Oncology Flashcards
Location of primary tumors that metastasize to bone
Breast Lung Renal Thryoid Prostate
***spine is most common area of metastasis
Osteolytic bone lesions occur via activation of ______ by ______
osteoclasts; RANK-L
***Denosumab inhibits RANK-L and is especially effective in giant cell tumors as they secrete RANK-L
Osteoblastic bone metastases secrete ______
endothelin-1
Almost always biopsy prior to surgery, and if you are not planning the tumor surgery then don’t do the biopsy.
Do not assume bony lesions are metastases from a known cancer, always do a biopsy.
Key points to remember when doing a biopsy?
- You must go THROUGH a compartment, not between
- Biopsy through the compartment you will be doing definitive surgery, this should be an extensile approach
- Do not go through a joint
Mirel criteria for prophylactic fixation
Consider fixation for score >7
Generally this is in patients with LE/pertrochanteric, lytic lesions, >2/3 width of bone and moderate or functional pain
Ewing Sarcoma tumor marker
t(11:22)
Gene: Fusion protein (EWS-FLi1)
Rhabdomyosarcoma tumor marker
t(2;13)
Gene: Pax3-FKHR
Myxoid Liposarcoma tumor marker
t(12:16)
Gene: TLS-CHOP
Synovial Sarcoma tumor marker
t(X:18)
Gene: SYT-SSX1, 2, or 4 fusion protein
Chondromsarcoma tumor marker
t(9:22)
Fusion protein EWS-CHN
Osteosarcoma tumor genes
mutations in p53 and Rb tumor suppressor genes
Giant cell tumor mutation?
Telomere translocation
How would you manage a metastatic renal cell carcinoma to the intertroch region?
- Preoperative embolization (very vascular tumors with high risk of significant blood loss)
- Wide resection and arthroplasty
- **Prophylactic fixation is no longer enough as patients are living longer on chemo agents and resection needs to be done to prevent recurrence and further mets
Synovial sarcoma
- Is NOT located in the synovium. Commonly located in the lower extremity (plantar aspect of foot)
- Image lungs and local regiona lymph nodes to r/o metastasis
- Size correlates with 10-year survival, <5cm 88% survival
- t(X;18), SYT-SSX fusion protein
- Stains positive for Vimentin, epithelial membrane antigen, S-100
- Histology: sheets of spindle cells and epithelial “gland-like” formations
Types of soft tissue sarcomas and general treatment
- Synovial sarcoma (plantar aspect of foot)
- Liposarcoma (intermuscular)
- Rhabdomyosarcoma
- Fibrosarcoma
Radiation therapy and wide surgical resection
Liposarcoma
- Between muscles (intermuscular)
- MRI: heterogeneous soft tissue mass
- Histology: lipoblast (signet ring cell)
- Translocation: 12;16
- Metastasize to lung and retroperitoneum
Myxoma
Intramuscular.
Easily confused with lipoma or soft tissue sarcoma, so must know histology.
-Histology: BLAND, hypocellular myxoid stroma, NO signet ring cells to suggest lipoblasts.
What are the 3 small round blue cell tumors?
How can these be differentiated?
- Multiple myeloma
- Lymphoma
- Ewings
Can be differentiated by age: <5 yo = Neuroblastoma or leukemia 5-10 yo = Eosinophilic granuloma 5-30 yo = Ewing sarcoma >30 yo = Lymphoma >50 yo = Myeloma
Multiple myeloma
- ADULT >40 yo
- Twice as common in African Americans
- Can present with end organ damage (hypercalcemia, renal failure, anemia)
- Work-up CBC, SPEP (M spike), UPEP (Bence Jones proteins)
- XR multiple punched out lytic lesions
- Histology: small round blue cell tumor
- Treatment: multi-agent chemo + radiation. Prophylactic fixation as indicated.
Lymphoma
- Adults
- Usually non-Hodgkins B-cell Lymphoma
- Found in pelvis, spine and ribs (bones with persistent red marrow)
- B-cell symptoms: fever, night sweats, weight loss
- Labs can show neutropenia and high lymphocyte count
- Large, diaphyseal, moth-eaten, lytic lesions (very hot on bone scan)
- Histology: small round blue cell tumor. CD 20+, CD 45+. Lymphocyte common antigen +
- Treatment: multi-agent chemo. Radiation if refractory to chemo.
Ewing’s Sarcoma
- KIDS
- Mimics infection with pain, fever, elevated ESR and WBC
- Agressive, lytic lesion of diaphyseal long bone. The lytic area of bone can also have sclerosis or be reactive.
- MRI often reveals large soft tissue component
- Work-up should also include bone marrow biopsy to rule out metastasis to marrow
- t(11;22)
- p53 mutation and EWS-FLI1 fusion protein
- Treatment: chemo + limb salvage resection + radiation (if poor response to chemo or positive margins)
Osteosarcoma tends to metastasize to the
pulmonary system
Osteosarcoma mutations
Rb and p53
Osteosarcoma treatment
Neoadjuvant chemotherapy + wide resection + adjuvant chemotherapy
Enchondroma XRay findings
popcorn calcification
Talengiectatic osteosarcoma Xray findings
Destructive, expansile lytic lesion with loss of cortex and no ossification.
MRI shows fluid-fluid levels
Aneurysmal bone cyst Xray findings
Expanding lytic lesions with a circumferential cortical rim, septated with bubbly appearance
Chondrosarcoma
- Adults
- Cartilage tumor
- Cartilage tumors are slow growing, thus DO NOT RESPOND TO CHEMO OR RADIATION
- XR can have popcorn calcification like enchondroma
- MRI can show soft tissue involvement
- Treatment is wide resection with reconstruction/prosthesis
Giant Cell Tumor
- Benign aggressive tumor in the metaphysis of long bones (proximal tibia, distal radius, distal femur)
- Despite being benign, it can rarely metastasize to the lungs so get CXR or CT chest
- XR: lytic lesion extending into subchondral bone
- Low risk of malignant transformation, but if it was to transform it would likely become fibrosarcoma
- Treat with curettage and bone grafting
PVNS MRI finding
Hypointense on both T1 and T2
Aneurysmal bone cyst
- Metaphyseal lesions
- XR: lesion expands the cortex
- MRI: fluid-fluid levels
- Histology: “lakes of blood”
- Treatment: curettage and bone grafting
- Radiation increases risk of malignant transformation
PVNS MRI finding
Hypointense on both T1 and T2
Aneurysmal bone cyst
- Metaphyseal lesions
- XR: lesion expands the cortex
- MRI: fluid-fluid levels
- Histology: “lakes of blood”
- Treatment: curettage and bone grafting
- Radiation increases risk of malignant transformation
This tumor’s pain is relieved by NSAIDs
Osteoid osteoma
*NSAIDs effective because tumor has high PGE2 and COX 1 and 2