Understanding Hemangiosarcoma in Dogs: Treatment Options and Prognosis

Hemangiosarcoma is an aggressive, malignant tumor derived from blood vessel cells that grows rapidly, can cause severe bleeding, and has a high metastasis rate. It most commonly affects the spleen but can also occur in the heart, skin, and liver, with certain breeds like German Shepherds, Golden Retrievers, and Labradors at higher risk. Treatment typically involves surgical removal followed by chemotherapy, though targeted therapies and supplemental approaches like metronomic therapy and mushroom extracts are showing promise. Despite aggressive conventional treatment, prognosis remains guarded, with median survival ranging from 1-7 months depending on tumor location and whether chemotherapy is pursued after surgery.

Treatment Options

The most common treatment approach often involves complete surgical removal, when possible, followed by injectable chemotherapy. Adriamycin (doxorubicin) is an injectable chemotherapy that is commonly used for lesions associated with a high rate of metastasis. This chemotherapy regimen is generally well-tolerated, with patients experiencing minimal side effects. Potential side effects may include lethargy, decreased appetite, vomiting, diarrhea, and decreases in white blood cell and platelet counts.

Despite aggressive conventional therapy, poor prognoses have driven interest in additional options such as targeted therapies. Fortunately, FidoCure enables access to targeted therapies that may help hemangiosarcoma patients by targeting cells with common mutations in genes like TP53, Ras, and PTEN. These targeted therapies more selectively inhibit cancer cells with these mutations. Depending on the clinical circumstances, these treatments have been used with traditional therapy or in place of injectable chemotherapy.

Preliminary data from FidoCure® reveals that dogs treated with traditional chemotherapy and targeted therapy after surgery had a greater median overall survival than those treated with only chemotherapy following surgery.

Three additional therapeutic approaches are showing promise in managing this disease. Oral metronomic therapy is used to reduce blood vessel growth in a tumor, in turn delaying tumor progression and metastasis. Treatment involves daily administration of low-dose chemotherapy combined with a non-steroidal anti-inflammatory drug. Another approach involves a Chinese herbal remedy called Yunnan Baiyao, which has potential anti-cancer effects against hemangiosarcoma. The third approach involves a Coriolus mushroom supplement called Im'Yunity, which has exhibited benefits in dogs with splenic hemangiosarcoma.


For dogs with primary splenic hemangiosarcoma, the median survival following surgery alone is 1-3 months. However, when surgery is followed with injectable chemotherapy, life expectancy increases to about 5-7 months. In cases where hemangiosarcoma occurs primarily in the heart, life expectancy is 3-6 months as surgery is limited due to the location of the tumor. On the other hand, if hemangiosarcoma occurs in the skin, life expectancy can vary depending on the depth and extent of the disease. 

For the most accurate prognosis and treatment recommendations for your dog with hemangiosarcoma, consult your veterinarian or a veterinary oncologist. They can provide personalized guidance based on your dog's specific case, considering factors such as cancer stage, grade, tumor location, and concurrent health issues.