Jaruchinda Pariyanan, Jindavijak Somjin, Singhavarach Natchavadee
Department of Otolaryngology, Phramongkutklao College ofMedicine, Bangkok, Thailand.
J Med Assoc Thai. 2012 May;95 Suppl 5:S23-8.
Recurrent laryngeal nerve damage is a rare complication after receiving conventional radiotherapy for treatment of head and neck cancers and will always be underestimated. The purpose of the present study was to focus on the prevalence of vocal cord paralysis after irradiation and the natural history in those patients.
All patients who received more than 60 Gy radiation dose of convention radiotherapy for treatment of head and neck carcinoma from Phramongkutklao Hospital and Nation Cancer Institute of Thailand were recruited in the present study duringfollow-up period between May 2006-December 2007. The subjects had to have good mobility of bilateral vocal cords with no recurrence or persistent tumor before the enrollment. Baseline characteristic and the associated symptoms of the recurrent laryngeal nerve paralysis were recorded. Laryngeal examinations were done byfiberoptic laryngoscope and in suspicious cases; stroboscope and/or laryngeal electromyography were also performed. The vocal fold paralysis was diagnosed by reviewing recorded VDO by 2 laryngologist who were not involved in the present study.
70 patients; 51 male and 19female were recruited. 5 patients (7.14%) were diagnosed to have vocal cord paralysis and 2 patients (2.86%) were found to have vocal cord paresis confirmed by electromyography. Most of them were the patients with nasopharyngeal cancers (6/7) with the only one had oropharyngeal cancer (1/7). All of the paralysis/paresis was unilateral lesion; 4 on the left and 3 on the right side. The duration from the patients completed radiotherapy to the time of the diagnosis of vocal cord palsy was 14-35 months. The measure of agreement or Kappa value with 95% CI was 0.818 +/- 0.245. Associated symptoms of vocal cord palsy are hoarseness (100%), dysphagia (28.6%) and aspiration (28.6%).
A significant number of vocal fold palsy may occur in patients with head and neck carcinoma after receiving conventional radiotherapy. Subcutaneous fibrosis or compromised blood vessels at the skull base or the neck area may be important risk factors for development of the complications and further studies are need to solve the pathogenesis.
喉返神经损伤是头颈部癌症接受传统放疗后罕见的并发症，且一直未得到充分重视。本研究旨在关注放疗后声带麻痹的发生率及这些患者的自然病史。
本研究纳入了2006年5月至2007年12月随访期间，来自泰国诗里拉吉医院和泰国国立癌症研究所，接受超过60 Gy传统放疗剂量治疗头颈部癌的所有患者。受试者在入组前双侧声带必须具有良好的活动度，且无肿瘤复发或残留。记录喉返神经麻痹的基线特征及相关症状。通过纤维喉镜进行喉部检查，对于可疑病例，还进行频闪喉镜检查和/或喉肌电图检查。由两名未参与本研究的喉科医生通过回顾记录的视频动态喉镜（VDO）来诊断声带麻痹。
共招募了70例患者，其中男性51例，女性19例。5例（7.14%）被诊断为声带麻痹，2例（2.86%）经肌电图证实为声带轻瘫。大多数患者为鼻咽癌患者（6/7），仅有1例为口咽癌患者（1/7）。所有麻痹/轻瘫均为单侧病变，左侧4例，右侧3例。从患者完成放疗到诊断出声带麻痹的时间为14至35个月。一致性测量或Kappa值及95%置信区间为0.818±0.245。声带麻痹的相关症状包括声音嘶哑（100%）、吞咽困难（28.6%）和误吸（28.6%）。
头颈部癌患者接受传统放疗后可能会出现相当数量的声带麻痹。皮下纤维化或颅底或颈部区域血管受损可能是并发症发生的重要危险因素，需要进一步研究以阐明其发病机制。
