Bone Tumors Flashcards
Malignant bone tumors comprise __% of all types of cancer
Malignant bone tumors comprise **~0.2% **of all types of cancer
What are potential clinical presentations for bone tumor?
-
Pain
- any tumor
- osteoid osteoma: severe pain, worse at night, relieved by aspirin
-
Mass
- parosteal OS: painless, hard growing mass in popliteal fossa
- Pathologic fracture
- Asymptomatic
What are some diagnostic factors to consider for bone tumors?
- Age
- Sex
- Skeletal localization
- Specific bone
- Specific area of bone
- Medullary cavity, cortex, juxtacortical
- Epiphysis, metaphysis, diaphysis
- Radiographic appearance
How does age correlate with the following tumors?
- Osteosarcoma, Ewing’s sarcoma ⇒
- Giant cell tumor ⇒
- Chondrosarcoma ⇒
- Osteosarcoma, Ewing’s sarcoma ⇒ childhood, adolescence
- Giant cell tumor ⇒ young adults
- Chondrosarcoma ⇒ elderly
- Sclerotic margin is generally an indication of:
- Ill-defined margin is generally an indication of:
- Solid, ivory-like pattern is generally seen in:
- Rings and arcs are generally seen in:
-
Sclerotic margin is generally an indication of:
- benign, slowly-growing neoplasm
-
Ill-defined margin is generally an indication of:
- malignant, rapidly-growing neoplasm
-
Solid, ivory-like pattern is generally seen in:
- malignant bone matrix-forming tumors
-
Rings and arcs are generally seen in:
- chondroid matrix-forming tumors
What are characteristics of osteiod osteoma?
- Long bones, femur & tibia
- < 2 cm
- Night pain
- Responds to aspirin
- Radiolucent lesion within sclerotic cortex
What are the characteristics of osteoblastomas?
- Vertebrae or long bone metaphysis
- > 2 cm
- Painful
- Not responsive to aspirin
- Expansile radio-lucency with mottling
What is the most common sarcoma of bone?
osteosarcoma
What kind tumor is osteosarcoma?
Malignant mesenchymal tumor in which cells produce osteoid or bone
Where does an osteosarcoma typically present? Where does it typically spread?
-
Metaphysis of long bones
- Femur, tibia, humerus (56%); flat bones, spine (older patients)
- May be polyostotic (not common)
-
Hematogenous spread to lungs is common
- Also mets to pleura, other bones & CNS
Describe the posssible pathogenesis of osteosarcoma:
-
Inherited mutant allele of RB gene
- Hereditary RB: marked increase (1000X) in OS
-
Mutation of p53 suppressor gene
- Li-Fraumeni: bone and soft tissue sarcomas, early onset breast cancer, brain tumors, leukemia
- Overexpression of MDM2 (5-10%); INK4 and p16
- Sites of bone growth/disease (i.e. Paget dz.)
- Prior irradiation
What are the morphologic features of osteosarcoma?
- Poorly delineated
- Bone destruction
- Cortical disruption
- Bone matrix
- Soft tissue extension
- Codman’s triangle
Osteosarcoma
- Pathology:
- Treatment:
- Pathology:
- Infiltrative tumor, extending into soft tissue
- Malignant cells producing osteoid
- Treatment:
- Neo-adjuvant chemotherapy and surgical resection
Osteosarcoma: Prognosis
- Post chemotherapy: 60-65% 3-5 yr. survival for patients with non-metastatic disease
- En-bloc resection following chemotherapy: >90% necrosis ⇒ near 90% survival
What is the most common benign tumor of bone?
osteochondroma
Where does an osteochondroma typically present? What is the genetic alteration associated with this tumor?
- Metaphysis of long bones
- Malignant transformation is rare (<1%), but increased risk (~40%) in hereditary multiple exostoses (multiple osteochondromas)
- Autosomal dominant, most commonly secondary to mutations in EXT-1 (8q24)
What is an enchondroma? What is a perisoteal chondroma?
Benign hyaline cartilage lesion
- Enchondroma = intramedullary chondroma
-
Periosteal chondroma = juxtacortical chondroma
- located on the cortical surface under the periosteum
Describe the characteristics associated with an enchondroma.
- How does it appear on x-ray?
- How does it appear microscopically?
- How is it treated?
- Usually asymptomatic, incidental finding
-
Appendicular skeleton
- __small bones of hands and feet
- X-Rays: Lytic, lobulated, cortical thinning
- Micro: lobules of hyaline cartilage, minimal atypia
-
Treatment: none, unless lesion shows changes:
- Symptomatic (onset of acute pain is felt to be circumstantial evidence that lesion is malignant)
- Evidence of recent growth after skeletal maturity
What can cause multiple chondromatosis? What are the types of multiple chondromatosis?
