Rapidly progressive bilateral ophthalmoplegia and enlarging sellar mass caused by amelanotic melanoma.

A 63-year-old woman with diplopia and bilateral ptosis underwent brain MRI that showed a pituitary mass with signal characteristics suggestive of adenoma. Within one week she had developed nearly complete bilateral ophthalmoplegia. A repeat MRI showed extension of the mass into both cavernous sinuses. Hypophysectomy disclosed an amelanotic melanoma. Extensive search for a primary source was unsuccessful. Despite local radiation treatment, the tumor continued to grow and the patient became blind and died within several months of diagnosis. There are seven reported cases of melanoma arising primarily in the sella turcica. Two cases of metastatic melanoma to the cavernous sinuses have been reported. Amelanotic melanoma has not been reported as a cause of cavernous sinus syndrome.