title: Classification of follicular cell tumors of the thyroid gland: analysis involving Japanese patients from one institute.
abstract: Prognostic analyses of thyroid carcinomas of follicular cell origin were carried out on patients treated at Kuma Hospital, Kobe, Japan. A new histopathological classification based on the prognostic evidence is proposed in this study, and it is applicable to the patients treated curatively. Major histological types of papillary carcinoma, follicular carcinoma and poorly differentiated carcinoma were combined into one single entity of follicular cell adenocarcinoma because (i) they have the same cell origin (follicular cell); (ii) clear-cut separation of papillary and follicular carcinoma is not always possible, and 10 year cause-specific survival was essentially similar when the patients were treated curatively; and (iii) poorly differentiated carcinoma usually has a background of either papillary or follicular carcinoma. This adenocarcinoma together with undifferentiated carcinoma was stratified into four prognostic groups using pure morphological criteria of the degree of cellular differentiation and histological grade. They are termed well-differentiated adenocarcinoma, moderately differentiated adenocarcinoma, poorly differentiated carcinoma and undifferentiated carcinoma of the thyroid. The 10 year disease-free survival rates were 86.3-93.1%, 65.4-78.7%, and 43.0-53.8%, and 0%, respectively. The 10 year cause-specific survival rates were 97.2-100%, 91.5-97.4%, and 71.2-80.0%, and 0%, respectively.
authors.affiliation: Department of Human Pathology, Wakayama Medical University, Wakayama, Japan. kakudo-k@wakayamamed.ac.jp
authors.forename: Kennichi
authors.initials: K
authors.lastname: Kakudo
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Bai
authors.forename: Shoichi
authors.initials: S
authors.lastname: Katayama
authors.forename: Mitsuyoshi
authors.initials: M
authors.lastname: Hirokawa
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Ito
authors.forename: Akira
authors.initials: A
authors.lastname: Miyauchi
authors.forename: Kanji
authors.initials: K
authors.lastname: Kuma
mesh_terms: D018263:Adenocarcinoma, Follicular / Q000145:classification* / Q000401:mortality / Q000473:pathology; D044466:Asian People; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D013964:Thyroid Neoplasms / Q000145:classification* / Q000401:mortality / Q000473:pathology