Expressions of mucin 1 and 2 in lesions of extramammary Paget's disease

Objective To study the expressions of mucin (MUC) 1 and 2 in extramammary Paget's disease(EMPD) lesions. Methods Tissue specimens were obtained from the lesions of 19 patients with EMPD and normal skin of 19 human controls during cosmetic surgery. Streptavidin-perosidase (SP) technique was used to detect the expressions of MUC1 and MUC2 in these specimens. Results As haematoxylin-eosin (HE) staining showed, 3 cases were accompanied by poorly differentiated adenocarcinoma, 6 were invasive Paget's disease and 10 were intraepithelial EMPD. MUC1 was expressed in 2 cases accompanied by poorly differentiated adenocarcinoma, and in all the cases of invasive and intraepithelial EMPD; MUC2 was observed in all the cases of adenocarcinoma-complicated EMPD and invasive EMPD, but only in 2 of 10 cases of intraepithelial EMPD.Neither MUC1 nor MUC2 was observed in normal control specimens. A significant increase was observed in the expression of MUC1 in lesions of intraepithelial EMPD compared with invasive EMPD and adenocarcinoma-complicated EMPD (both P ＜ 0.05), and in the expression of MUC2 in lesions of invasive EMPD and adenocarcinoma-complicated EMPD compared with intraepithelial EMPD (both P ＜ 0.05). The expression of MUC1 was uncorrelated to that of MUC2 (r= -0.5, P＞ 0.05). Conclusions MUC1 is generally expressed in the lesions of EMPD, while MUC2 is expressed in those of adenocarcinoma-complicated EMPD and invasive EMPD. Key words: Paget's disease, extramammary;  Mucins;  Gene expression