CNS Masson Tumors: Frequent Association With Therapeutic Radiation.
Masson tumor (MT, papillary endothelial hyperplasia) is an exaggerated form of thrombus reorganization rarely occurring in the central nervous system (CNS), where it presents as a mass or hemorrhage in parenchyma, meninges, or venous sinuses. MT is subclassified as type 1 arising within a histologically normal vessel, type 2 associated with a ruptured vascular malformation, and extravascular. Limited reports of CNS MT after radiosurgery, or especially external radiation therapy, have emerged. We searched our databases for cases reported from 2008 to present. Nine cases were identified, 6 of which were associated with receipt of therapeutic radiation for known lesions, with intervals of 1 to 25+ years to MT development (4 neoplasms=external beam radiation; 1 neoplasm=external beam radiation+radiosurgery, 1 arteriovenous malformation=radiosurgery). MTs were coassociated with radiation-induced vascular malformations (1 cavernoma-like, 1 massive) only in 2 of 6 irradiated patients, whereas the other 4 had MTs only. The 3 MTs in nonirradiated patients were extravascular, with 1 spontaneously developing in a hemangioblastoma. Seven of 9 MTs were intracerebral, 1 was within the spinal cord, and 1 was subdural. Papillary MT architecture was best appreciated by CD31 or CD34 immunohistochemistry, although ERG verified the endothelial monolayer population. Most CNS MTs at our institution have arisen in patients who have received therapeutic cranial radiation, many of whom received only external beam radiation. Although MTs could conceivably represent early, severe phases in radiation-induced cavernoma development, most were not found coassociated with the latter. This study further extends our knowledge of types of radiation-induced CNS vascular abnormalities.
Departments of *Pathology †Neurology ‡Neurosurgery, The University of Colorado School of Medicine, Aurora, CO.
Patrick
P
Mann
Bette K
BK
Kleinschmidt-DeMasters
D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis; D016543:Central Nervous System Neoplasms / Q000737:chemistry / Q000209:etiology* / Q000401:mortality / Q000473:pathology / Q000628:therapy; D002675:Child, Preschool; D016371:Cranial Irradiation / Q000009:adverse effects* / Q000401:mortality; D042783:Endothelial Cells / Q000737:chemistry / Q000473:pathology / Q000528:radiation effects*; D005260:Female; D006801:Humans; D006965:Hyperplasia; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009381:Neoplasms, Radiation-Induced / Q000737:chemistry / Q000209:etiology* / Q000401:mortality / Q000473:pathology / Q000628:therapy; D012307:Risk Factors; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D015534:Trans-Activators / Q000032:analysis; D000071230:Transcriptional Regulator ERG; D019043:Vascular Neoplasms / Q000737:chemistry / Q000209:etiology* / Q000401:mortality / Q000473:pathology / Q000628:therapy
D014408:Biomarkers, Tumor; C072312:ERG protein, human; D015534:Trans-Activators; D000071230:Transcriptional Regulator ERG