Brain Pathology Case of the Month - January 2012

Contributed by Maysa Al-Hussaini, MD1, Izzeddin Bakri, MD2, Maisa Swaidan3, MD, Usama Jumaily, MD4, Najyah Abuirmeileh, MD4
1Department of Pathology and laboratory Medicine, 3 Department of Radiology
4 Department of Pediatrics, King Hussein Cancer Center, Amman, Jordan.
2Department of Pathology, Makassed Hospital, Jerusalem.


A 4 month old male infant with an uneventful antenatal and natal history, presented with persistent vomiting and recurrent right-sided focal seizures of one month duration. He was seen by a pediatrician and found to have wide bulging fontanels and a large head circumference (46 cm, above 90 percentile), with limited movement in the right upper limb. Brain US showed a left sided brain mass. Brain MRI was requested and showed a large mainly cystic septated mass, with a thin non-enhancing wall and a relatively large vividly enhancing mural nodule. The mass involved the left parieto-occipital lobes and was deeply located in close relation to the left lateral ventricular trigone. Extensive associated white matter edema was noted. He underwent emergency craniotomy and complete resection of the tumor was attempted. Post operative brain MRI showed a large cystic lesion measuring about 4.7x5 cm at the site of surgery with no evidence of enhancement. He was seizure free with no weakness post craniotomy.


Pre operative brain MRI of axial T1 weighted image (WI) showed a large mainly cystic mass in the left parieto-occipital lobes with marked surrounding white matter edema (Figure-1). There was a hyperintense solid nodule at the medial part of the mass in close relation to the left lateral ventricular trigone. Its relation to the choroid plexus could not be assessed. The cystic part of the mass was septated. The solid nodule showed vivid enhancement after contrast administration (Figure-2) while the walls of the cystic component did not. Axial T2 WI of the cystic part of the mass contained CSF intensity fluid while the solid part of the mass was hypointense (Figure-3).


Sections examined from the pathology material revealed a papillary tumor (Figure-4). The papillae were lined by a single layer of cuboidal to columnar cells (Figure-5) with acidophilic cytoplasm, and occasional cells displaying clear cytoplasm. The nuclei showed minimal atypia (Figure-5). Mitotic activity was brisk and several high power fields contained more than one mitotic figure (Figure-6). Calcifications were identified in the cores of several papillae (Figure-7). In a single focus; invasion into the brain parenchyma (Figure-8) was identified with surrounding reactive astrocytes (Figure-9). Adjacent normal choroid plexus was seen (Figure-10). S-00 protein was negative in the tumor cells, but positive in the normal choroid plexus (Figure-11). Transthyretin was positive in the tumor cells (Figure-12). MIB-1 immunostain revealed high proliferative index (Figure-13).


International Society of Neuropathology