Abstract
Cytology of gastro-intestinal (GI) tract lesions can be used successfully to diagnose neoplastic and non-neoplastic conditions, especially when combined with biopsies. Cytologic evaluation is widely accepted as a cost-effective method that allows rapid interpretation and triaging of material. Technical advances over the years have allowed simultaneous visualization of abnormal tissue and procurement of needle aspirates, brushings and biopsies from mucosal and deeper seated lesions. Successful cytologic examination of the GI tract is highly dependent on the skill of the endoscopist, specimen preparation, the expertise of the pathologist, and the recognition of the limitations of cytology. This article reviews the key cytologic features of important GI tract lesions, differential diagnoses, and pitfalls, and addresses the advantages and limitations of different collection techniques.