Presentation
Back pain and left lower limb numbness.
Patient Data
L4 vertebral body marrow infiltrative lesion. It elicits low signal on T1, high signal on T2 W and STIR WI. This is associated with an extra-osseous epidural component which is effacing the CSF, indenting the theca and encroaching upon the left neural exit foramen.
Diagnosis: Features are suggestive of metastatic lesion or plasmacytoma.
Low grade FDG uptake by L4 vertebral body and the extra-osseous epidural component with SUVmax 2. No bony lytic or sclerotic changes in the involved bone.
Gross of two specimens:
1) Bone biopsy: Multiple hard uncuttable bony pieces with attached soft tissues, collectively measured 7 cm.
2) Soft tissue biopsy: Multiple soft grayish white fragments, collectively measured 1 x 1 cm, totally submitted. Margins could not be assessed due to fragmentation of the specimen.
Microscopic:
Sections examined from the bony biopsy revealed bony tissue with attached fibromuscular and fatty tissues, free of tumor tissue.
Sections examined from the soft tissue biopsy reveal pieces of growth composed of lobules separated by thin fibrous bands and showing myxoid background entangling cords and groups of uniform round cells with pale eosinophilic cytoplasm and large vacuolated cells.
Diagnosis: Undifferentiated epithelioid cell growth impressive of chordoma.
Case Discussion
Chordomas are rare tumors arising from the notochord remnant, commonly occurring in the axial skeleton, including the clivus of the skull base, vertebral bodies of the mobile spine and sacrococcygeal regions. Chordomas are locally aggressive tumors yet uncommonly metastasize.
Chordoma is a rare tumor of vertebral bodies but is the second most common primary spinal malignancy after lymphoproliferative disease
Chordomas commonly affect the adult population with a median age at diagnosis of 60 years.
Radiographic features include:
CT: lytic lesion with extra-osseous component, likely to show intra-tumoral calcifications.
MR: low T1, remarkably high T2 signal (due to the presence of vacuolated cellular components which contain high fluid content), and moderate gadolinium enhancement.
FDG PET-CT: may demonstrate an increase in SUV on PET but, in general, they do not have characteristic imaging features on functional studies.