title: Edema is a precursor to central nervous system peritumoral cyst formation.
abstract: Despite the common occurrence and frequent clinical effects of peritumoral cysts in the central nervous system (CNS), the mechanism underlying their development and evolution is not understood. Because they commonly produce peritumoral cysts and because serial magnetic resonance imaging (MRI) is obtained in von Hippel-Lindau disease patients, hemangioblastomas provide an opportunity to examine the pathophysiology of CNS peritumoral cyst formation. Serial MRI was correlated with the clinical findings in 16 von Hippel-Lindau disease patients with 22 CNS hemangioblastomas (11 spinal cord; 11 cerebellar) that were associated with the appearance and evolution of peritumoral cysts. Hemangioblastoma-associated cyst wall histomorphological analysis was performed on postmortem tissues from three von Hippel-Lindau disease patients (not in the clinical series). Comparative proteomic profiling was performed on peritumoral cyst fluid and serum. Vascular endothelial growth factor levels were determined in peritumoral cysts. MRI clearly showed peritumoral edema that developed and slowly and progressively evolved into enlarging hemangioblastoma-associated cysts in all tumors (mean follow-up, 130 +/- 38 months; mean +/- standard deviation). Postcontrast MRI demonstrated convective leakage of gadolinium into cysts. Mean time required for edema to evolve into a cyst was 36 +/- 23 months (range, 8-72 months). Thirteen (59%) hemangioblastoma-cysts became symptomatic (mean time to symptom formation after cyst development, 35 +/- 32 months; range, 3-102 months) and required resection. Protein profiles of cyst fluid and serum were similar. Mean cyst fluid vascular endothelial growth factor concentration was 1.5 ng/ml (range, 0-5.4 ng/ml). Histology of the cyst walls was consistent with reactive gliosis. CNS peritumoral cyst formation is initiated by increased tumor vascular permeability, increased interstitial pressure in the tumor, and plasma extravasation with convective distribution into the surrounding tissue. When the delivery of plasma from the tumor exceeds the capacity of the surrounding tissue to absorb the extravasated fluid, edema (with its associated increased interstitial pressure) and subsequent cyst formation occur.
authors.affiliation: Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA. lonserr@ninds.nih.gov
authors.forename: Russell R
authors.initials: RR
authors.lastname: Lonser
authors.forename: Alexander O
authors.initials: AO
authors.lastname: Vortmeyer
authors.forename: John A
authors.initials: JA
authors.lastname: Butman
authors.forename: Sven
authors.initials: S
authors.lastname: Glasker
authors.forename: Michael A
authors.initials: MA
authors.lastname: Finn
authors.forename: Joshua M
authors.initials: JM
authors.lastname: Ammerman
authors.forename: Marsha J
authors.initials: MJ
authors.lastname: Merrill
authors.forename: Nancy A
authors.initials: NA
authors.lastname: Edwards
authors.forename: Zhengping
authors.initials: Z
authors.lastname: Zhuang
authors.forename: Edward H
authors.initials: EH
authors.lastname: Oldfield
mesh_terms: D000328:Adult; D001344:Autopsy / Q000379:methods; D001932:Brain Neoplasms / Q000097:blood / Q000134:cerebrospinal fluid / Q000473:pathology* / Q000503:physiopathology; D020863:Central Nervous System Cysts / Q000097:blood / Q000134:cerebrospinal fluid / Q000473:pathology* / Q000503:physiopathology; D004487:Edema / Q000150:complications / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D013997:Time Factors; D042461:Vascular Endothelial Growth Factor A / Q000097:blood / Q000134:cerebrospinal fluid
chemical_list: D042461:Vascular Endothelial Growth Factor A