SPINE Volume 39, Number 6, pp 526-527 ©2014, Lippincott Williams Sc Wilkins
IMAGING CORNER
Unknown Case Part 2 Paul Harkey, MD, and Douglas Robertson, MD
PARTI A 23-year-old Caucasian female presented to her dermatologist after noticing a growing clear bluish lesion on her right forearm. A shave biopsy performed demonstrated malignant melanoma with positive peripheral margins, and she subsequently underwent local wide excision with sentinel lymph node biopsy. An initial whole-body positron emission tomography-computed tomographic staging examination was performed followed by dedicated cervical spine magnetic resonance imaging and computed tomography.
PART 2 The case examines a single FDG-avid lytic lesion in the C7 vertebral body with severe cortical thinning (Figure 1) and enhancement on magnetic resonance image (Figure 2) in a 23-year-oId patient with newly diagnosed melanoma of the right forearm. Important differential considerations include metastatic disease, solitary fibrous dysplasia, eosinophilic granuloma, atypical hemangioma, aneurysmal bone cyst, and giant cell tumor. Given history and imaging findings, the possibility of metastatic disease could not be excluded and CT-guided biopsy was performed confirming solitary fibrous dysplasia. Fibrous dysplasia is a noninherited developmental anomaly wherein normal bone is replaced by immature fibro-osseous tissue.' Fibrous dysplasia is often asymptomatic, typically presenting in adolescents and adults younger than 30 years. Fibrous dysplasia may present in monostotic or polyostotic forms. Monostotic fibrous dysplasia accounts for 80% of cases and tends to occur most often in the ribs, long bones, and skull. Involvement of the vertebral bodies is rare only
Erom the Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA. Acknowledgment date: October 17, 2013. Revision date: November 18, 2013. Acceptance date: November 22, 2013. The manuscript submitted does not contain information about medical device(s)/drug(s). No funds were received in support of this work. Relevant financial activities outside the submitted work: consultancy. Address correspondence and reprint requests to feul Harkey, MD, Department of Radiology and Imaging Sciences, Emory University, 6325 Hospital Parkway, Johns Creek, Atlanta, GA 30097; E-mail:paul.p.harkey©emory.edu DOI: 10.1097/BRS.OOOOOOOOOOOOOl 76 526
www.spinejournal.com
Figure 1. Axial PET-CT (A) and sagittal noncontrast enhanced CT of the cervical spine demonstrates a hypermetabolic lytic lesion in the C7 vertebral body (white arrow). C7 lytic mildly expansile lesion approximates the posterior cortex with severe cortical thinning (B). PET-CT indicates positron emission tomography-computed tomography.
occurring in 2.5% of cases.'-^ Spine involvement is more likely to present in the polyostotic form of the disease.^ Fibrous dysplasia typically presents as a lytic, slightly expansile, intramedullary lesion with a sclerotic rim.' The density varies from lucent to sclerotic with mildly sclerotic "ground glass" matrix being pathognomonic. Endosteal thinning may be present but usually does not demonstrate cortical breakthrough or extraosseous soft-tissue component.^ Magnetic resonance imaging classically demonstrates intermediate to hypointense T l signal relative to normal cancellous bone, intermediate to hyperintense signal on fluid sensitive March 2014
IMAGING CORNER
Unknown Case • Harkey and Robertson
Figure 2. Tl - and T2-weighted (A, B) and Tl -weighted fat saturated post contrast (C) sagittal images of the cervical spine demonstrating a solitary C7 vertebral body lesion. The well-circumscribed C7 lesion is hypointense to adjacent normal cancel lous bone on Tl Wl (A), heterogeneously hyperintense on T2 Wl (B) and demonstrates avid post contrast enhancement (C). Notice a lack of peripheral edema or epidural component.
sequences, and heterogeneous contrast enhancement.^-^ Most lesions demonstrate increased uptake on bone scans and increased metabolic activity with positron emission tomography. Fibrous dysplasia may be complicated by fractures; malignant degeneration is exceptionally rare. Percutaneous image-guided needle biopsy of the C7 lesion was performed in this case confirming the diagnosis of fibrous dysplasia. Diagnostic image-guided core needle biopsy for musculoskeletal tumors has high yield and accuracy ranging between 70% and 98% with recent studies quoting overall yields of 88% to 91%.^'"' Heterogeneous tumors and those without extraosseous components may have lower yields, whereas those with extraosseous soft-tissue components have slightly higher yields. Solitary fibrous dysplasia of the cervical spine is uncommon, most often presenting in the polyostotic form of the
Spine
disease. Attention to the salient features of fibrous dysplasia and a sound knowledge of the radiological characteristics are important to its appropriate characterization and diagnosis.
References 1. Fitzpatrick KA, Taljanovic MS, Speer DP, et al. Imagingfindingsof fibrous dysplasia with histopatbologic and intraoperative correlation. AJR Am ] Roentgenol 2004;182:1389-98. 2. Park SK, Lee IS, Choi JY, et al. CT and MRI of fibrous dysplasia of the spine. Br] Radiol 2012;85:996-1001. 3. Sung KS, Seo SW, Shon MS. The diagnostic value of needle biopsy for musculoskeletal lesions. Int Orthop 2009;33:1701-6. 4. Jakanani GC, Saifuddin A. Percutaneous image-guided needle biopsy of rib lesions: a retrospective study of diagnostic outcome in 51 cases. Skeletal Radiol 2013;42:S5-90.
www.spinejournal.com
527
Copyright of Spine is the property of Lippincott Williams & Wilkins and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
IMAGING CORNER
Unknown Case Part 2 Paul Harkey, MD, and Douglas Robertson, MD
PARTI A 23-year-old Caucasian female presented to her dermatologist after noticing a growing clear bluish lesion on her right forearm. A shave biopsy performed demonstrated malignant melanoma with positive peripheral margins, and she subsequently underwent local wide excision with sentinel lymph node biopsy. An initial whole-body positron emission tomography-computed tomographic staging examination was performed followed by dedicated cervical spine magnetic resonance imaging and computed tomography.
PART 2 The case examines a single FDG-avid lytic lesion in the C7 vertebral body with severe cortical thinning (Figure 1) and enhancement on magnetic resonance image (Figure 2) in a 23-year-oId patient with newly diagnosed melanoma of the right forearm. Important differential considerations include metastatic disease, solitary fibrous dysplasia, eosinophilic granuloma, atypical hemangioma, aneurysmal bone cyst, and giant cell tumor. Given history and imaging findings, the possibility of metastatic disease could not be excluded and CT-guided biopsy was performed confirming solitary fibrous dysplasia. Fibrous dysplasia is a noninherited developmental anomaly wherein normal bone is replaced by immature fibro-osseous tissue.' Fibrous dysplasia is often asymptomatic, typically presenting in adolescents and adults younger than 30 years. Fibrous dysplasia may present in monostotic or polyostotic forms. Monostotic fibrous dysplasia accounts for 80% of cases and tends to occur most often in the ribs, long bones, and skull. Involvement of the vertebral bodies is rare only
Erom the Department of Radiology and Imaging Sciences, Emory University, Atlanta, GA. Acknowledgment date: October 17, 2013. Revision date: November 18, 2013. Acceptance date: November 22, 2013. The manuscript submitted does not contain information about medical device(s)/drug(s). No funds were received in support of this work. Relevant financial activities outside the submitted work: consultancy. Address correspondence and reprint requests to feul Harkey, MD, Department of Radiology and Imaging Sciences, Emory University, 6325 Hospital Parkway, Johns Creek, Atlanta, GA 30097; E-mail:paul.p.harkey©emory.edu DOI: 10.1097/BRS.OOOOOOOOOOOOOl 76 526
www.spinejournal.com
Figure 1. Axial PET-CT (A) and sagittal noncontrast enhanced CT of the cervical spine demonstrates a hypermetabolic lytic lesion in the C7 vertebral body (white arrow). C7 lytic mildly expansile lesion approximates the posterior cortex with severe cortical thinning (B). PET-CT indicates positron emission tomography-computed tomography.
occurring in 2.5% of cases.'-^ Spine involvement is more likely to present in the polyostotic form of the disease.^ Fibrous dysplasia typically presents as a lytic, slightly expansile, intramedullary lesion with a sclerotic rim.' The density varies from lucent to sclerotic with mildly sclerotic "ground glass" matrix being pathognomonic. Endosteal thinning may be present but usually does not demonstrate cortical breakthrough or extraosseous soft-tissue component.^ Magnetic resonance imaging classically demonstrates intermediate to hypointense T l signal relative to normal cancellous bone, intermediate to hyperintense signal on fluid sensitive March 2014
IMAGING CORNER
Unknown Case • Harkey and Robertson
Figure 2. Tl - and T2-weighted (A, B) and Tl -weighted fat saturated post contrast (C) sagittal images of the cervical spine demonstrating a solitary C7 vertebral body lesion. The well-circumscribed C7 lesion is hypointense to adjacent normal cancel lous bone on Tl Wl (A), heterogeneously hyperintense on T2 Wl (B) and demonstrates avid post contrast enhancement (C). Notice a lack of peripheral edema or epidural component.
sequences, and heterogeneous contrast enhancement.^-^ Most lesions demonstrate increased uptake on bone scans and increased metabolic activity with positron emission tomography. Fibrous dysplasia may be complicated by fractures; malignant degeneration is exceptionally rare. Percutaneous image-guided needle biopsy of the C7 lesion was performed in this case confirming the diagnosis of fibrous dysplasia. Diagnostic image-guided core needle biopsy for musculoskeletal tumors has high yield and accuracy ranging between 70% and 98% with recent studies quoting overall yields of 88% to 91%.^'"' Heterogeneous tumors and those without extraosseous components may have lower yields, whereas those with extraosseous soft-tissue components have slightly higher yields. Solitary fibrous dysplasia of the cervical spine is uncommon, most often presenting in the polyostotic form of the
Spine
disease. Attention to the salient features of fibrous dysplasia and a sound knowledge of the radiological characteristics are important to its appropriate characterization and diagnosis.
References 1. Fitzpatrick KA, Taljanovic MS, Speer DP, et al. Imagingfindingsof fibrous dysplasia with histopatbologic and intraoperative correlation. AJR Am ] Roentgenol 2004;182:1389-98. 2. Park SK, Lee IS, Choi JY, et al. CT and MRI of fibrous dysplasia of the spine. Br] Radiol 2012;85:996-1001. 3. Sung KS, Seo SW, Shon MS. The diagnostic value of needle biopsy for musculoskeletal lesions. Int Orthop 2009;33:1701-6. 4. Jakanani GC, Saifuddin A. Percutaneous image-guided needle biopsy of rib lesions: a retrospective study of diagnostic outcome in 51 cases. Skeletal Radiol 2013;42:S5-90.
www.spinejournal.com
527
Copyright of Spine is the property of Lippincott Williams & Wilkins and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
