Musculoskeletal Tumors

Musculoskeletal tumors

Bao Heng Department of Orthopaedic Surgery The First Affiliated Hospital

Classification  Primary  Metastatic

Main complaints  Pain  Mass  Abnormal roentgenogram

Enneking system

 T0: intracapsular  T1: extracapsular intracompartmental  T2: extracompartmental  G0: benign  G1: low grade malignant  G2: high grade malignant

 M0: metastases are absent

 M1: metastases are present

 Anatomical compartments are determined by the natural anatomical barriers to tumor growth such as cortical bone,articular cartilage,fascial septa, or joint capsules  Tumor grades are based on a combination of histological ,roentgenographic,and clinical characteristics

Biopsy  Biopsy is the ultimate diagnostic technique for evaluating neoplasma  Closed Percutanous needle aspiration or core biopsy  Open Incisional biopsy:removing a small sample of the lesion Excisional biopsy:removing the entire mass

Core needle biopsy instruments commonly used for bony specimens

Surgical techniques Curettage  Many benign bone tumors can be treated satisfactorily by curettage.  If the aggressive tumors(such as giant cell tumors) are curetted, the tumor margins should be treated with cryotherapy,PMMA cementage

 Recurrence of an aggressive tumor is likely with curettage alone  Grafting using allograft or autograft with or without internal fixation for preventing fracture

Surgical techniques  limb-sparing resection or amputation ?  Surgery radiotherapy chemotherapy  Individualization of treatment rather than rigid adherence to protocol is advisable

Benign tumors of bone

Osteochondroma Aneurysmal bone cyst

Osteochondroma  the most common of the benign bone tumors  probably developmental malformation rather than true neoplasms  Their growth usually ceases when skeletal maturity is reached.

Osteochondroma  About 90% of patients have only a single lesion  They are usually found on the metaphysis of a long bone near the physis  Distal femur the proximal tibia proximal humerus

Osteochondroma  Many of these lesions cause no symptoms and are discovered incidentally

 some cause pain by irritating the surrounding structures  the physical finding usually is a palpable mass

Indications for treatment  The lesion is large enough to be unsightly or produce symptoms from pressure on surrounding structures  Roentgenographic features suggest malignancy or when rapid growth has occurred recently

Treatment  Excision or observation  If possible the excision should consists of and en bloc resection of the osteochondroma, a rim of normal bone surrounding its base of stalk, and the entire overlying busra

Aneurysmal bone cyst  An aneurysmal bone cyst (ABC) is a solitary, expansile and erosive lesion of bone.  It is found most commonly during the second decade and the ratio of female to male is 2:1.

Aneurysmal bone cyst  The most common location is the metaphysis of the lower extremity long bones.  ABC's are thought to be a reactive process secondary to trauma or vascular disturbance.

Clinical presentation  Swelling, tenderness and pain.  Occasionally there is limited range of motion due to joint obstruction.  Spinal lesions can cause neurological symptoms secondary to cord compression.  Pathological fractures are rare due to the eccentric location of the lesion.

X ray  On plain film, an ABC is normally placed eccentrically in the metaphysis and appears osteolytic.  The periosteum is elevated and the cortex is eroded to a thin margin.

CT and MRI  CT scan can narrow the differential diagnosis of ABC by demonstrating multiple fluid-fluid levels within the cystic spaces.  MRI can also confirm the multiple fluidfluid levels

Treatment  Most lesions can be treated with currettage  Recurrence was statistically related to young age and open growth plates, and may be less likely following wide excision than following intralesional treatment by currettage.

Benign (occasionally malignant) tumors of bone

 Giant cell tumor  Chondroblastoma  Chondromyxoid fibroma  Osteoblastoma  Histiocytosis X

Giant cell tumor  Giant cell tumor mostly occurs in young adults  More than half of the tumors occur about the knee  Most patients have pain or disability or both about the involved joint

 The lesion is often located eccentriclly to the long axis of the bone  the center is most lucent with increasing density towards the periphery  these tumors often thin the cortex,and may expand into the soft tissues surrounding the bone

Treatment  Currettage with or without bone grafing has a reported recurrence rate of 15% to 60%.  Cryotherapy with liquid nitrogen  Polymethymethacrylate cementation

Malignant tumors of bone  Malignancy is determined by the ability of a neoplasm to spread beyond its site of origin and disseminate to distant parts of the body

Osteosarcoma  It is the most common primary malignancy of bone  Occurs most commonly in boys and young men in their teenage or young adult age  The most common sites are the distal femur and proximal tibia

Diagnosis  Pain and a palpable mass are usually present  Local temperature rises  Venous engorgement  Roentgenograms shows a metaphyseal lesion both producing and destroying bone

impressive swelling throughout deltoid region as well as disuse atrophy of pectoral musculature

Note radiodense matrix of the intramedullary portion of the lesion as well as soft-tissue extension and aggressive periosteal reaction

Note dramatic tumor extension into adjacent soft tissue regions

Codman trigone and sunlight

Malignant cells Osteoid matrix

Treatment  Open biopsy   Chemotherapy   Limb-sparing resection   Wide amputation

 Amputation

Ewing Sarcoma  It is relatively rare primary malignant tumor of bone  This tumor occurs most frequently in males in the second decade  Usually the long bones of the lower extremity are involved

Diagnosis  Pain and a mass  Fever and malaise  Routine roentgenograms commonly show a diaphyseal lesion with irregular destruction,periosteal new bone formation,and a permeative margin

Ewings: uniform round clear cells.

Treatment  A combination of local radiotherapy and systemic chemotherapy  Amputation

Metastatic tumors of bone  Bone is the third most common site of metastatic disease.  Cancers most likely to metastasize to bone include breast, lung, prostate, thyroid and kidney.  The ribs, pelvis and spine are normally the first bones involved

Diagnosis  Pain is the most common symptom found in 70% of patients  Pathological fractures are most common in breast cancer due to the lytic nature of the lesions. They are uncommon in lung cancer due to short life span  Paraplegia

CT and MRI  CT is more specific than bone scan and can distinguish between osteolytic and osteoblastic lesions.  MRI is the most sensitive method of detection bone metastases because cells can spotted before local bone reaction has occurred.

 Metastatic bone lesions can be described as osteolytic, osteoblastic and mixed.

 New treatments with medicines that may block bone lysis by tumor cells are currently in clinical trials (Diphosphate)

ECT

Treatment  Treatment for bone metastasis is normally palliative.  Lesions that are regarded as a risk for pathologic fracture should be surgically stabilized before a fracture occurs. The goals of surgery are to preserve stability and function of the musculoskeletal system as well as alleviate pain.  Emergency surgery is done for spinal metastasis in the hope of preserving neurological function.