Extracalvarial Meningioma Case Report*

GEORGE J. SIEGEL,t M.D., AND PAUL J. ANDERSON,M.D. Departments of Neuropathology and Neurology, Mount Sinai Itospital, New York, N. Y.

The case described below prompted a search underlying was grossly normal, complete for previous reports of meningioma with no histologic examinations of the full thickness of gross evidence of intracranial or intraspinal bone and aponeurosis were not provided. This involvement. Excluded from consideration were entire group has been reviewed previously. 4 those primary intracranial tumors that directly All of the cases in these $ groups had in com- invaded extracranial structures and those re- mon the presence of a meningioma on the ex- lated to the orbits and cranial nerve foramina. ternal surface of the or in the skin The reports of extracalvarial meningiomas with no gross intracranial component. When were divided into 3 general groups. The first microscopic examinations of the adjacent cal- consisted of 5 cases of meningioma occurring varia were provided, however, the underlying within the maxillary e'14 and frontal sinuses. 1~ bone was found to be invaded by neoplasm. Craniotomies were performed and the dura and The present case is that of an additional inner tables examined in only ~ of this group 6a~ apparently extracalvarial meningioma (similar and both were found to be normal. In one of to those described in the second group), without these, a meningioma in the frontal sinus, the gross dural attachment, but with histologic adjacent was examined microscopi- evidence of transosseous spread and dural cally and found to be invaded by neoplasm. 1~ In invasion. the other, a meningioma in the maxillary an- trum, fragments of the sphenoid wings were Case Report histologically normal. 6 In 3 additional cases, not J.A., a 53-year-old man, was admitted to the neuro- considered here, the tumor was more extensive, surgical service on April 22, 1965, because of a slowly involving the orbits, as well as sphcnoid, eth- growing, hard, fixed mass present in the mid-posterior moid, and maxillary sinuses. 3,s,13 frontal region for 6 months. Neurological examination and electroencephalogram The second group included a total of 7 menin- were normal. roentgenograms showed circum- giomas adherent to the outer surface of the scribed hyperostosis of the inner and outer tables in frontal or temporal ) ,1~I2,15,17 In the 5 the region of the bregma and an adjacent extraeranial cases in which craniotomies were performed, 5,1~ soft tissue mass. Carotid arteriography demonstrated 12.15 no intracranial tumor was found, although a branch of the middle meningeal artery entering the the dura was thickened in ~ instances. 15 With extraeranial mass (Fig. 1). the exception of one case in which the subjacent At operation, a well circumscribed tumor was found bone was simply described as "destroyed, ''I~ attached to the outer table of the calvaria in the region histologic examination demonstrated osseous of the bregma. The scalp, including the skin, subcutan- eous tissue, galea aponeurotica, and subaponeurotic infiltration by neoplasm. In 2 cases the dura connective tissue, were normal. The tumor and the sur- also was infiltrated. 15 Skull roentgenograms rounding bone were completely excised. The underlying were normal in 1 case 5 and showed hyperostosis dura was incised and found to be normal on both sur- in the remaining 4. X-rays were reported as faces. normal in the 2 cases in which craniotomy was The postoperative course was uneventful and neuro- not performed, u'17 logical examination ~ months later was normal. The third group comprised 6 cases of menin- Pathology. The specimen consisted of a hemisphere- giomas in the scalp without attachment to the shaped tumor fixed to the external surface of a disc of bone 1,4,9 and 1 case with 3 separate cutaneous the calvaria (Fig. 2). It was encapsulated by a thin but distinct connective tissue membrane that was con- meningiomas in the dorsal paraspinal region? 6 tiguous with the pericranium or external periostcum. The tumors in the scalp were near the midline An x-ray of the specimen showed the bregma underlying in the frontal or occipital regions. Although the the approximate center of the neoplasm (Fig. 3). The central portion of the tumor was densely adherent to Received for publication July 10, 1965. the markedly thickened lamina externa of bone at this * Supported by Grant No. NB 05~1 from the United site, while its periphery was easily stripped from the States Public Health Service. bone. The lamina interna was uuremarkable and thin Trainee, U.S. Public Health Service Training Grant strands of dura were adherent to its surface. The tumor No. NB-507~. was gray, uniformly solid, firm and resilient, and mea- 83 FIG. 1. Right carotid arteriogram showing a branch of the middle meningeal artery entering the extracranial soft tissue mass (arrow) in the region of the hyperostotic bregma.

FIG, 2. Cross-section of the surgical specimen showing the tumor situated on the outer surface of the hyperostotic calvaria.