LAUSR

FIGURE1. A, Axial plane postcontrast CT image shows a cysticmasswithin the pancreatic tail (thick arrow) and associating subcapsular large collection with heterogenous content (star) suggestive of the presence of blood elements. B, A slightly cranial slice of the same CT study shows a nodular, solid-appearing lesion within the cavity wall (arrow). Subcapsular splenic collection is again noted (star). C, Coronal plane T2-weightedMR image clearly delineates the cystic mass (arrows) arising from the pancreatic tail (arrowheads). D, Postcontrast axial plane T1-weighted MR image shows no apparent mural enhancement within the cyst (star). This finding was found to be more suggestive of a retracted mural clot over a neoplastic nodule. E, Gross surgical specimen demonstrates a hemorrhagic cystic lesion measuring 12 4 3 cm (arrowheads). The cyst had irregular borders and was located mainly between the pancreatic tail (curved arrows) and the spleen (arrows). F, Microscopic examination revealed glandular structures (stars) scattered within the background endometrial stroma (arrowheads). Adjacent glandular pancreatic tissue was also observed (thick arrows). G, Immunohistochemical studies showed staining of estrogen receptors within the stromal cells. P ancreatic involvement in patients with endometriosis is extremely rare, with around 10 reported cases in the medical literature. Preoperative diagnosis of pancreatic endometriomas (PEs) may be extremely difficult without histopathological confirmation. The imaging characteristics of PE are not very well defined. The rupture of an endometrioma is also a rare clinical situation. The estimated incidence of spontaneous rupture among women, with known endometriomas, of childbearing age is around 3%. To the best of our knowledge, imaging findings of a spontaneously rupturing PE have not been described in the literature.