Unit 1 SG Flashcards
Aggressive = fast growing (not necessarily malignant). Key features:
Long zone of transition (ZOT)
Cortical disruption
Soft tissue involvement
Malignant (characteristics)
Laminated
Spiculated
Number of Lesions: Solitary (MC)
Ex: Simple Bone Cyst (SBC); Osteosarcoma
Number of Lesions: Multiple Lesions (Multiplicity)
Polyostotic presentation - multiple bones
Monostotic presentation - one bone
Multiplicity - multiple lesions
Ex: Metastatic Dz; multiple myeloma
Longitudinal Location: Diaphyseal Tumors (FEMALE)
Fibrous Dysplasia Eosinophilic Granuloma Myeloma Admentanoma Lymphoma (Non-Hodgkin’s) Ewings Sarcoma
Longitudinal Location: Diametaphyseal
Non-Ossifying Fibroma (NOF)
Longitudinal Location: Metaphyseal Tumors
SBC
Osteosarcoma
Longitudinal Location: Metaphyseal-Epiphyseal
Giant Cell Tumor (can grow into epiphysis but ALWAYS in metaphysis)
ABC (can grow into epiphysis)
Longitudinal Location: Epiphyseal
Chondroblastoma (only tumor that ORIGINATES in epiphysis)
Axial Location: Central
Dead center of AP and Lat
Ex: Enchondroma; SBC; Fibrous Dysplasia
Axial Location: Eccentric
MC seen overall. Central on AP and off-center on Lat; still primary in medullary cavity
Ex: Osteosarcoma; Giant Cell
Axial Location: Cortical
Overlies the cortex on AP or Lat; DDx from eccentric medullary; may overlie the medulla some, but primarily in cortex
Ex: Osteoid osteoma; Fibrous Cortical Defect (FCD)
Axial Location: Parosteal (AKA Juxtacortical)
Radiolucent cleft between tumor and cortex; mostly outside the bone but still attached to periosteum
Ex: Juxtacortical chondroma; parosteal osteosarcoma
Axial Location: Soft Tissue
Not connected to bone at all
Ex: Myositis ossificans
Skeletal Location: Skull
Osteoma
Skeletal Location: Hand
Enchondroma (MC benign tumor of hand)
Skeletal Location: Vertebra
Hemangioma (MC benign tumor of vertebra
Location: Malignant Tumors
Tend to like ANTERIOR vertebral bodies
Location: Benign Tumors
Tend to like POSTERIOR elements of vertebral bodies
Location: epidermoid Cysts (Terminal Tufts)
MC fingers and toes; result of trauma that drives epithelial tissue into bone where it continues to grow
Morphologic Features: Size
Most malignant or aggressive tumors >6cm
Morphologic Features: Margination
Can you clearly define the margins/ZOT? Is indicator of aggressiveness
Poor/wide ZOT = aggressive (aka imperceptible)
Clear/narrow ZOT - good (aka sharp); generally not malignant. Indicative of slow-growing process
Morphologic Features: Bone Destruction - Geographic
MC indicative of slow-growing lesion (least aggressive). Tends to be sharply marginated, circumscribed, uniformly lytic
Morphologic Features: Bone Destruction - Moth-Eaten
“Iffy” (usually malignancy or infection)
2-5mm in size
Outer margins poorly defined
Inner margins (moth holes) are well defined
Morphologic Features: Bone Destruction - Permeative
Most aggressive
Multiple holes <1mm
Poor ZOT
Morphologic Features: Matrix Characterization
Internal to bone, but extracellular to lesion
Morphologic Features: Matrix Characterization - Calcification
Most tumors have radiolucent matrix, SOME calcify/ossify
Dystrophic calcification: calcification due to devitalized tissue
Metastatic calcification: due to disturbance of Ca metabolism (hyperparathyroidism)
