Case of optic nerve involvement in metastasis of a gastrointestinal stromal tumor

Background: The gastrointestinal stromal tumor (GIST) belongs to the leiomyosarcoma or leiomyoma group, and metastasis of leiomyosarcoma to the orbit is extremely rare. The most common sign of the metastasis of leiomyosarcoma to the orbit is proptosis; the primary lesion is usually found in skin or soft tissue. Case: A 60-year-old man, who had a history of multiple metastases of GIST, suffered sudden unilateral blindness. Observations: His history and computed tomographic scans suggested that the lesion was a metastasis of GIST to the cavernous sinus around the root of the optic nerve. Conclusion: To the best of our knowledge, this is the first case of metastasis of GIST to the orbit. (C) Japanese Ophthalmological Society 2004.