Early identification and diagnosis by type and stage is the key to high survival rates with thyroid cancer. To present the pathologist with current clinical information on diagnosis, differential diagnosis, staging, and prognosis of thyroid cancers, topics presented are: Poorly differentiated thyroid carcinoma; Paraganglimoa; Immunohistochemical markers for evaluation and prognosis in thyroid carcinoma; Familial endocrine syndromes; Parathyroid enoplasia; Inflammatory lesions of the thyroid associated with cancer; Assessing biological aggression in adrenal cortical neoplasia; Pituitary neoplasia; and Pancreatic endocrine neoplasia. Peter Sadow, whose clinical practice and research involve studying the mechanisms of endocrine carcinogenesis through translational studies involving the proteomics and genomics of endocrine neoplasms, primarily of the thyroid and adrenal glands, leads this issue.