A case of malignant pheochromocy

抄録

Background: Malignant pheochromocytoma cytology is reported in a very rare case showing morphologic alteration and increased proliferation following onset.
Case: A 59-year-old man diagnosed with pheochromocytoma eventually died of repeated tumor recurrence over a period of 34 years. Histologically, tumor cells became small and uniform with decreasing granular cytoplasm and higher indices of cell proliferation and death one year prior to the patient's death. Stump specimens from a tumor at autopsy showed small tumor cells with prominent nucleoli and faintly granular cytoplasm. Some cells exhibited nuclear inclusion. Anisonucleosis was not conspicuous and occasional mitotic figures were seen.
Conclusion: Cytological findings in our case are representative of malignant pheochromocytoma with high growth. Occasional mitoses and the small, uniform appearance of tumor cells may help in cytologically diagnosing malignancy in pheochromocytoma.