Figure 3: Fine-needle aspirate of an intra-abdominal mass in a young dog. Mildly pleomorphic round cells containing low numbers of vacuoles and one cell with a single large vacuole are present. These cells occasionally formed loose aggregates as seen here. The primary differential diagnosis was neoplasia (histiocytic sarcoma, other sarcomas, or atypical lymphoma). Wright’s—Giemsa stain, 100x objective, bar = 20 μm.