Risk Factors and Outcomes of Splenectomy in Dogs with Splenic Masses at Nigerian Veterinary Teaching Hospitals

Splenic masses in dogs, ranging from hematoma and nodular hyperplasia to malignant hemangiosarcoma, are a common indication for splenectomy and represent a surgical oncology challenge requiring both accurate preoperative characterization and risk-stratified surgical management. This analytical study evaluates risk factors, perioperative parameters, histopathological findings, and survival outcomes following splenectomy for splenic masses in dogs at teaching hospitals in the South West, South South, and North Central geopolitical zones of Nigeria from 2021 to 2024. Seventy-one dogs undergoing splenectomy for splenic masses were prospectively enrolled. Preoperative ultrasonographic assessment, tumor-to-normal parenchyma ratio, and hematological indices were recorded. Risk factors for intraoperative hemorrhage and postoperative complications were identified by multivariate analysis. Malignant histopathological diagnosis, predominantly hemangiosarcoma, was confirmed in 47% of excised spleens. Benign lesions including hematoma and nodular hyperplasia comprised 53%. Preoperative ultrasonographic appearance correctly predicted malignancy in 68% of cases, with heterogeneous cavitary lesions most strongly associated with hemangiosarcoma. Intraoperative hemorrhage requiring blood transfusion occurred in 24% of malignant cases. Median survival following splenectomy for hemangiosarcoma was 60 days, compared to 420 days for benign mass resection. Preoperative packed cell volume below 25% was the strongest independent risk factor for intraoperative mortality. These findings provide the first multi-center analytical dataset on canine splenectomy outcomes in Nigeria, supporting refined preoperative risk stratification and surgical consent protocols. Keywords: splenectomy, splenic mass, canine, hemangiosarcoma, surgical outcomes.