Applications of Lectin Histochemistry and Cytochemistry in Diagnosis and Prognosis

The purpose of diagnostic histopathology and cytology is to categorize a disease process and predict how that disease will affect the patient. Pathologists are now combining careful morphological evaluation of the structure of the cell nucleus and cytoplasm with immunohistochemical and lectin histochemical studies to explore the molecular pathophysiology of diseased tissues and provide additional information to determine treatment and prognosis Many of the antibodies used in diagnostic tumor pathology recognize epitopes that include carbohydrate sequences, e.g., α-fetoprotein, carcinoembryonic antigen, CA125, which may also be identified by lectins Cancer-associated oligosaccharides are often oncodevelopmental in nature and reflect changes seen during normal development (1 ,2 ). Where as immunohistochemical studies often provide diagnostic information, previous reviews suggest that lectin histochemical data are rarely pathognomonic (3 ,4 ). This chapter will summarize more recent data, providing references to recent papers or review articles as an entry to the extensive literature. The lectins quoted, their abbreviations, and nominal specificities are shown in Table 1 .