Hemorrhagic muscular metastasis of primary splenic hemangiosarcoma in a dog

This report describes the presentation and management of an incidental primary splenic hemangiosarcoma with hemorrhagic muscle metastasis following an incisional biopsy of a temporalis mass in a dog. In the absence of clinical signs related to the primary splenic lesion, skeletal muscle metastasis of hemangiosarcoma could be misdiagnosed as isolated primary tumor, resulting in failure to provide an accurate prognosis and effective treatment of the primary tumor itself. A thorough diagnostic imaging workup in patients presenting with blood-filled subcutaneous or muscular masses is fundamental to rule out a primary visceral hemangiosarcoma. In addition, the report describes the use of tranexamic acid as an effective local treatment for acute hemorrhage control from a musculoskeletal metastatic lesion that warrants further investigation. Key clinical message: The diagnosis and management of a multi-metastatic splenic hemangiosarcoma in a dog that was presented with hemorrhagic temporal muscle metastasis is reported. An alternative method to control acute hemorrhage using local tranexamic acid is described.