Multiple Cutaneous Metastases on 99mTC-HYNIC-TOC Scan in a Rare Case of Malignant Laryngeal Paraganglioma.

Laryngeal paraganglioma is a rare neuroendocrine tumor arising from neural crest cells of larynx, contributing to 0.6% of the laryngeal tumors. Patients usually present with compressive symptoms such as hoarseness of voice. These tumors express somatostatin receptors, which can be imaged with radioligands such as 99mTc labeled hydrazinonicotinyl-Tyr3-octreotide (HYNIC-TOC). The percentage of malignant transformation in laryngeal paraganglioma is 2%, and they usually metastasize to lymph nodes, bone, and liver. Here, we report a 99mTc HYNIC-TOC scan of a 55-year-old male patient with recurrent laryngeal paraganglioma, who presented with painful multiple metastatic cutaneous nodules.