Morphologic Features: Matrix Characterization - Types (COFF)
Cartilage/Chondro
Osseous/Osteo
Fibrous/Fibro
Fat
Morphologic Features: Matrix Characterization - Types - Cartilage/Chondro
Calcified matrix; stippled, arc, ring-like, comma, popcorn
Ex: Chondrosarcoma, Enchondromas, Osteochondroma
Morphologic Features: Matrix Characterization - Types - Osseous/Osteo
Hazy, fluffy, cotton, cloud
Tumor new bone - can extend past cortex into soft tissue. Ex: Osteosarcoma
Reactive new bone - rarely extends beyond cortex. Ex: Prostatic metastasis (blastic)
Morphologic Features: Matrix Characterization - Types - Fibrous/Fibro
Ground-glass, frosted glass, smeared chalk appearance
Ex: Fibrous dysplasia
Morphologic Features: Trabeculation
Fine vs thick “soap bubbles”
Morphologic Features: Periosteal Response
Fundamental response to bone dz (bone forming irritants) that causes lifting of periosteum (blood, pus, edema, granulation tissue, neoplasm)
MC in children
2 basic patterns: Uninterrupted & Interrupted
Morphologic Features: Periosteal Response - Uninterrupted
Benign/slow-growing. Single layer of new bone
Ex: Osteoid osteoma; stress fx; hypertrophic pulmonary osteoarthopathy (HPO)
Morphologic Features: Periosteal Response - Interrupted
Laminated/Layered - “onion skin” multi-layered. Ex: Ewing’s Sarcoma
Spiculated - most aggressive. “Hair on end”/perpendicular or “sunburst”/radiating from central point. Ex: Osteosarcoma
Codman’s Triangle - aka periosteal cuff/buttress. May accompany malignant or benign tumors/infections
Morphologic Features: Soft Tissue Mass
Bone + soft tissue involvement (primary malignant tumor).
Benign tumors usually DON’T have soft tissue mass, except 4: Giant Cell; ABC; Osteoblastoma; Osteoid Osteoma
Infections MAY have soft tissue components (osteomyelitis). Generally obliterate myofacial planes and may cross joint spaces.
Tumors displace myofacial planes and DO NOT cross joint spaces
Metastatic Bone Tumors
MC osseous malignancy; usually from epithelial malignancy
Metastatic Bone Tumors: MC Primary Malignancy Sites - Male
Prostate - blastic metastasis
Lung - lytic metastasis
Metastatic Bone Tumors: MC Primary Malignancy Sites - Female
Breast - lytic and blastic metastasis
Thyroid
Kidney
Cervix
Metastatic Bone Tumors: MC Primary Malignancy Sites - Kids
<5yoa:
Neuroblastoma - lytic metastasis
Hodgkins Lymphoma - blastic metastasis
10-20yoa:
Ewing’s Sarcoma
Osteosarcoma
Metastatic Bone Tumors: Clinical Manifestations
MC 4th decade
MC presentation insidious onset, progressive, bone pain
Metastatic Bone Tumors: Laboratory
Basic bone profile to distinguish between metastasis and myeloma
ESR (erythrocyte sedimentation rate) Ca - MC w/ osteoLYTIC tumors Alk Phos - MC w/ osteoBLASTIC tumors Proteins - MC w/ multiple myeloma Uric Acid - MC w/ multiple myeloma
Metastatic Bone Tumors: Dissemination
Hematologic (MC); via Batson’s plexus in spine
Direct extension; pan-coast tumor, surgery
Metastatic Bone Tumors: Imaging Procedures
Bone Scintigraphy - procedure of choice for SCREENING b/c sensitive, cost-effective and see “whole body” simultaneously.
Works well for everything BUT Enostoma and Multiple Myeloma
Metastatic Bone Tumors: Distribution of Metastasis
From MC to LC (tumors don’t corss joints, infections do!)
