Synchronous mucinous metaplasia and neoplasia of the female genital tract

Abstract

Objective: To describe the clinicopathological features of synchronous mucinous metaplasia and neoplasia of the female genital tract (SMMN-FGT). Methods: The sample consisted of 7 cases of SMMN-FGT recorded from November 2014 to September 2017 at Obstetrics and Gynecology Hospital, Fudan University.PAP method was used in immunohistochemistry.Clinical histories were retrieved and pathological slides were reviewed. Results: The patients were 37 to 70 years old(mean 54 years old). All patients showed endometrial mucinous lesions associated with cervical lesions. Three cases were an admixture of minimal deviation adenocarcinoma(MDA) and gastrictype adenocarcinoma(GAS). Three cases were an admixture of lobular endocervical glandular hyperplasia (LEGH), atypical LEGH and focal gastrictype adenocarcinoma in situ, one of which had early invasive gastrictype adenocarcinoma.Endometrium showed a structure of LEGH in one patient with focal simple gastric mucinous metaplasia in her cervix. Gastric mucinous differentiation was found in unilateral fallopian tube in 6 patients. Ovarian mucinous lesions were found in 3 patients. p16 was negative staining in 6 cases and positive in 1 case. CK7 was diffusely positive in all lesions. CK20 and CDX2 were negative or only focally positive.The expression of MUC6 was strongly positive staining or focal staining. p53 in GAS and GAS in situ had mutant expression, but wild expression in MDA region. Patients were followed up for 2 to 34 months and no recurrence was found. Conclusions: SMMN-FGT is a series of rare mucinous lesions involving multiple areas of the female genital tract, including benign or malignant lesions with gastric differentiation. It is not related to infection with high-risk human papilloma virus. When cervical gastrictype lesions are found, SMMN-FGT should be considered and should be differentiated from metastatic mucinous adenocarcinoma.