American Journal of Emergency Medicine xxx (2014) xxx–xxx
Contents lists available at ScienceDirect
American Journal of Emergency Medicine journal homepage: www.elsevier.com/locate/ajem
Correspondence
Regarding tumefactive demyelinating lesion, its image diagnosis, and discussion To the Editor, We thank Smith et al [1] for presenting the case of tumefactive multiple sclerosis (MS). The diagnosis of tumefactive demyelinating lesion (TDL) remains a challenge to most clinicians. The expanded use of magnetic resonance imaging (MRI) in the field of emergency medicine not only enables early diagnosis in emergency department but also increases the burden of medial liability for emergency physicians. The case is classic and worth further discussions. Multiple sclerosis is an idiopathic demyelinating disorder that is typically intermittent and relapsing. According to McDonald criteria, dissemination of white matter lesions in both time and space is required to make the diagnosis. Typical locations of the MS plaque include periventricular, juxtacortical, infratentorial white matter, and spinal cord. The areas of gray matter, including cerebral cortex and basal ganglia, are usually spared. In addition, vivid terms have been developed in describing the appearance of the lesions on neuroimaging. The classic “Dawson fingers” can be appreciated as periventricular or callosal lesions that are perpendicular to lateral ventricles [2], whereas “Steiner splashes” refer to lesions distant to the ventricles. Both lesions are thought to be associated with perivascular inflammation and demyelination along medullary veins. Contrast enhancement may be seen among some MS plaques in active stage of the disease process. Tumefactive demyelinating lesion has been classified as a variant of MS, with good reasons. Firstly, both TDL and MS commonly occur in young to middle-aged women. In a most recent and largest series of Lucchinetti et al [3], among 168 patients with biopsy-proven tumor-like demyelinating disease, 79% that developed turned out to be MS on final diagnosis. However, some authorities hold the ground that TDL and MS represent 2 distinct demyelinating processes, and TDL might be in the middle between MS and acute disseminating encephalomyelitis. It is worth noting that some patients with TDL do not evolve into MS, and TDL tends to be more monophasic. Treatment response to steroids is more favorable in patients with TDL than those with classic MS [4]. In addition, despite the fact that Lucchinetti et al [3] discouraged the proposal that TDL and MS being separate disease entities in largest series, they still noticed that TDL patients have exceptionally long interval between the first and the second “MS-defining” episodes. Furthermore, there might be lower prevalence of oligoclonal band in cerebrospinal fluid of TDL patients [5]. Therefore, we must be careful when applying the concepts of MS, such as McDonald criteria, to patients with TDL. The different-entity concept has been adopted in some of the most recent publishings, including JAMA neurology [6]. Smith et al [1] also stated that a careful neurologic examination, clinical history, and MRI may obviate the need for biopsy. We would like to emphasize the value of clinical diagnosis because approximately one-third of TDL may be pathologically misinterpreted as low-grade astrocytoma, owing to confusing histologic features of hypercellularity,
astrocytic pleomorphism, and variable nuclear atypical [3]. Furthermore, chances are that patients may directly undergo treatment for brain neoplasm, such as intracranial irradiation, especially when mass effect is imminent. Under the circumstances, the clinical consideration would be crucial for pathologists to make a right diagnosis. On neuroimaging, “open ring enhancement,” which has a likelihood ratio up to 5.2 vs a neoplasm, is considered characteristic of atypical demyelinating process [7]. We also encountered a case with similar clinical and neuroimaging findings recently but with different final diagnosis. A 61-year-old woman complained of progressive right arm and leg weakness over the last month. Initial impression of TDLs was made, based on several MRI features. First of all, mass effect was relatively minimal for a real tumor. Secondly, although heterogeneity of the enhancement could be seen, the distribution of the enhancement was mostly at periphery, resembling “incomplete ring” or “open ring” (Figure A and B). Thirdly, some lesions were interpreted as “Dawson fingers (arrows in Figure C and D).” Unfortunately, the patient had suboptimal response to steroids. Stereotactic biopsy was therefore performed, and pathologic study showed diffuse large B-cell lymphoma. When retrospectively inspecting the initial MRI, we paid more attention to involvement of thalamus and basal ganglion as well as the heterogeneity of contrast enhancement (Figure D). We concluded that it was still possible to narrow down the differential diagnosis before biopsy, if a careful physical examination and a more sophisticated image interpretation could be prospectively accomplished. In conclusion, we thank Smith et al [1] for presenting this classic case, thus giving us the opportunity to share our opinions and discussions with regard to clinical images and pathology of this unique disease entity. Pen-Yuan Liao MD Department of Emergency Medicine and Department of Medical Imaging Taipei Medical University Hospital Taipei, Taiwan E-mail-address: [email protected] Cheng-Yu Chen MD Department of Medical Imaging, Taipei Medical University Hospital Taipei, Taiwan, and Imaging research center, Taipei Medical University Taipei, Taipei, Taiwan Corresponding author: Cheng-Yu Chen, MD, Taipei Medical University Hospital, 252 Wu-Shing St, Taipei City, Taiwan Tel.: +886 970749573 E-mail address: [email protected]
http://dx.doi.org/10.1016/j.ajem.2014.10.024
0735-6757/© 2014 Elsevier Inc. All rights reserved.
