MIDTERM TUMOR* Flashcards
What are common sites of neoplasms?
FEMUR, pelvis, humerus
(UNCOMMON in spine)
Osteosarcom neoplasm %
50-55%
Fibrosarcoma neoplasm %
20-25%
Chondrosarcoma neoplasm %
10%
What is a neoplasm?
Abnormal cellular growth that can be benign or malignant
- Malignant: Ability to metastasize/spread
- Benign: Does not metastasize, but this does not mean insignificant
Any cell found in bone can produce ______
a tumor
* Subdivided by what type of cell it comes from
If a tumor originates in bone it is called a _____
primary bone tumor
What is a secondary bone tumor basic definition?
Starts somewhere else and metastasizes to bone
What is a tumor like lesion?
Lesions that radiographically appear as tumors but are not histo-pathologically classified as a tumor - usually produce geographic radiolucency

Primary bone tumors, benign category:
- Osteoma - MOST COMMON, intramembranous bone tumor, dont hurt
- Osteoid Osteoma - not as common, HURT
- Osteoblastoma - RARE, but half occur in spine

Describe conventional osteosarcomas:
Most of these are central sclerotic (about 75%) originate from inside the bone and loves the distal femoral metaphysis
- 72% (over 2/3 of all osteosarcomas)

What is multifocal Osteosarcomatosis?
Most often in children in first decade, nearly always fatal

Osteosarcoma can be from post therapeutic radiation, t/f
true

What type of malignant bone tumor is extremely vascular?
Telangiectatic

What type of tumor can become an ostoesarcoma?
Dedifferentiated chondrosarcoma

What osteosarcoma originates in the soft tissue attached to the bone?
Extraskeletal Osteosarcoma
What is a tumor of the cortical bone?
Chondroma, and it is a common benign

What is a benign bone tumor that is inside the bone?
Enchondroma

Is osteochondroma benign or malignant?
Benign

What is a fibromyxoid chondroma?
Tumor made of fibrous mucus cartilage
- Dominant content is cartilage
- Loves the TIBIA - rare to be anywhere else
BENIGN

What is a chondroblastoma?
High concentration found in the epiphysis - where chondroblasts are located - may spread into rest of bone
BENIGN**

What are the 3 Malignant cartilage Tumors?
- Primary Chondrosarcoma
- Secondary Chondrosarcoma
- Clear cell chondrosarcoma

What is primary chondrosarcoma?
Didn’t require anything else for it to be there, it originates by itself

What is secondary chondrosarcoma?
From a preexisting benign tumor that malignantly degenerate - can be multiple
- Central secondary chondrosarcoma - From ENCHONDROMA, central is inside the bone in medullary cavity or cortex
- Peripheral - OSTEOCHONDROMA - located external to the bone, looks like a trunk/stalk of broccoli coming off

Malignant bone tumr =
Osteosarcoma
Peripheral secondary chondrosarcoma comes from _____ ?
Osteochondroma

What is clear cell chondrosarcoma?
Usually near a joint, mistaken for chondroblastoma

What is one of the more common bone tumors?
Giant cell tumor of bone/osteoclastoma

What are the characteristics of Giant cell tumor?
- Classically expansile soap bubble lesion
- about 1 in 5 are malignant
- “Quasi - malignant” can go either way - 80% malignant

Where do giant cell tumors most likey occur?
At the knee (HURT)

Ewings Sarcoma is in what category?
Marrow tumor (round cell tumor)
- Classically gives laminated periosteal reaction
- moth eaten appearance
- big tubular bone in young children

What is the most common primary bone malignancy in first decade (peak in teenagers)?
EWINGS SARCOMA
- dont confuse Leukemia, which is the most common malignancy in the first decade

What category is Non-Hodgkin Lymphoma under? (NHL)
Marrow tumor (round cell tumor: malignant)

What is the most common primary bone malignancy?
_Multiple Myeloma**** TEST_

Where would you see true punched out lesions?
Multiple Myeloma

Explain Myelomatosis:
Form of multiple myeloma:
- Produces osteopenia, looks like osteoporosis - will also have weakness and fatigue due to anemia - radiographically will look the same

What will plasmacytoma have?
Geographic soap bubble lesion

What is “extra osseous” ?
Branch of multiple myeloma
- Mass in nasal pharynx (difficulty breathing), very uncommon

What is under the Benign Vascular and Connective Tissue tumor?
Hemangioma - produces localized coarsening of the trabecular pattern