Vertebra: MC metastasis go to spine (specifically VB and pedicle of T&L Spine)
Ribs & Sternum: Extrapleural sign - pushes pleura towards lungs. MC from osteoLYTIC metastasis
Skull: osteoLYTIC metastasis. MC primary breast/thyroid (holes are larger and not as well defined)
Metastatic Bone Tumors: Radiographic Features - OsteoLYTIC
MC osseous malignancy is osteolytic metastasis
Earliest radiographic manifestation, focal loss of bone density
MC cause of pedicle destruction; winking owl sign; one-eyed pedicle; blind vertebra (if both pedicles missing)
Metastatic Bone Tumors: Radiographic Features - OsteoBLASTIC
Poorly defined margins = wide ZOT
Ivory Vertebra - MC caused by:
~Osteoblastic Metastasis - VB size NOT changed; older ppl
~Paget Dz - VB INCREASES in size; older ppl
~Hodgkins - Anterior VB scalloping from enlarged lymph nodes/aorta; young ppl
Metastatic Bone Tumors: Characteristics of Metastasis vs Primary Tumor
Usually NO periosteal response
Rarely a soft tissue mass
Rarely expands bone
Metastatic Bone Tumors: Blow-Out Metastasis
LARGE lytic lesion
MC primary sites - Thyroid; Kidney
Often expansile and bubbly
Metastatic Bone Tumors: OsteoLYTIC Malignancies (FOGMACHINES)
Fibrous Dysplasia Osteoblastoma Giant Cell Metastasis/ Myeloma ABC Chondroblastoma/Chondromyxoidfibroma Hemangioma/Hyperparathyroid Infection Non-Ossifying Fibroma Enchondroma/Eosinophilic SBC
Round Cell Tumor Type (MEN)
If you see diaphysis involvement, need to think Round Cell Tumor
MEN:
~Myeloma
~Ewing’s Sarcoma
~Non-Hodgkin’s Lymphoma
Multiple Myeloma
AKA: Myeloma, Kahler’s Dz
MC primary osseous malignancy
Generalized, many lesions = multiple myeloma
Single osseous lesion = solitary plasmacytoma (much less common); ~50yoa
Multiple Myeloma: Signs/Symptoms
CARDINAL symptom is PROGRESSIVE LBP (bone pn), aggravated by exercise and weight bearing.
MC in older patients
Multiple Myeloma: Laboratory Features
Increased serum electrophoresis (most diagnostic) Normocytic/normochormic anemia Rouleaux Formation (clumping of RBC’s) Increased ESR Thrombocytopenia Increased Ca Increased Uric Acid Proteinuria (BENCE JONES proteins)
Multiple Myeloma: Locations
MC lower T&L Spine
Multiple Myeloma: Advanced Imaging & Radiographic
Bone Scintigraphy unreliable
Well-defined “punched-out” lytic lesions is key radiographic difference between MM and Osteolytic Metastasis (OLM)
Multiple Myeloma: Radiographic - Spine
Loss of bone density is EARLIEST manifestation; sharply defined end-plates that are “thin” is key indicator of VB bone loss. Males w/ osteopenic bone loss is RED FLAG!
Wrinkled vertebra = pathological collapse
Pedicle Sign: MM spares pedicles; OLM eats pedicles
Multiple Myeloma: Prognosis
MC cause of death is pneumonia
2nd MC is renal failure
Ewing’s Sarcoma
Connective tissue sarcoma in bone marrow.
4th MC primary osseous malignancy
MC <25yoa
***Mimics osteomyelitis radiographically and labs
Ewing’s Sarcoma: Signs and Symptoms
Increasing local PAIN over months; if progressive pain over days/weeks = osteomyelitis
Fever, malaise & ESR
Ewing’s Sarcoma: Location
MC primary osseous malignancy that metastasizes to bone. Metastasizes to lung also, frequent and early.
Young pt’s MC femur and tibia
>20yoa MC pelvis
Ewing’s Sarcoma: Radiographic
Laminated periosteal response, “onion-skin”
Saucerization of cortex d/t pressure from soft tissue mass; ***Easy dx of Ewing’s Sarcoma
DDx - Osteomyelitis
MC Primary Osseous Malignancies (MOCE)
Multiple Myeloma
Osteosarcoma
Chondrosarcoma
Ewing’s Sarcoma
Non-Hodgkin’s Lymphoma
AKA: Primary bone lymphoma, histocytic lymphoma, lymphosarcoma, reticulum cell sarcoma
Non-Hodgkin’s Lymphoma: Sign’s and Symptoms
25-50 yoa
MC primary osseous malignancy to initially present as pathologic fx
Non-Hodgkin’s Lymphoma: Locations
MC Femur diaphysis
Non-Hodgkin’s Lymphoma: Radiographic
NO periosteal response b/c usually older pt’s
DDx: Ewing’s Sarcoma, Paget Dz
Hodgkin’s Lymphoma
Usually metastasis from primary Systemic Hodgkin’s in chest, liver, spleen; rarely a primary bone lesion
MC initial symptom is pain, that increases w/ alcohol consumption
MC site is VB in lower T-Spine & upper L-Spine
Hodgkin’s Lymphoma: Radiographic
Ivory Vertebra; scalloping of anterior VB
MC form osteoLYTIC
MC presentation polyostotic
Exuberant periosteal response
DDx: presence of anterior VB scalloping on ivory vertebra ELIMINATES osteoBLASTIC metastasis and Paget Dz
Osteosarcoma
Both primary and secondary can metastasize.
