Psammoma bodies in endometriosis: clinical, cytological, and physiopathological implications.

This, to the best of our knowledge, is the first report of the cytological observation of psammoma bodies in an endometrioma. Psammoma bodies are laminated, calcified spherites, commonly associated with meningiomas, ovarian serous cystadenocarcinomas, and papillary carcinoma of the thyroid. Many other pathologic processes can produce dystrophic calcification in the form of psammoma bodies. The physiopathological theories of the origin of dystrophic calcification and psammoma bodies will be discussed. The most promising theory implicates matrix vesicles as the nidus for calcification.