Transcript Aneurysmal Bone Cyst (ABC) - University at Buffalo School

June 2007
Tumor Unknown Conference
Case 1
C.G. - 21 year old male with a history
of curretage and bone grafting of a
distal ulnar lesion eighteen months ago
Aneurysmal Bone Cyst (ABC)
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Osteolytic, hyperplastic, hyperemic-hemorrhagic
lesion of unknown origin
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Epidemiology
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80% before 20 years of age, rare after 30 years old
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Most common sites: long bones LE > UE
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30% secondary lesions due to pre-existing tumor
Radiographs
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Eccentric, expansile, lytic lesion of metaphysis
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Cortical attenuation or destruction
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Rim of reactive bone
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Fluid-Fluid levels on MRI are characteristic
ABC
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Histology
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Cavernous spaces filled with blood, lacking
endothelial lining
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Fibroblastic cells, multinucleated giant cells
and thin strands of bone
ABC
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Treatment
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Excision, curettage, and bone grafting
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Resection in case of an expendable bone.
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Other modalities include adjuvant cryo,
chemical cautery, injection of steroids
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Radiation not recommended
Prognosis
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Local recurrence rate approx 10%, increased if
open physis
Case 2
T.K. - 18 year old male with
asymptomatic left ankle swelling for
several months
Aneurysmal Bone Cyst (ABC)

Osteolytic, hyperplastic, hyperemic-hemorrhagic
lesion of unknown origin

Epidemiology


80% before 20 years of age, rare after 30 years old

Most common sites: long bones LE > UE

30% secondary lesions due to pre-existing tumor
Radiographs

Eccentric, expansile, lytic lesion of metaphysis

Cortical attenuation or destruction

Rim of reactive bone

Fluid-Fluid levels on MRI are characteristic
ABC

Histology

Cavernous spaces filled with blood, lacking
endothelial lining

Fibroblastic cells, multinucleated giant cells
and thin strands of bone
ABC


Treatment

Excision, curettage, and bone grafting

Resection in case of an expendable bone

Other modalities include adjuvant cryo,
chemical cautery, injection of steroids

Radiation not recommended
Prognosis

Local recurrence rate approx 10%, increased if
open physis
Case 3
S.P. - 12 year old male with left hip
pain after a minor fall
Unicameral Bone Cyst

Benign fluid filled cystic lesion of bone
of unknown cause

Epidemiology

5-15 years of age

Male > Female

Proximal humerus most common, followed
by proximal femur
Unicameral Bone Cyst
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Symptoms
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Asymptomatic unless fracture occurs
Radiographs
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Central lytic lesion of metaphysis
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Attenuation and slight expansion of cortex
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Fluid filled on CT/MRI
Unicameral Bone Cyst
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Histology

Thin fibrous membrane lining cyst

Few macrophages, giant cells, leukocytes
and slivers of bone and osteoid
Unicameral Bone Cyst
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Treatment

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Cysts become inactive at skeletal maturity and
typically resolve without surgical intervention
Multiple treatments including curettage and
bone grafting, steroid injections have been tried
with variable efficacy
Fractures tend to lead to resolution of cyst
Displaced fractures are the only absolute
surgical indication
Case 4
A.M. - 87 year old female with an
asymptomatic posterior thigh soft tissue
mass present for many years, the patient
reports that it has increased in size over the
past three months
Lipoma
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Benign tumor of mature fat
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Classification

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Superficial: (more common)

contained within subcutis
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prevalence for back, neck, proximal limbs
Deep: (less common)
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Age
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within muscle or intermuscular spaces
Most frequent between 40-60 years old
Presentation
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Slow growing asymptomatic mass
Lipoma
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Imaging
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Resembles normal fat on all CT and MRI images
Histology
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Mature fat cells (lipocytes)
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Rarely small areas of hemmorrage, necrosis, calcification
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Absence of lipoblasts and pleomorphic, hyperchromatic
nuclei differentiate lipoma from liposarcoma
Treatment
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Marginal Excision
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Local recurrence is rare
Liposarcoma
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Primary malignant tumor arising from fat
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15% of all soft tissue tumors
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Usually presents at 40-60 years of age
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Two main types
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Myxoid: usually low grade Stage I lesion
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Cytogenic marker: reciprocal translocation on chromosome 12
Pleomorphic: usually high grade Stage II lesion
Liposarcoma
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Can be very large at presentation due to anatomic
location and deep-seated, slow-growing nature
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Also typically not painful or tender
MRI
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Similar to other soft tissue sarcomas,
with multilobular configuration
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T1) Low intensity
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T2) Bright signal
Liposarcoma
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Myxoid Histology
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Sheets of lipocytes or lipoblasts interspersed in myxomatous amorphous matrix with low cell to matrix ratio

Fine branching capillaries with arborization pattern,
resemble a road map
Pleomorphic Histology
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More cellular
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Lacks plexiform capillary network
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May have large, bizarre lipoblasts with abundant
eosinophilic cytoplasm
Liposarcoma
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Treatment
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Preoperative adjuvant radiation therapy
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Wide surgical excision
Treatment

Wide local excision

Radiotherapy may be used to control local recurrence
and lessen the risk of metastasis

