Tuesday, June 23, 2009

Lytic Bone Lesion

LYTIC BONE LESION


By Dr. KM Liau



When you see lytic bone lesion think of FOGMACHINE.

Most of the lytic lesions are benign conditions with the exception of 'M' (Metastasis and Multiple Myeloma)

SOLITARY LYTIC BONE LESION

Differential Diagnosis (Mnemonic = FOGMACHINES)

F = Fibrous Dysplasia

O = Osteoblastoma

G = Giant Cell Tumour

M = Metastasis / Myeloma

A = Aneurysmal Bone Cyst

C = Chondroblastoma

H = Hyperparathyroidism(brown tumours)/ Hemangioma

I = Infection

N = Non-ossifying Fibroma

E = Eosinophilic Granuloma / Enchondroma

S = Solitary Bone Cyst

FIBROUS DYSPLASIA

Dysplasia = Abnormal tissue development.

Etiology unknown

Most common between 3-15 years of age.

Deformity of long bone (Most common deformity is varus of the proximal femur-"Shepherd's crook deformity") and bone pain.

Shepherd's crook deformity

Fundamental Abnormality Of Fibrous Dysplasia

The fundamental abnormality is replacement of medullary bone by fibrous tissue.

Characteristic X-ray findings:

1. Endosteal scalloping

2. Cortical thinning

3. Homogenous ground-glass appearance

4. Angular deformity at the level of the lesion.

Fibrous Dysplasia

McCune Albright's Syndrome

1 Polyostotic

2. Sexual precocity

3. Cafe-au-lait spots (Coast of Maine)

4. Almost always in a female

Coast of Maine cafe au-lait spot - The lesion has a rough, irregular border

AP view of the left hand demonstrates multiple large expansile "bubbly" lytic lesions

FIBROUS DYSPLASIA - TREATMENT

TREATMENT:

1. Observation -Prevention of deformity and fracture.

2. Pathologic fracture managed by standard methods according to the site of fracture. Suboptimal alignment will not remodel with time and should not be tolerated.

Surgical treatment principles:

1. Recurrent fracture require internal fixation with intramedullary rods and bone graft.

2. Severe angular deformities- treated with closing wedge osteotomies, bone grafting, and internal fixation.

3. Leg length discrepancy- treated with epiphysiodesis of contralateral limb at the appropriate age.

Fibrous dysplasia of both femur treated with internal fixation

Fibrous Dysplasia Link List

Fibrous Dysplasia
Learn more about fibrous dysplasia

OSTEOBLASTOMA

Osteoblastoma is a solitary, benign and self-limited tumour that produces osteoid and bone. (Large form of osteoid osteoma; >2cm)

Occurs in the posterior element of spine, the metaphysis or diaphysis of long bones, and rarely in the pelvis.

Characteristic X-ray findings of Osteoblastoma

1. Radio-lucent defect with a central density due to ossification.

2. The lesion is well circumscribed and may have a surrounding sclerosis.

Osteoblastoma of proximal humerus

GIANT CELL TUMOUR

Aetiology unknown)
(Probably arise from zone of osteoclastic activity in skeletally immature patients).

Histology:

Multinucleated osteoclastic giant cells intermixed throughout a spindle cell stroma

Characteristic X-Ray finding of Giant Cell Tumour

1. Solitary expansile lytic lesion

2. Location: Metaphyseal and Juxta-articular (adjacent to joint)

3. Multiple septation (soap bubble appearance)

4. No reactive sclerosis

5. No periosteal reaction in absence of fracture

Giant cell tumour of distal radius

Giant cell tumour of proximal tibia

Multiloculated lesion with a very characteristic appearance (honeycomb-like pattern) (left); Pure lytic lesion (right)

Giant Cell Tumour Link List

Giant Cell Tumour
Learn more about Giant Cell Tumour

METASTASIS - RENAL CELL CARCINOMA

When you see a patient over age 40 with hematuria and a large 'blow-out' bone lesion, think of kidney cancer.

Since the kidney is comprised of mostly blood vessels, kidney cancer metastases may also have a rich blood supply, and may bleed extensively (even audibly) after a simple biopsy.

Other lytic but non-expansile metastasis include lung and thyroid cancer.

Renal cell carcinoma metastasis to pelvis

Skeletal Metastasis Link List

Skeletal Metastasis
Learn more about skeletal metastasis
Skeletal Metastasis AAOS
Skeletal Metastasis at AAOS

Multiple Myeloma

It is the most common primary bone tumour and is found in the spine, skull, ribs, sternum and pelvis.