Frequent point mutations in IDH1 or IDH2
-
Ollier’s disease
- Multiple enchondromata
- Tend to have regional distribution
- ± severe skeletal malformation
-
Maffucci’s syndrome
- Multiple enchondromata + angiomata
- Severe skeletal malformation
- Higher incidence of malignant transformation
What is the second most common bone sarcoma?
What age group does usually present in?
Where does it typically present?
Chondrosarcoma
- Malignant tumor in which neoplastic cells produce a purely cartilaginous matrix
- ~26% of all bone sarcomas
- Wide range of ages, mainly older adults
- Mostly above 40-50 years
- Peak during 6th- 7th decades
- Central skeleton: pelvis and ribs (45%); humerus, femur (metaphysis, diaphysis)
What would be seen on imaging for a chondrosarcoma?
- Medullary location
- Frequently present calcifications, which tend to be lost in grade 3 tumors
- Cortical erosion or destruction
- Occasional soft tissue extension
- “popcorn-like” appearance
What pathology is associated chondrosarcoma?
How is the size of the tumor important?
What is the grade based upon?
- Generally more cellular and nuclei more pleomorphic than in enchondromas
- Binucleation is frequent, but does not suffice for malignant diagnosis
- Myxoid change of chondroid matrix
- Size (< or > 10 cm) and grade correlate with behavior
- Grading (1-3) based on degree of cellularity and atypia
What is the 5 year survival rate for chondrosarcoma? What are the variants of chondrosarcoma?
-
5 year survival:
- Grades 1,2: 80-90%
- Grade 3: 29% (pulmonary metastasis)
-
Variants:
- de-differentiated
- myxoid
- clear cell
- mesenchymal
- juxtacortical
Non-ossifying fibroma:
- Cause:
- Presentation:
-
Cause:
- Common developmental cortical defect
-
Presentation:
- Tibia, femur (metaphysis); 1st – 3rd decades.
- Eccentric, lytic, peripheral sclerosis
- Incidental finding or pathologic fracture
Fibrous Dysplasia:
- Monostotic
- Polyostotic
Developmental arrest of bone
-
Monostotic
- Most common, seen in adolescents
- Ribs, mandible and femur
-
Polyostotic
- Infancy/childhood
- Crippling deformities, craniofacial involvement common
What is McCune-Albright syndrome?
-
Polyostotic FD with endocrinopathies and café-au-lait spots
- Rare form; F>M
- Sexual precocity, acromegaly, Cushing syndrome
- Activating germline mutations of GNAS (GTP-binding protein) result in excess cAMP leading to endocrine gland hyperfunction
What are the morphologic features of fibrous dysplasia?
- Expansile
- Circumscribed
- Thinned cortex
- “Ground glass”
- May be multiple
Fibrous Dysplasia:
- Pathology
- Treatment
-
Pathology
- Haphazard, curvilinear, randomly oriented woven bone trabeculae (“Chinese characters”), surrounded by fibroblastic stroma
- No significant osteoblastic rimming
-
Treatment
- Conservative, except polyostotic form
What is the second most common malignant bone tumor in childhood?
Ewing Sarcoma/PNET
How does Ewing sarcoma/PNET typically present?
- Adolescents, young adults
- M>F
- Present as painful, often enlarging mass
- Diaphysis of long tubular bones, ribs and pelvis
How does Ewing sarcoma/PNET appear on X-ray?
-
X-RAY:
- Destructive moth-eaten, permeative medullary lesion with large soft tissue mass
- “Onion-skin” pattern of periosteal reaction in response to rapid growth
Ewing sarcoma/PNET:
Pathology
- Sheets of primitive small round blue cells with neural phenotype
- Membranous CD99
- t(11;22)(q24;q12)
- Contain abundant glycogen
- Hemorrhage and necrosis common
Ewing sarcoma/PNET:
- Pathogenesis
- Treatment
-
Pathogenesis:
- EWS involved in >95% of ES/PNET
- t(11;22) present in 85% of the tumors
- EWS on 22q fused with FLI-1 transcription factor on 11q
-
Treatment:
- Chemotherapy and surgery
- Radiation therapy may be added
- Stage I: 5 year survival 70% with chemo/ RT
Giant Cell Tumor of the bone
- Young adults (20-40 years), older adolescents (skeletally matured)
- F>M
- Epiphyseal location
- Knee, proximal humerus, radius
- Most are benign, locally aggressive
- May destroy cortex of bone and extend into soft tissue
What is the most common malignant bone tumor?
Metastatic Bone Tumors
- especially in adults
- 20X more frequent than primary bone tumors
Where do metastatic bone tumors go in the body?
- Mostly multiple
-
Solitary lesions may mimic a primary bone tumor and precede discovery of its source
- 70% go to axial skeleton (skull, ribs, vertebral column, sacrum)
- Mostly lytic
- May be blastic (bone-forming): breast, prostate
- 80%: breast, lung, thyroid, prostate and kidney (BLT-KP)
