Multiple Myeloma, Chondrosarcoma & Metastasis Flashcards
Chondrosarcomas are comprised of ____
Hyaline cartilage
The more aggressive a chondrosarcoma is, the (more/less) cartilage is produced
less
What are the 2 classifications of chondrosarcomas by location?
- central (intramedullary)
- juxtacortical (peripheral)
Most chondrosarcomas are (primary/secondary)
primary
Where do secondary chondrosarcomas originate?
form in pre-existing cartilage tumors:
- enchondromas: solitary 1%, Ollier 25%, Mafucci 50%
- osteochondromas: solitary <1%, HME 25%
Chondrosarcomas are very ____ growing
Slow
(low grade tumor)
Describe the histological appearance of a chondrosarcoma
- malignant chondrocytes
- necrosis
- hemorrhage
- stippled calcifications
- cystic change
What is the preferential location of chondrosarcoma?
- pelvis
- long bones (femur & humerus)
- ribs
What common location of chondrosarcomas may have a mass effect on nearby structures?
pelvis
What age group is primarily affected by chondrosarcomas?
40-60 years
(exception: clear & mesenchymal subtypes = teens-20s)
What is the etiology of chondrosarcoma?
multiple genes implicated
Where do chondrosarcomas typically metastasize to?
lungs, liver, kidneys, brain
(rare, very late stage)
Chondrosarcomas have a tendency to extend ____ bone
along (instead of beyond)
What causes the white appearance of chondrosarcomas on x-ray?
cartilage attracts Ca2+ –> calcification (NOT ossification)
(similar appearance to enchondroma)
How would a patient with a chondrosarcoma present clinically?
- insidious onset (up to 2 yrs)
- pain at affected site
- possible palpable soft tissue mass
What are the radiographic characteristics of a chondrosarcoma?
- localized bone destruction
- poorly-defined borders with cortex perforation
- radiopacities due to calcification or endochondral ossification
- soft tissue masses may be visible
(buzz word: “large calcified soft tissue mass”)
What pattern of destruction is seen in an chondrosarcoma?
motheaten lytic
What type of matrix calcification is seen in a chondrosarcoma?
stippled
Why are drug and radiation therapy less effective in treating chondrosarcomas than other malignant bone tumors?
low grade tumor –> less blood supply
What is another name for multiple myeloma?
Plasma cell myeloma
What is the most common primary malignant bone tumor?
Multiple myeloma
What age group is primarily affected by multiple myeloma?
50-70 years
What is the etiology of multiple myeloma?
Unknown
Multiple myeloma is a tumor of uncontrolled proliferation of ____ which produces ____
B-lymphocyte marrow
B-lymphocytes
(single cell lineage of B-lymphocytes)
What do B-lymphocytes produce?
Antibodies/immunoglobulins (Ig’s)
What is unique about immunoglobulins produced by multiple myeloma?
selectively make short chain only (no long chain)
What are Bence-Jones proteins?
Short chain of immunoglobulin proteins selectively produced by B-lymphocytes of multiple myeloma
What are the 2 major proteins in blood?
albumin
globulin
What is a normal A:G ratio?
albumin > globulin in blood
What happens to the A:G ratio with multiple myeloma and why?
- globulin > albumin
- reverses due to overproduction of Ig’s
What would you include in your differential diagnosis if you see aggressive activity on a radiograph of an older patient?
- metastasis (usually older)
- multiple myeloma (usually older)
- lymphoma (any age)
Multiple myeloma cells secrete ____ that recruit ____
cytokines
osteoclasts
What would alkaline phosphatase levels be in a patient with multiple myeloma and why?
normal
tumor releases hormone that is osteoblast-inhibiting –> less osteoblastic activity, no alk phos. released
What is the appearance of lesions in multiple myeloma?
- multiple 1-5mm lesions (lytic)
- histologically consist of sheets of plasma cells w/ varying degrees of differentiation
- large nuclei > cytoplasm
What is the preferential location of multiple myeloma?
