강아지 비장 종양(혈관육종·결절성) 자주 묻는 질문 Q&A — 보호자가 꼭 알아야 할 핵심

What Are Spleen Tumors in Dogs? — Differences Between Hemangiosarcoma and Nodular Types and Treatment Approaches

Oncology/CancerQ&AMeongsiljang Veterinary Advisory Board

Spleen tumors in dogs can be life-threatening due to sudden, severe bleeding if not detected early. Here’s the essential information every pet owner should know.

What Are Splenic Tumors (Hemangiosarcoma and Nodular Types) in Dogs?

An illustration showing the enlargement of a malignant tumor in the spleen.

Splenic tumors in dogs, such as hemangiosarcoma and nodular types, are malignant growths that originate from the blood vessels or mesenchymal cells of the spleen. These tumors are most commonly seen in middle-aged to senior dogs, with certain breeds like German Shepherds being at higher risk for visceral (splenic or cardiac) hemangiosarcoma. If not detected early, tumor rupture can lead to life-threatening acute intra-abdominal hemorrhage. - Decreased splenic function: The spleen plays a key role in blood filtration and immune response, but tumor development can impair its normal function. - Increased risk of bleeding: Tumor rupture can cause sudden internal bleeding in the abdomen, potentially leading to shock. - Early detection is crucial: Since early-stage tumors often show few or no symptoms, regular veterinary check-ups are essential. - Diagnostic methods: Diagnosis is typically confirmed through abdominal ultrasound, blood tests, and if necessary, fine-needle aspiration (FNA) or tissue biopsy. Immunophenotyping markers such as factor VIII and CD31 may also support the diagnosis. A thorough evaluation by a veterinarian is essential for accurate diagnosis.

What Are the Main Causes of Splenic Tumors?

While the exact cause of splenic tumors remains unclear, certain breeds are known to be predisposed. German Shepherds, for instance, are widely recognized as having a higher risk of developing visceral hemangiosarcoma. - Age-related factors: These tumors primarily occur in middle-aged to senior dogs, with the average age of onset for canine hemangiosarcoma reported at approximately 9.6 years. - Variety of splenic lesions: In older dogs, benign nodular hyperplasia is just as common as malignant tumors. - Breed predisposition: Some breeds, such as German Shepherds, are reported to be genetically more susceptible to visceral hemangiosarcoma. - Malignancy rate: According to the textbook "Rule of Two-Thirds," about two-thirds of splenic masses are malignant, and of those malignant cases, roughly two-thirds are confirmed to be hemangiosarcoma. Therefore, precise diagnosis is essential when a splenic mass is detected.

The process of cancer cells developing in splenic tissue, in a microscopic image style

What Are the Main Symptoms of Splenic Tumors?

Spleen tumors in dogs often show few or no symptoms in the early stages. However, as the tumor grows or begins to bleed, the following signs may appear: - Sudden shock: Symptoms such as fainting or difficulty breathing may occur. - Abdominal distension: The abdomen becomes noticeably swollen due to an enlarged spleen. - Loss of appetite: The dog may suddenly refuse food or experience a sharp decline in appetite. - Fatigue and lethargy: The dog may remain inactive and lie down for most of the day. - Signs of anemia: The lips and oral mucosa become pale, and breathing becomes rapid. If you notice any of these symptoms, seek veterinary care immediately.

A dog suspected of having a splenic tumor, with pale lips and a swollen abdomen.

Signs Requiring Immediate Veterinary Visit

If your pet suddenly faints or has trouble breathing, take them to the vet immediately. This could be shock caused by acute bleeding from a spleen tumor. If their abdomen swells rapidly or they completely lose their appetite, they should be seen by a vet within 24 hours.

How Are Splenic Tumors Diagnosed?

Spleen tumors can often be suspected first through an abdominal ultrasound. - Ultrasound examination: This helps assess the size, shape, and internal structure of the spleen to determine if a tumor is present. - Blood tests: These may reveal anemia, low platelet counts, or elevated inflammatory markers. - Biopsy for confirmation: If a tumor is suspected, a tissue biopsy or surgical examination is performed to make an accurate diagnosis. - Imaging as a supplement: CT or MRI scans may be used in more complex cases. - Importance of regular check-ups: Even if there are no symptoms, it's recommended to have check-ups every 6 months to a year. According to veterinary internal medicine textbooks, ultrasound is the first step in diagnosing spleen abnormalities.

