Although clear cell carcinoma of the ovary is considered to be a tumor with
poor prognosis, the clinical characteristics has not been defined. The aim
of this study was to evaluate the response of clear cell carcinoma of the
ovary to first and second-line chemotherapy and explore effective chemother
apy. Fifty-three patients with clear cell carcinoma of the ovary were enrol
led between 1988 and 1997 at our department. Since taxol was not available
in Japan at that time, cisplatin-based combination chemotherapy has been ex
clusively used as a standard first-line chemotherapy. Retrospective analyse
s of clinical characteristics and the response to first or second-line chem
otherapy were performed. Median age was 52 years (range 27-71 years). Tumor
s were 34% (18/53) stage I, 19% (5/53) stage II, 38% (20/53) stage III, and
19% (5/53) stage IV. All patients with I or II stage disease had optimal c
ytoreduction. Out of 25 patients with III or IV stage disease 20% (5/25) ha
d negative residual tumor, 36% (9/25) had <2 cm residual tumor, and 44% (11
/25) had greater than or equal to 2 cm residual tumor. All patients receive
d postoperative platinum-based chemotherapy. Of 23 patients with measurable
residual tumor 8.7% (2/23) completely and 13% (3/23) partially responded t
o first-line chemotherapy consisting of cisplatin, adriamycin and cyclo-pho
sphamide (CAP) or cisplatin and cyclophosphamide (CP) by CT scan or second
look laparotomy. Presence of endometriosis was 55% (29/53) but was not a pr
ognostic factor. Although overall response rate of ovarian clear cell carci
noma to first-line chemotherapy by CAP or CP was about 22%, EP or EJ consis
ting of etoposide and cisplatin or carboplatin used as a second-line chemot
herapy showed 29% response rate, while CPT-P consisting of CPT-11 and cispl
atin showed 40% response rate. Clear cell carcinomas were frequently presen
t at early stage, with association of endometriosis and with poor overall p
rognosis. Although patients with advanced ovarian clear cell carcinoma seem
ed to have better response to CPT-P than conventional platinum-based chemot
herapy, further studies are required with larger number of patients to draw
firm conclusions.