Mila Blaivas

Brain biopsy in primary angiitis of the central nervous system

Article abstract To determine the yield of brain biopsy and the predictive value of clinical features and ancillary studies, we retrospectively analyzed hospital chart data from 61 consecutive patients suspected of having primary angiitis of the CNS (PACNS). Biopsies disclosed PACNS in 22 (36%), alternative diagnoses in 24 (39%), and no diagnosis in 15 (25%). Clinical indicators and angiography were not useful predictors of PACNS. Brain biopsy should be the primary diagnostic tool in this setting because of the poor reliability of other indicators and because of the high yield of alternative diagnoses requiring different management.

The pathology of REM sleep behavior disorder with comorbid Lewy body dementia

A patient with REM sleep behavior disorder who subsequently developed probable Lewy body dementia is now reported to have a definite pathologic diagnosis of Lewy body dementia. Examination of brain revealed Lewy bodies as well as marked neuronal loss in brainstem monoaminergic nuclei-particularly locus coeruleus and substantia nigra-that inhibit cholinergic neurons in the pedunculopontine nucleus mediating atonia during REM sleep.

Autopsy findings in eight patients with fatal H1N1 influenza.

A novel H1N1 influenza A virus emerged in April 2009, and rapidly reached pandemic proportions. We report a retrospective observational case study of pathologic findings in 8 patients with fatal novel H1N1 infection at the University of Michigan Health Systems (Ann Arbor) compared with 8 age-, sex-, body mass index-, and treatment-matched control subjects. Diffuse alveolar damage (DAD) in acute and organizing phases affected all patients with influenza and was accompanied by acute bronchopneumonia in 6 patients. Organizing DAD with established fibrosis was present in 1 patient with preexisting granulomatous lung disease. Only 50% of control subjects had DAD. Peripheral pulmonary vascular thrombosis occurred in 5 of 8 patients with influenza and 3 of 8 control subjects. Cytophagocytosis was seen in all influenza-related cases. The autopsy findings in our patients with novel H1N1 influenza resemble other influenza virus infections with the exception of prominent thrombosis and hemophagocytosis. The possibility of hemophagocytic syndrome should be investigated in severely ill patients with H1N1 infection.

MIB-1 Proliferation Index Predicts Survival among Patients with Grade II Astrocytoma

Abstract. The purpose of this study was to determine whether a relationship existed between MIB-1 labeling index (LI) percentages and survival in patients with grade II astrocytomas. From archival paraffin-embedded surgical specimens of 50 patients of the University of Michigan Medical Center with World Health Organization grade II astrocytomas, 22 patients had a Ki-67 LI of less than or equal to 2.0; and 28 patients had a MIB-1 LI of more than 2.0. Over a median follow-up interval of 10 years, ranging up to 16 years, 23% (n = 5) died of tumor in the first group while 82% (n = 23) died in the second group, a distinct difference in survival between these groups. Univariate analysis showed that a high MIB-1 predicted shorter survival (p < 0.0001), and that increased age was associated with shorter survival (p = 0.007). Gender, tumor location and radiotherapy had no significant association with survival. When adjusting for these (excluding tumor location) in the Cox proportional hazards model simultaneously, MIB-1 and age were independently prognostic. The hazard ratios were 1.301 per 1% MIB-1 LI (p = 0.0001), and 1.045 per year of age (p = 0.0028). From other studies, we know that histopathologic grade and age predict survival for glioma patients. However, even within grade II astrocytomas there is still a wide heterogeneity in how long a patient survives. We conclude that among grade II astrocytomas older patients and, independently, patients with higher MIB-1 labeling index have shorter survival.

