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Dog Spleens

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small white and tan dog with red collar sitting on the floor with tongue hanging out

The canine spleen is the largest of their lymphatic organs—close to the size of the dog’s forearm. This means that the measurement for the spleen can vary from one pup to the next. These organs are roughly shaped like a boomerang and are dark red or purple in color. Spleens can help remove old red blood cells, bacteria, and foreign proteins, create new red blood cells, store red blood cells and platelets, and fight infections. Although this organ serves multiple purposes, dogs can have their spleens removed with little to no effect on their everyday lives.

Where Is a Dog's Spleen Located?

A dog’s spleen is located in the upper left section of their abdomen. It is attached to their stomach via tiny blood vessels and a thin layer of tissue. When looking at your dog’s profile, if you follow about halfway down their spine, you will have the rough placement of this organ tucked behind their ribs.

Splenomegaly, the enlargement of the spleen, is relatively common in canines. It can affect a dog of any age, size, or breed and become a serious condition. Symptoms of an enlarged spleen in dogs include loss of appetite, lethargy, pale gums, panting, quickened heart rate, sudden weakness, and an enlarged abdomen. Your dog's exact symptoms will depend on how enlarged their spleen becomes.

There are a few causes of an enlarged spleen, such as liver, stomach, or intestine infections, inflammation from inflammatory bowel disease (IBD), and tumors. Serious abdominal injuries can also lead to an enlarged spleen. When an injury is severe enough, such as a dog getting hit by a car or kicked by a horse or trauma caused by cancer or a tumor, this could lead to a ruptured spleen in a dog. Once this occurs, the canine’s condition will instantly become more serious. A ruptured spleen can be life-threatening, so it is crucial to receive a diagnosis and begin treatment as soon as possible.

If you suspect your dog’s spleen has been affected, it’s crucial that you take them to their veterinarian right away for a proper diagnosis, which may include a physical exam, X-rays, bloodwork, and an ultrasound. Depending on how serious your dog’s condition has become, it’s possible for your veterinarian to feel the enlarged spleen with just a hands-on examination. Treatment will depend on your dog’s condition and the cause of their enlarged or ruptured spleen. Some cases can easily be managed with medications, but with more severe scenarios, canine spleen removal by surgery is typically the way to go.

The surgical removal of the spleen, known as a splenectomy, is a common procedure that most dogs handle very well. And while any time your dog has surgery and goes under anesthesia it should be taken seriously, pet parents should rest assured that the risk versus reward for this procedure is often favorable. In fact, once a dog’s spleen is removed, they are virtually unaffected, and their quality of life can often improve—especially if the spleen was the location of their cancer or tumor.

Recovery time from this surgery is rather quick, and dogs bounce back faster than people when they have their spleens removed. That said, be sure you follow all post-operative instructions given by your veterinarian since this can help lead your pup to a successful recovery.

Spleen Cancer in Dogs

Dogs of any age can be diagnosed with spleen cancer or spleen tumors, but the risk may increase as a dog gets older. Medium to larger-sized dogs may also have an increased chance of developing a tumor in their spleen. This may include breeds such as German Shepherds, Golden Retrievers, and Labrador Retrievers. Tumors can be categorized into a few different types:

  • Benign (non-cancerous)

  • Malignant (cancerous)

  • Primary (originated in the spleen)

  • Secondary (spread from another tumor, not in the spleen)

  • Focal (focused in one area)

  • Diffuse (spread throughout the whole organ)

Although genetic predispositions can cause a canine to have these types of tumors, the exact cause remains unknown in many instances.

It’s important to note that since there are several types of tumors that a dog can develop in their spleen, the symptoms diagnosing techniques, and treatment options may all vary based on the specific tumor a canine has.

Symptoms of Spleen Cancer in Dogs

There are many signs a dog can display if they have a splenic tumor. However, it is not unusual for the condition to go unnoticed for some time since symptoms can remain minor or undetectable. In fact, a dog’s tumor or cancer will often be caught when a dog is at their veterinarian for another reason or during a routine exam. If the spleen ruptures and bleeding quickens, this is when symptoms can present themselves more drastically. These can include:

  • Weakness

  • Lethargy

  • Collapse

  • Pale gums

  • Decreased appetite

  • Irregular heartbeat

  • Cold limbs

  • Bloating or swelling in the abdomen

If you notice any of these symptoms, it’s crucial that you take your best pal to their veterinarian as soon as possible. In addition to a physical examination, your veterinarian may also recommend bloodwork, an X-ray, an ultrasound, or a biopsy to have an accurate diagnosis.

In many cases, surgery can be the best form of treatment. Not only can this help remove the entire tumor, but it also eliminates the worry of the spleen rupturing. Depending on your dog’s type of tumor, chemotherapy may also be recommended post-surgery. If your best pal is not an ideal candidate for surgery, medication may be the better treatment. Keep in mind, in some cases, medication will not cure your dog but will instead help improve their quality of life.

It's worthwhile to understand the nuances between treatment and a cure. When something is curable or has a cure, the health issue can be resolved with zero remnants left behind. For instance, surgery is a cure for some splenic tumors since it can completely remove the entire tumor, leaving none in the body. However, with treatment, this may be referring more toward managing a health condition’s symptoms, though the issue still remains.

How To Prevent Spleen Cancer in Dogs

Unfortunately, there is no prevention method for spleen cancer in dogs. One of the best things you can do for your pup, in terms of looking out for their health, is to continue taking them to their annual veterinary appointments. During these routine check-ups, your veterinarian will have a higher chance of catching any medical issues earlier on, compared to how far a condition could progress if you went years in between appointments.

Preventive care should be made an essential part of your dog’s routine. By taking these extra measures, you can rest assured knowing that you took the extra step to provide your pup with the care they need.

An ASPCA® Pet Health Insurance plan can help you with eligible costs for covered conditions like surgery expenses for accidents and help provide peace of mind that your pet can receive the care they need. Check out our online resources to learn more about your insurance options and get a free quote today. The information presented in this article is for educational and informational purposes only and does not constitute or substitute for the advice of your veterinarian.

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