Please cite this article as: Liao P-Y, et al, Regarding tumefactive demyelinating lesion, its image diagnosis, and discussion, Am J Emerg Med (2014), http://dx.doi.org/10.1016/j.ajem.2014.10.024
2
Correspondence / American Journal of Emergency Medicine xxx (2014) xxx–xxx
Figure. T2-weighted fluid-attenuated inversion recovery image on axial view (A) and postcontrast T1-weighted images with gadolinium on axial (B and C) and sagittal (D) views. There are white matter lesions at bilateral cerebral hemispheres (A-C) as well as in basal ganglion and thalamus (D). The largest lesion is at left centrum semiovale, with relatively minimal mass effect for a “real” tumor. In addition, although heterogeneity of the enhancement can be seen, the enhancement is mostly at periphery, resembling “incomplete ring” or “open ring” (B). In addition, there are Dawson finger-like lesions (arrows). The patient underwent stereotactic biopsy, and the lesions were proven to be diffuse large B-cell lymphoma.
References [1] Smith C, Finan M, Axelband J, William K. It is not a tumor: a rare case of tumefactive multiple sclerosis. Am J Emerg Med 2014;32:946. [2] Ge Y. Multiple sclerosis: the role of imaging. AJNR Am J Neuroradiol 2006;27: 1165–76. [3] Lucchinetti CF, Gavrilova RH, Metz I, et al. Clinical and radiographic spectrum of pathologically confirmed tumefactive multiple sclerosis. Brain 2008;131: 1759–75.
[4] Kepes JJ. Large focal tumor-like demyelinating lesions of the brain: intermediate entity between multiple sclerosis and acute disseminated encephalomyelitis? A study of 31 patients. Ann Neurol 1993;33:18–27. [5] Altintas A, Petek B, Isik N, et al. Clinical and radiological characteristics of tumefactive demyelinating lesions: follow-up study. Mult Scler 2012;18:1448–53. [6] Brandao E, Melo-Pires M, Veira C. Relapsing-remitting tumefactive demyelination. JAMA Neurol 2014;71:366–7. [7] Masdeu JC, Quinto C, Olivera C, et al. Open-ring imaging sign: highly specific for atypical brain demyelination. Neurology 2000;54:1427–33.
Please cite this article as: Liao P-Y, et al, Regarding tumefactive demyelinating lesion, its image diagnosis, and discussion, Am J Emerg Med (2014), http://dx.doi.org/10.1016/j.ajem.2014.10.024
Contents lists available at ScienceDirect
American Journal of Emergency Medicine journal homepage: www.elsevier.com/locate/ajem
Correspondence
Regarding tumefactive demyelinating lesion, its image diagnosis, and discussion To the Editor, We thank Smith et al [1] for presenting the case of tumefactive multiple sclerosis (MS). The diagnosis of tumefactive demyelinating lesion (TDL) remains a challenge to most clinicians. The expanded use of magnetic resonance imaging (MRI) in the field of emergency medicine not only enables early diagnosis in emergency department but also increases the burden of medial liability for emergency physicians. The case is classic and worth further discussions. Multiple sclerosis is an idiopathic demyelinating disorder that is typically intermittent and relapsing. According to McDonald criteria, dissemination of white matter lesions in both time and space is required to make the diagnosis. Typical locations of the MS plaque include periventricular, juxtacortical, infratentorial white matter, and spinal cord. The areas of gray matter, including cerebral cortex and basal ganglia, are usually spared. In addition, vivid terms have been developed in describing the appearance of the lesions on neuroimaging. The classic “Dawson fingers” can be appreciated as periventricular or callosal lesions that are perpendicular to lateral ventricles [2], whereas “Steiner splashes” refer to lesions distant to the ventricles. Both lesions are thought to be associated with perivascular inflammation and demyelination along medullary veins. Contrast enhancement may be seen among some MS plaques in active stage of the disease process. Tumefactive demyelinating lesion has been classified as a variant of MS, with good reasons. Firstly, both TDL and MS commonly occur in young to middle-aged women. In a most recent and largest series of Lucchinetti et al [3], among 168 patients with biopsy-proven tumor-like demyelinating disease, 79% that developed turned out to be MS on final diagnosis. However, some authorities hold the ground that TDL and MS represent 2 distinct demyelinating processes, and TDL might be in the middle between MS and acute disseminating encephalomyelitis. It is worth noting that some patients with TDL do not evolve into MS, and TDL tends to be more monophasic. Treatment response to steroids is more favorable in patients with TDL than those with classic MS [4]. In addition, despite the fact that Lucchinetti et al [3] discouraged the proposal that TDL and MS being separate disease entities in largest series, they still noticed that TDL patients have exceptionally long interval between the first and the second “MS-defining” episodes. Furthermore, there might be lower prevalence of oligoclonal band in cerebrospinal fluid of TDL patients [5]. Therefore, we must be careful when applying the concepts of MS, such as McDonald criteria, to patients with TDL. The different-entity concept has been adopted in some of the most recent publishings, including JAMA neurology [6]. Smith et al [1] also stated that a careful neurologic examination, clinical history, and MRI may obviate the need for biopsy. We would like to emphasize the value of clinical diagnosis because approximately one-third of TDL may be pathologically misinterpreted as low-grade astrocytoma, owing to confusing histologic features of hypercellularity,
