Spleen Tumours in Dogs: Symptoms, Diagnosis, and Treatment

What should you do when a spleen mass is found in your dog?

A spleen tumour in a dog requires prompt veterinary evaluation. Splenic masses range from benign blood-filled cysts to aggressive malignancies such as hemangiosarcoma. Early diagnosis — through imaging and blood work — determines whether surgery, supportive care, or further oncology assessment is the right next step. Timely action significantly affects outcomes.

MaxPetz in Delhi provides cancer care for pets, combining diagnostic imaging, surgical assessment, and compassionate post-operative support for dogs diagnosed with splenic masses.

What are the first signs of a spleen tumour in a dog?

Spleen tumours in dogs are often called a silent disease because early signs are subtle and easy to miss. As the mass grows — or if it begins to bleed internally — symptoms become more obvious and urgent.

• Lethargy and weakness — reduced energy or reluctance to exercise
• Pale or white gums — a sign of internal blood loss or anaemia
• Distended or swollen abdomen — caused by an enlarging spleen or internal bleeding
• Sudden collapse — often the first dramatic sign, indicating possible tumour rupture
• Reduced appetite or weight loss — common in progressive disease
• Rapid or laboured breathing — may indicate anaemia or fluid accumulation
• Intermittent vomiting — particularly after meals or physical activity

Dogs in the final stages of spleen cancer may show profound weakness, inability to stand, continuous internal bleeding, and unresponsiveness. At this stage, quality-of-life assessment with a veterinarian is essential.

What causes spleen tumours in dogs, and which breeds are at risk?

The exact cause of most splenic tumours is not fully understood. However, certain factors are consistently associated with higher incidence.

• Hemangiosarcoma — the most common malignant splenic tumour in dogs; arises from blood vessel cells within the spleen
• Nodular hyperplasia — a benign, age-related change that produces non-cancerous nodules; common in older dogs
• Hematoma — a blood-filled mass, usually benign, that can still rupture
• Other tumour types — including fibrosarcoma, leiomyosarcoma, and lymphoma

Breed and age are the strongest known risk factors:

How is a splenic mass diagnosed in dogs?

Diagnosis of a splenic mass in dogs typically involves a combination of physical examination, imaging, and laboratory tests. Definitive tumour typing usually requires histopathology after surgical removal.

1. Physical examination — a veterinarian may palpate an enlarged or irregular spleen during abdominal assessment
2. Abdominal ultrasound — the primary imaging tool; reveals the size, location, and internal structure of the mass, and detects free fluid (blood) in the abdomen
3. Chest X-ray — checks for metastatic spread to the lungs before surgery is considered
4. Complete blood count (CBC) and biochemistry panel — identifies anaemia, clotting abnormalities, and organ function status
5. Fine needle aspirate (FNA) — occasionally used, though results are often inconclusive for splenic masses due to sampling limitations
6. Histopathology — examination of the removed spleen under a microscope; the only way to confirm tumour type and malignancy

Because benign and malignant masses can look identical on ultrasound, surgery and histopathology are often required for a definitive answer. Approximately one-third of splenic masses in dogs are benign.

How is a spleen tumour treated in dogs, and should surgery always be considered?

Treatment depends on the tumour type, the dog's overall health, and whether the mass has ruptured or spread. Splenectomy — surgical removal of the spleen — is the most common intervention and is often recommended even before a definitive diagnosis, particularly in emergency situations involving internal bleeding.

• Emergency splenectomy — performed when the tumour has ruptured and the dog is in haemorrhagic shock; life-saving in the short term
• Elective splenectomy — planned removal of a detected mass; allows pre-operative stabilisation and reduces surgical risk
• Chemotherapy (adjuvant) — recommended after splenectomy for confirmed hemangiosarcoma to extend survival time
• Supportive care — blood transfusions, fluid therapy, and pain management for dogs not suitable for surgery
• Palliative management — for dogs with advanced or metastatic disease where surgery is not appropriate; focuses on comfort and quality of life

Dogs with benign splenic masses (such as hematoma or nodular hyperplasia) that undergo splenectomy generally have an excellent prognosis. Dogs with malignant hemangiosarcoma have a more guarded outlook; surgery alone extends median survival, and adjuvant chemotherapy may add further time.

For dogs whose owners are considering life expectancy without surgery: an unruptured benign mass may remain stable for months, but a malignant mass carries a significant risk of sudden rupture and rapid deterioration. A veterinary oncology consultation is strongly advised before deciding against surgery.

When should you bring your dog to a vet for a possible spleen problem?

Do not wait for symptoms to worsen. Seek veterinary attention promptly if your dog shows any of the following:

• Sudden collapse or inability to stand, even briefly
• Pale, white, or grey gums at any point
• A visibly swollen or tense abdomen that develops over hours or days
• Unexplained lethargy lasting more than 24–48 hours
• Rapid breathing at rest without obvious cause
• A known or suspected abdominal mass identified during a routine check-up

Older large-breed dogs — particularly those aged 8 years and above — should have routine abdominal ultrasound screening discussed with their veterinarian, even in the absence of symptoms, given the higher incidence of splenic disease in this group.

How does MaxPetz Delhi support dogs diagnosed with a splenic tumour?

MaxPetz in Delhi offers cancer care for pets using cutting-edge technology and a compassionate approach to treatment planning. When a splenic mass is detected, the team works through structured diagnostic assessment — imaging, laboratory evaluation, and surgical consultation — to give pet owners a clear picture of their dog's condition and the available options.

The focus at MaxPetz Delhi is on evidence-informed care: providing accurate diagnosis, honest prognosis, and a treatment plan aligned with both the dog's clinical needs and the family's circumstances. Post-operative monitoring and supportive oncology care are part of the service for dogs undergoing splenectomy.

To discuss your dog's symptoms or a recently identified splenic mass, use the booking form on this page to arrange a cancer care consultation with the MaxPetz Delhi veterinary team.