title: Prognosis of ovarian clear cell carcinoma compared to other histological subtypes: a meta-analysis.
abstract: OBJECTIVE
  To compare the survival outcome between clear cell carcinoma (CCC) and other histological subtypes in epithelial ovarian carcinoma (EOC).
  
  
  METHODS
  From January 1974 to February 2011, we identified a total of 31,800 (CCC; 2152, non-CCC; 29648) patients from 12 studies meeting the inclusion criteria.
  
  
  RESULTS
  Heterogeneity tests demonstrated significant between-study variation (I(2)=92.1%) with no significant difference in hazard ratio (HR) for death between CCC and non-CCC (HR; 1.16, 95% CI; 0.85-1.57, random-effects model). Comparing the HR based on stage I+II, and stage III+IV, between CCC and non-CCC, showed that CCC patients had a higher hazard rate for death than those with non-CCC of the ovary (stage I+II; HR; 1.17, 95% CI; 1.01-1.36, stage III+IV; HR; 1.65, 95% CI; 1.52-1.79). In a comparison of CCC and serous EOC, advanced stage (III and IV) CCC only showed a poorer hazard rate for death than serous EOC (HR; 1.71, 95% CI; 1.57-1.86).
  
  
  CONCLUSIONS
  This analysis suggests that ovarian CCC patients had poorer prognosis than those with other histological subtypes of EOC, especially in advanced EOC stages. Different treatment strategies may be needed for patients with ovarian CCC.
authors.affiliation: Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710, Republic of Korea.
authors.forename: Yoo-Young
authors.initials: YY
authors.lastname: Lee
authors.forename: Tae-Joong
authors.initials: TJ
authors.lastname: Kim
authors.forename: Min-Ji
authors.initials: MJ
authors.lastname: Kim
authors.forename: Ha-Jeong
authors.initials: HJ
authors.lastname: Kim
authors.forename: Taejong
authors.initials: T
authors.lastname: Song
authors.forename: Min Kyu
authors.initials: MK
authors.lastname: Kim
authors.forename: Chel Hun
authors.initials: CH
authors.lastname: Choi
authors.forename: Jeong-Won
authors.initials: JW
authors.lastname: Lee
authors.forename: Duk-Soo
authors.initials: DS
authors.lastname: Bae
authors.forename: Byoung-Gie
authors.initials: BG
authors.lastname: Kim
mesh_terms: D018262:Adenocarcinoma, Clear Cell / Q000473:pathology* / Q000628:therapy; D000077216:Carcinoma, Ovarian Epithelial; D005260:Female; D006801:Humans; D009367:Neoplasm Staging; D009375:Neoplasms, Glandular and Epithelial / Q000473:pathology* / Q000628:therapy; D010051:Ovarian Neoplasms / Q000473:pathology* / Q000628:therapy; D011379:Prognosis; D016016:Proportional Hazards Models; D015996:Survival Rate