Exam 3: Benign Tumors (Part 2)

Osteoid Osteoma

-benign skeletal neoplasm composed of osteoid and woven bone

-less than 1.5cm in diameter

-represents 12% of benign bone tumors

What is the age of occurrence for an osteoid osteoma?

10-25 years old

Clinical features of an osteoid osteoma:

-tender to touch and pressure

-local pain (95-98%) weeks to years in duration that is worst at night and decreased by activity

-salicylates give relief in 20-30 minutes in 75-90% of cases

Osteoid osteoma locations:

-meta diapyseal of long bones (proximal femur, proximal tibia and humerus)

-spine predominately in the posterior elements of lower thoracics + upper lumbars creating a painful scoliosis (tumor on concave side of curve)

-no bone is exempt

Radiographic features of an osteoid osteoma:

-lesion is the radiolucent NIDUS usually

Treatment and prognosis of osteoid osteoma:

-complete surgical excision of the nidus

-little chance of recurrence

-vertebral body lesioins may be irradiated

-can go away on its own after ~30+ months

Advanced imaging findings of an osteoid osteoma:

-increased uptake (double density sign) on bone scan

-CT for precise detection and localization of the nidus

-angiography shows highly vascularized nidus with intense circumscribed blush appearing in early arterial phase

Osteoma

-benign tumor arising in membranous bone

-commonly found in adulthood

-well circumscribed round extremely dense lesion ~2cm in size

-mostly asymptomatic

-associated with gardener's syndrome (multiple osteomas, colonic polyposis, and soft tissue fibromas)

Osteoma locations:

-para nasal sinuses (frontal and ethmoid)

-inner/outer table of the calvarium (usually from external table)

-occassionally mandible or nasal bones

Enchondroma

-MC BENIGN TUMOR OF THE HAND

-benign cartilaginous growth in the medullary cavity of bones preformed in cartilage

-arise in residual islands of cartilage left behind

-usually asymptomatic

-pathologic fracture may occur

Locations of enchondromas:

-40% occur in the small bones of the wrists and hands

-long bones (femur, tibia, humerus, radius, ulna, feet, ribs)

-usually central and meta-diaphyseal

Radiographic features of enchondromas:

-round/oval lucency with fine marginal line

-central = MC

-stippled or punctate calcifications

-possible cortical thinning and expansion

Treatment and prognosis of enchondromas:

-usually require no treatment

-symptomatic lesion in long bones may require surgical curettage and bone chips

-malignant degeneration in ~1% but percentage increases the closer to the axial skeleton

Enchondromatosis/Ollier's Disease

-non hereditary failure of cartilage ossification

-early childhood presentation

-hand and feet deformity

-multiple enchondromas

-approximately 10% malignant degeneration rate

What syndrome is present within Ollier's disease?

maffucci syndrome

Maffucci Syndrome

multiple soft tissue hemangiomas; % of malignant change increases

Hemangioma

solitary vascular neoplasm which is slow growing and composed of newly formed capillary, cavernous, or venous blood vessels

Hemangiomas occur commonly during the _____ of life

4th-5th decade

Signs and symptoms of hemangiomas:

-most are asymptomatic (leave it alone)

-symptomatic spinal lesions are due to expansion causing spinal stenosis and cord compression (need MRI)

Hemangiomas are the MC benign tumor of the ____

spine

Locations of hemangiomas:

-vertebral body in the lower thoracics/upper lumbars

-calvarium with predilection for the frontal bone

Radiographic spinal features of hemangioma:

-exaggerated/accentuated vertical trabeculations (accordion/corduroy/honeycomb appearance)

-posterior bulge of cortex

-extra osseous extension beyond bony lesion causing cord compression

-paravertebral soft tissue extension

Radiographic skull features of hemangioma:

-

CT will show a ____ appearance that is indicative of a hemangioma

polka dot

Chondroblastoma

rare benign bone tumor that occurs BEFORE the cessation of enchondral bone growth

Chondroblastoma age of occurrence:

8-59 years old with a peak incidence between 5-25 years old and

Chondroblastoma signs and symptoms:

-often symptomatic for months to years prior to treatment

-mild joint pain, tenderness, joint swelling and limitation of motion

Location of chondroblastoma

-develops around an apophysis or epiphysis in a subarticular location

-2/3 found in lower extremities (proximal femure, distal femur, proximal tibia, proximal humerus, tarsal bones)

Radiographic features of a chondroblastoma:

-round or oval eccentric lytic lesion of an epiphysis or apophysis 1-6cm in diameter

-well defined sclerotic margin

-lobulated in 50%

-irregular/punctate calcifications in 25-50%

-periostitis along metaphysis in 30-50%

Fibrous cortical defect clinical features:

-most common 2-8 years old with peak at 7-8 years of age

-affects 30% of children

-fibrous cell rests

-asymptomatic

Location of fibrous cortical defects:

-METAPHYSEAL cortex of long bones of the lower extremity (posterior medial surface of distal femur, tibia, fibula, proximal femur)

-ilium, ribs, proximal humerus

Radiographic features of a fibrous cortical defect:

-round lytic lesion 1-2cm in diameter with a well defined sclerotic margin

-eccentric and metaphyseal

-oval and extending parallel to the long axis which cold produce cortical thinning and expansion