MC form is primary, <25yoa
Secondary malignancies arise from BENIGN primary disorder, whereas metastatic dz arises from a primary MALIGNANCY
MC cause of secondary osteosarcoma is malignant degeneration of Paget Dz, 60-80yoa
Osteosarcoma: Signs and Symptoms
Bone Pain
Pyrexia (fever)
Cachexia (wasting)
Osteosarcoma: Location
MC is eccentric presentation
MC metaphysis of distal FEMUR
Anytime there are sclerotic changes w/ bone pain around the knee = osteosarcoma
Osteosarcoma: Radiographic - 3 Presentations
~MC sclerotic w/ soft tissue tumor new bone (B-day present)
~Lytic
~Mixed
Osteosarcoma: Radiographic
MC in metaphysis BEFORE epiphyseal plate closure (may travel to epiphysis after)
MC tumor new bone - radiopaque within soft tissue lesion produces cumulus cloud appearance
Osteosarcoma: Radiographic - Aggressive Periosteal Response
Sunburst is classic sign
Cannonball metastasis - looks like cannonball lesions in lungs. MC primary osseous malignancy to metastasize to LUNGS
Hair-On-End
Codman’s Triangle
Osteosarcoma: Laboratory
Alkaline phosphatase - elevated d/t tumor new bone
Parosteal Osteosarcoma
AKA: Periosteal or Juxtacortical Osteosarcoma
MC at posterior aspect of distal femur
25-40yoa
Benign Bone Tumors
4 MC painful benign bone tumors (in order): Osteoid Osteoma; Osteoblastoma; ABC; Giant Cell
(First 3 like spine, Giant cell does not)
Osteoma
Looks like enostoma; found in skull or sinuses. Enostoma’s DON’T occur in skull!
MC 15-35yoa
Gardner’s Syndrome - autosomal dominant, familial polyposis
Osteoma: Signs and Symptoms
May block ostia (opening that connects sunuses to nasal cavity) of paranasal sinuses
Osteoma: Complications
Proptosis - eyes popped out
Osteoma: Locations
MC skull, paranasal sinuses, mandible
Osteoma: Radiographic
Round or oval; well circumscribed
Osteoma: Triad
Intestinal Polyposis - almost always undergo malignant degeneration
Multiple Osteomas
Soft Tissue Tumors
Bone Islands
AKA Enostoma; small solitary foci of sense bone within spongiosa
Usually very stable
MC pelvis and proximal femur (if seen in skull = osteoma)
Metaphysis or epiphysis - NEVER diaphysis
DDx: Osteoblastic metastasis
Bone Islands: Radiographic
MC <1cm
Thorn-like radiations or brush border
Scintigraphy = NO uptake (great way to differentiate from osteoblastic metastasis - esp in older pt’s)
~Always ask for old films; if no significant change in several years = bone island
~If pt has prostate cancer, always get scintigraphy
Osteoid Osteoma
Nidus - radiolucent lesion <1cm CLASSICALLY surrounded by sclerosis (reactive new bone)
Highly vascular - usually demonstrates vascular blush on angiography
DDx: Brodies Abscess (appears identical; vascular blush in OO helps differentiate)
Osteoid Osteoma: Signs and Symptoms
10-25yoa
HALLMARK: local pain, worse at night, relieved by activity and aspirin
Focal soft tissue swelling/tenderness
Osteoid Osteoma: Locations
MC proximal femoral neck (metaphysis and diaphysis)
Vertebral arch
Osteoid Osteoma: Types
MC Intracortical - in or attached to cortex, usually accompanied w/ plenty of cortical thickening and sclerosing
Intramedullary - little sclerosing
Subperiosteal
Osteoblastoma
AKA giant osteoid osteoma
MC 10-20yoa
Osteoblastoma and osteoid osteoma are MC causes of scoliosis provoked by pn (neoplastic scoliosis)
DDx: If painful osteolytic lesion in neural arch of young pt, it’s either osteoblastoma or ABC
Osteoblastoma: Location
MC VB’s posterior arch
Osteoblastoma: Radiographic
Expansile w/ egg-shell thin cortical rim
Usually lytic