What is the “Malignant vascular tumor?’
Fibrosarcoma

What is the notochord remnant tumor?
Chordoma - most often found in Clivus, C2, sacro-coccygeal, will cross the joint

What are the key points of osteolytic mets?
- Destroys by physical bulk and restricting osteoblasts
- 80% of metastasis found in spine, ribs and pelvis with another 10% found in cranium
- Rarely go beyond the elbow and knee
What accelerates osteoblasts?
Osteoblastic mets

Pic of mixed mets
What are 2 of the most common benign bone tumors?
Chondroma and Solitary Osteochondroma - asymptomatic
How can tumors be classified?
- They can be classified by location of where they originate - most often from the metaphysis

What are the top “Malignant Tumors” ?
MOCEF - top 5 primary malignant
- Multiple Myeloma: Over 40
- Osteosarcoma: under 30
- Chondrosarcoma: 40 - 60
- Ewing’s: Under 40
- Fibrosarcoma: 30 - 60

Central secondary chondrosarcoma comes from _____
Enchondroma
Marrow tumors, aka:
round cell tumors
What is the common theme with marrow tumors (round cell tumors)?
_Occur in diaphysis and are all MALGINANT AND DESTRUCTIVE ******_
What are secondary tumors?
Metastatic tumors in bone
Vast majority of secondary tumors are _____
Hematogenous
Osteolytic mets is a _____
secondary tumor
What has 75% occurence %, osteolytic mets or osteoblastic mets?
Osteolytic
What is in the “Tumor Like” category?
- Not exhaustive list
- Fibrous dysplasia - as common as Paget’s
If a tumor is most likely benign, what will it’s characteristics be?
- Almost always originate before age of 30 (with exception of giant cell tumor 20-40 years old)
KNOW THIS***
Primary Bone Tumors:
- Bone Forming Tumors
- Cartilage Forming Tumors
- Giant Cell Tumor of Bone/Osteoclastoma
- Marrow Tumors (Round Cell Tumors)
- Vascular and Connective Tissue Tumors
- Notochord Remnant Tumor
What are the Bone forming primary bone tumors?
-
Benign
- Osteoma
- Osteoid Osteoma
- Osteoblastoma
-
Malignant - Osteosarcomas
- Conventional Osteosarcoma
- 72% central
- 75% sclerotic
- 25% lytic
- Parosteal Os 4%
- Periosteal Os 1%
- Multifocal Os/osteosarcomatosis 1%
- Osteosarcoma of Jaw - 6%
- Post Radiation Os - 4%
- Os in Paget’s disease - 3%
- Os Degeneration from benign condition - 1%
- Telangiectatic Os - 3%
- Dedifferentiated Chondrosarcoma - 3%
- Extraskeletal Os. < 1%
- Conventional Osteosarcoma
What are the Benign Cartilage Forming Tumors?
- Benign
- Chodnroma/Enchondroma
- Solitary Osteochondroma
- Chondromyxoid Fibroma/Fibromyxoid Chondroma
- Chondroblastoma
What are the malignant Cartilage forming tumors?
Malignant
- Primary Chondrosarcoma - arise de novo
- Secondary Chondrosarcoma - from preexisting benign tumor
- Central - From enchondroma
- Peripheral - From Osteochondroma
- Clear cell chondrosarcoma - mistaken form chondroblastoma, low grade
- Extra Skeletal - Rare
What are the marrow tumors (round cell tumors?)
- Ewing’s Sarcoma
- NHL (non hodgkin lymphoma) of bone/reticulum cell sarcoma
- Multiple Myeloma
What are the branches of multiple myeloma?
- Classical MM
- Myelomatosis
- Plasmacytoma
- Extra Osseous MM
Vascular and Connective Tissue tumors are in what category, what are their subcategories?
It is in the category of “primary bone tumor”
- Benign - Hemangioma
- Malignant - Fibrosarcoma
Metastatic Tumors in bone - most common skeletal malginancy
- Osteolytic Mets
- Osteoblastic Mets
- Mixed Mets
Tumor Like Conditions:
PRIMARY BONE TUMORS
- Solitary bone cyst/Unicameral bone cyst
- Aneurysmal bone cyst
- Fibrous Cortical defect and nonossifying fibroma
- Fibrous Dysplasia
- Brown Tumor of hyperparathyroidism
- Pseudotumors of Hemophilia
- Large Arthritic Cysts/Geode
If it’s a benign tumor they overwhelmingly originate when?
Before the Age of 30
If a tumor is asymptomatic and benign, it may not show till ____
age 50
When does Giant cell tumor usually occur?
20-40 this is an exception
Metastisis happens how?
Through Vascular system
Big 6 strongest potential to spread?
- Breast - females 70%
- Lung - 25%
- Prostate - Males 60%
- Kidney
- Ewing’s
- Neuroblastoma
*** Breast, lung, prostate, and kidney account for 80%
Where does lytic Mets come from?
