Background: Endometriosis associated ovarian carcinoma (EAOC) is rare. An important similarity between endometriosis and ovarian cancer is seeding of the cells to peritoneum by fimbrial end of the fallopian tube. Only difference between two diseases are CD10 and calretinin expression patterns. Calretinin and CD10 expression patterns of normal ovary and endometriosis were researched in this study. Material and Methods: A total of 259 endometriosis cases were evaluated between January 1, 2010 to March 1, 2016 at the Department of Surgical Pathology of Osmangazi University School of Medicine. According to files, 169 non-neoplastic cases, 66 malign tumors, and 24 benign neoplasm were associated endometriosis. CDIO immunohistochemistry was applied to 82 sections, calretinin immunohistochemistry was applied to 53 out of 169 non-neoplastic group, six out of 24 benign tumor group, and 24 out of 66 malign tumor group. Results: There were 48 fallopian tube endometriosis cases in non-neoplastic group, 22 tubal endometriosis cases in malign tumor group, and six tubal endometriosis cases in benign tumor group. Focal segmental calretinin expression "calretinin signature" in tubal epithelium was detected 11.3% (6/53) of non-neoplastic tubal endometriosis cases and three in six of the cases in benign tumor group. Focal calretinin expression in tubal and/or tumoral epithelium was observed 41.6% (10/24) of the cases with EAOC group. Conclusion: After applying sectioning and extensively examining the fimbriated end (SEE-FIM) protocol, detection of occult or usual type endometriosis in tuba increased. This study showed that calretinin signature in the fimbrial end of tuba is not a reactive lesion.