Osteosarcoma

Presented by:SANA ARMAN

• OSTEO = Bone

• SARCOMA = Malignant tumour of connective tissue

OVERVIEWOVERVIEW• Introduction • Epidemiology• Classification• Skeletal Distribution• Etiology• Clinical and Radiographic features• Histopathology• Staging• Treatment and Prognosis

INTRODUCTIONINTRODUCTION

• 2nd most common primary malignant bone tumor after multiple myeloma.

• Arise from primitive mesenchymal bone forming cells

• Formation of osteoid directly by sarcoma cells.

EPIDEMIOLOGYEPIDEMIOLOGY

Involves any age but highest occurrence in adolescence i.e,10 to 25 yrs

Males > Females Blacks > Whites

OSTEOSARCOMA

Primary Secondary

Central(intra-

medullary)

Intra Cortical

Peripheral(juxta-cortical)

High Grade

Low Grade

• Paraosteal• Periosteal• High grade

surface OS

• Conventional OS• Telangiectactic OS• Small cell OS

Sequelae of .•Pagets Disease•Chemotheraphy•Chondrosarcoma- dedifferentiation

CLASSIFICATICLASSIFICATIONON

INTRA CORTICALINTRA MEDULLARY(central)

JUXTA CORTICAL(surface)

• 95%• Metaphysis• Fast growing

• Very rare• Diaphysis

• 5%• Metaphysis or Diaphysis• Slow growing

ETIOLOGYETIOLOGY• Exact cause is unknown.• Risk Factors

– Rapid bone growth– Environmental

Radiation Oncogenic virus

– Genetic Mutation of RB gene Li Fraumeni syndrome – Mutation in p53 tumour suppressor gene Rothmund Thomson syndrome (Autosomal Recessive)

– Pre existing lesions – Ex: Fracture of bone, Infarcts, Pagets disease etc

SKELETAL DISTRIBUTIONSKELETAL DISTRIBUTION• Sites

– Metaphysis > Diaphysis > Epiphysis

[89%] [10%] [1%]

• Distal Femur [40%]• Proximal Tibia [20%]• Proximal Humerus [10%]• Others – Jaw [8%] or

Pelvis [8%]

CLINICAL AND CLINICAL AND RADIOGRAPHIC FEATURESRADIOGRAPHIC FEATURES Clinically• Pain• Swelling• Loosening of teeth• Paresthesia• Nasal obstruction

Radiographically

• Codmans triangle• Sunburst appearance• Symmetric widening of periodontal

ligament.

Radiographically

• Codman’s triangle : Formed at the angle between the elevated periosteum and underlying surface of cortex.

• Sunburst appearance: Due to osteogenesis within the tumour.

Radiographically

• Symmetric widening of periodontal ligament space: Due to tumour infiltration.

Radiographically

PATHOLOGYPATHOLOGY GROSSLY :• Grey white• Bulky mass• Codmans triangle• Cut surface shows areas of

hemorrhages and necrotic bone.

g

HISTOLOGICALLYHISTOLOGICALLY : • Sarcoma cells - Undifferentiated mesenchymal

stromal spindle shaped cells with hyperchromatic nuclei.

• Osteogenesis – Osteoid matrix and bone is found interspersed in the areas of tumour cells.

Osteiod production

Spindle cells with hyperchromatic nuclie

CONVENTIONAL OSTEOSARCOMACONVENTIONAL OSTEOSARCOMA

Osteoblastic Chondroblastic Fibroblastic

OSTEOBLASTIC OSTEOSARCOMAOSTEOBLASTIC OSTEOSARCOMA

CHONDROBLASTIC OSTEOSARCOMACHONDROBLASTIC OSTEOSARCOMA

FIBROBLASTIC OSTEOSARCOMAFIBROBLASTIC OSTEOSARCOMA

Histologic variants• Telangiectactic: Large,cavernous,dilated

vascular channels.

• Small cell: Small,uniform tumour cells.

• Fibrohistiocytic: Resembles malignant fibrous histiocytoma

• Anaplastic: Marked anaplasia

• Well differentiated: Minimal cytologic atypia

EVALUATIONEVALUATIONMedical history and physical examinationConfirmed by investigations• Plain x ray• MRI scan• CT scan• Angiogram• Bone scan• Laboratory studies• Biopsy

STAGINGSTAGING• To stratify risk groups Stages :• Stage I - Low grade lesions• Stage II - High grade lesions• Stage III - Metastatic disease Substages :• A - Intramedullary lesions• B - Local extramedullary spread

TREATMENT (plan) TREATMENT (plan) • Radiological staging• Biopsy to confirm diagnosis• Preoperative chemotherapy• Repeat radiological staging (access chemo response, finalize

surgical treatment plan)• Surgical resection with wide margin• Reconstruction using one of many techniques

• Post op chemotherapy based on pre op response

ChemotherapyChemotherapy

• Preoperatively - Neoadjuvant chemotherapy (to decrease spread of tumour cells during surgery; treat micrometastasis)

• Postoperatively - Adjuvant chemotherapy

SurgerySurgery

For safe and complete removal of tumor Methods :a.Amputation

b.Limb savage procedure

c. Rotationplasty

• In mandible - Hemimandibulectomy

• Maxillectomy is difficult to perform due to the involvement of adjacent structures like maxillary sinus, pterygopalatine fossa and orbital fossa.

PROGNOSISPROGNOSIS

5 year survival rate

• Localised tumours : 60-80%

• Metastatic tumours : 15-30%