강아지 비장 종양(혈관육종·결절성) 증상과 원인, 진단·치료와 관리 포인트 총정리

Canine Splenic Tumors (Hemangiosarcoma and Nodular Types): Symptoms, Causes, Diagnosis, Treatment, and Management Points

Oncology/CancerDiseasesMeongsiljang Veterinary Advisory Board

Canine splenic tumors (hemangiosarcoma and nodular types) are malignant growths that develop in the spleen. Early detection is crucial because they can cause acute hemorrhage and shock. Common signs include sudden collapse, abdominal distension, and anemia.

What Are Canine Splenic Tumors (Hemangiosarcoma and Nodular Types)?

The anatomical structure of a hemangiosarcoma tumor in the spleen

Among canine splenic tumors, hemangiosarcoma is a malignant tumor that originates from the vascular endothelial cells of the spleen. Approximately two-thirds of splenic masses are malignant, and about two-thirds of those malignant lesions are known to be hemangiosarcoma. It primarily affects middle-aged and older dogs, with a reported higher incidence in middle-aged German Shepherds. In contrast, benign nodular hyperplasia is also common in senior dogs, making differential diagnosis essential. In the early stages, symptoms are minimal, making early detection difficult. However, as the tumor grows or ruptures, it can cause intra-abdominal hemorrhage, leading to acute abdominal pain and shock. This is a life-threatening emergency, so regular health check-ups to monitor splenic health are crucial for middle-aged and older dogs.

What Are the Main Causes of Splenic Tumors?

The exact cause of splenic hemangiosarcoma remains unclear, but age and breed (genetic predisposition) are known to be significant risk factors. Studies have reported that breed classification based on genetic profiles can help predict malignant splenic lesions and hemangiosarcoma diagnoses, with middle-aged German Shepherds being particularly prone to the disease. Approximately two-thirds of splenic masses are malignant, and the majority of these are hemangiosarcomas. Although chronic inflammation, trauma, hormonal imbalances, and immune dysfunction have been suggested as contributing factors, there is currently insufficient evidence to confirm a specific causal relationship. The impact of living environment and diet has also not yet been proven. For early detection, regular check-ups, including abdominal ultrasounds, are recommended for middle-aged and senior dogs.

The spleen has developed multiple nodular tumors.

What Are the Main Symptoms of Canine Splenic Tumors?

Spleen tumors in dogs are often asymptomatic in the early stages, which can lead to delayed detection. However, as the tumor grows or ruptures, it can cause sudden bleeding and severe symptoms. Common signs include abdominal swelling, shock, decreased appetite, extreme weakness, difficulty breathing, and anemia. Sudden shock or loss of consciousness can be life-threatening and requires immediate veterinary care. The abdomen may also appear distended or show signs of pain when touched. Since these symptoms may not be visible externally until they develop, close observation is essential.

A dog in shock due to a ruptured splenic tumor

Symptoms Requiring Immediate Veterinary Care

If your pet suddenly experiences shock, difficulty breathing, loss of consciousness, severe weakness, or rapid abdominal swelling, seek veterinary care immediately. These symptoms may indicate acute bleeding from a ruptured splenic tumor, which can be life-threatening.

How Are Splenic Tumors Diagnosed?

Splenic tumors are often first suspected during an abdominal ultrasound examination. If the ultrasound reveals changes in the echogenicity or homogeneity of the splenic parenchyma, nodular lesions, hematomas, or masses, a tumor is suspected. A definitive diagnosis is made by collecting cells via ultrasound-guided fine-needle aspiration (FNA) or through histological examination of a tissue biopsy. Diagnosing poorly differentiated hemangiosarcoma can be challenging, so immunophenotyping for factor VIII-related antigen or CD31 is used to support the diagnosis. Splenic aspiration is also utilized as part of the tumor staging process. Signs of bleeding, such as anemia, are evaluated concurrently, and regular abdominal ultrasound screenings are helpful for early detection.

Ultrasound image showing a splenic tumor

How Are Splenic Tumors Treated?

The primary treatment for splenic tumors is surgical removal, known as a splenectomy. If the tumor has ruptured, immediate surgery is required, and activity must be restricted during the post-operative recovery period. It is important to combine surgery with chemotherapy to prevent metastasis. The choice of chemotherapy drugs depends on the tumor type and extent of metastasis, and your veterinarian will prescribe a regimen tailored to your dog’s individual condition. During treatment, side effects such as loss of appetite, nausea, and fatigue may occur, so close monitoring is essential. The treatment plan will be flexibly adjusted based on your dog’s environment and overall health status.

A puppy undergoing a splenectomy surgery

Home Care and Precautions

After surgery, it’s important to limit your pet’s activity and schedule regular check-ups. Feed small, frequent meals to maintain a balanced diet. During cancer treatment, watch for nausea, loss of appetite, and fatigue, as these are common side effects. If you notice abdominal pain or signs of shock, seek veterinary care immediately. Also, monitor the surgical site closely for swelling or signs of infection. Your consistent observation and daily records can greatly support your pet’s recovery. Regular check-ups help detect any recurrence early.

Home care for a puppy recovering from surgery

Breed-Specific Precautions and Recurrence Prevention

Middle-aged German Shepherds have been reported to be at high risk for splenic hemangiosarcoma. We recommend regular abdominal ultrasound screenings for middle-aged and senior dogs. Because splenic hemangiosarcoma has a high potential for metastasis, periodic check-ups and careful monitoring for any changes in symptoms are essential even after surgery.

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

Is a spleen tumor curable?

Combining surgery with chemotherapy can extend survival time in some cases. However, once the cancer has metastasized, a complete cure is unlikely, and long-term management will be necessary.

Which breeds are more commonly affected by splenic tumors?

Spleen hemangiosarcoma is reported to be most common in middle-aged German Shepherds. Additionally, approximately two-thirds of splenic masses are malignant, and of those, about two-thirds are hemangiosarcomas.

Can splenic tumors be prevented?

While there’s no foolproof way to prevent it, early detection through regular checkups significantly improves treatment success rates. Maintaining a healthy lifestyle also helps.

How long can my pet live after surgery?

When splenectomy is combined with adjuvant chemotherapy for splenic hemangiosarcoma, the median survival time has been reported to be approximately 141 to 179 days. However, there can be significant variation depending on the individual case.

What tests should be performed if a splenic tumor is suspected?

An abdominal ultrasound is the first recommended step. Following that, the tumor should be confirmed and staged through ultrasound-guided fine needle aspiration (FNA) or a tissue biopsy, with immunophenotyping performed if necessary.

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References

[1] Veterinary Surgical Oncology, 2nd Ed. (2019). Chapter 8: Splenic Tumors in Dogs. Elsevier.

[2] Textbook of Cardiovascular Medicine in Dogs and Cats. (2020). Section 13: Cardiac Hemangiosarcoma. Wiley-Blackwell.

[3] Clinical Medicine of the Dog and Cat, 4th Ed. (2018). Chapter 15: Hemangiosarcoma. Elsevier.