It is also important to provide the veterinarian with an accurate history of the dog's recent activities and behaviors. Work-up includes a complete blood count, chemistry panel, urinalysis and radiographs of the chest and abdomen. If available, ECG plus cardiac and abdominal ultrasound are very helpful. Diagnosis is accomplished by biopsy or removal of the tumor. This can be difficult because there may be multiple tumors present, the primary tumor site may prove challenging to determine, and there is great risk of severe hemorrhage.
Treatment includes surgical removal of the primary tumor followed by chemotherapy.
Various chemotherapy protocols exist which may include several drugs given in an exact order, including cyclophosphamide, vincristine, doxorubicin and cytoxan. Long-term prognosis of dogs with hemangiosarcoma is poor. Studies have shown that surgery alone, usually a splenectomy, offers a median survival time of 19-83 days. Dogs who have a primary tumor of the spleen without rupture of the blood vessel have a better prognosis. If the splenic tumor has ruptured, the prognosis is poorer.