MSK Oncology Flashcards
What lineage are MSK tumors from?
Mesenchymal cells
Sarcoma
Malignant tumor of mesenchymal cell origin
Where is most common site for soft tissue sarcomas?
Anterior quadriceps
2 most common soft tissue sarcomas.
2 others
Liposarcomas and undifferentiated fibrosarcomas are most common.
2 others include rhabdomyosarcoma and synovial sarcoma
How are soft tissue sarcomas treated?
Surgery and radiation
Rhabdomyosarcoma Type Age Origin Treatment
Most common soft-tissue sarcoma in kids.
Origin is skeletal muscle.
Treat w/ excision, radiation, and surgery.
Synovial sarcoma Type Age Location Morphology Treatment
Soft tissue sarcoma Commonly seen in young adults Occurs in joints of hands / feet. Cells appear to form synovial clefts. Treat w/ surgery and radiation.
Where do most sarcomas metastasize?
Lungs
Are soft tissue or bony sarcomas more common?
Soft tissue
2 types of benign bone tumors
Unicameral bone cysts
Fibrous dysplasia
Unicameral bone cysts Type Morphology Age Location Prognosis Treatment (4)
- Benign bone tumor
- Well circumscribed lytic lesion in bone
- Often seen in humerus of kids. Developmental, starting close to growth plate. Smooth outline.
- Most spontaneously resolve w/ skeletal maturity. May require surgery if it persists.
- Treatment options: bone graft, injection, cryotherapy, and observation
Fibrous dysplasia Type Pathology Age Pathognomonic feature Prognosis Albright's Syndrome Imaging Histology Treatment
- Bone hamartoma (benign neoplasm)
- Causes lytic bone deformity w/ fractures.
- Most common in kids.
- Pathognomonic features is that bone is being laid down by fibrous stroma rather than by rimming osteoblasts.
- Quality of bone often improves w/ age.
- Albright’s Syndrome – severe form in which pxs have precocious puberty, café au lait spots, and fibrous dysplasia.
- X ray shows lytic lesions w/ ground glass
- Histology – fibrous tissue b/w bone trabecular
- Medical tx is best. Surgery is reserved for chronic pain or increasing deformity.
4 types of malignant bone tumors
Osteogenic sarcoma, Ewing sarcoma, MM, metastasis
Osteogenic sarcoma Type Age Cell activity Imaging Treatment
- Highly aggressive malignant bone tumor
- Often seen in kids.
- Cells make osteoid (aids in diagnosis).
- Imaging – Osteoblastic bone is formed in canal and a “SUNBURST” periosteal reaction surrounds the bone.
- Treatment is based on limb salvage surgical resection w/ preop and post chemotherapy.
- 90% of pxs can have legs salvaged. Resect bone and then transplant donated femur.
- In very young pxs that have lots of growth left, amputation is tx of choice.
Ewing Sarcoma Type Cell of origin Age Histology Treatment
- Malignant bone tumor
- Primitive tumors w/ cells that are difficult to determine origin. Usually osteolytic.
- Seen in kids and young adults
- Histology shows sheets of small round blue cells that stain positive for glycogen.
- Treatment involves chemo, surgery, or radiation. Depends on site. Surgery done in expendable bones. Radiation done in bones that have lots of remaining growth.
Multiple Myeloma Type Isolated form Urine findings Imaging Treatment
- Malignant plasma cell tumor in marrow. Almost always lytic.
- Called isolated plasmacytoma if only found in one bone. 80% progress to MM in 5 years.
- Urine proteins may be high
- Bone scan is usually cold since there is very little osteoblastic activity.
- Treat w/ chemo, immobilization, bisphosphonates (block osteoclasts to reduce risk of fracture). NOT surgery b/c it is a systemic disease.
Metastatic bone disease Type of cancer Most common sites Blastic vs lytic types Diagnosis Treatment
- Often from carcinomas.
- Most common sites are vertebrae, pelvis, femurs, and humerus
- Prostate cancer is often blastic.
- Lung cancer and renal cell carcinomas are often lytic.
- Breast cancer may be blastic or lytic.
- All pxs w/ metastatic disease should get a bone scan. May be cold if tumor is not blastic.
- Treatment – radiation + chemo of primary tumor. Surgery reserved for pxs who do not respond. Prophylactic skeletal fixation done in pxs w/ fracture or who are about to fracture. Radiation decreases bone strength.
Malignant cancers by age
Osteogenic sarcoma and Ewing sarcoma are more common in kids.
Lymphomas are common in 2nd / 3rd decade.
MM is most common malignant bone tumor in pxs > 40 y/o
Achondroplasia mutation / effects
Dominant mutation in FGFR3 –> disruption of cartilage development and growth of long bones
Osteogenesis imperfects mutation
Presentation
Dominant mutation in type 1 collagen
Usually presents in infancy. Bowing / deformities / fractures of bones. Blue-gray sclerae.
