Bone Tumors (Week 3--Nelson) Flashcards
Bone tumors
Rare
They are mesenchymal tumors and mesenchymal tumors don’t follow the normal dysplasia –> carcinoma in situ –> carcinoma pattern
Must have clinical and radiological correlation
Primary bone tumor
Primary bone tumor (start in the bone) that is malignant is called a sarcoma
This is NOT cancer that has metastasized (ie breast cancer metastatic to bone is NOT bone cancer!)
Also, this is NOT bone marrow/hematopoietic cancer
Malignant bone tumors
De novo malignant tumor (don’t know what caused it)
From benign to malignant
Secondary from radiation
Malignant primary bone tumors
Very rare (<.01% of malignancies)
Aggressive
Hematogenous spread of sarcomas (conversely, remember carcinomas go through lymphatics)
Correct diagnosis depends on clinical history, radiographic studies, histology
Osteosarcoma
“The mother of all bone tumors”
Most common primary malignant bone tumor
Two peaks: 10-20 (KIDS) and 60-70
Pain and swelling
Different types and grades of osteosarcoma
Pathogenesis not understood in most cases
Known to follow radiation, Paget’s disease
Most common in long bones, metaphysis (KNEE) (but can also be in other places like craniofacial, small bones, extraskeletal (soft tissue))
Aggressive, fatal disease
Osteosarcoma on radiology
Malignant appearance
Infiltrative, destructive
Blastic, mineralized
Codman’s triangle, sunburst pattern (STEP 1)
Osteosarcoma gross pathology
Filling medullary portion, breaking through cortex, extending into soft tissue
Osteosarcoma histology
Plump neoplastic osteblasts
Delicate, immature osteoid production (these tumors make bone)
Infiltration and destruction of normal bone
Variants of osteosarcoma
Not important what they are!
Osteoblastic
Chondroblastic
Telangiectatic
Small cell
Low grade intramedullary
Periosteal
Parosteal
Fibroblastic
Dedifferentiated
Giant cell rich
Chondroblastoma-like
Osteoblastoma-like
Intracortical low-grade
Etc…
When does it not matter what specific variant the osteosarcoma is?
When the osteosarcoma is high grade, it doesn’t matter what the specific variant is
Most ARE high grade!
Where can osteosarcoma spread to?
Lungs, just like many other sarcomas
Osteosarcoma treatment and prognosis
Treatment: chemotherapy (at least 3 types, high grade), excision, rarely do amputations anymore
Prognosis: 60-75% 5 year survival (much improved)
Chondrosarcoma
Second most common primary bone tumor (after osteosarcoma)
Chondro = cartilage
Adults age 40-60
Pelvis, flat bones, only sometimes in long bones
Usually de novo
Can be from osteochondroma
Most are grade I (low grade), but can be grade II or III
Low grade may “dedifferentiate” into high grade sarcoma
Chondrosarcoma on radiology
Lobulated
Destructive mass with calcification
Chondrosarcoma gross pathology
Lobulated
Destructive
White/translucent
Calcified
Chondrosarcoma histology
Lobules of cartilage
Permeating bone (invasive)
Calcification
Chondrosarcoma treatment
Excision
Generally NOT chemotherapy sensitive
Ewing Sarcoma/PNET
A member of the Primitive Neuroectodermal Tumor (PNET) family
11:22 translocation
Usually in children
Diaphyseal (long tubular part of the bone)
Present as pain, mass
May be very rapidly growing
Ewing sarcoma/PNET on radiology
Lucent lesion with reactive bone formation, edema
Looks much like osteomyelitis, LCG
Spiculated?
Ewing sarcoma/PNET histology
Malignant small blue round cells
High mitotic rate
Geographic necrosis
Special tests help: cytogenetics, IHC
Ewing sarcoma/PNET treatment and prognosis
Chemotherapy
Radiation therapy
Surgical excision
Prognosis: improving, to 60%
Chordoma
Adult tumor
Usually in sacrum, spine
Presents as a mass with bone destruction
Thought to be from notochord remnants
Malignant
Chordoma on radiology
Expansile lesion
Destroying bone and extending into soft tissue
Chordoma gross pathology
Lobulated
Myxoid
Chordoma histology
Cords of cells in loose myxoid matrix
Bubbly “physaliphorous” cells
Chordoma treatment and prognosis
Treatment: excision
Prognosis: high recurrance rate, intermediate metastatic potential
Transformation
Benign primary bone tumors transform to malignant forms
Fibrous dysplasia
Benign expansile bone tumor
Long bones, facial bones
Can transform to osetosarcoma (bad!)
Osteochondroma transformation to secondary chondrosarcoma
Osteochondroma is benign
But 10% chance of malignant change to chondrosarcoma
Giant cell tumor
Benign
Epiphyseal tumor of adults (skeletally mature)
Need to rule out hyperparathyroidism, which causes identical “brown tumor”
Giant cell tumor on radiology
Lucent, destructive mass in epiphysis
Giant cell tumor treatment and prognosis
Treatment: curettage, excision
Prognosis: 20% recurrance rate, but only rarely malignant transformation
Malignant giant cell tumor
Rare transformation to malignancy
Turns to high grade sarcoma
Most common following radiation therapy for benign giant cell tumor
May occur de novo
Plasmacytoma
Tumor of malignant plasma cells
If there are multiple, then multiple myeloma
Monoclonal immunoglobulin spike in SEP
Atypical plasma cells
Plasmacytoma on radiology
Punched out lesions
Lytic
Cancers that metastasize to bone
Breast
Renal
Thyroid
Prostate
Most common “bone” tumor
Treatment is curettage, fixation (hardware)
Often present with pain or pathologic fracture
Clinical information important in diagnosing bone tumors
Age
Presentation (time period)
Radiographic
Location (epiphysis, metaphysis, diaphysis, etc)
Where do we look for metastasis of bone cancer?
Metastasize from leg bones to lungs, so look in lungs
Why would osteosarcoma be mistaken for a reactive process?
Because both processes are laying down immature bone
