RESIDENT & FELLOW SECTION Section Editor Mitchell S.V. Elkind, MD, MS Justin T. Jordan, MD Hyun-Sik Yang, MD Derek Narendra, MD, PhD Scott R. Plotkin, MD, PhD Teaching NeuroImages: Brain mass with hilar adenopathy The importance of histologic diagnosis Figure 1 Brain and chest imaging Correspondence to Dr. Jordan: jtjordan@mgh.harvard.edu Coronal contrasted T1 (A) shows heterogeneously enhancing, multifocal mass. Axial fluid-attenuated inversion recovery (B) shows vasogenic edema. Chest x-ray (C) and CT (D) demonstrate lymphadenopathy (arrows). Figure 2 Download teaching slides: Neurology.org Pathology Lymph node biopsy (A) reveals sarcoid, with noncaseating granuloma (asterisk) surrounded by lymphocytes (arrow). Brain biopsy (B) reveals glioblastoma, with pseudopalisading necrosis (asterisk) and vascular proliferation (arrow). From the Division of Neuro-Oncology (J.T.J., S.R.P.), Department of Neurology (H.-S.Y., D.N.), Massachusetts General Hospital, Boston. Go to Neurology.org for full disclosures. Funding information and disclosures deemed relevant by the authors, if any, are provided at the end of the article. © 2014 American Academy of Neurology e161 A 30-year-old man presented with weeks of progressive headaches, imbalance, and aphasia. Brain MRI revealed an enhancing left frontal mass (figure 1, A and B). Chest imaging revealed mediastinal and hilar adenopathy (figure 1, C and D). Metastatic cancer was initially suspected, but pulmonary lymph node aspiration revealed sarcoidosis (figure 2A). Subsequent brain biopsy revealed glioblastoma (figure 2B). This case emphasizes the importance of histologic diagnosis before initiating therapy. One study demonstrated nearly 50% variation in diagnosis following brain biopsy, 27% leading to a change in treatment.1 Sarcoid is associated with increased risk of certain cancers, though this has not been demonstrated for gliomas.2 AUTHOR CONTRIBUTIONS Analysis and interpretation of data: Drs. Jordan, Yang, Narendra, and Plotkin. Drafting of the manuscript: Drs. Jordan, Yang, and Plotkin. e162 Neurology 82 May 6, 2014 Critical revision of the manuscript for important intellectual content: Drs. Jordan, Yang, Narendra, and Plotkin. ACKNOWLEDGMENT The authors thank Dr. Maria Cobos Sillero, fellow in the Department of Neuropathology at the Massachusetts General Hospital, for her assistance in obtaining pathologic photographs. STUDY FUNDING No targeted funding reported. DISCLOSURE The authors report no disclosures relevant to the manuscript. Go to Neurology.org for full disclosures. REFERENCES 1. Kim JE, Kim DG, Paek SH, Jung HW. Stereotactic biopsy for intracranial lesions: reliability and its impact on the planning of treatment. Acta Neurochir 2003;145:547–555. 2. Le Jeune I, Gribbin J, West J, et al. The incidence of cancer in patients with idiopathic pulmonary fibrosis and sarcoidosis in the UK. Resp Med 2007;101:2534–2540. Teaching NeuroImages: Brain mass with hilar adenopathy: The importance of histologic diagnosis Justin T. Jordan, Hyun-Sik Yang, Derek Narendra, et al. Neurology 2014;82;e161-e162 DOI 10.1212/WNL.0000000000000393 This information is current as of May 5, 2014 Updated Information & Services including high resolution figures, can be found at: http://www.neurology.org/content/82/18/e161.full.html Supplementary Material Supplementary material can be found at: http://www.neurology.org/content/suppl/2014/05/04/82.18.e161.DC1.h tml References This article cites 2 articles, 0 of which you can access for free at: http://www.neurology.org/content/82/18/e161.full.html##ref-list-1 Subspecialty Collections This article, along with others on similar topics, appears in the following collection(s): All Oncology http://www.neurology.org//cgi/collection/all_oncology Autoimmune diseases http://www.neurology.org//cgi/collection/autoimmune_diseases Primary brain tumor http://www.neurology.org//cgi/collection/primary_brain_tumor Permissions & Licensing Information about reproducing this article in parts (figures,tables) or in its entirety can be found online at: http://www.neurology.org/misc/about.xhtml#permissions Reprints Information about ordering reprints can be found online: http://www.neurology.org/misc/addir.xhtml#reprintsus Neurology ® is the official journal of the American Academy of Neurology. Published continuously since 1951, it is now a weekly with 48 issues per year. Copyright © 2014 American Academy of Neurology. All rights reserved. Print ISSN: 0028-3878. Online ISSN: 1526-632X.