Physical bulk - pressure from the tumor taking up space which impedes the osteoblasts
- More common (75% of metastasis destroys)
Approximately 80% of all osseous metastases will be found _____
In the axial skeleton
- 28% ribs
- 39% vertebra
- 13% bony pelvis
10 % of skeletal metastasis will be found in the cranium
10% extremities
Is Enostosis primary or secondary bone tumor?
Primary
AKA BONE ISLAND
What is enostosis classified as?
Tumorlike, usually an incidental finding, and is asymptomatic
What are the characteristics of Enostosis?
- Rare in children
- Osteosclerotic bone lesion
- Can be considered a hamartoma (benign tumor that is multicellular and has all the cells of the host tissue)
Where is the location of Enostosis?
Intramedullary Location - usually up against inner surface of cortex
- Composed of normal appearing compact lamellar bone with haversian canals
- Blends with surround trabecular bone creating irregular margin
What is the radiological appearance of Enostosis
- Round to oval (.2 - 2 cm) osteoblastic area
- Epiphyseal or metaphyseal
- Bone scan NORMAL
95 % no need for further radiologic evaluation
WHat is the differential diagnosis for Enostosis?
Osteoblastic Mets, osteoma, osteoid osteoma, low grade osteosarcoma
Osteoblastic mets ____
HURTS
low grade osteosarcoma is ____
PAINFUL
When would you take a biopsy of Enostosis?
Increase in size of 25% in 6 months
Bony pelivs is a common site to see ____
enostosis
Giant bone island is a _____
Enostosis that is > 2-3 cm in size
More likely to have increased activity on bone scan
What are the possible diseases related to Enostosis?
- Osteopoikilosis
- Osteopathia Striata
- Melorheostosis
Osteopoikilosis =
Periarticular bone islands
Osteopathia Striata =
Lesions are more elongated in periarticular pattern, Vooerheve disease, fan-like bands in flat bones
What are the 3 common characteristics of Melorheostosis?
- Osteosclerotic bone disorder
- Often symptomatic (pain, decreased ROM, contractures, limb swelling, bowing)
- Scleroderma - like skin lesions over osseous changes
What is the radiology of Melorheostosis?
o Osseous excrescences often exuberant and lobulated along bone surface
o Single limb—more common lower extremity
o Also endosteal involvement may extend into marrow space
o Intense activity on bone scan
o Long drippy bone island
Benign Bone forming:
OSTEOMA
OSTEOID OSTEOMA
OSTEOBLASTOMA
Osteoma aka:
Ivory Exostosis
What is a benign, slow growing hamartomatous lesion composed of well differentiated mature bone?
Osteoma
What is the defect in Osteoma?
One resorption or formation during skeletal maturation
What does osteoma arises beneath?
Endosteum from inner surface of cortex
What causes surrounding reactive bone formation in Osteomas?
Elevation of periosteum from underlying bone
Osteoma is a bone of _____
Intramembranous origin
Extracranial Osteoms -
.03% of bone biopsied primary bone lesions
Paranasal sinus osteomas -
.4%
Most have a osteosclerotic lesion in a frontal or ethmoid lesion
What are the associated abnormailities with Osteoma?
- Gardner’s Syndrome
- Mutation of Adenmatous Polyposis Coli Gene (5q21)
- Multiple osteomas, intestinal polypsos, soft tissue desmoid tumors
- Bone lesions may precede intestinal polyposis
Describe Gardner’s Syndrome in Osteoma:
- Autosomal Dominant
- Syndrome of hamartomatous tumors in different locations
- One of the key findings - osteomas
- Will develop color cancer (precursor to colon cancer)
In osteoma, most just have ____
single solitary osteoma
What are the clinical issues associated with Osteoma?
- Small lesions usually asymptomatic
- Project away from cortical surface
- Palpable enlarging osseous mass
What is the nasal issue with Osteoma?
- Large oseomain paranasal sinus may obstruct nasal ducts
- Can erode wall of cranial fossa and dura
- Can cause mucocele, sinusitis, headache, pain
What can osteoma tumors near orbit cause?
Cause exopthalmosis, double vision, vision loss
What about the Hx of Osteoma:
- Found before 30 but can be seen anytime
- EQUAL GENDER
- No malginant potential
What looks identical to bone island but has different location?