Prognosis

Five year survival: well differentiated 85-100%,
myxoid 75-95%, round cell and pleomorphic
20-50%, dedifferentiated 30%
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Local recurrence 10% with adequate margins
Case 5
T.S. - 44 year old male with six month
history of an anterior shoulder mass
Pleomorphic Sarcoma


Malignant soft tissue tumor of
mesechymal origin
Epidemiology

7000 new cases of soft tissue sarcomas
diagnosed yearly
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Lesions classified according to direction of
differentiation
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Can be caused by radiation exposure
Pleomorphic Sarcoma
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Symptoms
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Enlarging mass, most are large, deep and
firm at diagnosis
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Can be painless or painful
Radiographs
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MRI is the best imaging modality
Pleomorphic Sarcoma
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Histology
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Treatment
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Dedifferentiated mesenchymal cells
Grade of tumors determined on histology
Radiation therapy
Wide surgical excision, limb salvage if possible
Prognosis depends on
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Tumor Grade
Size (> 5 cm)
Location superficial or deep to fascia
Case 6
D.E. - 15 year old male with left knee pain after
falling from a skateboard three weeks ago
Chondroblastoma
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Benign tumor composed of chondroblasts
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Epidemiology

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Male: female is 3:1
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10-20 years of age
Localization
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Epiphysis, apophysis, or short bone
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Extension to metaphysis and even through
physeal plate.
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Proximal humerus>distal femur>proximal
tibia>proximal femur
Chondroblastoma
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Clinical Presentation
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Pain, usually referred to a joint
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Moderate to long duration
Imaging
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XR: Osteolytic with smooth boarders, eccentric
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CT/MRI: Well defined boarders, fuzzy mottled
intratumoral radio densities
Chondroblastoma
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Gross
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Rubbery soft with sharp limits toward the
surrounding bone
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Pink to gray to tan in color
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Whitish foci or chalky granules (calcifications)
Histo
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Highly cellular: Chondroblasts and Giant cells
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Pathognomonic: calcium in fine granules
deposited on a reticular network producing a
“chicken-wire” pattern
Chondroblastoma
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DDX
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Giant Cell Tumor, Clear Cell Chondrosarcoma,
Chondroma, Chronic Brodie’s abscess
Treatment
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Stage 1, 2, and some stage 3: intralesional
excision after frozen confirmation
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Stage 3: wide intra or extraarticular segmental
resection
Prognosis

Local recurrence < 10% after curettage in stage
3 tumors, rare after wide resection
Case 7
T.L. - 49 year old male with left elbow
pain and swelling after a fall
Osteomyelitis
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Bone Infection

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Acute hematogenous, subacute focal disease,
and chronic types
Epidemiology
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Most common in infants and children
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Declining incidence due to better dx/tx

Staph aureus most common in all age groups
Osteomyelitis
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Symptoms

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Pain, decreased ROM, swelling, erythema,
fever, malaise, irritability
Radiographs
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Delayed changes on imaging (2-4 weeks)

Lytic lesion with mottled appearance usually
in metaphysis
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Periosteal elevation/reaction
Osteomyelitis
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Histology
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Mixed cell population
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Sequestrum: dead cortical bone
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Involucrum: new cortical bone
Treatment
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Biopsy/culture
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Acute
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IV antibiotics ± surgical debridement
Chronic
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IV antibiotics with surgical debridement
Case 8
K.M. - 13 year old female with a painful
soft tissue mass of the left anterior knee
Epithelioid Granulomatous Inflammation
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Chronic inflammation
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A compact collection of cells of the mononuclear
phagocyte system
Types
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Low Turnover: Foreign body
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High Turnover: Epithelioid, hypersensitivity
Treatment

Marginal excision
Case 9
N.S. - 19 year old male with a chest wall mass
discovered on an x-ray for suspected bronchitis
Calcifying Fibrous Tumor of Pleura
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Very rare benign fibrous tumor of pleura
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Composed of hyalinised collagen with psammomatous calcification and inflammatory infiltrate

Rare cases reported in the literature are in patients
less than 30 years old
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Imaging shows circumscribed lesion with
increased density centrally which represents areas
of calcification

Treatment is typically excisional biopsy to rule
out sarcoma
Case 10
A.Z. - 70 year old female with left distal
thigh pain and swelling for several weeks
B-Cell Lymphoma
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Neoplasm of B-Lymphocytes
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Most common Non-Hodgkin lymphoma
Fourth through seventh decades
Primary lymph node disease
Extranodal sites
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More than 50% of patients will have
extranodal involvement at diagnosis
Primary bone lymphomas are rare
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(5% of extranodal disease)
Most common site is the thigh
Large B Cell
Lymphoma of Soft Tissue
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Symptoms
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Radiographs
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Often mild and prolonged before diagnosis
Lytic lesion with “moth eaten” appearance
Histology

Dense sheets of round cells
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CD-20 positive
Large B Cell
Lymphoma of Soft Tissue
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Treatment

Combined chemotherapy and radiation to
bony sites
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Chemo: Cytoxan, adriamycin, vincristine,
and prednisone
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If remission is obtained by 6 cycles of chemo,
cure rates approximate 60-70%