Giant fronto-spheno-orbitary juvenile psammomatoid ossifying fibroma: Case report and literature review.

Juvenile psammomatoid ossifying fibroma (JPOF) is an osteofibrous neoplasm that originates in the craniofacial skeleton typically during the first three decades of life. JPOFs usually involve the orbit, paranasal sinuses or the jaws. Extensive involvement of the anterior cranial base with compromised visual function is a rare phenomenon. In such clinical context, a definite diagnosis can only be made on the basis of histopathological findings, given the absence of pathognomonic radiological features. Despite being considered a benign entity, JPOFs present a locally aggressive behavior. Therefore, these neoplasms must be included in the differential diagnosis in every patient harboring a skull base osteofibrous lesion, and, once diagnosed, gross total surgical removal should be attempted. In this study, we present our experience in the diagnosis and treatment of a patient diagnosed with a giant JPOF involving the cranial base.

Rare association of secondary superficial siderosis caused by a fourth ventricle hemorrhagic ependymoma mimicking a cavernoma: Case report and literature review.

BACKGROUND: The association of a hemorrhagic tumor with secondary superficial siderosis (SS) is a relatively rare although well described phenomenon. CASE DESCRIPTION: We present the case report of a 35-year-old male with a history of drowsiness, hypoacusia, drop attacks, and multidirectional nystagmus during the last 2 months, who presented with acute obstructive hydrocephalus caused by a fourth ventricle mass displaying radiological signs of repeated intra and extratumoral hemorrhage with SS. He underwent gross surgical removal of the solid component of the tumor. Microscopic examination revealed an ependymoma with atypical features, including prominent angiomatous formations and internal chronic hemorrhages with hemosiderin deposits, resembling a cavernoma. The scarce tumoral component, which extended around these cavernous vessels, lacked the gross typical features of fibrillary stroma or perivascular pseudorosettes. CONCLUSION: To our knowledge, including the present case, there are 45 published reports of tumors associating secondary SS. Besides ependymoma, no other hemorrhagic lesion, tumoral or vascular, has been previously published associating a fourth ventricle location with secondary SS. The present case represents the fifth with this finding, and we strongly suggest ependymoma as a presumptive diagnosis when this rare association is encountered. In addition, this appears to be the first case reported in the scientific literature of a hemorrhagic fourth ventricle ependymoma mimicking both, radiologically and histologically, a cavernous malformation.