Original ArticlesIncidental Serous Tubal Intraepithelial Carcinoma and Early Invasive Serous Carcinoma in the Nonprophylactic Setting Analysis of a Case SeriesMorrison, Jane C. MD*; Blanco, Luis Z. Jr MD*; Vang, Russell MD*,†; Ronnett, Brigitte M. MD*,†Author Information Departments of *Pathology †Gynecology and Obstetrics, The Johns Hopkins University School of Medicine, Baltimore, MD Present address: Jane Morrison, MD, OHSU, Department of Pathology, Mailcode L471, 3181 SW Sam Jackson Park Rd, Portland, OR 97239. Present address: Luis Z. Blanco, Jr, MD, Northwestern University Feinberg School of Medicine, 251 East Huron Street, Feinberg 7-335, Chicago, IL 60611. J.C.M. and L.Z.B. contributed equally. Conflicts of Interest and Source of Funding: The authors have disclosed that they have no significant relationships with, or financial interest in, any commercial companies pertaining to this article. Correspondence: Brigitte M. Ronnett, MD, Department of Pathology, The Johns Hopkins Hospital, Weinberg Building, Room 2242, 401 N. Broadway, Baltimore, MD 21231 (e-mail: [email protected]). The American Journal of Surgical Pathology: April 2015 - Volume 39 - Issue 4 - p 442-453 doi: 10.1097/PAS.0000000000000352 Buy Metrics Abstract A precursor for invasive ovarian/pelvic high-grade serous carcinoma, termed serous tubal intraepithelial carcinoma (STIC), has been identified and characterized through careful analysis of the fallopian tubes in both prophylactic salpingo-oophorectomy specimens obtained from women with either a family history of breast and/or ovarian cancer or germline mutations of BRCA1 and BRCA2 and in cases of pelvic high-grade serous carcinoma. Data on incidental STICs and clinically occult microscopic invasive high-grade serous carcinomas are limited. We analyzed the clinicopathologic features of 22 cases, including 15 pure STICs and 7 STICs associated with microscopic invasive high-grade serous carcinomas, identified incidentally in fallopian tubes removed for nonprophylactic indications. Patient age ranged from 39 to 79 years (mean: 62.7; median: 61), with only 1 patient under the age of 50. No patients were known to carry BRCA1 or BRCA2 mutations. Of the 12 pure STICs for which the location in the fallopian tube could be established, 9 were in the fimbriated portion, 1 was at the junction of the fimbria and infundibulum, and 2 were in the nonfimbriated tube. Of the 7 STICs with associated invasive high-grade serous carcinoma, 3 were located in the fimbriated portion, 2 were at the junction of the fimbria and infundibulum, and 2 were in the nonfimbriated tube. The invasive components were in the fallopian tube in 6 cases, 4 in subepithelial stroma of tubal mucosa, and 2 as an intramucosal (exophytic) luminal lesion without invasion of underlying subepithelial stroma (size range: 1 to 4 mm). The remaining case had a microscopic focus of high-grade serous carcinoma within the ipsilateral ovary (1.3 mm cortical focus) identified only on deeper sections, without an associated invasive component in the fallopian tube. The preferential finding of atypical epithelium with the cytologic features of high-grade serous carcinoma, namely STIC, in the fallopian tubes rather than the ovaries as an incidental (clinically occult) microscopic lesion in the absence of widespread pelvic carcinoma provides further evidence that STIC is the earliest form of pelvic high-grade serous carcinoma and that the fallopian tube is the site of origin. This study demonstrates the potential for complete examination of the fallopian tubes and ovaries to identify STICs and early invasive serous carcinomas that might be more amenable to the earliest intervention and potential cure. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.