Spinal Neoplasms. First Things First!! Localize the Lesion!! Ependymomas. Common Intramedullary Lesions

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1 Acta Radiológica Portuguesa, Vol.XXIII, nº 90, pág , Abr.-Jun., 2011 Spinal Neoplasms Bruno A Policeni University of Iowa Hospitals and Clinics Assistant Professor of Radiology Disclosure of Commercial Interest Neither I nor my immediate family members have a financial relationship with a commercial organization that may have a direct or indirect interest in the content THERE IS NO SPECIFIC IMAGING PATTERN THAT RELIABLY PERMITS DIFFERENTIATION BETWEEN EPENDYMOMAS AND ASTROCYTOMAS First Things First!! Localize the Lesion!! Intramedullary Extramedullary Extradural Intradual Ependymomas Most common intramedullary tumor in adults- 60% Mean age 43 years; females predominate (slightly) Arise from ependymal cells lining central canal Slow-growing; canal expansion is typical 56% cervical; 28% thoracic; 16% lumbar 75% are isointense on T1WI; variable signal on T2WI Cystic degeneration and hemorrhage are common Hemosiderin deposition-common at periphery Heterogeneous enhancement in 65% Common Intramedullary Lesions Non-neoplastic: Acute trauma (contusion, edema ) Syringohydromyelia Syrinx-cavity in cord NOT lined by ependyma Hydromyelia-dilatation of the central canal lined by ependyma Demyelinating disease (MS) Neoplastic Ependymoma Astrocytoma ARP 101

2 Astrocytomas Second most common IM tumor overall; most common tumor in children Cervical=thoracic; M=F; mean age 21 years Typically pilocytic and diffuse fibrillary types (low grade); anaplastic astrocytomas and GBMs are rare May extend to involve the entire cord Cyst formation is common; Syrinx- above or below T1: Iso- to hypointense; T2: Hyperintense Hemorrhage is LESS COMMON than in ependymomas Virtually 100% enhance 102 ARP

3 Uncommon Rare Non-neoplastic Lesions Acute cord ischemia/stroke Myelitis (Post viral ADEM, etc) Neoplastic Lesions Hemangioblastoma Astrocytoma (anaplastic and GBMs) Non-neoplastic Lesions Vascular lesions (cavernomas, AVM, etc) Infections (sarcoid, TB, Lyme disease ) Neoplastic Lesions Metastases Lipoma Subependymoma Oligodendroglioma Ganglioma Paraganglioma Hemangioblastoma Uncommon; 1%-5% of cord tumors Peak age between 30 and 40 years One third associated with VHL syndrome 85% intramedullary or combined intramedullary/ extramedullary-intradural 50% thoracic; 40% cervical; 80% are solitary Isointense on T1WI; hyperintense on T2WI; strong enhancement; may see flow voids, etc. On angio, highly vascular mass; dense prolonged tumor stain, prominent draining veins Intramedullary Metastases Intramedullary metastases are rare 1%-3% of all intramedullary tumors No specific imaging characteristics to clearly distinguish from other intramedullary lesions Breast and lung most common Also lymphoma, leukemia, and malignant melanoma ARP 103

4 Non-neoplastic Intramedullary Pathology Subpial Lipomas Originate from fat cells in subpial region Conus region seems most common Congenital malformation with proliferating fat cells Very rare Excessive weight gain and pregnancy may aggravate 104 ARP

5 Extramedullary-Intradural Lesions Common Neurogenic Neoplasms Neurofibromas Schwannomas Meningiomas Myxopapillary Ependymomas Arachnoiditis Uncommon Lipomas Arachnoid Cysts Epidermoids/ Dermoids Drop metastases AVM Infection Paragangliomas Nerve Sheath Tumors Most common extramedullary-intradural tumors (70%-75%). 15% extradural; 15% dumbell Schwannomas more common than neurofibromas unless patient has NF Neurofibromas: M=F; years. No true capsule Localized, diffuse, or plexiform Schwannomas: M=F; years. Encapsulated 40% cystic changes; 10% hemorrhage; Neural foraminal enlargement; pedicle thinning Isointense on T1WI; Hyperintense on T2WI; Enhance Multiple in neurofibromatosis ARP 105

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7 Meningiomas Second most common EMID spinal tumor (25%) 90% intradural; 10% extradural or dumbell Females > males at 4:1; Primarily 5th-6th decade Thoracic (80%) > Cervical (16%) > Lumbar (4%) More often anterior in cervical region Below C7, more common posterior to cord Usually single unless NF 2 Iso on T1WI; iso or hyperintense on T2WI; hypointense if Ca++ Marked homogeneous enhancement ARP 107

