Right-sided vocal cord paralysis following stereotactic body radiation therapy for non-small-cell lung cancer: A case report.

Vocal code paralysis (VCP) is a rare complication of stereotactic body radiation therapy (SBRT). In most previously reported cases of VCP after SBRT, VCP was left-sided because of anatomic vulnerability. Here, we report a case of right-sided VCP following SBRT for non-small-cell lung cancer. The patient was an 81-year-old man who underwent SBRT for synchronous lung cancer of the right upper and inferior lobes. He subsequently developed radiation pneumonitis and received corticosteroids. Lung contraction persisted, and the mediastinum shifted to the right because of lung volume reduction. After corticosteroids discontinuation, the patient developed hoarseness and voice weakness. An endoscopic test showed right-sided VCP. Imaging examinations did not reveal new lesions, including lung cancer recurrence. Therefore, we diagnosed the patient with SBRT-associated VCP and speculated that the injury to the right vagal nerve and recurrent laryngeal nerve resulted from mechanical traction due to intense lung contraction, which might have induced VCP. We should be alert to VCP following SBRT, even if the target lesions are right-sided.