Dopamine-Secreting Carotid Body Paraganglioma in a Patient With SDHB Mutation

Background/objective: Exclusively dopamine-secreting paragangliomas (PGLs) are rare, and the majority of head and neck PGLs are nonsecretory. Here, we describe a patient with succinate dehydrogenase subunit B (SDHB) mutation and a dopamine-secreting carotid body PGL to highlight the potential importance of screening for dopamine excess in patients with suspected PGL.

Case report: We report a 34-year-old patient who presented with cranial nerve palsy and was found to have a cerebellopontine PGL. Biochemical testing demonstrated increased circulating dopamine levels with normal levels of other catecholamines. Dopamine excess improved with resection of the PGL, and subsequent genetic testing revealed an SDHB mutation.

Discussion: Secretory head and neck PGLs and exclusively dopamine-secreting PGLs are both uncommon and rarely present together, although PGLs in patients with SDHB mutations often do produce dopamine. Although current guidelines do not recommend routine evaluation of the dopamine levels in patients at risk for PGL, dopamine-secreting PGLs are frequently locally invasive or metastatic.

Conclusion: Screening for dopamine excess in patients with a predisposition to PGL or with suspected PGL may aid in diagnosis and as a marker of successful treatment.