sammy mt review

What are the 3 things we need to identify in regards to tumors?

Pain (incidental/trauma or is tumor pain inducing)

Age

Location

Two types of malignant tumors

Primary and metastatic

Main cancers that metastasize to skeleton (5)

Lung

Breast

Kidney

Colon

Bladder

Single lesion vs multiple lesions

Single lesion is most likely the primary region while multiple lesions is mostly because of METs and multiple myeloma

3 regions on long bones where tumors arise

Epiphysis

Metaphysis

Diaphysis

Other names for narrow zone of transition (4)

Geographic

Short zone of transition

Small zone of transition

Ill defined

Is cortex usually intact for narrow zone of transitions

Yes, thinning but in tact

how does the cortex usually present in wide zone of transitions

Destroyed

Narrow zone of transition means the tumor is most likely ___ while wide zone of transition means the tumor is most likely ___

Benign, malignant/aggressive

Other names for wide zone of transition (2)

Long zone of transition

Ill defined

4 location names for tumors and what they mean

Exostosis: extending off cortex

Cortical: in cortex (benign mc)

Eccentric: off center

Centralized: center of marrow

What do we mean when we say incidental finding for a tumor

Tumor is painless so patient doesn't know about it —> trauma happens —> imaging taken —> find tumor —> incidental finding

Aneurysmal bone cyst characteristics (3)

1. Named based on radiographic presentation, not what kind of cells it produces (ex: enCHONDROMA means cartilage)

2. Very expansive (hence aneurysm)

3. Super painful

Outer vs inner layer of periosteum

- outer contains blood vessels and attachment for tendons/ligamnets

- inner (cambium) is where osteoblastic/clastic activity takes place

What are the 3 aggressive periosteal reactions

Laminated/onion skin

Speculated (Sunray/Sunburst)

Codman's triangle

Which aggressive periosteal reaction is the most aggressive

Codman's triangle

Why is cod man's triangle the most aggressive

The tumor grows through the periosteum so quick that bone cant be replaced fast enough

What is ossified and gives off the sunburst appearance for spiculated periosteal reaction

Sharpey's fibers

Only benign periosteal reaction is ____

Solid

Periosteal rxns decreases after ____ ____ and is more common with primary tumors or Mets?

Skeletal maturity, primary tumors

Soft tissue masses are more common in primary tumors or Mets and WHY

Primary tumors

-Mets likes to stay where the blood is, doesn't want to move

Pattern of destruction for benign tumors (2)

1. Sharply outlined, sclerotic borders (narrow zone of transition)

2. Geographic lesion (well defined area of radiolucency)

Pattern of destruction for aggressive tumors (2)

1. Moth eaten: ragged borders (large, mult areas of radiolucency)

2. Permeative: ill defined areas through marrow (small mult areas of radiolucency)

Difference between expansile benign vs expansile malignant tumors

Benign is usually contained while malignant has a frank extension through destroyed periosteum into soft tissues

Does expansion, size and pain coming from lesion contribute to determining benign vs malignant?

No

What helps determine if tumor is benign or malignant

If the cortex is in tact or not

Terms to describe expansile tumors (4)

Bubbly

Trabeculated

Loculated

Chambered

T/F tumors that contain "chondro-" will eventually calcify

True

Enchondroma is the mc tumor of...

The hands and feet

Plasmacytoma is mc found where

The clavicle

What 3 things help differentially diagnose tumors

Age, pain, location

MC malignant tumor of skeleton is...

Mets (70%)

Most Mets occur after age of

40

Mets in 5 year olds or younger is...

Neuroblastomoa

Mets in 10-20 age group is (2)

Ewing's sarcoma and osteosarcoma

Mets in 20 year olds and over is...

Hodgkin's lymphoma

Mets more common in males or females

Males

Why are pathological fractures common in Mets patients

Bone weakens when cancer cells infiltrate

MC cancer to produce blastic Mets in males is

Prostate

MC cancer to produce lytic Mets in males is

Lung

MC cancer to produce both lytic and blastic Mets in females is

Breast

Do we see fast or delayed onset from primary for Mets

Delayed

3 routes of extension for Mets and which is most common

Direct extension

Lymphatic channels

Hematogenous dissemination (MC)

Hematogenous dissemination def

Tumor cells from primary site will break off and float in blood stream and deposit in some other site (Batson venous plexus)

Blastic or lytic Mets more common

Lytic (75%)

Lytic Mets def

Destruction exceeds repair and radiolucent areas appear as holes in bone (moth eaten/permeative)

Lytic Mets has what kind of prognosis

Poor

Why do lytic lesions happen in lytic Mets

Occur as result of pressure erosions form medullary tumor and parathyroid hormone stimulates osteoclasts

Blastic Mets def

Tumor cells replace bone at a rate that allows the body to wall off tumor cells with new bone around cancer cells (slow growing)

Prognosis for blastic Mets

Better than lytic

What xray appearance do we see with blastic Mets

Multiple snowball appearance (sclerotic)

What do we need to ddx blastic Mets with

Pagets (has diffuse whitening on xray), blastic Mets has more outlined "snowballs"

DONUT QUESTION: 3 conditions that lead to ivory vertebra

Blastic Mets

Pagets

Hodgkin lymphoma

Blowout Mets appearance

Bubbly and expansile

What do we ddx blowout Mets with

Solitary plasmocytoma and giant cell tumor

Blowout Mets most commonly comes from carcinoma of the...(3)

Lung, thyroid and kidney (the aggressive cancers)

What age group do we see blowout Mets

45 years and up

Primary malignancies vs Mets characteristics

-primary is solitary lesion while Mets is multiple lesions

-primary are usually bigger and Mets is smaller

-primary has expansion of bone

-primary has periosteal reactions

-primary has soft tissue mass

What is the exception when distinguishing primary malignancies from Mets?

