We report two cases of paraganglioma originating in the paraseller region (case 1) and in the urinary bladder (case 2). The subject in case 1 was a 59-year-old man who was admitted into the hospital with dizziness, muscular weakness of the left extremities and cold sweating. Magnetic resonance imaging (MRI) revealed a tumor in the parasellar region. The subject in case 2 was a 39-year-old man who was hospitalized because he had a sense of residual urine. Computed tomography and MRI showed a

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... of tumor tissue in the posterior region of the left ureteric orifice of the bladder. Imprint cytology of both tumors showed isolated, loosely attached sheet-like cells with abundant cytoplasm and round or oval nuclei. Histologically, both tumors consisted of round or polygonal cells in small packets separated by vascular fibrous septa. Immunohistochemically, both tumor cells were positive for NSE, S-100 protein, chromogranin A, and synaptophysin. Electron microscopic examination revealed neurosectretory granules in the cytoplasm of tumor cells in either of these two cases.