Paget`s Disease Of Bone And Bone Tumors1

Paget`s Disease of Bone and Bone Tumors 1 Dr. Rima Safadi 27/7/2008

Paget`s Disease of Bone • Disorganized formation and remodeling of bone unrelated to functional requirements • Abnormal osteoclastic function • Etiology: • Unknown; maybe paramyxovirus infection. – Latency in osteoclast progenitor cells

• Genetic predisposition – Chromosome 18q locus

Paget’s Disease Pathogenesis 3 overlapping phases 2. Predominantly osteolytic phase Increased osteoclastic resorption

3. Active stage of mixed osteolysis and osteogenesis Abnormal osteoblastic deposition and increased vascularity

4. Sclerotic phase Dense bone and decreased vascularity

Paget’s Disease of Bone Clinical Features • Age: patients over age 40. – More common with increasing age. – 3% overall incidence

• Geographic differences in incidence – More in UK, Australia, North America –

• Gradual onset. Chronic course.

• Involves multiple areas of skeleton – mainly axial skeleton, more in sacrum – skull and femur – Jaw lesions more common in maxilla • May involve single or few bones or disseminated

• Deformity of bones • Bone pain • Increased pathologic fracture

Paget’s Disease of Bone Clinical Features • Enlargement of skull and facial bones. • Narrowing of skull foramina may cause cranial nerve dysfunction

Paget’s Disease Oral Features – Enlargement of jaws – Widening of alveolar ridges. – Dentures don’t fit – Spaces between teeth – Facial deformity – Derangement of occlusion

Widened and flattened palate

Paget’s Disease Oral Features When teeth are involved: • Ankylosis • Hypercementosis • Root resorption in osteolytic phase • Postextraction hemorrhage in active phase • More prone to infection in sclerotic phase

Paget’s Disease of Bone Radiographic Features • Osteoporosis in early phases • In later stages, patchy osteosclerosis – poorly-defined radiopaque areas (“cotton wool”)

• In the skull: thickening of the outer plate, loss of distinction between tables

• Teeth: – Loss of lamina duras – Hypercementosis – Ankylosis

Loss of diploe

Paget’s Disease • Microscopic: – Increased bone turnover – Bone resorbtion and deposition reflects the disease stages. • The resorbed areas are filled by cellular and vascular fibrous marrow • Simultaneous osteoclastic and osteoblastic activity • Dense sclerotic bone

– Cementum may also show disorganized remodeling • Hypercementosis and ankylosis

– Osteosarcoma

• Laboratory: – Increased serum alkaline phosphatase – Serum calcium and phosphorus occasionally increased usually within normal

Numerous reversal lines

Paget’s Disease Treatment and Prognosis • Calcitonin and diphosphonates inhibit osteoclastic resorption. • Paget’s disease is usually not fatal but has complications. – Increased incidence of malignant neoplasms (<1% of patients), most commonly osteosarcoma.

Questions/Comments?

Giant Cell Lesions of Bone • Central giant cell granuloma • Giant cell tumor of bone • Giant cell lesions of hyperparathyroidism (“brown tumor”) • Cherubism

Central Giant Cell Granuloma Clinical Features • Probably reactive and not neoplastic – Reactive to heamodynamic changes: trauma or heamorrhage

• • • • •

Most common in young adults Female predominance Only occurs in the jaws More common in mandible (~70%) Involves anterior part of the jaws

Central Giant Cell Granuloma • Clinically: – Swelling of bone – Rapid growth or – symptomless

• Non-aggressive lesions: asymptomatic, slow growth, does not perforate cortex, low recurrence • Aggressive lesions: rapid growth, perforates cortex, higher recurrence • Most CGCG are non-aggressive

Central Giant Cell Granuloma Radiographic Features • Well-demarcated or poorly defined radiolucent lesion • Unilocular or multilocular • Can cause thinning, expansion or perforation of cortical plate • Root displacement or resorption.

Central Giant Cell Granuloma Microscopic Features • Fibrous connective tissue, multinucleated giant cells, hemorrhage and hemosiderin

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Central Giant Cell Granuloma Treatment and Prognosis • Simple enucleation and curettage • Recurrence rate following curettage is about 15-20% • Long-term prognosis is good. • Need to exclude hyperparathyroidism

“True” Giant Cell Tumor of Bone • Giant cell tumors occur in long bones, very rare in Jaws • more aggressive • higher recurrence rate • may metastasize in 10% of cases • distinct from central giant cell granuloma and represents a true neoplasm.

Questions/Comments??

Exostoses Localized bony protuberances, non neoplastic • Torus palatinus • Torus mandibularis • Buccal exostosis • Palatal exostosis

Torus palatinus • Etiology: genetic versus environmental • Arises at the midline of the hard palate

Nodular torus

Spindle torus and flat torus

Lobular torus

• Can slowly increase in size • Peak prevalence is in adult- dynamic

Torus mandibularis • At the lingual aspect • Present above the mylohyoid line • 90% bilateral • Varies in size • Can correlate with bruxism • Trt: surgical removal for denture construction

Exostoses

Subpontine exostosis

Buccal exostosi s

Palatal exostosis

Exostosis • Histopathology

Dense Bone Island • Sclerotic bone • Premolar region of the mandible • Well defined not surrounded by radiolucent line • Separated or attached to root apex

Tumors of Bone • Source: marrow, cartilage, bone, fibrous, vascular • Benign and malignant

Benign tumors • Osteoma • Osteoblastoma • Chondroma

Osteoma • • • • •

Benign slow growing tumor Mature bone Mandible>maxilla Sub periosteal or central D/D: dense bone island, exostosis

Histology: compact or cancellous

Osteoma • Multiple osteomas of the jaws in Gardner syndrome – AD – Polyposis coli marked tendency for malignant change – Fibrous tumors – Sebacous cysts of the skin – Multiple impacted and supernumerary teeth

Osteoblastoma • Histologically and radiographically resembling cementoblastoma – Not related to the roots of teeth

Cementoblastoma

Osteosarcoma • Most common primary malignant tumor in jaws • Age of onset around 30 • May be central, or in relation to periosteum – Juxtacortical have better prognosis than intramedullary

Osteosarcoma • Presenting signs and symptoms – Swelling – Pain, toothache – Loose or displaced teeth – Bleeding – Paresthesia

• Increased incidence in Paget’s disease

Osteosarcoma • Radiographic Features – Radiolucent, radiopaque, or mixed – Margins are poorly defined – “Sun-ray” appearance: bony trabeculae radiating from periphery or periosteum. Present in only 25% of cases and not unique to osteosarcoma.

– Early feature: localized symmetrical widening of periodontal ligament space

Osteosarcoma

Osteosarcoma • Microscopic: malignant osteoblasts and direct formation of abnormal osteoid and bone • Treatment and Prognosis – Radical surgery, radiation therapy, chemotherapy – Mandibular lesions have better prognosis