Primary extracranial meningiomas are rare neoplasms, frequently misdiagnosed, resulting in inappropriate clinical management. To date, a large clinicopathologic study has not been reported. One hundred and forty-six cases diagnosed between 1970 and 1999 were retrieved from the files of the Armed Forces Institute of Pathology. Histologic features were reviewed, immunohistochemistry analysis was performed (n = 85), and patient follow-up was obtained (n = 110). The patients included 74 (50.7%) females and 72 (49.3%) males. Tumors of the skin were much more common in males than females (1.7:1). There was an overall mean age at presentation of 42.4 years, with a range of 0.3–88 years. The overall mean age at presentation was significantly younger for skin primaries (36.2 years) than for ear (50.1 years) and nasal cavity (47.1 years) primaries. Symptoms were in general non-specific and reflected the anatomic site of involvement, affecting the following areas in order of frequency: scalp skin (40.4%), ear and temporal bone (26%), and sinonasal tract (24%). The tumors ranged in size from 0.5 up to 8 cm, with a mean size of 2.3 cm. Histologically, the majority of tumors were meningothelial (77.4%), followed by atypical (7.5%), psammomatous (4.1%) and anaplastic (2.7%). Psammoma bodies were present in 45 tumors (30.8%), and bone invasion in 31 (21.2%) of tumors. The vast majority were WHO Grade I tumors (87.7%), followed by Grade II (9.6%) and Grade III (2.7%) tumors. Immunohistochemically, the tumor cells labeled for EMA (76%; 61/80), S-100 protein (19%; 15/78), CK 7 (22%; 12/55), and while there was ki-67 labeling in 27% (21/78), <3% of cells were positive. The differential diagnosis included a number of mesenchymal and epithelial tumors (paraganglioma, schwannoma, carcinoma, melanoma, neuroendocrine adenoma of the middle ear), depending on the anatomic site of involvement. Treatment and follow-up was available in 110 patients: Biopsy, local excision, or wide excision was employed. Follow-up time ranged from 1 month to 32 years, with an average of 14.5 years. Recurrences were noted in 26 (23.6%) patients, who were further managed by additional surgery. At last follow-up, recurrent disease was persistent in 15 patients (mean, 7.7 years): 13 patients were dead (died with disease) and two were alive; the remaining patients were disease free (alive 60, mean 19.0 years, dead 35, mean 9.6 years). There is no statistically significant difference in 5-year survival rates by site: ear and temporal bone: 83.3%; nasal cavity: 81.8%; scalp skin: 78.5%; other sites: 65.5% (P = 0.155). Meningiomas can present in a wide variety of sites, especially within the head and neck region. They behave as slow-growing neoplasms with a good prognosis, with longest survival associated with younger age, and complete resection. Awareness of this diagnosis in an unexpected location will help to avoid potential difficulties associated with the diagnosis and management of these tumors.

"Primary" ear and temporal bone meningiomas are tumors that are frequently misdiagnosed and unrecognized, resulting in inappropriate clinical management. To date, a large clinicopathologic study of meningiomas in this anatomic site has not been reported. Thirty-six cases of ear and temporal bone meningiomas diagnosed between 1970 and 1996 were retrieved from our files. Histologic features were reviewed, immunohistochemical analysis was performed (n ‫؍‬ 19), and patient follow-up was obtained (n ‫؍‬ 35). The patients included 24 females and 12 males, aged 10 -80 years (mean, 49.6 years), with female patients presenting at an older age (mean, 52.0 years) than male patients (mean, 44.8 years). Patients presented clinically with hearing changes (n ‫؍‬ 20), otitis (n ‫؍‬ 7), pain (n ‫؍‬ 5), and/or dizziness/vertigo (n ‫؍‬ 3). Symptoms were present for an average of 24.6 months. The tumors affected the middle ear (n ‫؍‬ 25), external auditory canal (n ‫؍‬ 4), or a combination of temporal bone and middle ear (n ‫؍‬ 7). The tumors ranged in size from 0.5 to 4.5 cm in greatest dimension (mean, 1.2 cm). Radiographic studies demonstrated a central nervous system connection in 2 patients. Histologically, the tumors demonstrated features similar to those of intracranial meningiomas, including meningothelial (n ‫؍‬ 33), psammomatous (n ‫؍‬ 2), and atypical (n ‫؍‬ 1). An associated cholesteatoma was identified in 9 cases. Immunohistochemical studies confirmed the diagnosis of meningioma with positive reactions for epithelial membrane antigen (79%) and vimentin (100%). The differential diagnosis includes paraganglioma, schwannoma, carcinoma, melanoma, and middle ear adenoma. Surgical excision was used in all patients. Ten patients developed a recurrence from 5 months to 2 years later. Five patients died with recurrent disease (mean, 3.5 years), and the remaining 30 patients were alive (n ‫؍‬ 25, mean: 19.0 years) or had died (n ‫؍‬ 5, mean: 9.5 years) of unrelated causes without evidence of disease. We conclude that extracranial ear and temporal bone meningiomas are rare tumors histologically similar to their intracranial counterparts. They behave as slow-growing neoplasms with a good overall prognosis (raw 5-y survival, 83%). Extent of surgical excision is probably the most important factor in determining outlook because recurrences develop in 28% of cases.

Cree leukoencephalopathy is a rapidly fatal infantile autosomal recessive leukodystrophy of unknown cause observed in the native North American Cree and Chippewayan indigenous population. We found in the brain of affected individuals the typical foamy cells with the oligodendroglial phenotype described in central hypomyelination syndrome/vanishing white matter, a syndrome related to mutations in the genes encoding the five subunits of the eucaryotic translation initiation factor eIF2B. In three patients of two Cree families, we found a homozygous missense mutation resulting in a histidine substitution at arginine 195 of epsilon-eIF2B.

The effects of isolating the hippocampus from its neocortical inputs and outputs by damaging the deep layers of entorhinal cortex and subiculum were compared with direct removal of the hippocampus using acquisition of a complex radial maze task. A series of eight problems (four out of eight arms being correct) were learned under either massed (45 s) or distributed (10 min) practice conditions, thus varying contextual information. Performance of rats with subiculum/entorhinal cortex lesions was similar to that of controls in all aspects of the radial maze task; whereas animals with hippocampal lesions were impaired on nearly all dependent measures. Although the effects of varying the intertrial interval were generally small, distributed practice did serve to facilitate the performance of hippocampal rats in terms of working memory. These findings are discussed as they related to recent theorizing in the area.

Erdheim-Chester disease (ECD) is an uncommon, systemic xanthogranulomatous disorder, with distinct clinicopathological features, that is rarely expected preoperatively. We describe a case that presented in the brain of a 26-yr-old male patient and clinically mimicked the appearance of a neoplasm. The final diagnosis was a surprise. In retrospect, the diagnosis was suggested by the intraoperative "squash" preparations, which demonstrated a mixed cellular proliferation of lymphohistiocytic elements and large, multinucleated cells with vesicular nuclei, prominent nucleoli, and abundant cytoplasm. To the best of our knowledge, this is the first report detailing the cytopathological features of ECD.