title: Clinical experience in ovarian squamous cell carcinoma arising from mature cystic teratoma: A rare entity.
abstract: OBJECTIVE
  We sought to investigate the clinicopathologic features of ovarian squamous cell carcinomas arising from mature cystic teratomas (MCT) and to report our clinical experience and lessons learned.
  
  
  METHODS
  From January 1993 to November 2012, a total of 6,260 women with ovarian MCT were surgically treated at Cheil General Hospital and Women's Healthcare Center. Among them, the cases with malignant transformation to squamous cell carcinoma were included in this analysis. Patient demographic characteristics, surgical findings, and prognosis were evaluated retrospectively.
  
  
  RESULTS
  Of the 6,260 ovarian MCT patients, four (0.06%) had ovarian squamous cell carcinoma arising from MCT. The mean patient age was 43 years (range, 35-51 years), and the mean tumor size was 12 cm (range, 9-16 cm), with two patients in the International Federation of Gynecology and Obstetrics stage I and the other two in stage III. Upon preoperative imaging, all cases were expected to be benign ovarian tumors, but the preoperative squamous cell carcinoma antigen level was elevated from 1.5 ng/mL in stage Ia to 11.3 ng/mL in stage IIIc, suggesting malignancy, while the CA-125 level was normal in two of the three patients who received the test. Optimal debulking surgery was performed and adjuvant chemotherapy was used in all patients, but death from the recurrence of disease occurred in one patient, whose overall survival was 10 months.
  
  
  CONCLUSIONS
  Ovarian squamous cell carcinoma arising from MCT is extremely rare, and it is rarely diagnosed preoperatively on imaging workups. Measuring the squamous cell carcinoma antigen level might be a useful diagnostic clue, and it might also be predictive of the tumor stage. An adequate staging surgery should be included in the standard treatment, but multicenter studies are needed to confirm this.
authors.affiliation: Department of Obstetrics and Gynecology, Cheil General Hospital and Women's Healthcare Center, Kwandong University College of Medicine, Seoul, Korea.
authors.forename: Eun-Jeong
authors.initials: EJ
authors.lastname: Choi
authors.affiliation: Department of Obstetrics and Gynecology, Cheil General Hospital and Women's Healthcare Center, Kwandong University College of Medicine, Seoul, Korea.
authors.forename: Yu-Jin
authors.initials: YJ
authors.lastname: Koo
authors.affiliation: Department of Obstetrics and Gynecology, Cheil General Hospital and Women's Healthcare Center, Kwandong University College of Medicine, Seoul, Korea.
authors.forename: Ji-Hyun
authors.initials: JH
authors.lastname: Jeon
authors.affiliation: Department of Obstetrics and Gynecology, Cheil General Hospital and Women's Healthcare Center, Kwandong University College of Medicine, Seoul, Korea.
authors.forename: Tae-Jin
authors.initials: TJ
authors.lastname: Kim
authors.affiliation: Department of Obstetrics and Gynecology, Cheil General Hospital and Women's Healthcare Center, Kwandong University College of Medicine, Seoul, Korea.
authors.forename: Ki-Heon
authors.initials: KH
authors.lastname: Lee
authors.affiliation: Department of Obstetrics and Gynecology, Cheil General Hospital and Women's Healthcare Center, Kwandong University College of Medicine, Seoul, Korea.
authors.forename: Kyung-Taek
authors.initials: KT
authors.lastname: Lim
keywords: Malignant transformation; Mature cystic teratoma; Ovary; Squamous cell carcinoma
references.citation: Cancer. 1986 May 1;57(9):1725-30
references.pmid: 3513943
references.citation: Gynecol Oncol. 1996 Dec;63(3):364-70
references.pmid: 8946873
references.citation: Am J Obstet Gynecol. 1997 Jul;177(1):109-14
references.pmid: 9240592
references.citation: Obstet Gynecol. 1994 Jul;84(1):22-8
references.pmid: 8008317
references.citation: Eur J Obstet Gynecol Reprod Biol. 2000 Feb;88(2):153-7
references.pmid: 10690674
references.citation: Singapore Med J. 1988 Feb;29(1):30-4
references.pmid: 2841767
references.citation: Obstet Gynecol. 1997 Jun;89(6):1017-22
references.pmid: 9170484
references.citation: Taiwan J Obstet Gynecol. 2012 Sep;51(3):446-8
references.pmid: 23040935
references.citation: Arch Gynecol Obstet. 2008 Sep;278(3):287-90
references.pmid: 18239927
references.citation: Lancet Oncol. 2008 Dec;9(12):1173-80
references.pmid: 19038764
references.citation: Clin Imaging. 2011 Jul-Aug;35(4):294-300
references.pmid: 21724123
references.citation: Cancer. 1998 Jun 1;82(11):2249-55
references.pmid: 9610706
references.citation: Br J Cancer. 1988 Jul;58(1):93-8
references.pmid: 3166898