Ji-Youn Sung1, Yoon Yang Jung2, Hyun-Soo Kim3. 1. Department of Pathology, Kyung Hee University School of Medicine, Seoul, Republic of Korea. 2. Department of Pathology, Myongji Hospital, Goyang, Republic of Korea. 3. Department of Pathology, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea hyunsookim@yuhs.ac.
Abstract
BACKGROUND/AIM: Mucinous metaplasia of the endometrium occurs as a spectrum of epithelial alterations ranging from the formation of simple, tubular glands to architecturally complex glandular proliferation with intraglandular papillary projection and cellular tufts. Endometrial mucinous metaplasia often presents a diagnostic challenge in endometrial curettage. MATERIALS AND METHODS: We analyzed the clinicopathological characteristics and the mutation status for V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) of 11 cases of endometrial mucinous metaplasia. Electronic medical record review and histopathological examination were performed. KRAS mutation status was analyzed using a pyrosequencing technique. RESULTS: Cases were classified histopathologically into simple (5/11) or papillary (6/11) mucinous metaplasias. All (6/6) papillary mucinous metaplasias were associated with atypical hyperplasia/endometrioid intraepithelial neoplasia (AH/EIN; 1/6) or carcinoma (5/6), whereas in a single patient with simple mucinous metaplasia, grade 1 endometrioid carcinoma was incidentally detected. The difference in frequency of association of the metaplasia with AH/EIN or carcinoma was significant (p=0.015). KRAS mutations were identified in five out of six cases of papillary mucinous metaplasias, comprising three cases with G12D and two with G12V mutations; the frequency of KRAS mutation was significantly higher (p=0.015) than in cases of simple mucinous metaplasia (0/5). CONCLUSION: Papillary mucinous metaplasia is frequently associated with endometrial neoplastic lesions. The high incidence of KRAS mutations in papillary mucinous metaplasia suggests that papillary mucinous metaplasia may be a precancerous lesion of a certain subset of mucinous carcinomas of the endometrium. Copyright
BACKGROUND/AIM: Mucinous metaplasia of the endometrium occurs as a spectrum of epithelial alterations ranging from the formation of simple, tubular glands to architecturally complex glandular proliferation with intraglandular papillary projection and cellular tufts. Endometrial mucinous metaplasia often presents a diagnostic challenge in endometrial curettage. MATERIALS AND METHODS: We analyzed the clinicopathological characteristics and the mutation status for V-Ki-ras2 Kirsten ratsarcoma viral oncogene homolog (KRAS) of 11 cases of endometrial mucinous metaplasia. Electronic medical record review and histopathological examination were performed. KRAS mutation status was analyzed using a pyrosequencing technique. RESULTS: Cases were classified histopathologically into simple (5/11) or papillary (6/11) mucinous metaplasias. All (6/6) papillary mucinous metaplasias were associated with atypical hyperplasia/endometrioid intraepithelial neoplasia (AH/EIN; 1/6) or carcinoma (5/6), whereas in a single patient with simple mucinous metaplasia, grade 1 endometrioid carcinoma was incidentally detected. The difference in frequency of association of the metaplasia with AH/EIN or carcinoma was significant (p=0.015). KRAS mutations were identified in five out of six cases of papillary mucinous metaplasias, comprising three cases with G12D and two with G12V mutations; the frequency of KRAS mutation was significantly higher (p=0.015) than in cases of simple mucinous metaplasia (0/5). CONCLUSION:Papillary mucinous metaplasia is frequently associated with endometrial neoplastic lesions. The high incidence of KRAS mutations in papillary mucinous metaplasia suggests that papillary mucinous metaplasia may be a precancerous lesion of a certain subset of mucinous carcinomas of the endometrium. Copyright