Primary bone tumours of the Spine:Imaging and Pathology

David Ritchie

Robin Reid

Incidence: primary spinal (38) and sacral (14) tumoursSBTR (2000-09), 52 patients

Benign 21 Malignant 31

ABC 6 (1) Chordoma 10 (4)

Osteoblastoma 6 (1) Ewings 8 (3)

Osteoid osteoma 5 Chondrosarcoma 5 (1)

Giant Cell Tumour 1 (1) Myeloma 3 (1)

Eosinophilic Gran 1 Plasmacytoma 2 (1)

Chondroma 1 Osteosarcoma 2 (1)

Fibrous Dysplasia 1 Haemangioendoth 1

(x) Sacral tumourC spine (7), D spine (21), L spine (10)

Spine – Tumours - Location

ANTERIOR – Malignant• Metastases

• Myeloma

• Lymphoma

Exceptions• Eosinophilic granuloma

• Haemangioma

• Giant cell tumour

POSTERIOR - Benign

• Osteoblastoma

• Osteoid osteoma

• Aneurysmal bone cyst

• Osteochondroma

Exceptions• Sarcoma

KM, SBTR 4706

17F, 2/12 Hx of intermittantthoracolumbar painWorse at night

Aneurysmal bone cyst

• Children/ young adults

• Metaphysis of long bones, spine

• Sponge-like mass, blood filled spaces

• Septa, fibroblasts, giant cells, osteoid

• Mitoses, but normal

• No endothelial lining

• Recur in 25%

Aneurysmal Bone Cyst SBTR 4278, RW

Clinical and Imaging• 80% 1st - 2nd decades

• Benign expansile lesion containing thin-walled blood filled cavities

• Thin cortical shell and foci of cortical destruction

• Absent matrix

• Fluid-fluid levels caused by blood product sedimentation

Differential diagnosis • Osteoblastoma

• Giant cell tumour

• Telangiectatic osteosarcoma

• Brown tumour of hyperparathyoidism

T2W

T1W

SS, SBTR 439450M, Increasing LBP, Right buttock pain radiating to kneeNo bladder or bowel problems

AE1/3 and S100AE1/3 and S100

ChordomaChordoma

• NeuroaxisNeuroaxis– Base of skullBase of skull– SacrumSacrum– VertebraeVertebrae

• Arises from notochord remnantArises from notochord remnant

• Local recurrence and extension usualLocal recurrence and extension usual

• Metastasis in <10%Metastasis in <10%

Chordoma

Differential diagnosis

• Metastasis / Lymphoma / Myeloma • Chondrosarcoma• Giant cell tumour • Osteosarcoma

Clinical

• 50% of 1º malignant sacral tumours• 50% of chordomas arise in sacrum• 4-7th decades, 2M:1F• Slow growing painful mass • Low grade but recurrence common• Metastases late (5 – 43%) • 5 year survival rate 60-80%

T2W

STIR

Recurrent / metastatic chordoma

Surgery for Sacral Tumours

• Preserve power/sensation legs - S1 roots • Preserve bowel / bladder function - S2 roots • Retention of sexual function - S3 root - M, S2 - F

Stability of the lumbo-sacral junction

Preservation of neurological function

Raque et al. Treatment of neoplastic diseases of the sacrum. J Surg Oncol 2001; 76: 301

DH, SBTR 4604P,10.2841CHI 0710726171Chordoma LV3

PC, SBTR 4591

31M, 2yr Hx mid thoracic / periscapular pain Scoliosis

Osteoid Osteoma

• Central nidus (<1cm) of vascular/gritty tissue• Subperiosteal or cortical lesions provoke

intense reactive new bone formation• Nidus: active osteoblasts forming bone

osteoclastic remodelling, very vascular• Natural history: sometimes recur following

incomplete excision• Rare spontaneous regression suggests

osteoid osteoma may not be neoplastic

Osteoid Osteoma

Clinical and Imaging

• Benign bone forming tumour • 10% in axial skeleton • 90% in 2nd – 3rd decades, 3M:1F• Night pain relieved by non-steroidal analgesia• Usually arise posterior elements• Nidus <15mm, lucent but often mineralisations• Reactive sclerosis / peri-tumoral oedema • CT best cross-sectional imaging technique

Differential diagnosis

• Chronic infection• Bone island

SPINE

T2W CT

28M, LBPR sciatica

Osteoblastoma

• “Giant osteoid osteoma” 2-10cm• 1% of bone tumours• Wide age range, mainly 10-30 years• Spine (posterior elements), long bones• Swelling, dull pain,nerve compression,

Histology as in osteoid osteoma• Local recurrence after curettage (?

multifocality)

OsteoblastomaClinical and Imaging• Uncommon benign bone forming tumour

• Histologically similar to osteoid osteoma

• 90% in 2nd – 3rd decades, 2M:1F

• 3 imaging patterns

– Large “osteoid osteoma”

– Expansile mineralised lesion

– Occasionally aggressive

Differential diagnosis • Osteoid osteoma• Aneurysmal bone cyst• Osteosarcoma

SR, SBTR 4623

• 72F

• Bilateral lower limb pain & loss of power and paraesthesia both thighs

Ritchie

Chondrosarcoma – conventional

• de novo (primary) or from a pre-existing enchondroma or exostosis (secondary)

• Central,within the medullary canal or peripheral on bone surface

• 10% of malignant primary bone tumours• predominantly middle aged and elderly • Males: females; 2:1• axial skeleton, pelvis, ribs, shoulder girdle

proximal femur and humerus. Hands and feet rare

Proportion of tumours

% metastatic rate

grade 1 64% 5%

grade 2 21% 14%

grade 3 15% 75%

Chondrosarcoma

Clinical and Imaging• 7 - 12% of primary malignant spinal tumours• 4th – 6th decades• Low grade - geographic growth pattern• High grade - permeative growth pattern• CT detects mineralisation in 90% • MR – Unmineralised cartilage shows lobules of

high signal on T2W separated by low signal septae

• Calcifications may display signal voids

T1W

T2W

CTDifferential diagnosis• Chordoma • Metastasis• Myeloma • Giant cell tumour

SBTR 4322, CH, 18F,4/12 Hx right buttock / thigh pain and inguinal paraesthesia More recently bilateral thigh and buttock pain Urinary problems and decreased perianal tone

Osteosarcoma

a malignant tumour whose cells form osteoid or bone

CH

OsteosarcomaClinical and Imaging• 5% of primary malignant spinal

tumours

• 4th decade (older than long bone)

• Associated with Paget’s, DXRT

• Mixed lytic / sclerotic appearance

• Aggressive, soft tissue extension

• Osteoid mineralisation

T1W T2W

T1WCT

Differential diagnosis

• Ewings• Chondrosarcoma • Metastasis• Osteoblastoma• Lymphoma