It is a malignant tumour of plasma cells that causes widespread osteolytic bone damage.

The average patient age is over 50 years old.

Men are affected twice as often as women.

It tends to involve the entire skeleton.

Characteristic X-Ray Finding of Multiple Myeloma

Multiple myeloma appears on X-rays as decreased bone density with a lot of "punched out" holes in the bone.

Erosion begins intramedullarly and progresses through the cortex.

These destructive lesions are not surrounded by the white rim of bone seen in other types of destructive lesion.

Multiple "punched-out" lesion in the skull

Multiple Myeloma of long bones

Plasma Cells

The osteolytic lesions are caused by increased osteoclastic resorption that is stimulated by cytokines released by-the plasma cells.

Plasma cells

Multiple Myeloma Link List

Multiple Myeloma
Learn more about multiple myeloma

Aneurysmal Bone Cyst

Hallmark is ballooned-out appearance

Eccentric location

Marked cortical thinning and erosion and periosteal elevation.

Buttress of periosteal reaction (to differentiate from simple bone cyst)

Usual containment by a thin shell of periosteum

Lesion rarely penetrates the articular surface or growth plate.

Radiographic differential diagnosis includes:

1. Simple bone cyst

2. Giant cell tumor of bone

3. Telangiectatic osteosarcoma

4. Angiosarcoma.

Anuerysmal bone cyst of proximal femur

ANEURYSMAL BONE CYST - SPINE

Posterior elements of the vertebrae are also frequent location of anuerysmal bone cyst.

Chondroblastoma

Chondroblastomas are radiolucent lesions that typically occupy the epiphysis (or apophysis) of long bones.

They tend to be small (<>

Plain radiograph of the distal femoral epiphysis in a 12-year-old boy. This image shows a chondroblastoma with a characteristica

Plain radiograph of the greater trochanter in a 24-year-old man. Chondroblastomas that occur in the proximal femur are 3 times m

Hemangioma

Benign lesions characterized by vascular spaces lined with endothelial cells.

50% of osseous hemangiomas are found in the vertebral bodies (thoracic especially) and 20% in the calvarium.

The remaining lesions are found in the tibia, femur and humerus.

The radiological appearance can be quite striking and depends on the location of the lesion.

The lesions are often poorly defined, appearing as a somewhat localized area of abundant, dilated vessels, some of which may be on the surface of the b

Hemangioma of tibia

Hemangioma of vertebra

HEMANGIOMA SPINE

On CT scan, vertebral body lesions have a "polka dot" pattern as the vessels are seen in cross section.

Calvaria lesions are lytic and resemble radiating wheel spokes.

INFECTION (OSTEOMYELITIS)

IN CHILDREN:

Pathomechanism

1.Trans-physeal vessels closed
2.Primary focus of infection is in metaphysis

Findings

* Sequestration frequent
* Periosteal elevation
* Small single / multiple osteolytic areas in metaphysis
* Extensive periosteal reaction parallel to shaft (after 3-6 weeks)
* Shortening of bone with destruction of epiphyseal cartilage
* Growth stimulation by hyperemia and premature maturation of adjacent epiphysis

NON OSSIFYING FIBROMA

AKA: Nonosteogenic fibroma, fibroxanthoma, xanthogranuloma of bone.

30 to 40% children over two years have one or more lesions.

Most common between 8-20 years of age.

Usually occur in metaphysis of one (75%) or more (25%) of the tubular bones.

Most often occur in lower extremities around knee.

Fewer than 10% occur in upper extremities.

Non-ossifying Fibroma

X Ray Characteristics:

1. Geographic

2. Lytic

3. Multilobulated

4. Metaphyseal

5. Usually intramedullary

6. Eccentric (situated in the periphery of bone)

7. Well-marginated

8. Sclerotic rim

9. Endosteal scalloping

Non-ossifying fibroma of tibia

NON OSSIFYING FIBROMA 3

Most lesions heal spontaneously by being replaced with normal bone.

Migrate away from epiphysis with growth of patient.

May undergo pathologic fracture (picture).

Do not undergo malignant transformation

EOSINOPHILIC GRANULOMA

Solitary, non-neoplastic proliferation of histiocytes.

Part of a spectrum of Langerhan's cell histiocytosis, formerly known as histiocytosis X.

Localized lesion in bone or lung and occurs most commonly in children aged 5 to 10.

The skull may have a lesion with sharp, punched out borders (picture).

ENCHONDROMA

Benign cartilaginous tumor.

Develops in the medullary cavity.

Usually solitary (multiple lesions in syndromes).

Arise from ectopic rests of hyaline cartilage.