Clinical and pathologic features of focal myositis

To clarify the nosology of focal myositis (FM), we report the clinical and pathologic features of eight patients presenting with focal enlargement of one muscle. Most patients improved without immunosuppressive therapy, and none developed polymyositis. Pathologic features were those of an inflammatory myopathy, with muscle fiber hypertrophy and moderate to severe inflammation. In most cases, a clustering of tightly packed muscle fibers, enveloped by a thick bundle of fibrosis, was associated with the diagnosis of FM. Immunohistochemistry showed T cell predominance within the interstitial infiltrates in all cases. No evidence of vasculitis was present. Our findings suggest that FM is a benign condition that has certain clinical features separating it from other inflammatory myopathies. Pathologic changes, such as large clusters of nesting muscle fibers surrounded by thick fibrosis, are more characteristic of FM than polymyositis.

Quantification of intramuscular nerves within the female striated urogenital sphincter muscle

Objective To analyze the quantity and distribution of intramuscular nerves within the striated urogenital sphincter and test the hypothesis that decreased nerve density is associated with decreased striated sphincter muscle and cadaver age. Methods Thirteen cadaveric urethras (mean age 47 years, range 15–78 years) were selected for study. A sagittal histologic section was stained with S100 stain to identify intramuscular nerves. The number of times that a nerve was seen within the striated urogenital sphincter (nerve number) was counted. The number of axons within each nerve fascicle was also counted. Regression analysis of nerve density against muscle cell number and age was performed. Results Remarkable variation was found in the quantity of intramuscular nerves in the striated urogenital sphincter of the 13 urethras studied. The number of nerves ranged from 72 to 543, a sevenfold variation (mean 247.1 ± standard deviation 123.2), and the range of number of axons was 431 to 3523 (2201 ± 1152.6). The larger nerve fascicles were seen predominantly in the distal (13.1 ± 5.7 axons per nerve) compared with the proximal part of the striated urogenital sphincter (1.2 ± 2). Reduced nerve density throughout the striated urogenital sphincter correlated with fewer muscle cells (P = .02). Nerve density also decreased with advancing age (P = .004). Conclusion Remarkable variation in the quantity of intramuscular nerves was found. Women with sparse intramuscular nerves had fewer striated muscle cells. Intramuscular nerve density declined with age.

Sinonasal undifferentiated carcinoma: Case series and review of the literature

OBJECTIVE AND IMPORTANCEWe report on four cases of sinonasal undifferentiated carcinoma (SNUC), a relatively newly described clinicopathological entity of the nasal cavity and paranasal sinuses. SNUC tends to present with advanced-stage disease, often with intracranial invasion, and requires an aggressive treatment approach that includes surgical resection. A review of the literature identified several reports of SNUC in pathology and otolaryngology journals since its initial description in 1986, but no report has yet appeared in the neurosurgery literature. CLINICAL PRESENTATIONFour patients presented with various symptoms related to the nose and/or orbit, including one or more of the following: obstruction, epistaxis, decreased visual acuity, diplopia, and pain. All patients were noted to have masses in the nasal cavity or paranasal sinuses, with or without intracranial extension. INTERVENTIONAll four patients underwent multimodal treatment with chemotherapy, radiotherapy (60–65 Gy), and aggressive surgical resection via a combined bifrontal craniotomy and a subcranial approach to the anterior cranial fossa. Three of four patients died as a result of their disease, an average of 15 months after diagnosis. Only one patient remains alive, although with metastatic intracranial disease, at 24 months after diagnosis. CONCLUSIONSNUC is a rare neoplasm with a poor prognosis despite an aggressive multimodal approach to treatment. On the basis of our experience, we advocate radical resection as part of the initial combined therapy for patients who present with locally advanced, nonmetastatic disease but we suggest reserving surgery for patients with early brain invasion until there has been a radiographically proven central nervous system response to adjuvant therapy.

