The present report describes a case of a proliferative lesion developed in a struma ovarii of a 26-year-old woman who presented with asymptomatic bilateral mature ovarian teratomas. The tumor immunohistochemically and ultrastructurally proved to be an oxyphilic follicular thyroid tumor. Although it showed some histologic features which could raise a suspicion of malignancy (solid, trabecular pattern and nuclear pleomorphism), no unequivocable signs of aggressive behaviour (high mitotic activity and vascular invasion) were evident. The patient was alive and well 1 year after a bilateral subtotal ovariectomy.
CarcangiuM.L., BianchiS., SavinoD., VoynickJ.M., RosaiJ., Follicular Hurtle cell tumours of the thyroid gland. Cancer, 68: 1944–1953; 1991.
2.
DevaneyK., ShyderR., NorrisHJ., TavassoliF.A.: Proliferative and histologically malignant struma ovarii: a clinicopatho-logical study of 54 cases. Int. J. Gynecol. Pathol., 12: 333–343; 1993.