-lytic or bubbly appearance with a sclerotic border

-may be multilocular

Non-ossifying fibroma clinical features:

-most common 8-20 years of age with 75% occuring in 2nd decade

-affects 30% of children

-asymptomatic

Location of non-ossifying fibromas:

-affects long bones of the lower extremity (distal tibia, distal femur, proximal tibia, fibula, occasionally proximal humerus)

-eccentric and metadiaphyseal

Radiographic features of non-ossifying fibroma:

-eccentric multilocular ovoid lesion along the long axis

-lytic lesion >2cm in length

-dense sclerotic border

-endosteal scallopping + thinning and bulging

-migrates toward diaphysis

Fibrous cortical defects and non-ossifying fibromas can be referred to as:

fibrous xanthoma

Paget's Disease

-tumor like process characterized by bone lysis and followed by extensive repair attempts

-bone undergoes increased resorption followed by increased bone formation

-higher incidence in northern latitudes

-named osteitis deformans by sir paget

Pagets Disease: Clinical Information

-most age >55 years and >85 years in 10%

-male to female ratio = 2:1

-etiology is thought to be viral

-likely to have some genetic component as well

-most are asymptomatic

-bone pain is most common symptom

-bony deformity

-neurologic complications

-cardiac issues

Newly formed bone in pagets disease has a disorganized trabecular pattern leading to:

bone softening

Osseous locations of Paget's disease:

-usually polyostotic and asymmetric

-pelvis (MC), lumbar spine, thoracic spine, proximal femur, calvariium, scapula, distal femur, proximal tibia, proximal humerus

Laboratory fiindings of Paget's disease:

-increased hydroxyproliine

-increased alkaline phosphatase

-normal serum calcium and phosphorus

Stages of Paget's Disease:

-stage 1: osteolytic/destructive

-stage 2: mixed/combined

-stage 3: sclerotic/ivory

-stage 4: malignant degeneration

Radiological features of Paget's:

-increased or decreased density

-coarsened irregular trabecular pattern

-thickened cortex (internal and external)

-bone expansion

-subarticular to diaphysis

-osseous deformity (bone softening deformity)

-pathologic fractures

Skull features of Paget's:

-osteoporosis circumscripta

-cotton wool appearance

-basilar invagination with foraminal encroachment

Osteoporosis Circumscripta

well defined geographic lysis (map like) of the frontal and occipital regioin; represents lytic phase of Paget's

Long bone features of Paget's:

-begins at bone end (subarticular)

-candle flame/blade of grass sign

-cortical thickening and irregular disorganized trabeculae

-bowing deformities (shepards crook, saber shin)

-banana fracture

Candle flame/blade of grass sign:

-advancing edge of the lytic phase

-bone is regenerating where cortex is thickened and paget's moves toward direction of candle flame sign

Banana Fracture

-tiny horizontal cortical infractions (looser lines) on CONVEX surfaces of lower extremity

-represent insufficiency factors

-present in Paget's disease

Pelvic features of Paget's:

-thickening of iliopectineal line and cortical lines of the pubic bones (rim sign/brim sign)

-cortical thickening

-widened pubic bones

-thickening and disorganization of trabeculae

-acetabular protrusion

Spinal features of Paget's:

-coarse vertical trabeculae

-thickened endplate

-ENLARGED VB

-picture frame vertebra

-ivory vertebra

-pathological fracture

Possible complications of Paget's:

-peripheral nerve compression, brainstem compression and spinal stenosis

-hearing loss, blindness, facial palsy

-hyperemia of overlying skin

-shepards crook/saber shin deformity

-basilar invagination

-banana fracture in longg bones

-pathologic fractures

-high output cardiac failure

-DJD

-malignant transformation

Fibrous Dysplasia

-benign fibro-osseous developmental anomaly of the mesenchymal precursor of bone, manifested as a defect in osteoblastic differentiation and maturation

-occurs in 1st and 2nd decades of life

Types of fibrous dysplasia:

1. monostotic: affects ribs, proximal femur and craniofacial bones

2. polyostotic: unilateral and asymmetric long bone involvement

3. polyostotic with endocrine abnormalities (mccune albright syndrome)

Signs and symptoms of fibrous dysplasia:

-usually dependent on type of disease and extent

-many are asymptomatic while others may have pain secondary to deformity/fracture

McCune Albright Syndrome

-polyostotic fibrous dysplasia that presents with cafe au lait spots and can cause precocious puberty in females due to endocrine disruption

Radiological features of fibrous dysplasia:

-most medullary cavity lesions are lucent, loculated, or trabeculated with a thick rim of sclerosis "rind sign"

-may cause thinning of the cortex and widening of the shaft

-internal matrix is usually cloudy (ground glass appearance)

Radiological features of the skull in fibrous dysplasia:

-often areas of increased density along the convexity and anterior fossa

-unilateral overgrowth of the facial bones

-expansion in skull bones and ribs

Possible complications of fibrous dysplasia

-leg length discrepancy

-shepards crook and sabre shin deformity

-cranial nerve compromise

-protrusio acetabuli

-proptosis

-pseudoarthrosis of the tibia in infancy

-malignant transformation

-pathologic fractures