Low diagnostic yield of sural nerve biopsy in patients with peripheral neuropathy and primary amyloidosis

Patients with primary amyloidosis may develop peripheral neuropathy as an early feature. Sural nerve biopsy is reported to be a sensitive method for diagnosing amyloidosis in such patients. We identified nine patients, ultimately diagnosed as having amyloidosis, who were referred for peripheral neuropathy of undetermined etiology. In six, a sural nerve biopsy demonstrated no amyloid. Subsequent examination of other tissue or of the contralateral sural nerve eventually resulted in the correct diagnosis. We conclude that sural nerve biopsy may be less sensitive than previously believed for the diagnosis of amyloidosis in patients with peripheral neuropathy secondary to amyloid. When the clinical suspicion of amyloidosis is high, a nondiagnostic sural nerve biopsy should not discourage the performance of further investigative studies.

Inhibition of vascular endothelial growth factor (VEGF)-A causes a paradoxical increase in tumor blood flow and up-regulation of VEGF-D.

Purpose: Vascular endothelial growth factor (VEGF)-A is an important mediator of angiogenesis in almost all solid tumors. The aim of this study was to evaluate the effect of VEGF-A expression on tumor growth, perfusion, and chemotherapeutic efficacy in orthotopic 9L gliosarcomas. Experimental Design: Stable 9L cell lines underexpressing and overexpressing VEGF-A were generated. Anatomic, susceptibility contrast, and continuous arterial spin-labeling magnetic resonance imaging were used to quantify the volume, blood volume, and blood flow of tumors orthotopically grown from these and wild-type 9L cells. Histologic, immunohistochemical, and quantitative reverse transcription-PCR analyses were also done on excised tumors. Finally, the effects of carmustine chemotherapy were also evaluated. Results: Orthotopic tumors underexpressing VEGF-A had slower growth rates (increased median survival), greater blood flow, vessel density, and VEGF-D expression, but no statistical difference in blood volume and chemotherapeutic sensitivity, compared with tumors with wild-type levels of VEGF-A. Tumors overexpressing VEGF-A had faster growth rates, greater blood volume, vessel density, and blood flow but no statistical difference in VEGF-D expression and chemotherapeutic sensitivity compared with wild-type VEGF-A-expressing tumors. Conclusion: Blood volume and blood flow are independent and different biomarkers of tumor perfusion. Therefore, both should be measured when characterizing the efficacy of antiangiogenic therapies. Underexpression of VEGF-A does not result in complete inhibition of angiogenesis. Moreover, these tumors have a different perfusion phenotype, suggesting that angiogenesis is mediated by an alternative pathway. The results indicate that VEGF-D is a plausible alternative mediator of this angiogenesis.

Magnetic resonance imaging of ethyl-nitrosourea-induced rat gliomas: a model for experimental therapeutics of low-grade gliomas.

Human low-grade gliomas represent a population of brain tumors that remain a therapeutic challenge. Preclinical evaluation of agents, to test their preventive or therapeutic efficacy in these tumors, requires the use of animal nobreak models. Spontaneous gliomas develop in models of chemically induced carcinogenesis, such as in the transplacental N-ethyl-N-nitrosourea (ENU) rat model. However, without the ability to detect initial tumor formation, multiplicity or to measure growth rates, it is difficult to test compounds for their interventional or preventional capabilities. In this study Fisher-334 rats, treated transplacentally with ENU, underwent magnetic resonance imaging (MRI) examination in order to evaluate this approach for detection of tumor formation and growth. ENU-induced intracranial cerebral tumors were first observable in T2-weighted images beginning at 4 months of age and grew with a mean doubling time of 0.487 ± 0.112 months. These tumors were found histologically to be predominately mixed gliomas. Two therapeutic interventions were evaluated using MRI, vitamin A (all-trans retinol palmitate, RP), as a chemopreventative agent and the anti-angiogenic drug SU-5416. RP was found to significantly delay the time to first tumor observation by one month (P = 0.05). No differences in rates of tumor formation or growth rates were observed between control and RP-treated groups. MRI studies of rats treated with SU-5416 resulted in reduction in tumor growth rates compared to matched controls. These results show that MRI can be used to provide novel information relating to the therapeutic efficacy of agents against the ENU-induced tumor model.