Cavernous malformations are vascular malformations that can occur anywhere in the central nervous system (CNS). Giant cavernous malformations (GCM) are extremely rare in adults, especially in the posterior fossa. Herein, we described a 48-year-old male who presented with vertigo and postural instability for three months. Neuroimaging revealed a 131.15 cm3 heterogeneous midline upper cerebellar lesion. After a suboccipital craniotomy, a gross total resection (GTR) was accomplished. Histopathologic examination revealed a huge cavernous malformation. Only 27 GCM adult cases were reported in the English-based literature. Only two patients had cerebellar lesions and, to the best of our knowledge, this is the first case of cerebellar vermis GCM. We concluded that cerebellar GCM (CGCM) in adults are exceedingly rare and indolent lesions. These lesions can radiologically and clinically mimic neoplastic lesions that have to be considered in the differential diagnosis. GTR is the mainstay of treatment and, whenever possible, should be attempted.
Keywords: Cavernous malformation; brain tumor; posterior cranial fossa.