Tumors of the spleen are fairly common in middle-aged to older dogs. The spleen is an organ located near the stomach, and is involved in regulating blood cells. This organ is most important in very young animals; luckily, it can be safely removed in older animals with little impact on the individual's health. Tumors of the spleen are most often found during a physical exam when the veterinarian palpates the dog's abdomen. These tumors can grow very quickly, and become very large.

One of the most common types of splenic tumor is the hemangiosarcoma. This is a serious, malignant type of cancer. However, if caught early enough, removal of the spleen can give the dog improved comfort and possibly a longer life span. Another common type of splenic tumor is a hemangioma, which is a benign cancer, and removal of the spleen is curative. It is not possible to know which tumor the dog has prior to surgery, so after screening tests to check for any possible cancer spread, surgery is recommended for any dog with a splenic tumor.

After surgery, the patient is at an increased risk of a heart irregularity for the first few days. Once this period is passed, the patient ususally recovers quickly and returns to an excellent quality of life. In this case, surgery was performed on a 14 year-old English setter dog, Commander, with a 6 1/2 pound tumor on the spleen. Prior to surgery Commander was in considerable pain, couldn't eat and was very lethargic. After surgery he returned to his regular walks, and went back to bossing around the other dogs in the house.