Lung cancer presenting with trigeminal neuropathy.

The purpose of this case report is to describe MR imaging and CT findings of a patient in whom the first clinical and neuroradiological manifestation of a metastatic lung adenocarcinoma was unilateral trigeminal neuropathy caused by a presumed metastasis involving cisternal and Meckel's cave segments of ipsilateral trigeminal nerve. MR imaging and CT scan differential diagnosis of expansive lesions of the intracranial trigeminal nerve must include metastases. Physicians and neuroradiologists must be aware of metastases as an uncommon cause of trigeminal neuropathy, even as the presenting condition of cancer.