Soft Tissue Sarcoma & Osteosarcoma in Canines

Soft Tissue Sarcoma / Osteosarcoma David Hunley, DVM, DACVIM (Oncology) Soft tissue sarcoma ► Canine ► General info ► Also called spindle cell sarcoma Imesence ma. Tumors ► Group of tumors that are biologically si...

Soft Tissue Sarcoma / Osteosarcoma David Hunley, DVM, DACVIM (Oncology) Soft tissue sarcoma ► Canine ► General info ► Also called spindle cell sarcoma Imesence ma. Tumors ► Group of tumors that are biologically similar ► Same treatment and prognosis. D ► Arise from connective tissue, muscle, nerves, fat D ►Fibrosarcoma ► Nerve sheath tumor ► Rhabdomyosarcoma ► Leiomyosarcoma ► Liposarcoma ► Others Soft tissue sarcoma ► Canine ► General info Diendrus microscopica may D STAYBEHIND Durin Sure ► Locally invasive - - ISSUE PLE To Poss. MEGrouTH v ►Grow by “path of least resistance” ►- Low metastatic potential ►Depends on grade of tumor Soft tissue sarcoma ► Canine ► Typical presentation ► Firm subcutaneous mass ►Movable or fixed in place ► Found by owners or discovered on routine PE ► Generally not painful Soft tissue sarcoma ► Canine ► Testing ► FNA of mass ►Good enough for most cases, but… ►Sarcomas can be poorly-exfoliative ►Minimal characteristics of malignancy in many cases ►If confident in diagnosis, can go straight to surgery ► Biopsy ►Incisional/excisional (may depend on size of tumor) ►Usually get definitive answer ►Can assess for tumor grade Soft tissue sarcoma - SPREAD THRO BLOOD ► Canine ► Staging ► CBC/chem/UA ►Usually no significant abnormalities > - NORMAL ► Thoracic rads (3-view) b ►Lungs are most common place for tumor to metastasize P ↓ ►Tend to spread through blood vessels, not lymph nodes - CARCINOMAS ↓ ►Usually no metastasis seen with Grade 1 and 2 tumors Round Cl Amos D ►50% metastatic rate for Grade 3 tumors D Soft tissue sarcoma ► Canine ► Treatment ► Surgery ►Best treatment b b https://veteducation.com.au/soft-tissue-sarcoma/ ►Take wide and deep margins ►Generally curative if truly completely resected ►Maybe not Grade 3 ►Can’t trust narrow margins ►Many low grade soft tissue sarcomas do not grow back at the surgery site Soft tissue sarcoma ► Canine ► Treatment ► Radiation therapy ►Used when resection is incomplete ① ►Definitive radiation > Curative - usual ►Finely-fractionated: post-surgery ►Stereotactic: If gross disease is present come if surety INTAN OPTION ► Generally radioresistant ① ►Palliative radiation ►Slow growth of tumors (gross disease) ►Painful masses Soft tissue sarcoma ► Canine ► Treatment ► Systemic therapy > - NOTREALLY EY WESS THAN GRADE 1. ►Chemotherapy Antimon - D ►Carboplatin, doxorubicin for Grade 3 tumors A ► Used post-surgery ► Not usually helpful against gross disease 2 - ►Metronomic chemotherapy ►Used with gross disease or with incomplete resection ►Effectiveness is debatable Soft tissue sarcoma ► Canine ► Prognosis ► Long-term tumor control with complete resection ►Almost all Grade 1 and 2 tumors ►~50% of Grade 3 tumors ► ~75% long-term control of incompletely-resected tumors with surgery and radiation ►Similar with only surgery? ► When metastasis occurs, it is generally slow ►Median survival is around 1 year for high grade tumors  Soft tissue sarcoma ► Feline ► General info ► Spontaneous tumors uncommon ►Similar to canine ► Injection site sarcoma (ISS) > - DIFF To part. of Duet LOCATION ►Aka Vaccine-associated sarcoma (VAS) ►Mostly fibrosarcomas (can see osteosarcoma, chondrosarcoma) b D ►Initially found to be caused by adjuvant in vaccine (cats only) D ►Rabies, FeLV P ►We now use non-adjuvanted vaccines ►Much less frequent tumor formation  Soft tissue sarcoma ► Feline ► General info ► Injection site sarcoma (ISS) > - INTASALAR Armore ?? ►Can be caused by other repeated injections (Program, Depo-Medrol, antibiotics) D ►Aberrant inflammatory response (cats only) b ►Best to vaccinate on distal limb (tail?) ►Can amputate if tumor arises  Soft tissue sarcoma ► Feline ► Injection site sarcoma ► Typical presentation ►Firm subcutaneous mass ►Most commonly fixed in place ►Interscapular (where vaccines used to be https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6042530/ given) ►Distal limb (sometimes higher on limb ) ►Found by owners or discovered on routine PE ►Frequently causes pain/discomfort. More Cre To be paint - Soft tissue sarcoma ► Feline ► Injection site sarcoma ► Testing ► FNA of mass ►Good enough for most cases https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6042530/ ► Malignant mesenchymal cells ►If confident in diagnosis, can go straight to surgery ►Biopsy ►Usually incisional given invasiveness of mass ►May have clues that it was from injection/vaccine ► Inflammatory cells in tissue ► Vaccine adjuvant within macrophages  Soft tissue sarcoma ► Feline ► Injection site sarcoma ► Staging ►CBC/chem/UA ►Usually no significant abnormalities ►Maybe neutrophilia and mild anemia ►Thoracic rads (3-view) ►Lungs are most common place for tumor to metastasize (~25% metastatic rate) ►Abdominal US ►Occasional metastasis to abdominal viscera  Soft tissue sarcoma ► Feline ► Injection site sarcoma ► Staging ►CT scan https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6042530/ ►Tumor area if not on distal limb or tail ► Extent of tumor for surgical planning ► Often more invasive than it appears ►Thorax and abdomen ► To look for metastasis  Soft tissue sarcoma ► Feline ► Injection site sarcoma ► Treatment In ►Surgery ↑ ideque wide marins a ►Difficult to achieve wide margins on interscapular masses ►Amputation for limb/tail masses Z ►Post-surgical. radiation ►Definitive ► Always indicated given invasiveness of tumor ► Difficult to control even with radiation ►Palliative DSEEN A Or In stries  Soft tissue sarcoma ► Feline ► Injection site sarcoma ► Treatment ►Systemic therapy ►~25% metastatic rate, so reasonable to consider systemic therapy ►Chemotherapy (sume For suming ► Not very effective for gross disease (BIGmAssEs) D ► Carboplatin, doxorubicin, CCNU * (PLATINUM ACENT CANTOMORMEDs) Carkycatnanent ► I’ve seen best responses with CCNU (but still infrequent) ►Metronomic therapy ► Unknown effectiveness  - Soft tissue sarcoma - ► Feline ► Injection site sarcoma ► Prognosis ►Tumor tends to grow back regardless of therapy given https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6042530/ ►Usually in multiple spots on and around the surgery scar ►~18months with surgery, radiation, and chemotherapy ►Similar in some studies with surgery alone Osteosarcoma ► Canine ► General info ► Primary bone tumor ►Cell of origin: osteoblast ► Typically found in long bones ►Distal radius is most common - b►“Away from the elbow and towards the knee” & D► High metastatic rate D ►Maybe less in flat bones/axial skeleton ► More common in large/giant breed dogs P PHSKIES , ROTTO Osteosarcoma ► Canine ► Typical presentation ► Lameness ►May be acute or slowly progressive ►May have had transient/variable response to empiric pain meds (NSAIDs) ► Can have a hard painful mass in typical tumor location TRAMA CANCE O CAME D PMIMMAL ► Pathologic fracture  Osteosarcoma ► Canine & ► Testing - ► Radiographs of tumor site ►Bone lysis Aseness slims - ►“Moth eaten” area of bone ►“Sunburst pattern” of turn Bone sort ►Pathologic fracture - some WEAK FNA of mass 7 - ► Bones ►Possible since bone is weak in area of tumor ►Can see sarcoma cells ►Can sometimes make a definitive diagnosis of osteosarcoma https://www.acvs.org/small- animal/bone-tumors Osteosarcoma ► Canine ► Testing ► Biopsy ►Jamshidi biopsy tool https://www.cliniciansbrief.com/article/surgeons-corner-obtaining-bone-biopsy ►Surgery ►Not always diagnostic ►Normal bone (callous) often surrounds the tumor ►Frustrating for clients - Poss. CASE Bone Fractre Osteosarcoma ► Canine ► Staging promin ! comis por ► CBC/chem/UA- E ►Elevated ALP (worse prognosis) ►Possibly hypercalcemia (not common) ► Thoracic rads ►Lungs are most common metastatic site ►Also can metastasize to other bones and skin Osteosarcoma ► Canine ► Treatment D ► Amputation of affected limb D ►Best pain control D https://brambleberry-greyhounds.co.uk/tag/tripod/ micrometastati ►Does not prevent metastasis > - stre Luras Possible D2 in ► Chemotherapy ►Current treatment of choice is carboplatin (4- Alerts 6 doses) DPratimm ► Palliative radiation ►Second best pain control ►No significant effect on the tumor otherwise  Osteosarcoma ► Canine ► Treatment ► Bisphosphonates > - Th SUPERCAEMIA Too ►Zoledronate, pamidronate J Attach to hydroxyapatite receptors on bone ► and inhibit osteoclastic bone resorption n en wood ►Third ►May best pain control help improve bone density ► Definitive radiation ►Poorly-responsive to radiation ►May see benefit with stereotactic radiation Osteosarcoma ► Canine ► Treatment ► Oral pain medications ►NSAIDs D ►Gabapentin ►Tramadol ►Tylenol/codeine ►Least effective in pain control, but best for some clients ► Metronomic therapy ►Can be used in place of chemotherapy or as maintenance therapy after chemotherapy is completed How anowth ►Unclear effect on survival time Osteosarcoma ► Canine ► Prognosis ① ► Amputation alone ►Median survival: ~3-5 months ⑧ D► Amputation + carboplatin ►Median survival: ~12 months ③ ► Palliative radiation + carboplatin ►Median survival: ~7-8 months ►Risk of pathologic fracture if not amputated  Osteosarcoma ► Feline ► General info ► Same as for dogs except very low metastatic potential ►Amputation is often curative wow cas ! ►Don’t usually give chemotherapy https://tripawds.com/2022/06/08/osteosarcoma-metastasis-in-cats/ ►Newer info says that metastasis may not be as rare as we though D STOL poss. To metastasieD LOT HAREN A JUST DOESN'T Time for a break…