Opportunistic Disease or Metastatic Lesions: A Rare Finding in a Patient with Bladder Cancer.

A 66-year-old male with a history of human immunodeficiency virus infection and metastatic bladder cancer presented to our hospital for a further workup of a focal seizure involving the patients left upper extremity. The patient was undergoing active chemotherapy at the time of admission and had a CD4 count of 111. Magnetic resonance imaging of the brain revealed multiple ring-enhancing lesions in the right frontal lobe associated with vasogenic edema, and mass effect at the right frontal horn of the lateral ventricles. As the imaging was not consistent with typical metastatic disease of the bladder, further testing was performed. A lumbar puncture was performed to assist in differentiating between malignant and infectious causes in the setting of a low CD4 count. The cerebral spinal fluid was sterile and no malignant cells were identified. Protein and glucose levels of the cerebral spinal fluid were within normal range. To confirm the presence of metastatic disease, a brain biopsy was performed and found to be consistent with metastatic carcinoma with a bladder primary. The patient subsequently underwent radiation therapy to the site of the brain metastasis.