Comparative cytology and histology in canine and feline gastrointestinal neoplasia: advantages and challenges

This article evaluates advantages and disadvantages of cytology and histology of gastrointestinal (GI) neoplasia, from sampling to diagnosis. Available cytological and histological sampling techniques for the GI tract are summarized and discussed. The most common GI neoplasias are then described from both a cytological and histological point of view, highlighting the strengths and weaknesses of each technique and suggesting additional tests when appropriate. Understanding of the diagnostic process will help guide the clinician in the investigative process.