Splenic Nodules and Masses

This examination evaluates primary splenic masses and nodules in dogs and cats, focusing on their diverse behaviors and diagnostic challenges. Key conditions include hemangiosarcoma, histiocytic sarcoma, lymphoma, and benign/malignant tumors. Many splenic masses are malignant, with poor survival post-splenectomy, though some, like splenic marginal zone lymphoma and hemangioma, may have better prognoses. Ultrasonography and cytology are explored, with emphasis on their limitations and potential misinterpretation. The Tufts Splenic Tumor Assessment Tool (TSTAT) is introduced as a decision-support calculator to estimate malignancy probability, aiding clinical decisions and reducing inappropriate euthanasia. The chapter evaluates multivariable calculators, such as TSTAT and the hemangiosarcoma likelihood prediction (HeLP) score, which utilize clinical variables and diagnostic data to inform treatment. In cats, splenic neoplasia is rare, with hemangiosarcoma and mast cell tumors being prevalent. Cytology may not always be accurate, and histopathology remains the gold standard. The study underscores the importance of integrating clinical findings, imaging, and diagnostic data for informed decision-making. Emerging tools aim to personalize treatment and reduce unnecessary euthanasia, though further refinement and validation are needed to enhance preoperative diagnostic accuracy in veterinary medicine.