Expression of the insulin-like growth factor-II mRNA-binding protein 3 (IMP3) and carcinoembryonic antigen (CEA) in mucinous minimal deviation adenocarcinoma.

Mucinous minimal deviation adenocarcinoma (MDA) is a rare highly differentiated mucinous adenocarcinoma of the uterine cervix, which always remains a diagnostic dilemma. Lobular endocervical glandular hyperplasia (LEGH), a rare benign lesion of the uterine cervix, is identified as precursor of mucinous MDA. The insulin-like growth factor-II mRNA-binding protein 3 (IMP3) is expressed in a number of cancers and is associated with progression of the tumors. The purpose of this study was to evaluate the expression of the IMP3, carcinoembryonic antigen (CEA), and cyclin-dependent kinase inhibitor p16(INK4a) in mucinous MDA and LEGH, and to estimate the possible role of these biomarkers in the diagnosis of mucinous MDA. Twelve samples of MDA, eight samples of lobular endocervical glandular hyperplasia (LEGH), and 20 normal control cases were included in this study. Typical lesions and less well-differentiated lesions coexisted in 11/12 mucinous MDA samples. Positive cytoplasmic expression for IMP3 and CEA was found in less well-differentiated lesions of all 11 mucinous MDA samples, primarily with strong to intermediate staining intensity. The typical well-differentiated lesions of all 12 MDA cases and 8 cases of LEGH showed negativity for both IMP3 and CEA. No exact p16(INK4a) positivity was observed in 12 mucinous MDA and 8 LEGH. The significant expression of IMP3 and CEA in less well-differentiated foci of mucinous MDA may be helpful in the diagnosis of mucinous MDA to some extent, particularly in small specimens from cervical biopsy. More cases and in-depth researches are needed to elucidate the potential different mechanisms between typical and less well-differentiated lesions of mucinous MDA.