Blowout Mets

Gold standard for diagnosing primary cell type

Biopsy

What will labs show for blastic Mets

High alkaline phosphates

What will labs show for lytic Mets

High serum calcium

How much % of bone loss is needed before it is detected on xray

30-50%

Why is CT not as good as MRI when it comes to tumors

It's more sensitive than xray, but may overlook subtle areas of marrow replacement

Is a bone scan the same thing as DEXA scan?

NO

What is injected into the pt for bone scans (contrast agent)

Technetium-99m

What are the darker spots on bone scans called and what do they represent

Hot spots, show accumulation of tech-99 in areas of high metabolism

Bone scans are the gold standard for evaluating entire skeleton for ___ ___

Multiple lesions (polyostotic)

3 phases of bone scan

Flow phase

Pool phase

Bone phase

3 characteristics of hypertrophic periarthopathy (she said in lecture idk if she'll test"

1. Diaphyseal periostitis

2. Clubbing of nails

3. Joint pain in knees and hips

check chest and ribs

MRI detects up to ___% of skeletal Mets

91%

What is the contrast medium used in MRI

Gadolinium

T1 MRI is sensitive to ___ and T2 MRI is sensitive to ___

Fat, fluid

On T1 MRI, is marrow brighter or darker than CSF

Brighter (more fat)

On T2 MRI, is marrow brighter or darker than CSF

Darker (less fluid compared to CSF)

If we see Mets in marrow on T1 MRI, will it be darker or lighter

Darker

If we see Mets in marrow on a T2 MRI, will it be darker or lighter

Lighter

Where is Mets most common in skeleton, where is it the least common?

MC = axial spine

LC = proximal long bones

Acral metastasis location, how common it is, and is MC due to which primary cancers

-Distal to elbow and knee

-Rare

-lung, breast and kidney

Acral Mets and blowout Mets come from ___ primary tumors

Aggressive (lung, kidney breast, thyroid)

Earliest sign of lytic Mets in vertebral body

Subtle loss of density in contrast to adjacent bodies

Lytic Mets in vertebral body may result in which type of fracture

Compression (both anterior and poster body)

Mc causes of universal compression fx (3)

Osteoporosis

Mets

Multiple myeloma

Neoplastic weakening and destruction of endplates may lead to what

Schmorl's nodes (intrabody disc herniation)

Mets and multiple myeloma may involve multiple vertebral segments, how do we ddx them then?

Labs

Top 3 causes of ivory vertebra in order of most common to least common

Osteoblastic Mets

Pagets

Hodgkin's lymphoma

How does ivory vertebra present in osteoblastic Mets

Normal size and shape with normal anterior body

How does ivory vertebra present in pagets (3)

1. Enlarged vertebral body (cortical thickening)

2. Squaring off of ant body (picture frame)

3. Bone softening —> compression fx

How does ivory vertebra present in Hodgkin's lymphoma and what xray view do you see it in

Anterior scalloping of vertebral body on lateral xray

How does anterior scalloping of body develop in Hodgkin's lymphoma

Lymph node enlargement puts pressure onto vertebral body —> anterior scalloping (pressure erosion) —> continues into adjacent vertebra

How to ddx Hodgkin's lymphoma with pagets and osteoblastic Mets

Age! Hodgkin's usually in 20-40 years old while pagets and Mets is over 40 years old

Pedicle destruction in Mets is best seen on what xray view, what name sign do we see?

AP view, winking/blind owl sign

Is pedicle destruction more common in Mets or multiple myeloma and why

Mets due to the batson venous plexus being right behind vertebral body (where pedicle is).

-Mets travels to vertebra (thru blood) while multiple myeloma starts in vertebra (where plasma cells are concentrated most —> center of vertebral body, which isn't as close to pedicle)

Pedicle destruction in Mets mc where in the spine

Lower thoracic and lumbar spine

What do we ddx winking owl sign with (2)

1. Congenital agenesis (stress hypertrophy of opposite pedicle)

2. Destruction of pedicle from ABC or osteoblastoma

What do we also see disappear with winking owl sign (2)

Transverse process and posterior vertebral body

Pelvis is a target for Mets due to

Seeding from viscera via batson venous plexus

Are blowout lesions common in the pelvis

Yes

Why is it hard to ddx blastic Mets with pagets in the pelvis

Occasionally blastic lesion may exhibit osseous expansion

What appearance do we see on xray with blastic Mets usually

Snowball appearance