Sarcomas Flashcards
What are sarcomas?
Connective tissue/mesenchymal tumors
Spread by blood
Different behaviors depending on tissue of origin and grade
Primary Bone Tumors
Kind
80% Osteosarcoma
Fibrosarcoma
Chondrosarcoma
Hemangiosarcoma
Primary Bone Tumors
Signalment
Mid to older aged dogs; also peak at 18-24 months
Large/giant breeds (rare in toy breeds)
Males > Females
Neutered > Intact (Rotties)
Primary Bone Tumors
Presenting Complaint
Lameness
+/- swelling
Canine Osteosarcoma
Bones inolved
Long Bones (Appendicular)
75% metaphyseal
Front legs > back legs
Away from the elbow and towards the knee (sometimes distal tibia)
Flat Bone (Axial) Bones of the head, ribs, pelvis, vertebrae
Canine Osteosarcoma
Diagnosis
Radiographs (must differentiate from fungal or bacterial osteomyelitis)
Cytology (Alk Phos staining; takes up stain suggesting osteosarcoma)
Histopathology (definitive diagnosis)
Canine Osteosarcoma
Staging
Look at lungs! -> high potential for metastasis to lung (essential to look here)
Metastasis most likely to grow after primary tumor removed!
CT is far more sensitive and recommended if considering amputation (can pick up on smaller sized mets)
1 lung lesion is alright but when there are multiple be careful
Canine Osteosarcoma
If see mets in lung what should you consider?
Possibly not amputating the leg
If leg is amputated then do something to decrease lung tumor size (chemotherapy)
Canine Osteosarcoma
Poor prognosis with
Lung or bone metastasis (especially if large masses)
Lymph node metastasis
Elevated Alk Phos
Monocytosis
Young age
Canine Osteosarcoma
Treatment and Prognosis
No therapy
Painful!
Should at least give NSAIDs and pain meds
Canine Osteosarcoma
Treatment and Prognosis
Amputation/No Chemo
3-4 months
Canine Osteosarcoma
Treatment and Prognosis
Radiation for pain control
4-6 months
Canine Osteosarcoma
Treatment and Prognosis
Pain Meds (NSAIDs, Opioids)
4-6 months
Canine Osteosarcoma
Treatment and Prognosis
Bisphosponates
4-6 months
Canine Osteosarcoma
Vaccine?
New therapy
Target: Her-2/Neu Listeria
Canine Osteosarcoma
Aggressive therapy for appendicular tumors
Amputation and chemotherapy (9-12 months)
Cisplatin (high toxicity)>Carboplatin>Doxorubicin
Carboplatin alternating with Doxorubicin
NSAIDs
Note: can start chemo prior to amputation; just closely monitor wound healing post-sx
Canine Osteosarcoma
Axial tumors
Treatment
Difficult due to inability to remove surgically (vertebrae, pelvis)
Palliative radiation (cannot damage CNS) Pain medication
Local recurrence is common
Surgical removal of mandible/ribs + chemotherapy
Feline Osteosarcoma
Background
Rare but it happens
Metastasis seems to come much slower than in dog (takes years)
Amputation = treatment of choice
Soft Tissue Sarcomas
What are they?
Tumors arising from supportive tissues, variety of types, all behave very similarly
Soft Tissue Sarcomas
Examples
Fibrosarcoma Hemangiopericytoma Nerve sheath tumor Leiomyosarcoma Synovial cell sarcoma Liposarcoma Malignant fibrous histiocytoma
Soft Tissue Sarcoma
What is important to know?
Tumor grade!
Soft Tissue Sarcomas
Signalment
Larger, older dogs
Any breed or any age really
Soft Tissue Sarcomas
Presentation
Usually a mass (SQ)
Tumor can arise from internal soft tissue
Soft Tissue Sarcomas
Biologic Behavior
Locally aggressive, invasive, poorly defined margins
Slow to metastasize:
Spread to lungs more than lymph nodes
Grade should be predictive
Mitotic index (most important prognostic indicator): > 20 is grade III (poor prognosis and need large margins)
Soft Tissue Sarcomas
Diagnosis
Cytology suggestive
Incisional biopsy; required for true diagnosis and grade
Excisional biopsy; be sure you know margins