Spontaneous regression of pineal lesions: ghost tumor or pineal apoplexy?

Pineal apoplexy (either hemorrhagic or ischemic) may complicate the course of a tumor at this site. This event is usually characterized by an acute clinical onset and requires emergency surgical management while the regression of the lesion is a much rarer outcome. MATERIAL AND METHODS: Three cases of pineal vanishing tumors in the pediatric population are reported and the pertinent literature is reviewed. RESULTS: In one case radiological findings were consistent with a diagnosis of pineal cyst, which became symptomatic after a spontaneous hemorrhage. This event may also explain its regression after the treatment of associated hydrocephalus. In the remaining two cases, neuroimaging examinations disclosed a solid tumor. One of them regressed after a surgical biopsy, probably because of an ischemic evolution, while the last one disappeared without any medical or surgical manipulation. Neither hemorrhage nor ischemia were noticed, thus the mechanism of regression remains controversial. CONCLUSIONS: Vanishing tumors of the pineal region may occur in different circumstances, resulting from absence of any medical and surgical action to minor manipulation of the tumor to obtain a biopsy. This variety may reflect different underlying mechanisms, leading to hemorrhagic or ischemic change of the tumor and its subsequent regression, although radiological imaging may fail to document hemorrhage or ischemia.