Hemangiosarcoma in Pets

Cancer Series: November is Cancer Awareness Month for Pets

Hemangiosarcoma

                November marks National Pet Cancer Awareness Month.  To promote cancer awareness, we will discuss a different type of cancer affecting pets each week for this month.  This week, I will talk about hemangiosarcoma.

                Hemangiosarcoma is a fairly rare but deadly cancer that arises from blood vessels.  This tumor is most commonly found in the spleen, but may also affect the base of the heart, and, sometimes the skin.  German Shepherds, Golden Retrievers and Labrador Retrievers have the highest incidence of this type of tumor and it is most commonly diagnosed in older, large breed dogs.  This form of cancer has a poor prognosis, especially when found in the spleen or heart as it often rapidly metastasizes or spreads throughout the body.  Patton Veterinary Hospital sees a few cases each year. 

                Most dogs with hemangiosarcoma come to the vet because of weakness or collapse.  This occurs when the tumor ruptures and starts bleeding.  Internal bleeding into the abdomen or into the sac around the heart called the pericardium can cause anemia, low blood pressure and arrhythmias.  Sudden death due to massive and rapid blood loss may also occur. 

                Hemangiosarcoma can usually be diagnosed by radiographs (x-rays) or ultrasound but may also be suspected based on history, clinical signs like pale gums, abdominal distension, and with blood tests which may show a low red blood cell count (anemia) or by putting a needle through the body wall into the belly and finding blood within the abdomen. 

                Surgical removal of the spleen will remove the primary tumor and stop the bleeding, but it does not usually prevent spread or progression of the cancer, and survival times are typically only one to three months with surgery alone.  Heart based tumors may also be surgically removed, but the surgery is much more complex than removal of the spleen, and survival time is the same as with splenectomy—1 to 3 months.  Survival times may be extended slightly to four to eight months with surgery followed by chemotherapy. 

                The University of Pennsylvania School of Veterinary Medicine and other researchers are currently doing some clinical trial studying other treatments such as Chinese herbal medicines, immunotherapy and therapies to reduce the number of blood vessels produced by the tumor.  These studies may help us to better treat hemangiosarcoma and extend the lives of dogs affected by it

                A word about the cutaneous or “skin” form of hemangiosarcoma:  this form has a slightly better prognosis if completely removed and the cancer has not spread to other organs with survival times of six months or more. 

                Hemangiosarcomas are rare in cats, but we do find them occasionally. Tumors on or under the skin are more commonly found in cats than those in the spleen or heart.  They may also be found on the gums.  Sun exposure seems to be a risk factor for the skin form in both cats and dogs. 

                It’s not too late to join or support Patton Veterinary Hospital on Sunday, November 6^th as we participate in Gulliver’s Run which helps fund research and promotes awareness of all forms of canine cancer.  More information may be found at www.runagainstcaninecancer.org or www.wearethecure.org.  There is also a link on our web page.

                This blog brought to you by the Patton Veterinary Hospital serving Red Lion, York and the surrounding communities.