Splenic Lesions in Dogs: A Retrospective Epidemiological and Pathological Study

Splenic neoplastic and non-neoplastic lesions are frequently diagnosed in dogs and often exhibit overlapping clinical signs and gross morphological features, rendering histopathological examination essential for definitive diagnosis, therapeutic planning, and prognostic assessment. In Colombia, epidemiological data regarding these lesions remain limited, whereas international studies report considerable heterogeneity in the relative frequencies of neoplastic and non-neoplastic conditions. This study aimed to characterize the histopathological spectrum of splenic lesions in dogs and provide updated regional epidemiological data. A retrospective analysis was conducted on splenic specimens obtained from dogs subjected to total splenectomy between January 2019 and June 2024. All samples were processed and examined histopathologically at three veterinary pathology laboratories in Medellín, Colombia. Descriptive statistical analyses were performed considering year of submission, patient demographic data, morphological diagnosis, and concurrent histopathological findings. A total of 424 cases were evaluated, of which 282 (66.5%) corresponded to non-neoplastic lesions and 142 (33.5%) to neoplastic processes. The mean age of dogs with non-neoplastic lesions was 9.5 (< 1-16) years, whereas dogs with neoplastic lesions had a mean age of 10.2 (4-17) years. Splenitis was the most frequent non-neoplastic diagnosis, accounting for 54.6% of cases and demonstrating a higher prevalence than reported in prior literature. Among malignant splenic neoplasms, hemangiosarcoma was the predominant diagnosis, representing 69.2% of cases. This study demonstrates a high prevalence of non-neoplastic splenic lesions, particularly splenitis, and a frequent occurrence of multiple concurrent morphological diagnoses in non-neoplastic cases. These findings provide novel regional epidemiological data and contribute original information to international literature, underscoring the importance of histopathological splenic evaluation for accurate diagnosis and clinical decision-making.