Malignancy of Bone Flashcards
What is the most common malignancy of bone?
metastasis
What is the most common primary malignancy to metastasize to bone in a 1 year old?
neuroblastoma
(<2yrs)
What are the most common primary malignancies to metastasize to bone in a 5 year old?
- Ewing sarcoma
- osteosarcoma
- lymphoma
(>2yrs)
What is the most common primary malignancy to metastasize to bone in adult females?
breast
What is the most common primary malignancy to metastasize to bone in adult males?
prostate
What is the second most common primary malignancy to metastasize to bone in adults?
lung
What is the third most common primary malignancy to metastasize to bone in adults?
thyroid
What is often the cause of death in patients with non-skeletal primary malignancies?
metastasis to bone (marrow replacement, anemia)
What are the clinical findings of metastasis to bone?
- age 50-75
- night pain & deep boring bone pain
- patho Fx
- Hx of cancer
- unexplained weight loss
- anemia (fatigue, pale mucus membranes)
- fever (night sweats)
- soft tissue mass
- deformity
What are the lab findings for blastic metastasis to bone?
- ^ESR/CRP
- ^alkaline phosphatase
- normal serum Ca2+
What are the lab findings for lytic metastasis to bone?
- ^ESR/CRP
- ^serum Ca2+
What lab findings may be elevated specifically in prostate metastasis to bone?
- acid phosphatase
- prostate specific antigen (PSA)
What are the metastatic routes of spread?
- hematogenous
- lymphatic
- direct extension
What is the most common metastatic route of spread? Why?
hematogenous
- tumors create vascular supply (angiogenesis)
- O2 + glucose available
- malignant cells shed easily -> into bloodstream
Why are the lumbar spine, pelvis and proximal femur common areas of metastasis?
- ^^blood in area
- gravity
- Batson’s venous plexus (no valves)
What is the most common radiographic pattern of metastatic disease to bone?
osteolytic
What are the most common osteolytic primary sites of malignancy?
- lung
- breast
- prostate
- colon
- renal
- thyroid
- skin
What are the most common osteoblastic primary sites of malignancy?
5 B’s Lick Pollen:
- Bronchogenic
- Breast (#1 in females)
- Bowel
- Bladder
- Brain
- Lymphoma
- Prostate (#1 in males)
Are radiographic lesions with mixed pattern of destruction considered aggressive or non-aggressive?
aggressive
Why can’t radiographs rule out metastasis?
requires 30-50% bone destruction to visualize
What would a benign blastic lesion of bone look like on a bone scan?
not hot
What would a malignant blastic lesion of bone look like on a bone scan?
hot
What is a superscan?
bone scan that appears normal but shows no technetium taken up by the bladder/kidneys, indicating widespread metastasis with no extra technetium to be excreted
What type of follow-up imaging is best for bone marrow and soft tissues?
MRI with contrast
(contrast goes to areas of neovascularization)
Where should you refer your patient if you suspect metastasis to bone?
primary care physician
(NOT to oncology)
What are the most common target sites of metastasis to bone?
- lumbar spine
- pelvis
- proximal femur
- axial skeleton (including skull)
- proximal humerus
Metastasis beyond the elbow or knees is called ____
acral metastasis
(acral = distal)
What general pattern of destruction is more common in the calvarium?
lytic
(only 10% are blastic)
What part of the spine is commonly targeted by metastasis early on?
osteolytic pedicle destruction
What radiographic sign involves a missing pedicle and no stress hypertrophy?
winking owl sign
What radiographic sign involves bilateral missing pedicles?
blind vertebra
How does vertebral body destruction compare to bowel gas radiographically?
can still see cortical bone through bowel gas
What is the term for a single densely blastic vertebra on a radiograph?
ivory vertebra
What is the differential diagnoses mnemonic for an ivory vertebra?
IHOP:
- idiopathic (Dx of exclusion)
- hodgkin lymphoma (20-40yrs)
- osteoblastic mets (>50yrs)
- Paget Dz (>50yrs)
If you see an ivory vertebra on a radiograph, what is the first question you should ask yourself?
is there vertebral expansion or cortical thickening?
If you see an ivory vertebra on a radiograph, and no vertebral expansion or cortical thickening, what is the next question you should ask yourself?
is there anterior body scalloping?
If you see an ivory vertebra, and vertebral expansion or cortical thickening, what does this indicate?
Pagets disease
If you see an ivory vertebra on a radiograph, no vertebral expansion or cortical thickening, with anterior body scalloping, what does this indicate?
Hodgkin lymphoma
If you see an ivory vertebra on a radiograph, no vertebral expansion or cortical thickening, and no anterior body scalloping, what does this indicate?
osteoblastic mets
What follow-up imaging is needed if you see an osteoblastic pattern of destruction on a radiograph?
bone scan
What is a cookie bite lesion?
cortical destruction of bone appearing as a “bite” out of bone
What is the term for metastasis to bone that appears as a bubbly lytic lesion?
blow out metastasis
What is the mnemonic for the 4 malignancies that metastasize in a blow out fashion?
RATS
- renal cell carcinoma
- adrenal (pheochromocytoma)
- thyroid carcinoma
- skin (melanoma)
What is the typical pattern of destruction of blow out metastasis?
permeative/motheaten, but can be geographic lytic
What is a Pancoast tumor?
apical lung tumor (squamous cell carcinoma)
What is of concern with a Pancoast tumor?
direct extension to sympathetic chain, causing Horner’s syndrome
What are the signs of Horner’s syndrome?
- anhydrosis (dry eye)
- myosis (unreactive pupil)
- ptosis (droopy eyelid)
What are the common primary sites of acral metastasis?
- lung
- breast
- kidney