Osteoma
What does Osteoma look like radiographically?
(first 3)
- Well defined round dense sclerotic lesion attach to underlying bone
- Vast majority in frontal and ethmoid sinus
- DENSE ivory like sclerotic mass
What does Osteoma look like radiographically?
(last 3)
- No satellite lesions
- Low signal on MRI
- Plain film is good to see them
OSTEOID OSTEOMA: main characteristics
- Painful!
- Produce dense periosteal reaction
- Can regress spontaneously - infarction
- Local swelling and point tenderness
What is Osteoid Osteoma characterized by?
Nidus less than 1 cm of osteoid/woven bone is vascular tissue surrounded by zone of reactive sclerosis
What is elevated in Osteoid Osteoma?
Prostaglandin E2 elevated 100-1000 times within Nidus (pain and vasodilation)
Describe the nidus in Osteoid osteoma:
Radiolucent and is the actual tumor
Pain is worse at night with what tumor?
Osteoid Osteoma
Whats the origin of Osteoid Osteoma?
Unknown, inflammatory, traumatic, vascular, viral
What is a distinguishing characteristic of Osteoid Osteoma?
These can produce a painful scoliosis, and they happen in the spine (lean into a legion)
Osteoid Osteoma is more common in ______
males 2-3:1
What are the first 4 radiological features of Osteoid Osteoma?
- Long bones are common
- Metaphysis/Diaphysis
- Phalanges of hands and feet
- Spine (10%)
- Posterior Elements 90% - posterior arch lamina
- Vertebral body 10%
What are the last 5-6 radiological features of osteoid osteoma?
- Cortical: 70-80%
- Radiolucent Nidus < 1.5 cm with surrounding dense sclerosis
- Periosteal reaction may be present
- Medullary: 25%
- CT - well defined, round oval nidus surrounded by sclerosis
- MRI - T1 WI nidus isointense to muscle
What does osteoid osteoma look like on bone scan?
lights up
(will have a solid dense periosteal reaction)
OSTEOBLASTOMA aka:
Giant osteoid osteoma, osteogenic fibroma
What is Osteoblastoma characterized by?
- Production of osteoid and woven bone
- Lesion > 1.5 cm
- Histology similar to osteoid osteoma
What are the %’s associated with Osteoblastoma?
< 1% of primary bone tumors
3% benign bone tumor
Describe Osteoblastoma:
- Circumscribed mass, often surrounded by shell of cortical bone or periosteum
- Sharp interphase between lesion and cancellous bone
What does the nidus look like in Osteoblastoma?
- 2-10 cm, friable, deep red (highly vascular)
- Very vascular connective tissue stroma with interconnecting trabecular bone
What are the symptoms of osteoblastoma?
- Dull, localized pain of insidious onset
- Pain rarely interferes with sleep
- Localized swelling, tenderness, and decreased ROM
- Doesnt respond well to aspirin
Osteoblastoma originates ____
under 30
Osteoblastoma gender pref.
2-3:1 in males
WHat can Ostoeblastoma have?
Foci of aggressive stage 3 lesion (prone to aneurysmal bone cysts formation)
RECURRENCE AFTER resection = 10-25%
In aggressive osteoblastoma, the recurrence is ____ %
50
First 4 things of Osteoblastoma (radiology):
- 30-50% SPINAL
- Posterior elements –> 60% spinous, transverse process, pedicle
- Posterior elements with extension into vertebral body 25%
- Vertebral body 15%
- Long bones, 30% originate in metaphysis
What are the 5-8 radiographic features of Osteoblastoma?
- Hands and feet 15%
- Skull and Jaw 15%
- Pelvis 5%
- Expansile, lytic circumscribed lesion
- Reactive sclerosis 60%
Last radiologic features of Osteoblastoma:
- CAN rapidly increase in size
- Secondary aneurysmal bone cyst (ABC): 16% can look exactly the same
- NECT: Expansile, lytic lesion with or without matrix mineralization
- Can be purely radiolucent inside, speckled (inside matrix), or sclerotic looking
KEY IS EXPANSION
MALIGNANT PRIMARY BONE TUMORS:
Osteosarcoma, aka Osteogenic Osteosarcoma
What is the main definition of Osteosarcoma?
Malignant tumor with ability to produce osteoid directly from neoplastic cells
Talk about the growth rate of Osteosarcoma:
Frequency of tumor occurence corresponds to greatest growth rate during adolescence
What is chemically happening in osteosarcoma?
Overexpression of P-glycogen in OGS cells with propensity for metastasis and rx failure
