This article was updated on December 5th, 2022
As an emergency veterinarian, there is a very classic presentation I see on a weekly basis. An older, large breed dog will present to my hospital with a sudden history of collapse, weakness, lethargy, or just not doing right at home. I generally can take one look at these dogs and know right away what the underlying diagnosis is. Pale gums, distended abdomen, and a firm mass effect on abdominal palpation and the answer is pretty apparent.
I will use a bedside ultrasound machine to screen the belly, which will generally show free fluid and a mass effect in the upper abdomen. A quick sample of this fluid will demonstrate hemorrhagic (bloody) effusion. My fears have been confirmed. This dog has a hemoabdomen, likely from a bleeding splenic tumor.
Splenic tumors are unfortunately very common in older animals. These tumors may be benign or malignant, but there is no way of knowing without taking the tumor out. This means that owners have to commit to surgery before obtaining an official diagnosis.
Many of these tumors will grow over time but are not diagnosed until the dog shows clinical signs of bleeding. These signs often come on suddenly. Affected dogs may be fine one moment, then the next moment, they are weak and unable to stand. It is a sad diagnosis to have to break to owners, especially because statistically these tumors are caused by an aggressive cancer called hemangiosarcoma.
How Will a Splenic Tumor Affect My Dog?
Splenic tumors are often not diagnosed until they begin bleeding or are diagnosed incidentally. These tumors can grow quickly or slowly depending on the underlying cause. Many dogs will be unaffected when the tumors are small or are not bleeding. Some dogs may be lethargic or have abdominal discomfort secondary to the stretch of the capsule of the spleen as the mass grows in size. If the mass is malignant in origin, dogs may overall feel unwell due to the inflammation caused by cancer. Some dogs will lose weight and have a decreased appetite. Waxing and waning weakness is also an insidious sign.
Here are the most common clinical signs demonstrated by dogs with splenic tumors:
- Abdominal distension
- Abdominal pain
- Generalized weakness
- Poor appetite and potential weight loss
- Pale gums
- Labored breathing
While some of these clinical signs may be subtle, if a tumor bleeds suddenly, dogs can become extremely weak. Some dogs can have a severe rupture of the mass leading to the point of passing away suddenly from blood loss. This is why it is so important for owners to monitor their dogs diligently, especially if it is known that they have a splenic tumor.
How Will the Vet Treat a Splenic Tumor?
After a splenic tumor has been diagnosed, either by abdominal radiographs or ultrasound, your veterinarian will come up with a comprehensive treatment plan. Splenectomy (surgery to remove the spleen) is the number one recommendation. This is performed not only to stop the bleeding but also to remove the mass for an official diagnosis. Before surgery, many dogs may need stabilization, especially if they are actively bleeding. Often we will give dogs intravenous fluids, pain medication, and antiarrhythmics if they are showing abnormalities on their ECG. If they are not able to be stabilized with fluids alone, many dogs will need a blood transfusion to combat anemia caused by the sudden bleed. Medications may be given to help try to slow or prevent further bleeding.
If you elect not to take your dog to surgery, your veterinarian will discuss your options. Dogs that are critically ill may sadly require euthanasia. If your pet is stable or can be stabilized, we will often send them home with medication to slow/prevent bleeding.
Can Dogs Survive a Splenic Tumor Without Treatment?
Without splenectomy, many tumors will continue to bleed, leading to life-threatening anemia. The timeframe of when this will occur is unpredictable and can occur within days to weeks to months.
If your dog has hemangiosarcoma, survival is generally only one to two weeks, with death occurring secondary to severe bleeding. Some dogs may live for months, but this is atypical (Source: Today’s Veterinary Practice).
What is the Life Expectancy With Splenic Tumor Treatment?
The most frustrating thing about splenic tumors is that an underlying diagnosis cannot be made without removing the spleen and submitting it for histopathology. This allows a pathologist to look at the tumor cells and determine if they are malignant or benign in origin.
Dogs who have undergone splenectomy and have been diagnosed with benign tumors are often cured. They can live a normal lifespan after recovery.
Dogs diagnosed with hemangiosarcoma who have undergone splenectomy, but not chemotherapy will live for one to three months. With chemotherapy, dogs can live for six months with 10% of dogs living up to a year (Source: CSU Animal Cancer Care Center).
Does Life Expectancy & Survival Rate Vary by Splenic Tumor Stage?
The stage does influence survival. Visceral hemangiosarcoma is divided into three stages
- Stage I: Tumor smaller than 5cm with no evidence of metastasis. Dogs with Stage I disease have a median survival of 5.5 months.
- Stage II: Tumor >5cm, ruptured tumors with regional metastasis, but no distant metastatic disease. Dogs with Stage II disease have a median survival of 2 months
- Stage III: Tumor >5cm, ruptured and has invaded adjacent structures or has distant metastatic disease. Dogs with Stage III disease have a median survival of less than 1 month. Splenectomy is often not recommended with Stage III disease given the grave prognosis (Source: Clinician’s Brief).
How Can I Make My Dog’s Life Better When My Dog Has a Splenic Tumor?
Many dogs with Stage I disease will not know they have a tumor at all. They may experience intermittent discomfort, so you should discuss a pain control regimen with your veterinarian. Dogs with more advanced disease may have limited time as bleeding can occur at any moment. It is important to ensure they do not experience any trauma that could cause a splenic mass to rupture. Some of them may have a decreased appetite or lose weight, so it is important to offer them their favorite foods or give them an appetite stimulant.
Medications to slow bleeding can be purchased from your veterinarian. We most commonly use Yunnan Bayou or aminocaproic acid. These should be given daily, but it is controversial as to whether they improve survival time or not. Discuss palliative care with your veterinarian to ensure your dog is as comfortable as possible.
Disclaimer: This content is not a substitute for veterinary care. Always consult with your vet for health decisions. Learn more.
Are Most Splenic Tumors Cancerous in Dogs?
Unfortunately, yes. Of dogs that have splenic tumors, 2/3 to 3/4 of them will be cancerous with hemangiosarcoma being the most common form of cancer.
How Common are Splenic Tumors for Dogs?
Splenic tumors are very common in older animals whether benign or malignant.
What Breeds are Most Likely to Have Splenic Tumors?
Large breed dogs are at an increased risk. This is especially true for German Shepherds, Golden Retrievers, Labradors, and Poodles. It is important to remember that any dog can develop a splenic tumor.
Can a Dog Live a Normal Life without a Spleen?
Yes! Dogs do not need their spleens to live normal lives.
Should I Have My Dog’s Spleen Removed?
If you wish to control the source of bleeding and offer your dog the best chance at survival, then the answer is yes. Without performing a splenectomy, the mass may cause life-threatening bleeding at any time. Performing surgery will allow the mass to be removed, the bleeding to be controlled, and an official diagnosis to be made. This will also help guide future treatments if needed.