title: Dedifferentiated endometrioid carcinoma of the uterus : report of four cases and review of literature.
abstract: BACKGROUND
  Dedifferentiated endometrioid adenocarcinoma (DEAC) is rare and is known to be more aggressive than high-grade endometrioid carcinoma. Differentiating between the two is important to provide appropriate treatment for patients.
  
  
  METHODS
  This is a retrospective study including four cases of DEAC of the uterus, which was diagnosed and treated in our Obstetrics and Gynecology department between January 2013 and December 2015. Clinical, pathological, and immunohistochemical staining features are discussed. Each tumor was composed of undifferentiated carcinoma (UC) and low-grade endometrioid carcinoma with abrupt transition between them. Two patients showed recurrence or progression within one month postoperatively and died at the last follow-up. An immunohistochemical study showed PAX-8, ER, PR, and E-cadherin expression in UC component.
  
  
  CONCLUSIONS
  DEAC should not be underdiagnosed as conventional endometrioid adenocarcinoma due to its fulminant clinical course. Therefore, UC, including DEAC, should be further categorized to provide intensive treatment to improve patient survival.
authors.affiliation: Department of Hospital Pathology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 222, Banpo-daero, Seocho-gu, Seoul, 06591, Republic of Korea.
authors.forename: Jiheun
authors.initials: J
authors.lastname: Han
authors.affiliation: Department of Obstetrics and Gynecology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: Eun Young
authors.initials: EY
authors.lastname: Ki
authors.affiliation: Department of Radiology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: Sung Eun
authors.initials: SE
authors.lastname: Rha
authors.affiliation: Department of Obstetrics and Gynecology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
authors.forename: SooYoung
authors.initials: S
authors.lastname: Hur
authors.affiliation: Department of Hospital Pathology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 222, Banpo-daero, Seocho-gu, Seoul, 06591, Republic of Korea. klee@catholic.ac.kr.
authors.forename: Ahwon
authors.initials: A
authors.lastname: Lee
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism / Q000556:secondary* / Q000601:surgery; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D018269:Carcinoma, Endometrioid / Q000378:metabolism / Q000556:secondary* / Q000601:surgery; D054337:Cell Dedifferentiation; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008207:Lymphatic Metastasis; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D011379:Prognosis; D012189:Retrospective Studies; D014594:Uterine Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000601:surgery
chemical_list: D014408:Biomarkers, Tumor
keywords: Dedifferentiated endometrioid carcinoma; Endometrioid carcinoma; Undifferentiated carcinoma