alteration in Rb genes in OGS
Think of osteosarcoma as ____
osteoblastic malignant tumor
Periosteal reaction of osteosarcoma =
Spiculated
2nd primary bone tumor is ____
Osteosarcoma (MOCEF)
When does osteosarcoma peak?
teens
Where is the most common location for osteosarcoma?
Distal femoral metaphysis
Osteosarcomatosis survival:
Change low
Where will osteosarcoma metastasize to?
LUNG
Osteosarcoma has a majority of unknown origin, primary, but secondary to predisposing factors are:
- Paget’s Disease (4th stage)
- Bone infarction
- Radiation
What is the most common malignant primary bone tumor in young adults and children?
Osteosarcoma
20% primary bone malignancies:
Osteosarcoma
What is a heterogenous mass with ossified and non ossified components?
Osteosarcoma
What are the symptoms of Osteosarcoma?
- Progressive Pain
- Soft tissue mass, swelling
- Pathological fracture
- Penetration of cortex with often large extraosseous tumor mass
What is common with Osteosarcoma?
Pulmonary mets common - pneumothorax
What is most common location of osteosarcoma?
Femur #1 big tubular bone - distal femoral metaphysis is most common
What is increased in osteosarcoma?
Serum Alkaline Phosphatase
Alkaline phosphatase is produced by osteoblasts
Age in Osteosarcoma:
- Bimodal
- First peak 2-3 decade
- Second peak - 6th decade
- Usually happens from paget disease undergoing malignant degeneration
What is the Gender in Osteosarcoma?
- Male:Female - 1.3-1.6: 1
- More common in Black people
- Very progressive
- 5 year survival = 41%
- 5 year with resectable tumor and no mets = 60-70%
What are the first 3 “Radiology location” signs for Osteosarcoma?
- Around knee - 55%
- Metaphysis of long tubular bones - 80%
- Extenison into epiphysis - 75%
- Pushes itself across the growth plate into the epiphysis
- no vascular connection
What are the last few radiographic features of Osteosarcoma?
- Flat bones, VB 20%
- In older patient (>50) axial skeleton and flat bones 40%
- size 5-10 cm
What are the first few points of Conventional Osteosarcoma (2nd type)?
- Poorly defined, intramedullary mass, extends through cortex
- Moth eaten bone destruction
What are the last points of Conventional Osteosarcoma (2nd type)?
- Aggressive Periosteal Reaction
- Codman triangle
- Sunburst (speculated) pattern
- Indistinct borders with WZOT wide zone
- Soft tissue mass +/- tumor calcification
What are the radiographic appearances of Telangiectatic Osteosarcoma?
- Purely lytic lesion
- Cystic cavities filled with blood, necrosis
- Fluid levels
What are the radiographic findings of Multicentric Osteosarcoma?
o Synchronous osteoblastic osteosarcoma at multiple sites
o Basically same as central sclerotic but happening at multiple locations
o Exclusively in children (5-10 years)
o Extremely poor prognosis
Parosteal Osteosarcoma Radiographic features:
o Low grade osteosarcoma in older age group (20-50 years)
o Posterior distal femur
o Attached to underlying cortex at origin
o Originates from cortex and grows out into soft tissue
o Can look like a mushroom
o Dense bony look to them
Radiographic features of Periosteal Osteosarcoma:
first 4
o Intermediate grade osteosarcoma
o Most common diaphyseal
o No medullary involvement
o Cortical thickening
Last 4 radiographic features of Periosteal Osteosarcoma:
o Sandwiched between periosteum and the cortex
o Doesn’t usually invade the cortex
o May even cause cortical erosion
o Speckled appearance
What are the radiographic features of Gnathic Osteosarcoma?
o Involvement of mandible, maxilla
o Sclerotic, lytic, mixed
o Periosteal reaction
o Soft tissue extension
What are the key radiographic features of Secondary Osteosarcoma?
Arises in pre existing bone lesion
o About half of osteosarcoma over age 50 are secondary, 67^ over age 60
▪ Paget disease
▪ Prior radiation
▪ Bone infarction
▪ Fibrous dysplasia
▪ Prosthesis
▪ OI
▪ Chronic osteomyelitis
▪ Retinoblastoma
Osteosarcoma does what on a bone scan?
lights up
If osteosarcoma hasn’t metastisized, what can you do?
Amputate and this will have a good prognossis
What is a bone generating bone tumor?
Osteosarcoma