure (cRF), but this can induce significant toxicity. We aimed to identify patient groups where elective contralateral irradiation may safely be omitted.
PubMed and EMBASE were searched for original full-text articles in English with a combination of search terms related to the end points: cRF in OPC primarily treated by radiotherapy only to the ipsilateral neck and identifying predictive factors for increased incidence of cRF. The data from the identified studies were pooled, the incidence of cRF was calculated and the correlation with different predictive factors was investigated.
Eleven full-text articles met the inclusion criteria. In these studies, 1116 patients were treated to the ipsilateral neck alone. The mean incidence of cRF was 2.42% (range 0-5.9%, 95% CI 1.6-3.5%). The incidence of cRF correlated only with T-stage (p=0.008), and involvement of midline (p=0.001). However, the significant correlation with T-stage can be explained by the very low incidence of cRF among T1 (0.77%), and disappeared when the incidence of cRF was compared between T2, T3,and T4 (p=0.344).
The incidence of cRF in patients with OPC is very low, with involvement of midline providing the most significant prognosticator. These results call for trials on unilateral elective irradiation in selected groups.
头颈部区域拥有丰富的区域性淋巴网络，理论上存在口咽癌（OPC）对侧转移的风险。长期以来，人们一直认为有必要对绝大多数这些肿瘤进行双侧颈部选择性照射，以降低对侧区域失败（cRF）的风险，但这可能会导致严重的毒性。我们旨在确定可以安全省略选择性对侧照射的患者群体。
通过结合与终点相关的搜索词，在 PubMed 和 EMBASE 上搜索英文原始全文文章：主要通过同侧颈部放疗治疗的 OPC 患者的对侧区域失败（cRF），并确定增加 cRF 发生率的预测因素。对确定的研究中的数据进行汇总，计算 cRF 的发生率，并研究其与不同预测因素的相关性。
符合纳入标准的全文文章有 11 篇。在这些研究中，有 1116 名患者仅接受同侧颈部治疗。cRF 的平均发生率为 2.42%（范围 0-5.9%，95%CI 1.6-3.5%）。cRF 的发生率仅与 T 分期相关（p=0.008），且与中线受累相关（p=0.001）。然而，T 分期与 cRF 发生率的显著相关性可以用 T1 期 cRF 的发生率非常低（0.77%）来解释，当比较 T2、T3 和 T4 期的 cRF 发生率时，这种相关性消失（p=0.344）。
OPC 患者的 cRF 发生率非常低，中线受累是最重要的预后因素。这些结果呼吁在选定的患者群体中开展单侧选择性照射的试验。
