78-year-old woman with a history of breast cancer and multiple basal and squamous cell skin cancers presented with intractable right facial pain. She initially developed diplopia and headaches two years prior. Brain MRI, CSF, and ophthalmology evaluation were unrevealing. PET scan was negative in the brain but showed mild chest adenopathy concerning for sarcoidosis. Empiric treatment with steroids yielded no improvement. Repeat MRI revealed a subtle enhancing soft tissue mass in the right cavernous sinus but biopsy was unremarkable. One year later, she began experiencing right eye pain and facial numbness. Orbital MRI demonstrated significant enlargement of the cavernous sinus mass with new involvement of the right V2 and V3 trigeminal branches. A second biopsy revealed non-caseating granulomas. For presumed neurosarcoidosis, she tried prednisone, infliximab, and cyclophosphamide but subsequent MRI showed disease progression. Her facial pain and headaches worsened and she received palliative radiotherapy without relief. When she failed a combination of carbamazepine, gabapentin, methadone, hydrocodone-acetaminophen, prednisone, and methylphenidate, an intrathecal narcotic pump was recommended. She presented to us for a second opinion.
Exam was notable for severe right-sided trigeminal sensory neuropathy involving all divisions. Extensive laboratory workup only revealed elevated inflammatory markers. MRI showed an infiltrating enhancing process in V3 segment and PET scan demonstrated associated hypermetabolic activity. Differential diagnosis included malignancy or autoimmune inflammation. Ultimately, trigeminal nerve biopsy confirmed intraneural dissemination of squamous cell carcinoma, likely of facial origin. Radiotherapy was discussed and the patient elected to seek therapy closer to home.