Cancer in pets

Dear Anke,

The first thing you should know about cancer in a dog’s spleen is that it is unfortunately usually serious, and in most cases, even if the spleen is removed, dogs don’t usually live more than a year.  The most common cancer that is found on the spleen is called Haemangiosarcoma. It is a cancer that forms from the tissue that normally would help to form veins and arteries.  The dogs that usually get these cancers are German Shepherd dogs, usually about ten years of age and often are female.

German Shepherds are prone to cancer in the spleen.

It is called “the silent killer” because 9 times out of 10, the tumor bursts inside the dog’s body and an apparently perfectly healthy dog collapses with an abdomen full of blood. Once the cancer has burst, there is a good chance that it has “seeded” – in other words, that little cancer cells have spread themselves everywhere inside the abdomen of the dog. If the spleen is removed at this point, it will save the dog’s life temporarily (for about three months) until the new tumors have again grown to a size where they will burst and bleed out inside the dog. If chemotherapy is used, it can delay the regrowth of these tumors a little, but they usually grow back.  If the cancer on your dog’s spleen was picked up before it burst and bled out, then your dog has a  much better chance of survival than she would have had after it seeded.

Hemangiosarcomas growing in the spleen

Growths or cancers can be picked up if a dog goes in for an ultrasound exam and sometimes by feeling your dog’s abdomen during clinical examination.  Sometimes doing blood tests will also pick up if there is cancer in her body as there may be changes in the cell counts as well as elevations in some enzymes released from organs such as the liver.  If Haemangiosarcoma has been picked up before it bursts, then it is important to have an ultrasound examination of your dog’s other organs, especially her liver and heart, as the cancer can also spread to those organs prior to it bursting.  If nothing is seen on ultrasound exam, most veterinarians will give the owner the option to remove the spleen and double check the other organs at the same time.

The reason for this double checking is that tiny areas of cancer that have spread may be too small to be picked up by a scanner but can be seen by the human eye.   If nothing else is seen, your vet can safely remove her spleen and send it for biopsy to determine if a growth on the spleen is malignant(cancerous) or benign.  Your dog is able to survive without her spleen, but if you live in an area where you get ticks that carry diseases like tick bite fever (Canine Babesiosis) then without her spleen, she would be much more susceptible to this disease.  So your dog’s long term health really depends on what stage the cancer was in when it was picked up and also if the biopsy showed it to be malignant or benign.

Haemangiosarcoma in the Heart of the Dog