Invasive Insular Thyroid Carcinoma Presenting as Nonparalytic Dysphonia

Patients with suspected thyroid malignancy often undergo preoperative laryngeal examination with a focus on vocal fold mobility. We present the unique case of a patient with invasive thyroid carcinoma who presented with dysphonia despite intact vocal fold motion. A 73-year-old female with a remote thyroid lobectomy presented with dysphonia. Thyroid ultrasound and fine-needle aspiration revealed a 1.1-cm nodule consistent with a colloid cyst. Videostroboscopy demonstrated mild laryngeal stenosis at the glottis and infraglottis with no evidence of paralysis. After failed medical therapy, the patient underwent microlaryngoscopy with biopsy of her infraglottic fullness, with histopathology reporting squamous epithelium without nucelar atypia. After several weeks of worsening dysphonia and persistent infraglottic fullness, she underwent repeat microlaryngoscopy with biopsy. On postoperative day 1, she developed dyspnea and stridor refractory to maximal medical management. To secure the airway, she underwent an awake tracheostomy, during which the thyroid isthmus was found to be densely adherent to the larynx. Histopathology identified insular thyroid carcinoma. Subsequent imaging confirmed a large, invasive thyroid tumor. Further workup revealed metastases to the bone and liver. The patient underwent a successful palliative resection of the thyroid followed by neck radiation and received palliative spinal surgery with adjuvant radiation. A clinical trial of vandetanib was initiated but withdrawn because of myelosuppression. She deferred any further treatment and was alive with few symptoms despite persistent disease 1.5 years after initial diagnosis. Physicians should consider the diagnosis of invasive thyroid carcinoma in a dysphonic patient with an infiltrative endolaryngeal process despite intact vocal fold mobility.