Ultrasound image showing a tumor in the spleen, medical image

What Are the Treatment Options for Splenic Tumors?

The primary treatment for splenic tumors is splenectomy, the surgical removal of the spleen. Removing the affected spleen eliminates the risk of bleeding and can extend survival time. Postoperative chemotherapy may be administered, depending on the tumor type and whether metastasis has occurred. In some cases, surgery may not be feasible, so a veterinarian will evaluate the pet’s overall condition. Recovery after surgery typically takes about one to two weeks.

A puppy recovering from a spleen removal surgery in a hospital setting

How Long Is the Survival Period After Surgery for Splenic Tumors?

The survival period after surgery for a splenic tumor varies significantly depending on the type of tumor and whether it has metastasized. For splenic hemangiosarcoma, the reported median survival time when splenectomy is combined with adjunctive chemotherapy is approximately 141 to 179 days. If metastasis is confirmed, the survival period may be even shorter. On the other hand, one study found that in small dogs weighing 20 kg or less, there was no significant difference in survival time after splenectomy for hemangiosarcoma compared to large dogs receiving the same treatment over the same period. Therefore, post-surgical evaluation of the tumor type and regular follow-up examinations are essential.

Survival time graph after splenic tumor surgery, information visualization

Comparison of Splenic Tumor Treatment Options

Item	Timing of application	Effect	Side effects
Splenectomy	When diagnosed early	High	May extend survival time
Chemotherapy	After surgery or upon metastasis	Moderate	May suppress metastasis
Conservative management	When surgery is not possible or in old age	Low	Focused on symptom relief

The treatment choice depends on the stage of the tumor and the dog's overall health condition.

Note: Postoperative Care Is Important

For the first one to two weeks after surgery, limit your pet’s activity and keep their environment clean to prevent infection. Offer small, frequent meals and closely monitor for signs of abdominal swelling or bleeding. It is essential to administer all medications prescribed by your veterinarian. Inadequate care can lead to recurrence or complications.

Reviewed by a veterinarian

Dr. Tony — Punnawat Phongkittirak

Veterinarian

A veterinarian who majored in veterinary medicine at Khon Kaen University, Thailand, and completed the IVSA program at North Carolina State University in the United States. Drawing on clinical experience at animal hospitals, he works in the pet healthcare field and is dedicated to building a digital care environment that connects pet parents with veterinarians.

Frequently Asked Questions

Can a spleen tumor be cured?

Spleen tumors can lead to a longer survival time if detected early and completely removed through surgery. However, if metastasis occurs, a complete cure becomes difficult, and long-term management is necessary.

Which breeds are more commonly affected by splenic tumors?

Visceral (splenic) hemangiosarcoma is known to carry a particularly high risk in German Shepherds. Genetic predisposition by breed plays a role, and it primarily occurs in middle-aged to senior dogs.

Can spleen tumors be prevented?

While there’s no definitive way to prevent it, early detection through regular abdominal ultrasounds significantly improves treatment outcomes. We especially recommend routine check-ups for middle-aged and senior dogs.

How often does a splenic tumor recur after surgery?

Splenic hemangiosarcoma is a tumor that frequently metastasizes, so there is a risk of recurrence or metastasis even after surgery. Even with adjuvant chemotherapy, the average survival time is reported to be approximately 141 to 179 days, making regular follow-up examinations essential.

If a splenic tumor is suspected, what tests should be performed?

An abdominal ultrasound is the first recommended test. If needed, additional tests such as blood work, fine-needle aspiration (FNA), tissue biopsy, CT, or MRI may be performed. Early diagnosis improves the chances of successful treatment.

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References

[1] Hosgood, G. et al. (2019) Veterinary Surgical Oncology, 2nd Ed. Wiley-Blackwell.

[2] Plumb's Veterinary Drug Handbook, 9th Ed. (2022). Wiley-Blackwell.

[3] Textbook of Cardiovascular Medicine in Dogs and Cats (2021). Elsevier.