- vertebrae
- skull
- ribs
- pelvis
- femur
How would a patient with multiple myeloma present clinically?
- lack of cardinal signs
- weight loss, cachexia (wasting)
- variable bone pain presentation (intermittent –> continuous; rapid onset following trauma; worse during day/activity/wt bearing)
- hypercalcemia
- anemia (manifests as fatigue)
- amyloidosis (10%)
- Bence-Jones proteins
Why would a patient with multiple myeloma present with fatigue?
- loss of white & red marrow (replaced by B-lymphocyte lineage) causes anemia
What would you suspect in a patient who says they chew ice a lot, have been progressively fatigued lately, and has pale mucous membranes inside their cheeks and under their tongue?
iron deficiency anemia
(need labs to diagnose; pale mucous membranes instead of pink)
What causes renal failure in a patient with multiple myeloma?
- overproduction of immunoglobulins which are destructive to kidneys
- results in altered GFR, creatinine, and presence of protein in urine
What is the prognosis of multiple myeloma?
- treatment options poor (radiation, chemo, marrow transplant)
- 90% die within 3 yrs (++ aggressive)
- infection or renal failure common causes of death (less normal marrow to produce functioning WBCs)
Metastatic bone tumors are also called ____
secondary bone tumors
What is the most common malignant tumor of bone?
metastatic disease
What is metastatic bone disease?
neoplasias (usually carcinomas) that metastasize to bone from any tissue in the body
What are the most common primary origins of metastasis to bone?
- breast
- prostate
- kidney
- lung
What is the most common pathway of metastatic spread to bone and why?
hematogenous
- vascular neogenesis (angiogenesis)
- tumor cells not sticky, shed easily into blood
Metastatic bone tumors are considered a ____-replacing disease
marrow (mostly red marrow)
What cancer has the highest mortality rate?
lung & bronchus
What are the common sites of metastasis in the skeletal system?
- lower thoracic spine to lumbar spine & pelvis due to gravity & Batson’s venous plexus
- proximal femur > proximal humerus
How does hematogenous metastatic spread commonly occur to the skeleton?
Batson’s vertebral plexus –> red marrow spaces (more vascular than yellow marrow)
What is Batson’s vertebral plexus also referred to as?
Basivertebral vv
What bones is red marrow found in?
- skull
- spine
- pelvis
- proximal humerus
- proximal femur
Primary breast cancer often metastasizes via what route?
lymphatic
A pancoast tumor that metastasizes to the upper ribs and thoracic spine spreads via what route?
direct extension
What are the 2 most common clinical manifestations of metastasis to bone?
- unexplained weight loss
- anemia manifesting as fatigue
What symptom is likely to develop due to the high glucose demand and angiogenesis of a metastatic tumor?
unexplained weight loss
What are the clinical manifestations of metastasis?
- unexplained weight loss
- anemia (fatigue)
- pain
- fever (night sweats) with late stage
- abnormal labs
What are the possible radiographic characteristics of metastasis to bone?
- osteoblastic, osteolytic, or mixed activity
- no soft tissue mass (rare)
What bone pathologies would you include in your differential diagnosis specific to a 50-year-old patient?
- fibrous xanthoma (20+)
- Paget disease (>50)
- secondary osteosarcoma (predisposing + >50)
- chondrosarcoma (40-60)
- multiple myeloma (50-70)
What bone pathologies would you include in your differential diagnosis specific to a 7-year-old patient?
- fibrous cortical defect (<8)
- polyostotic fibrous dysplasia (<10)
- simple bone cyst (<20)
- aneurysmal bone cyst (<20)
- primary osteosarcoma (<20)
- enchondroma (<20)
- ewing sarcoma (<20)
- osteochondroma (<20)
- chondroblastoma (5-25)
- osteoid osteoma (5-35)
What bone pathologies would you include in your differential diagnosis specific to a 22-year-old patient?
- fibrous xanthoma (20+)
- chondroblastoma (5-25)
- osteoid osteoma (5-35)
- giant cell tumor (20-40)
