Splenic Tumours in Dogs: Welfare and Decision-Making
Overview of Splenic Masses
Splenic masses in dogs are relatively common, particularly in large and giant breeds over 8 years. The most important distinction is between haematoma (benign blood-filled cyst) and haemangiosarcoma (malignant vascular tumour). Roughly 50% of splenic masses are malignant. Other tumours include nodular hyperplasia, leiomyosarcoma, and lymphoma. The clinical challenge is that benign and malignant masses look similar on imaging and can only be definitively distinguished by histopathology.
Welfare Emergency: Haemoabdomen
Rupture of a splenic mass causing haemoabdomen (internal bleeding into the abdomen) is a welfare emergency. Affected dogs present with sudden collapse, pale mucous membranes, rapid heart rate, weakness, and abdominal distension. Without surgical intervention, they deteriorate and die within hours. Emergency splenectomy can be life-saving. Even in malignant cases, emergency surgery provides diagnostic information and may buy weeks to months of reasonable quality of life.
Diagnosis and Decision-Making
Abdominal ultrasound is the primary diagnostic tool, identifying splenic masses and free fluid. It cannot reliably distinguish benign from malignant masses. Three-view thoracic radiography and ultrasound assess for metastases. Blood tests assess surgical fitness. The 'rule of two-thirds' suggests roughly two-thirds of large splenic masses in dogs are malignant; two-thirds of malignant splenic masses are haemangiosarcoma. This informs but does not determine the decision to operate.
Treatment and Prognosis
Splenectomy (surgical removal of the spleen) is the treatment of choice for resectable masses. For haemangiosarcoma, median survival after surgery alone is 1-2 months; adjuvant chemotherapy (doxorubicin-based protocols) extends median survival to 3-6 months. For benign lesions (haematoma), splenectomy is curative. Owners need clear, honest information about prognosis to make welfare-centred decisions. Post-operative comfort and return to normal behaviour are welfare priorities.
Welfare in the Post-operative Period
Post-operative care includes pain management, monitoring for re-bleeding, and gradual return to activity. Dogs typically recover quickly from splenectomy. In cases of haemangiosarcoma, ongoing monitoring and quality-of-life assessment guides decisions about chemotherapy and, ultimately, timing of euthanasia. Clear communication between veterinary teams and owners about prognosis, treatment goals, and quality of life is essential for compassionate management.