[1060] Clinicopathologic Analysis of Tubal Intraepithelial Carcinoma (TIC) Associated with Pelvic (Non-Uterine) Gynecologic Carcinomas

CG Przybycin, BM Ronnett, RJ Kurman, RS Vang. Johns Hopkins Hospital, Baltimore, MD

Background: TIC, which has been reported in association with 48% of pelvic serous carcinomas (Kindelberger, Am J Surg Pathol 2007), has been implicated as evidence of fallopian tube (FT) origin for carcinomas that would have been otherwise classified as primary ovarian or peritoneal. The current study addresses the frequency of identification of TIC, and thus potential FT origin, of pelvic (non-uterine) gynecologic carcinomas at our institution.
Design: A series of 94 consecutive cases of pelvic (non-uterine) carcinomas encountered from 1/2006-7/2008 was evaluated to identify those for which all resected FT tissue was submitted for histologic examination. The presence of TIC and its location and relationship to invasive carcinoma in the FTs and ovaries was assessed.
Results: Among 42 cases with complete microscopic examination of all FT tissue, carcinoma subtypes included 37 high-grade serous, 2 endometrioid, 1 clear cell, 1 poorly differentiated carcinoma, and 1 malignant mesodermal mixed tumor. TIC was identified in 12 cases (32%) of high-grade serous carcinoma but not among any of the other subtypes. Among these, all would have been classified as ovarian or peritoneal in origin per conventional criteria based on disease distribution (sufficient ovarian tumor or extensive peritoneal tumor). TIC was located in the fimbriated end in 11 cases. Both TIC and adjacent invasive carcinoma were present in the FT in 11 cases (10 unilateral, 1 bilateral); 1 case had only TIC without invasive carcinoma in the FT. The 11 unilateral TICs were associated with bilateral ovarian involvement by carcinoma in 9 and unilateral ovarian involvement in 2 (contralateral ovary absent in both). In 6 cases there was more than one focus of TIC in the same FT.
Conclusions: Despite the expected bias towards serous carcinoma in this series of pelvic carcinomas, TIC was not identified in association with other subtypes of carcinoma. This study, in conjunction with the one cited above, suggests that one-third to one-half of pelvic serous carcinomas are potentially of FT origin. Molecular studies are required to establish that TIC is the precursor lesion rather than intraepithelial spread from adjacent carcinoma of ovarian or peritoneal origin.
Category: Gynecologic

Tuesday, March 10, 2009 1:00 PM

Poster Session IV # 174, Tuesday Afternoon