8 Myxopapillary Ependymoma 90% of filum tumors Occur exclusively in conus and filum terminale from ependymal cells in filum Males:females = 2:1; peak between 30 and 40 years Slow growing and may fill entire lumbar spinal canal Vertebral scalloping; canal enlargement Highly vascular hemorrhage is common Iso on T1WI; hyper on T2WI; hypointense margin if hemosiderin Intense enhancement in 100% 108 ARP

9 Other Extramedullary-Intradural Neoplastic Lesions Epidermoid Cysts Less than 1% of spinal tumors Congenital-60%; Aquired-40% Strong association with lumbar puncture in neonatal period (implantation epidermoid) Iso or slightly hyperintense on T1WI; hyper on T2WI Mild rim enhancement DWI can DDx from arachnoid cysts and other lesions Dermoid Cysts Congenital (100%) Symptomatic before age 20; M=F 80% in lumbosacral or cauda Hypointense areas-? Water content from sweat gland secretions Fat hyperintensity on T1WI May cause chemical meningitis if rupture with cholesteol crystals discharged into CSF Drop Metastases CNS Primary Tumors Astrocytomas Medulloblastomas Pineal cell tumors Ependymomas Germ cell tumors Non-CNS Primary Tumors Breast Lung Lymphoma Melanoma Pituitary ARP 109

10 Extradural Metastases Most common extradural malignant tumor in adults Spine metastases occur in 15-40% of disseminated cancers Breast, lung, prostate (adults); Ewing sarcoma and neuroblastoma (children) Complications Epidural mass Pathologic fracture Cord compression Epidural Metastases Herniated discs, etc Degenerative lesions (osteophytes, ligament infolding ) Lymphoma Infection (discitis ) Extradural Lesions Common Uncommon Epidural Abscess Meningeal cysts Vertebral tumors-benign Vertebral tumors-malignant Paget s disease Epidural hematoma Epidural lipomatosis Extramedullary hematopoesis Angiolipomas 110 ARP

11 Primary Vertebral Neoplasms-Benign Hemangioma Aneurysmal bone cyst Osteoblastoma Osteochondroma Eosinophilic granuloma Giant cell tumor Hemangiomas Common benign hamartomatous lesions (10% of adults) Mean age = 50 years (range = 9-77 years) Multiple in 25-30% When discovered incidentally, male = female When symptomatic (neurologic deficit, pain ) F > M Features of compressive/aggressive hemangiomas: Location between T3 and T9 Entire vertebral body involved +/- extension to neural arch Cortex expansion with indistinct margins; soft tissue mass Irregular honeycombing (corduroy appearance) Hemangiomas (cont) Plain Films: Well-defined vertical striations or honeycombed appearance CT: Stippled, polka dot appearance (course trabeculae) MR (typical): T1WI: Hyperintense (due to fat) T2WI: Hyperintense (probably due to cellular elements within the tumor/blood) Treatment for agg. lesions: Sclerotherapy, vertebroplasty, surgery, post-op radiation therapy Aneurysmal Bone Cyst 1-2% of primary bone tumors 10-30% in spine/sacrum Arise in neural arch 80% < 20 years of age Non-malignant hamartomatous lesion-progressively destructive Most common presenting sx = pain, esp. at night (72%) Eggshell cortex; F/F levels from hemorrhage sedimentation Rx: Embolization +/- excision ARP 111

12 Giant Cell Tumors Giant Cell Tumor The spine is the 4th most common location, but only 5% of all giant cells occur here. The sacrum is most common, followed by cervical, thoracic, and lumbar spine. These tumors are more common in the vertebral BODIES. Other tumors such as ABC, osteoblastoma, and osteoid osteoma are more common in the posterior elements. Is there a history of radiation? DDx: Metastasis, plasmacytoma, GCT, chordoma 5% occur in the spine, sacrum most common Involve vertebral BODIES rather than posterior elements 112 ARP

13 Primary Vertebral Neoplasm-Malignant Chordomas Plasmacytomas Ewing s sarcoma Hodgkin s disease Malignant lymphoma Chondrosarcoma Osteogenic sarcoma Chordomas Slow-growing, rare malignant tumors arising from notochordal remnants Sacrococcygeal 50%; Clivus 35%-40%; Vertebral body 10%-15% [C (20-50%) > L > T] Rare in African-Americans Spine: M:F = 2:1; peak in 5th-6th decades Plain films/ct: Destructive lesion; primarily lytic with scattered areas of sclerosis/intratumoral Ca++ MR: Hypointense on T1WI Hyperintense on T2WI Enhancement is typical Distant mets: 5-40% (lung, liver, lymph nodes, bone) Plasmacytoma Mean age = 55 years (younger than patients with MM); M>F Most common presenting sx = pain Osteolytic expansion / compression; easily mimics metastases or benign compression fracture Hypointense on T1WI w/ curvilinear low-signal areas / infoldings caused by endplate fxs Hyperintense on T2WI Mild-mod diffuse enhancement ARP 113

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