title: Prognostic classification of thyroid follicular cell tumors using Ki-67 labeling index: risk stratification of thyroid follicular cell carcinomas.
abstract: This review emphasizes that the so-called high-risk thyroid carcinoma is not a distinct tumor entity, but a group of tumors with different histologies. High-grade histological features, such as tumor necrosis, increased mitoses, and nuclear pleomorphism, together with high Ki-67 labeling index (more than 10%), are good indicators of high-risk thyroid carcinoma and suggest a possible risk for anaplastic transformation. This review proposes the stratification of patients with thyroid carcinoma into low-, moderate-, and high-risk groups based on Ki-67 labeling index, which should be useful for the clinical management of patients, even after initial surgery. Currently, both the aggressive variant of papillary carcinoma and poorly differentiated carcinoma are aggressively treated by a completion of total thyroidectomy with prophylactic lymph node dissection followed by radioactive iodine treatment. Therefore, patients with moderate-risk or high-risk thyroid carcinoma based on Ki-67 labeling index should also be considered candidates for this treatment strategy.
authors.affiliation: Department of Pathology and Laboratory Medicine, Nara Hospital Kinki University Faculty of Medicine, Ikoma-city 630-0293, Japan.
authors.forename: Kennichi
authors.initials: K
authors.lastname: Kakudo
authors.forename: Tomoko
authors.initials: T
authors.lastname: Wakasa
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Ohta
authors.forename: Katsunari
authors.initials: K
authors.lastname: Yane
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Ito
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Yamashita
mesh_terms: D018263:Adenocarcinoma, Follicular / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology / Q000628:therapy; D003131:Combined Modality Therapy; D019317:Evidence-Based Medicine; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism*; D009363:Neoplasm Proteins / Q000378:metabolism*; D011379:Prognosis; D018570:Risk Assessment; D013961:Thyroid Gland / Q000378:metabolism* / Q000473:pathology / Q000528:radiation effects / Q000601:surgery; D013964:Thyroid Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology / Q000628:therapy
chemical_list: D019394:Ki-67 Antigen; D009363:Neoplasm Proteins