astrocytic pleomorphism, and variable nuclear atypical [3]. Furthermore, chances are that patients may directly undergo treatment for brain neoplasm, such as intracranial irradiation, especially when mass effect is imminent. Under the circumstances, the clinical consideration would be crucial for pathologists to make a right diagnosis. On neuroimaging, “open ring enhancement,” which has a likelihood ratio up to 5.2 vs a neoplasm, is considered characteristic of atypical demyelinating process [7]. We also encountered a case with similar clinical and neuroimaging findings recently but with different final diagnosis. A 61-year-old woman complained of progressive right arm and leg weakness over the last month. Initial impression of TDLs was made, based on several MRI features. First of all, mass effect was relatively minimal for a real tumor. Secondly, although heterogeneity of the enhancement could be seen, the distribution of the enhancement was mostly at periphery, resembling “incomplete ring” or “open ring” (Figure A and B). Thirdly, some lesions were interpreted as “Dawson fingers (arrows in Figure C and D).” Unfortunately, the patient had suboptimal response to steroids. Stereotactic biopsy was therefore performed, and pathologic study showed diffuse large B-cell lymphoma. When retrospectively inspecting the initial MRI, we paid more attention to involvement of thalamus and basal ganglion as well as the heterogeneity of contrast enhancement (Figure D). We concluded that it was still possible to narrow down the differential diagnosis before biopsy, if a careful physical examination and a more sophisticated image interpretation could be prospectively accomplished. In conclusion, we thank Smith et al [1] for presenting this classic case, thus giving us the opportunity to share our opinions and discussions with regard to clinical images and pathology of this unique disease entity. Pen-Yuan Liao MD Department of Emergency Medicine and Department of Medical Imaging Taipei Medical University Hospital Taipei, Taiwan E-mail-address: [email protected] Cheng-Yu Chen MD Department of Medical Imaging, Taipei Medical University Hospital Taipei, Taiwan, and Imaging research center, Taipei Medical University Taipei, Taipei, Taiwan Corresponding author: Cheng-Yu Chen, MD, Taipei Medical University Hospital, 252 Wu-Shing St, Taipei City, Taiwan Tel.: +886 970749573 E-mail address: [email protected]
http://dx.doi.org/10.1016/j.ajem.2014.10.024
0735-6757/© 2014 Elsevier Inc. All rights reserved.
Please cite this article as: Liao P-Y, et al, Regarding tumefactive demyelinating lesion, its image diagnosis, and discussion, Am J Emerg Med (2014), http://dx.doi.org/10.1016/j.ajem.2014.10.024
2
Correspondence / American Journal of Emergency Medicine xxx (2014) xxx–xxx
Figure. T2-weighted fluid-attenuated inversion recovery image on axial view (A) and postcontrast T1-weighted images with gadolinium on axial (B and C) and sagittal (D) views. There are white matter lesions at bilateral cerebral hemispheres (A-C) as well as in basal ganglion and thalamus (D). The largest lesion is at left centrum semiovale, with relatively minimal mass effect for a “real” tumor. In addition, although heterogeneity of the enhancement can be seen, the enhancement is mostly at periphery, resembling “incomplete ring” or “open ring” (B). In addition, there are Dawson finger-like lesions (arrows). The patient underwent stereotactic biopsy, and the lesions were proven to be diffuse large B-cell lymphoma.
References [1] Smith C, Finan M, Axelband J, William K. It is not a tumor: a rare case of tumefactive multiple sclerosis. Am J Emerg Med 2014;32:946. [2] Ge Y. Multiple sclerosis: the role of imaging. AJNR Am J Neuroradiol 2006;27: 1165–76. [3] Lucchinetti CF, Gavrilova RH, Metz I, et al. Clinical and radiographic spectrum of pathologically confirmed tumefactive multiple sclerosis. Brain 2008;131: 1759–75.
[4] Kepes JJ. Large focal tumor-like demyelinating lesions of the brain: intermediate entity between multiple sclerosis and acute disseminated encephalomyelitis? A study of 31 patients. Ann Neurol 1993;33:18–27. [5] Altintas A, Petek B, Isik N, et al. Clinical and radiological characteristics of tumefactive demyelinating lesions: follow-up study. Mult Scler 2012;18:1448–53. [6] Brandao E, Melo-Pires M, Veira C. Relapsing-remitting tumefactive demyelination. JAMA Neurol 2014;71:366–7. [7] Masdeu JC, Quinto C, Olivera C, et al. Open-ring imaging sign: highly specific for atypical brain demyelination. Neurology 2000;54:1427–33.
Please cite this article as: Liao P-Y, et al, Regarding tumefactive demyelinating lesion, its image diagnosis, and discussion, Am J Emerg Med (2014), http://dx.doi.org/10.1016/j.ajem.2014.10.024
