Cervicogenic headache arising from hidden metastasis to cervical lymph node adjacent to the superficial cervical plexus -A case report-.

The differential diagnosis of headache is often difficult because the symptom of headache is overlapping. Superficial cervical plexus block is useful in diagnosis and treatment of headache. Headache arising from the neck and radiating to the frontotemporal regions and possibly to the supraorbital region has been defined as cervicogenic headache. A positive response to anesthetic blocks is one of the diagnostic criteria of cervicogenic headache. We experienced a case of headache arising from direct lymph node metastasis of hepatocellular carcinoma adjacent to the superficial cervical plexus during treatment of cervicogenic headache under ultrasonographic guidance. Especially in patients with medical history of cancer, practitioners should consider the possibility of metastasis to cervical lymph nodes and using ultrasonography to evaluate the cervical area prior to the practice.