A Seven Year Survey of Serous Tubal Intraepithelial Carcinoma in Surgical Specimens from BRCA+ and Routine Salpingo-Oophorectomies Using the SEE-FIM Protocol
James R Conner, Christopher P Crum, Colleen M Feltmate. Brigham and Women's Hospital, Boston, MA
Background: Serous tubal intraepithelial carcinoma (STIC) is considered an early phase of high-grade pelvic serous carcinoma (HGSC). Patients harboring mutations in the BRCA1 and BRCA2 genes (BRCA+) are at increased risk for HGSC and often opt for risk-reduction salpingo-oophorectomy (RRSO). Because STIC is clinically and radiographically undetectable, its true incidence in BRCA+ patients and in the general population is unknown. In 2005 we instituted the SEE-FIM protocol for analysis of BRCA+ tubes and a modified SEE-FIM protocol with exam of the entire fimbriae in all benign and malignant specimens for which an intact fallopian tube was received. The goal of this study was to arrive at a reasonable estimate of STIC in these two populations.
Design: 380 RRSOs performed on BRCA+ women along with approximately 2500 salpingo-oophorectomies (unilateral or bilateral) in women over age 50 performed for an indication other than BRCA+ or ovarian cancer were examined between 2005 and 2012. The latter encompassed only cases in which the entire fallopian fimbriae were received intact and included specimens received for benign conditions such as fibroids or pelvic pain, carcinomas of the endometrium or cervix. The records were reviewed to determine the number of STICs in each of the two populations.
Results: STICs were detected in 17 of 380 BRCA+ women for an incidence of 4.5%. The mean age was 56 (41-76). In women undergoing surgery for other indications, 6 cases of STIC and two of severe tubal atypia were discovered. Excluding the two atypias and three cases with early high-grade endometrial carcinoma, three of 2500 ((1:833 or .12%) fulfilled the criteria for an incidental STIC. Two were associted with low grade endometriod endometrial carcinomas and a third with a synchronous low grade mucinous tumor of the opposite ovary. The frequency of BRCA+ STIC was approximately 38 times that of incidental STICs.
Conclusions: In this study, BRCA+ women had a nearly 40 fold higher frequency of STIC relative to women undergoing surgery in whom a tubal carcinoma was not the indication. This analysis provides baseline data for estimating the likelihood of encountering a STIC in the general population and the frequency (1:833) approximates the prevalence of ovarian cancer in women over age 50. The rarity of this entity suggests a relatively brief period of clinical latency once carcinoma develops.
Category: Gynecologic & Obstetrics
Tuesday, March 5, 2013 1:00 PM
Proffered Papers: Section B, Tuesday Afternoon