Occur mostly in 2nd to 3rd decade.

Most common site is small bones of the hands and feet.

Most occur in the proximal phalanx.

Usually asymptomatic and found insidiously.

Rapid growth with pain and swelling should raise suspicion of either a pathologic fracture or, less likely, malignant transformation.

Enchondroma X Ray Finding

X-Ray finding:

Well-defined lytic and slightly expansile lesion (in small bones).

Usually have some internal calcification and endosteal thinning.

Internal calcifications tend to resemble "rings and arcs" of cartilage calcification .

There is an expansile, lucent, well-defined ("geographic") lesion with swirls and rings of chondroid calcification at the

Enchondroma in the distal femur. Note the lesion is geographic with response from surrounding bone. Cartilagenous matrix is pr

Enchondroma Link List

Enchondroma
Learn more about enchondroma

Multiple Enchondromatosis (Ollier Disease)

This is nonhereditary disorder which usually presents in childhood.

The affected extremity is shortened (asymmetric dwarfism) and sometimes bowed due to epiphyseal fusion anomalies.

Patients are at risk for development of sarcomas, specifically osteosarcomas and chondrosarcomas. These occur in approximately 25 % of patients.

Multiple enchondromas are present in this radiograph of the left hand in a patient with Ollier disease. Lesions for unknown rea

The left distal femur is widened with an "Erlenmeyer" deformity. The left femur is also shortened relative to the right. The med

New The Most Important Thing

MULTIPLE ENCHONDROMATOSIS (MAFUCCI SYNDROME)

Nonhereditary

Even more rare than Ollier's disease

Multiple cavernous hemangiomas of soft tissues, usually in extremities (digits)

Look for phleboliths in hemangioma

The typical appearance of Mafucci syndrome is illustrated by this radiograph.

Multiple enchondromas are encountered along with phleboliths in soft tissue hemangiomas.

MAFUCCI SYNDROME

Growth disturbance of affected bones

Malignant transformation common -75%

Hemangioma may become sarcoma in 5% of cases.

Mafucci syndrome

Mafucci syndrome represents enchondromatosis with soft tissue hemangiomas, usually in the hands and feet.

As with Ollier disease, there is typically a shortening of the long bones.

These patients are at higher risk for sarcomatous transformation of both the vascular and cartilaginous portions of the disease.

Multiple enchondromas are encountered along with phleboliths in soft tissue hemangiomas.

MAFUCCI SYNDROME

Intra operative finding of hemangioma

SOLITARY BONE CYST

Pathogenesis - Theories

Focal defect in metaphyseal remodelling causing blockage in interstitial drainage .

This increases the intraosseous pressure leading to focal bone necrosis and accumulation of fluid .

Fluid causes bony destruction due to presence of prostaglandin, oxygen free radicals, interleukin, cytokines and metalloproteinases .

Prostaglandin - stimulate osteoclasts to resorb bone and subsequently leads to more fluid accumulation.

SOLITARY BONE CYST 3

Indication for treatment- To reduce the potential risk of pathological fracture and to alleviate pain

Options:
- Steroid Injection
- Curretage and bone graft
- Injection of fibrosing agents
- Percutaneous autologus bone marrow injection
- Percutaneous demineralized bone matrix injection

Solitary (Unicameral) Bone Cyst

Purely lytic lesion

Metaphyseal , diaphyseal region

Concentric lesion

Septated

Thin cortex

Solitary bone cyst of proximal humerus with fallen leaf sign signifying pathological fracture

Simple Bone Cyst Link List

Unicameral Bone Cyst
Learn more about simple bone cyst

Wise Sayings About Solitary Lucent Lesions

1. With a long lesion in a long bone, think of fibrous dysplasia.

2. Simple cyst, enchondroma, and fibrous dysplasia can mimic each other and can be hard to distinguish. Thus, when you think of one of these three entities, also think of the other two.

3. Giant cell tumors nearly always occur near a joint surface.

4. For lucent lesions in patella, calcaneum, and most apophyses, one should include the classic epiphyseal entities such as chondroblastoma, giant cell tumors and aneurysmal bone cys

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1 comment:

  1. Renal cell cancer is one of the few tumors in which well-documented cases of spontaneous tumor regression in the absence of therapy exist, but this occurs very rarely and may not lead to long-term survival. The incidence of Renal cell cancer seems to be increasing, though it isn't clear why. The exact cause of renal cell cancer has not been determined but Smoking and misuse of certain pain medicines probably can affect the risk of developing renal cell cancer.

    Renal Cell Carcinoma Metastais

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