Angiocentric Glioma: Is It Really WHO Grade I?
Kari K Hooper, Jailan M Osman, Siraj M El Jamal, Ali G Saad. Arkansas Children's Hospital, Little Rock
Background: Angiocentric glioma (AG) is a recently described brain tumor and is recognized by the 2007 WHO classification of central nervous system as a grade I tumor. AG is characterized by slow growth and typically presents with seizures in children and young adults. The cytogenesis remains unclear; however, ependymal and glioneuronal origins have been proposed.
Design: Three AGs are included in this study [two AGs were retreived from the files of the department of Pathology at Arkansas Children's Hospital (from 1995 and 1998, respectively) which were interpreted then as pilocytic astrocytoma]. A third case was received in 2009. Demographic and clinical findings were retrieved from medical records.
Results: Histologically, the tumors were characterized by diffuse growth and prominent perivascular tumor cell arrangements with features of astrocytic/ependymal differentiation. Rosenthal fibers and eosinophilic granular bodies were absent. Necrosis and vascular proliferation were not observed and mitoses were sparse or absent. On follow up (mean 31.3 months; range 14-49 months), one patient had 2 recurrences, another had 3 recurrences and one patient is still disease-free 14 months after surgery. The 1st recurrence occurred after a mean period of 10 months (range: 9-11 months) and the second recurrence occurred after a mean period of 19.5 months (range 19-20 months). The 3rd recurrence occurred 32 months after the first surgery. Histologic examination showed that recurrences were not accompanied by progression of tumor grade or MIB-1 labeling indices. A summary of the clinical and demographic findings is presented in Table 1.
|Case||Age (years)||Sex||Location||Clinical presentation||Follow-up||Ki 67 labeling index||Extent of surgery|
|1||6.7||M||Frontal||Seizures||2 recurrences at 11 and 19 months after 1st surgery, respectively||2, 2 and 3%, respectively||Total gross resection|
|2||10.3||M||Temporal||Seizures||3 recurrences at 9, 20 and 32 months after 1st surgery, respectively||1, 3, 2, and 5%, respectively||Total gross resection|
|3||13.9||F||Temporal||Seizures||Disease-free 14 months after surgery||2%||Total gross resection|