Tumor Flashcards
What is the characteristic physical exam finding with desmoid tumors (extra-abdominal fibromatosis)?
Hard as rock
How might an epithelioid sarcoma present?
Small superficial nodule that may ulcerate
What is the reactive zone of a tumor?
An interface between the tumor and normal tissues. It contains edema fluid, inflammatory cells, fibrous tissue and tumor-cell satellites
When ordering an MRI to further evaluate a soft tissue lesion, should you order T1 or T2?
Both
Where do sarcomas most commonly metastasize?
Lung
What are the 2 prerequisites for limb-salvage procedure?
- Local control of the lesion will be at least equal to that achievable without salvage. 2. The salvaged limb will be functional
How often should MRI be performed after treatment of soft tissue tumor?
Baseline MRI 3 mo after sx then at 1 yr intervals for 5 years
How often should chest radiographs and chest CTs be performed after soft tissue tumor treatment?
At 3 mo intervals for 2 yrs then at 6 mo for 6 yrs. At 8 yrs get them once/yr
What are the 5 most common tumors that mets to bone?
PB KTL (Lead Kettle). Prostate, Breast, Kidney, Thyroid, Lung. Most are lytic lesions, some breast are blastic.
Where is the epicenter of most mets lesions?
Intramedullary canal. Rare to be intra or juxtacortical.
After a skeletal lesion has been identified, what should be done next?
Bone scan to determine whether lesion is isolated or multiple bones are involved.
What is difference between a stress-riser cortical perforations and open -section defect?
Stress riser is a cortical defect that is small than the cross sectional diameter of the bone. It dec torsional rigidity by 60%. Open section is larger than cross-sectional diameter and dec torsional rigidity by almost 90%
Effect of osteoblastic vs lytic lesion on strength and stiffness of bone?
Blastic dec stiffness of bone. Lytic lesion dec BOTH strength and stiffness.
What is the characteristic radiographic appearance of a non-ossifying fibroma (metaphyseal non ossifying fibroma)?
A lucent lesion that is metaphyseal , eccentric “bubbly” and surrounded by a sclerotic rim.
What is the most common benign bone tumor in childhood?
Non ossifying fibroma
What is the demographic, location and treatment for Non-ossifying fibroma?
Age 5-15, 80% in LE, most lesions resolve on own and observation is treatment. May need casting if risk of pathologic fracture. Lare symptomatic lesion may require curettage and bone graft
How might you distinguish a NOF from ABC or UBC?
NOF has hemosiderin on Histology
What benign lesion that is extremely rare may appear very similar to a NOF?
Benign fibrous histiocytoma
This lesion is seen in an 18 yo. Painful lesion. What is it and how treated?
Desmoplatic fibroma. Malignant low-grade tumor. Found in metaphysis ages 15-25. Wide surgical resection. Must remove joint in young patients
What is the most common soft tissue sarcma in ages 55-80?
MFH (malignant fibrous histiocytoma). This and fibrosarcoma are treated as same entity
Where do most chordomas present?
50% occur in sacrum and coccyx
What is a classic histologic appearance of a chordoma?
Foamy, vacuolated, physaliferous cells
How might someone with a chordoma present?
Insidious onset of back pain. May copmplain of pelvic pain or GI symptoms like constipation or loss of rectal tone.
Where do hemangiomas occur mostly?
Vertebral body…some in cranio-facial bones
What does this xray depict?
These are the characteristic vertical striations or “honey comb” appearance or “jail bar” appearance of a hemangioma in the vertebral bodies
What are the three scenarios in which lymphoma presents in bone?
3 ways: 1. as solitary focus 2. as metastatic disease 3. mix bone and soft tissue
When is surgery used to treat lymphoma?
To stabilize fractures or prophylactically treat them. Treatment for bony lymphoma is multi agent chemo +/-radiation
What two tumor markers go along with lymphoma?
CD 20 and CD 45
What is the radiographic description of lymphoma?
large ill-defined diffuse lytic lesions with a subtle mottled appearance
Why must chordomas have a long follow up period?
Because they metastasize late
What is the classic histologic appearance of multiple myeloma?
Sheets of plasma cells. When well differentiated the plasma cells have an eccentric nuclues and chromatic “clock faced” appearance.
What is this?
The classic multiple myeloma histology. Eccentric nucleus with clock face appearance.
What are the 3 plasma cell dyscrasias an orthopedist should know about? (myelomas)
Multiple myeloma, Solitary plasmacytoma, Osteosclerotic myeloma
Radiographic appearance of multiple myeloma?
Punched out lytic lesions with ballooned appearance.
What is the diagnostic criteria for a solitary plasmacytoma?
- Solitary bone lesion
- Histologic confirmation of a plasmacytoma
- Bone marrow biopsy of <10% plasma cells
Important to distinguish from multiple myeolma bc has much better prognois. >50% progress to multiple myeloma.
Bence jones protein are associated with what?
Multiple myeloma.
Pts may also have renal failure (inc Cr) and hypercalcemia
M spike on electrophoresis?
Multiple myeloma. Mostly usually IgG, can be IgA or least commonly IgM
What is osteosclerotic myeloma?
Rare variant of myeloma characterized by bone lesions that are associated with a chronic inflammatory demyelinating polyneuropathy
How might someone with Osteosclerotic myeloma present?
Usually with sensory symptoms of tingling, pins and needles etc followed by motor weakness. Sensory an motor changes begin distally then progress proximal and are symmetric
What is the acronym POEMS?
Related to osteosclerotic myeloma describing thier constellation of symptoms.
Polyneuropathy, Organomegaly, Endoncrinopathy, M-protein, Skin changes
When there is concern for multiple myeloma, why is a skeletal survery so important?
Because bone scan may be “cold” in 30% of people
What bone tumor is more common in women than in men?
Giant cell tumor
What is the appearance and location of giant cell tumor?
Usually metaphysis extending to epiphysis and near subchondral bone. Purely lytic destructive lesion.
What is the rare, but characteristic appearance of ewings sarcoma?
Onion skinn appearance from periosteum being lifted off in layers
What chromosomal translocation is always present in Ewings?
11:22
Histology of Ewings?
Small round blue cells
What age group do we see Ewings?
5-25
What workup is always part of Ewings workup that is not usually part of staging for osteosarcoma?
Bone marrow biopsy to rule out bone MARROW mets
In what age group do we see ABC?
75% are <20
Characteristics of ABC?
Reactive bone lesion with blood filled cavities. Expansile, eccentric and lytic lesion with bony septae (“bubbly appearance”). Classically have thin periosteal rim of new bone. MRI shows Fluid/fluid levels
How does UBC usually present?
Usually with pain after a minimal trauma. From fracture caused by minor trauma.
What age group for UBC and m/c location?
Age <20. Location is prox humerus
What is the fallen leaf sign
“fallen leaf” sign is a pathologic fracture with fallen cortical fragment in base of empty cyst is pathognomonic for UBC
Treatment for ABC vs UBC
In general ABC requires curettage, and UBC is steroid injection.
Which is more expansile, ABC or UBC?
ABC may be wider than physis. UBC is generally no wider than the physis
What bone lesion has a histology described as alphabet soup and chinese letters?
Fibrous dysplasia
Pts with fibrous dysplasia may have what type of skin involvement?
Yellow or brown spots like cafe au lait spots
When bone lesions and endocrine abnormalities, especially precocious puberty, are found together with skin abnormalitites, this is called what?
Mcune Albright syndrome. The bone lesions are likely fibrous dysplasia.
Gene mutation with fibrous dysplasia?
GSalpha
Most common location for UBC
Prox humerus
