High-grade serous ovarian and fallopian tube carcinomas with similar clinicopathological characteristics might originate from serous tubal intraepithelial carcinoma in Chinese women

Aims: This study aimed to compare the clinicopathological features, incidence, and prognosis between type II ovarian carcinoma (OC) and fallopian tube carcinoma (FTC) in Chinese women and to analyze the origin of high-grade serous carcinoma (HGSC). Methods: Three hundreds and seventy-four OC cases and 45 FTC cases were retrospectively studied with histomorphology, tissue microarray, and immunohistochemistry. Results: Our data showed that the characteristics of OC and FTC in Chinese women were younger at diagnosis with worse prognosis. There was no significant difference between type II OC and FTC in the clinicopathological information and survival. Serous tubal intraepithelial carcinoma (STIC) were found in 41.7% (43/103) of ovarian high-grade serous carcinoma (HGSC) and 52.4% (22/42) cases of tubal HGSC, and 26 patients were found with only fallopian tube (FT) mucosal invasive carcinoma. Seventy-eight of 87 cases of ovarian HGSC with tubal lesions (STIC and/or FT mucosal invasive carcinoma) was in advanced stage. There was no significant difference between newly assigned FTC (ovarian HGSC with tubal lesions and FTC) and type II OC without tubal lesions in many clinicopathological parameters, expression of immunohistochemical indicators and survival, but type I OC was quite much different from the former two. Conclusions: Our data suggested that OC of type II and FTC might be originated from the same organ, and strongly supported the dualistic model of epithelial ovarian cancer. Moreover, this study provided a further clinical basis for the prophylactic salpingectomy to reduce the risk of OC.