Salpingo-oophorectomy and the risk of ovarian, fallopian tube, and peritoneal cancers in women with a BRCA1 or BRCA2 Mutation.
BACKGROUND
Women with BRCA1 or BRCA2 mutation are often advised to undergo preventive oophorectomy. The effectiveness of this intervention has not been prospectively evaluated in a large cohort.


OBJECTIVE
To estimate the incidence of ovarian, fallopian tube, and primary peritoneal cancer in women who carry a deleterious mutation in BRCA1 or BRCA2. To estimate the reduction in risk of these cancers associated with a bilateral prophylactic salpingo-oophorectomy.


METHODS
Women known to carry a BRCA1 or BRCA2 mutation were identified from an international registry between 1992 and 2003. A total of 1828 carriers at 1 of 32 centers in Canada, the United States, Europe, and Israel completed questionnaires at baseline and follow-up. Participants were observed from the date of study entry until: diagnosis of ovarian, fallopian tube, or peritoneal cancer; death; or the date of the most recent follow-up.


METHODS
Participants were divided into women who had undergone bilateral prophylactic oophorectomy and those who had not.


METHODS
The incidence of ovarian, peritoneal, and fallopian tube cancer was determined by survival analysis. The risk reduction associated with prophylactic salpingo-oophorectomy was evaluated by a time-dependent survival analysis, adjusting for covariates.


RESULTS
After a mean follow-up of 3.5 years, 50 incident ovarian, fallopian tube, and peritoneal cancer cases were reported in the cohort. Of the 1828 women, 555 (30%) underwent a bilateral prophylactic salpingo-oophorectomy prior to study entry, 490 (27%) underwent the procedure after entering the study, and 783 (43%) did not undergo the procedure. There were 32 incident cancers diagnosed in women with intact ovaries (1015/100,000 per year). Eleven cancer cases were identified at the time of prophylactic oophorectomy and 7 were diagnosed following prophylactic oophorectomy (217/100,000 per year). The estimated cumulative incidence of peritoneal cancer is 4.3% at 20 years after oophorectomy. The overall (adjusted) reduction in cancer risk associated with bilateral oophorectomy is 80% (multivariate hazard ratio = 0.20; 95% confidence interval, 0.07-0.58; P = .003).


CONCLUSIONS
Oophorectomy is associated with reduced risk of ovarian and fallopian tube cancer in high-risk women, although there is a substantial residual risk for peritoneal cancer in BRCA1 and BRCA2 mutation carriers following prophylactic salpingo-oophorectomy.
Finch
Amy
A
Centre for Research in Women's Health, Toronto-Sunnybrook Regional Cancer Center, Toronto, Ontario, Canada.
Beiner
Mario
M
Lubinski
Jan
J
Lynch
Henry T
HT
Moller
Pal
P
Rosen
Barry
B
Murphy
Joan
J
Ghadirian
Parviz
P
Friedman
Eitan
E
Foulkes
William D
WD
Kim-Sing
Charmaine
C
Wagner
Teresa
T
Tung
Nadine
N
Couch
Fergus
F
Stoppa-Lyonnet
Dominique
D
Ainsworth
Peter
P
Daly
Mary
M
Pasini
Babara
B
Gershoni-Baruch
Ruth
R
Eng
Charis
C
Olopade
Olufunmilayo I
OI
McLennan
Jane
J
Karlan
Beth
B
Weitzel
Jeffrey
J
Sun
Ping
P
Narod
Steven A
SA
D000328:Adult; D000368:Aged; D015331:Cohort Studies; D005185:Fallopian Tube Neoplasms / Q000453:epidemiology / Q000235:genetics / Q000517:prevention & control*; D005260:Female; D019398:Genes, BRCA1; D024522:Genes, BRCA2; D006801:Humans; D008875:Middle Aged; D009154:Mutation; D010051:Ovarian Neoplasms / Q000453:epidemiology / Q000235:genetics / Q000517:prevention & control*; D010052:Ovariectomy; D010534:Peritoneal Neoplasms / Q000453:epidemiology / Q000235:genetics / Q000517:prevention & control*; D012306:Risk; D016019:Survival Analysis