“…Accounting for 1% of all osteosarcoma cases, exOSA can occur in a variety of organs [ 6 ]. Cases of canine exOSA involving the gastrointestinal tract, subcutaneous tissue, spleen, urinary tract, liver, mediastinum, skin, muscle, eyes, central nervous system, omentum, pericardium, and thyroid gland have been reported [ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 ]. Additionally, exOSA tends to affect older dogs more frequently than skeletal osteosarcoma, although no predispositions regarding dog size have been reported [ 6 , 7 ].…”