Dualistic classification of epithelial ovarian cancer: surgical and survival outcomes in a large retrospective series.
BACKGROUND
Ovarian cancers have been recently categorized into types I and II according to a dualistic model of tumorigenesis. Data on the correlation between this classification and clinical outcome are still scarce and controversial.


METHODS
A retrospective analysis of patients with ovarian cancer treated from 1998 to 2013 and operated by the same surgeon was conducted. Patients were classified into two groups: type I (125 patients), including low-grade serous, mucinous, endometrioid, and clear cell tumors; and type II (286 patients), including high-grade serous tumors, unspecified adenocarcinomas, and undifferentiated carcinomas.


RESULTS
Type II patients had a significantly higher incidence of advanced disease than type I (88.4 vs. 65.6 %, P = 0.0001) and required more aggressive surgical procedures. Rates of optimal tumor debulking were almost similar between groups (92.6 vs. 91.7 %, type I vs. II, P = NS). After a median follow-up of 41 months, 207 patients (50.4 %) were alive and 204 (49.6 %) were dead; 79 type I patients (63.8 %) and 237 type II patients (82.7 %) experienced relapse (P = 0.02). Progression-free survival was significantly different between groups: 25 months for type I vs. 17 months for type II (P = 0.023). Overall survival was not significantly different between groups, with a median overall survival of 75 months for type I vs. 62 months for type II (P = 0.116).


CONCLUSIONS
The dualistic histotype-based classification into types I and II of ovarian cancer does not seem to correlate with prognosis. Different molecular characteristics of type I and II tumors may have therapeutic implications and should be deeply investigated.
Department of Gynecological and Obstetrical Sciences and Urological Sciences, Sapienza University of Rome, Rome, Italy.
Pierluigi Benedetti
PB
Panici
Claudia
C
Marchetti
Laura
L
Salerno
Angela
A
Musella
Laura
L
Vertechy
Innocenza
I
Palaia
Giorgia
G
Perniola
Ilary
I
Ruscito
Terenzio
T
Boni
Roberto
R
Angioli
Ludovico
L
Muzii
D018262:Adenocarcinoma, Clear Cell / Q000145:classification / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D002288:Adenocarcinoma, Mucinous / Q000145:classification / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018284:Cystadenocarcinoma, Serous / Q000145:classification / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D016889:Endometrial Neoplasms / Q000145:classification / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D010051:Ovarian Neoplasms / Q000145:classification / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate