16 - Musculoskeletal Neoplasia Flashcards
Primary bony neoplasia
Neoplasia arising directly from the bone
Secondary bony neoplasia
Spread from an adjacent site
Monostrotic
Lesion affecting a single bone
Polystotic
Lesion affecting more than one bone
Diagnostics of skeletal neoplasia
CBC, serum, urinalysis
Cytology for neoplasia requires
Heavy sedation
Best to sample cytology where
Closer to center of lesion
Accuracy of cytology
70%
Tools needed for biopsy
Jamshidi and Michele trephine
Risk of biopsy
Pathological fracture, non diagnostic sample
Accuracy of biopsy
80 - 90%
Thoracic CT for lesion
1 mm
Thoracic radiographs for lesion s
7 - 9 mm in size
Most common primary bone neoplasma
Osteosarcoma
Osteosarcoma primarily affects
Appendicular skeletal
Two types of osteosarcoma
Endosteal, periosteal, parosteal
Endostteal
Most common form arises from medullary cavity
Periosteal
Can invade into medically cavity from periphery and cause bony lysis and reactive bone formation
Parosteal
Arises from periosteum, forms an expansive mass that surrounds but does not invade cortical bone
Least aggresive osteosarcoma
Parosteal
Common locations of osteosarcoma
Distal radius, distal femur, proximal tibia, proximal humerus
Radiograph of osteosarcoma
Cortical lysis, periosteal reaction, extension of osteogenesis into adjacent soft tissues, loss of trabecular pattern in metaphyseal bone
Gross metastasis at time of initial presentation :
15%
Where does osteosarcoma like to metastasis
Lungs , bones, lymph nodes
Prognostic indicators of osteosarcoma
Age, body weight, metastasis?, elevated ALP
Elevated ALP indicated of
Tumor burden if elevated within 40 day sof treatment
Surgery of osteosarcoma
Amputation, fracture repair of pathological fracture, partial amputation
Radiation therapy treatment for osteosarcoma
Stereotactic radio surgery, palpitations RT
Stereotactic radio surgery
Single, large targeted dose of radiation
Palliative RT
Reduces pain/inflammation to improve quality of life for dogs that cannot undergo amputation
Chemotherapy often in conduct with
Amputation to increase survival time
Chemotherapy drugs
Doxorubicin, Cisplatin
Conservative managements
Analgesia and biphosphonates
Ideal treatment
Amputation and chemo
Bisphosphoates
Helps decrease bones resoprion
Amputation ST
6 m
Amputation w chemo ST
12 - 14 m
RT alone ST
4 - 10 m
Conservative management ST
2 - 3 m
Osteosarcoma in cats of what age
8 - 10 year
Treatment for cats with osteosarcoma
Amputation
Second most commone appendicular neoplasma
Chondrosarcoma
Chondrosarcoma lower
Metastatic rate
Chondrosarcoma often found in what skeleton
Axial skeleton
How do you treat chondosarcoma
Amputation treatment of choice
Prognostic factors condorosarcoma
Better if skull or appendicular
MST of Chondrosarcoma amputation
32 months
Secondary bone neoplasia sites commonly affected
Humerus, femur and vertebrae
Secondary bone neoplasia
Mammary, prostatic, pulmonary, hepatic, hemangiosarcoma, osteosarcoma
Joint neoplasia common sites
Elbow and stifle
Synovial cell sarcoma common sites
Elbow and stifle
Synovial histocytic sarcoma common sites
Stifle - secondary to chronic inflammation
Look alike neoplasia
Fungal ( blasto), Osteomyelitits, Bone cysts , RUIN
Osteomyelitis characterized by
More evident region of demarcation between normal and abnormal bone
Bone crust seen in
Younger dogs, uncommon, DX with bone biopsy
RUIN
Radioulnar ischemic necrosis
RUIN is
Permeating destruction of bone which extends to the interosseous ligament region to the radius and ulna