This course will focus on patterns of presentation of several types of thyroid lesions in both cytologic and histologic preparations. Patterns to be discussed and demonstrated include: papillary, follicular, Hurthle cell/oncocytic, lymphoid and spindle/small cell. The spectrum of benign and malignant lesions in these pattern categories will be discussed including diagnostic clues, differential diagnosis and the role of special studies. A limited number of loan sets of glass slides, illustrating these five patterns will be available for advance mailing. All registrants will receive a set of transparencies after the meeting. A syllabus will be distributed at the course.