Less impact of adjuvant chemotherapy for stage I clear cell carcinoma of the ovary: a retrospective Japan Clear Cell Carcinoma Study.
BACKGROUND
Ovarian clear cell carcinoma (CCC) is regarded as grade 3 tumor, and the National Comprehensive Cancer Network (NCCN) Clinical Practice Guidelines recommend adjuvant chemotherapy for the tumor even at stage IA. However, CCC often showed chemo-resistant phenotype, and the effect of adjuvant chemotherapy still remained uncertain.


METHODS
Clear cell carcinoma cases treated at collaborating institutions during the period 1992-2005 were retrospectively identified. After a central pathological review, survival analysis was estimated by the Kaplan-Meier method, and prognostic factors were evaluated using a Cox regression model.


RESULTS
Among 219 patients with stage I CCC, 195 patients received adjuvant chemotherapy (C+) and 24 patients (C-) did not. The C+ group had 77 pT1a and 118 pT1c cases, and the C- group included 18 pT1a and 6 pT1c tumors (P < 0.001). The median age was 52 years in the C+ group and 57 years in C- group (P = 0.04). During the median follow-up period of 48 months (range, 7-160 years), relapse was observed in one patient (4%) in the C- group and in 35 patients (18%) in the C+ group. There were no statistical differences of progression-free survival and overall survival between the C+ and the C- groups. Multivariate analysis revealed that peritoneal cytology status (P = 0.02) and pT status (P = 0.04) were independent prognostic factors for progression-free survival; however, adjuvant chemotherapy was not a prognostic factor (P = 0.80).


CONCLUSIONS
Although the present study was a limited retrospective investigation, it suggested that adjuvant chemotherapy had little impact on the survival of stage I CCC patients. Further strategy, such as a molecular targeting agent, is needed to improve survival of CCC, especially in cases with positive peritoneal washing.
Department of Obstetrics and Gynecology, National Defense Medical College, Tokorozawa, Saitama, Japan. mastkn@ndmc.ac.jp
Masashi
M
Takano
Toru
T
Sugiyama
Nobuo
N
Yaegashi
Satoru
S
Sagae
Kazuo
K
Kuzuya
Yasuhiro
Y
Udagawa
Hiroshi
H
Tsuda
Mitsuaki
M
Suzuki
Junzo
J
Kigawa
Tomoko
T
Goto
Hitoshi
H
Tsuda
Takuya
T
Moriya
Yoshihiro
Y
Kikuchi
D018262:Adenocarcinoma, Clear Cell / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D017024:Chemotherapy, Adjuvant / Q000706:statistics & numerical data; D002945:Cisplatin / Q000008:administration & dosage; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007564:Japan; D008875:Middle Aged; D009367:Neoplasm Staging; D010051:Ovarian Neoplasms / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D010053:Ovary / Q000187:drug effects* / Q000473:pathology; D017239:Paclitaxel / Q000008:administration & dosage; D011379:Prognosis; D012189:Retrospective Studies; D016019:Survival Analysis; D017211:Treatment Failure
D017239:Paclitaxel; D002945:Cisplatin