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Show J. Clin. Neuro-opththalmol. 4: 133-136, 1984. Spontaneous Reduction of Growth Rate of a Large Intracranial Meningioma Case Report ROBERT F. SAUL, M.D. ARTHUR B. KING, M.D. Abstract A relatively young patient with a large intracranial meningioma producing a paucity of neurological signs and symptoms showed no progression of symptomatology over 14 years. This may represent a spontaneous growth arrest in an otherwise early expected fatal outcome. The location of the tumor with its benign course producing no demonstrable increase in visual loss over 14 years in such a young patient is quite unusual. Introduction Classically, meningiomas are benign, encapsulated, fibrous tumors arising from the arachnoid. They compromise approximately 15% of all intracranial neoplasms. They are often well-circumscribed and produce clinical symptoms by compressing underlying neural and vascular structures. These tumors are usually encapsulated, but a moderate percentage do infiltrate adjacent tissues and they have been known to metastasize. Growth characteristics usually differ according to the histological type, but this is not invariably so. It is well-documented that meningiomas may reach enormous size, growing slowly, and frequently producing minimal symptoms. 1-3 We have encountered such a case that we believe may represent either a spontaneous growth arrest or a marked reduction of growth rate. Because of the patient's youth and the size and location of the tumor, we predicted a fatal outcome. To our surprise, this did not occur. Case History A 34-year-old male factory worker was first seen in July 1975 for evaluation of a long-stand- From the Department of Neurology (RFS), Geisinger Medical Center, Danville, Pennsylvania; and the Section of Neurosurgery (ABK), Guthrie Clinic, Sayre, Pennsylvania. June 1984 ing, painless loss of vision in the right eye. He was 27 years old at that time. The blindness in the right eye had been discovered on a routine preemployment general physical examination 7 years earlier. He had not noticed visual loss in the left eye. Examination in 1975 showed no light perception (NLP) in the right eye and 20/25 acuity in the left eye. Formal visual fields of the left eye were normal on two occasions. The right optic nerve showed advanced optic atrophy, while the left eye showed some early disc pallor. Ocular motility, facial sensation, and olfaction were normal. A huge, calcified, parasellar. olfactory groove mass was found extending superiorly into the anterior fossa and inferiorly into the adjacent paranasal sinuses. A biopsy of the tumor eroding into the sinus was performed. This was compatible with a psammomatous meningioma (Fig. 1). A bifrontal craniotomy was performed, and a moderate amount of tumor was excavated from within a hard capsule. The right optic nerve was totally surrounded by a tumor and the left would need to be sacrificed for a total removal. It was decided not to procede further. The wound was closed, and a large amount of tumor was left behind. The patient did well postoperatively, and was lost to follow-up until March 1982. He returned for a disability examination. He denied any further visual loss in the left eye. Examination still showed the visual acuity to be NLP in the right eye and 20/25 in the left eye. His visual field in the left eye was again normal as was his color vision. The optic disc remained essentially the same as described previously with only minimal pallor on the left. The ocular motility was normal. but his sense of smell was now bilaterally diminished (right olfactory nerve was identified during surgery according to the operative report). A visual-evoked potential showed a minimal conduction delay to the pattern reversal stimulation in the left eye. The right eye was not done. Computed tomography (CT) of the head showed a large, calcified mass as described previously Intracranial Meningioma Figure 1. Meningioma with psammoma body formation. (Figs. 2a and 2b). Roentgenograms of the skull from 1975 showed no gross change in the external bulk of the mass as compared with the recently done CT scan (Fig. 3). No further workup was done and the patient was discharged. Discussion The patient's tumor represents a number of intriguing features. First, he was only 20 years old when the blind right eye was discovered, probably dating the onset of the visual loss to an even earlier age. In a review of 2,620 tumors in children, Mendiratta et a1. found only 38 cases of meningiomas (1.5%).01 Second, he had a psammomatous histological type which is also uncommon at his age. In Deen's series of 51 meningiomas occurring between the ages of 7 and 20! only five were of the psammomatous type. o Third, the enormous tumor surrounded an area where neurological and endocrine dysfunction is usually noted in much smaller lesions and did not progress in 14 years of our known observation. It is not uncommon to find a minimally symptomatic meningioma of considerable size at autopsy. Wood found 100 meningiomas in 300 pa- 134 tients with asymptomatic brain tumors.6 The largest was 7.8 cm in diameter, but 61% were 1 cm or less. Interestingly, 19.5% of all of meningiomas were in the sella-rolfactory region. A spontaneous growth arrest of meningiomas is rarely discussed by those describing intracranial neoplasms. It is often noted that psammoma body formation is typical of the more slow-growing meningiomas and may represent a stage of regressive process. 7 Conversely, Skullerud and Loken felt that high cellularity was found more frequently among recurrent tumors.s Our patient's tumor did not demonstrate this latter quality. However, we have seen highly malignant meningiomas whose cell size and patterns were no different from those of very lethargic growth. This case illustrates a benign course in what one could have thought would be a fatal outcome. It demonstrates that a biopsy may carry some predictive value in an otherwise unresectable meningioma. The presence of psammoma bodies, the lack of cellularity, and the long history, seem to favor a better prognosis. This case follows these criteria, but leaves one wondering why there was preservation of vision and cranial nerve function. When the structures were totally surrounded by Journal of Clinical Neuro-ophthalmology June 1984 (6) Figures 2a and 2b. Computerized tomography showing size and extent of tumor in 1982. Saul. King 135 Intracranial Meningioma Figure 3. Lateral skull x-ray in 1975. showing postoperative appearance of the tumor. tumor, one can only speculate that the blood supply to the structures remained intact, and that local pressure was at a minimum. It is also odd that so much tumor about the hypothalamus, pituitary, and pituitary stalk did not produce any observable endocrine dysfunction. References 1. Cech, D.A., Leavens, M.E., and Larson, D.L.: Giant intracranial and extracranial meningiomas: Case report and review of the literature. Neurosurgery 11: 694-697, 1982. 2. Cushing, H., and Eisenhardt, L.: Meningiomas: Their Classifica!ioll, Regional Behavior, Life History, Qlld Surgical Results. Charles C Thomas, Springfield, Illinois, 1938. 3 Hirsh, L.F., and Mancall, E.L.: Giant meningiomas of the posterior fossa. rA.M.A. 240: 626-627, 1978. 4. Mendiratta, E.5., Rosenblum, J.A, and Strobos, R.J.: Congenital meningioma. Neurology 17: 914918,1967. 5. Deen, H.G., Jr., Scheithauer, B.W., and Ebersold, M.J.: Clinical and pathological study of meningiomas of the first two decades of life. J. Neurosurg. 56: 317-322,1982. 6. Wood, M.W., White, R.J., and Kernohan, ].W.: One hundred intracranial meningiomas found incidentally at necropsy. J. Neuropathol. Exp. Neurol. 16: 337-340,1957. 7. Goldensohn, E.F., and Appel, S.H. (Eds.): Scielltific Approaches to Clillical Neurology. Lea and Febiger, Philadelphia, 1978, p. 958. 8. Skullerud, K., and Loken, AC.: The prognosis in meningiomas. Acta Neuropathol. (Berl.) 29: 337344,1974. Write for reprillts to: Robert F. Saul, M.D., Department of Neurology, Geisinger Medical Center, Danville, Pennsylvania 17822. Journal of Clinical Neuro-ophthalmology |