BACKGROUND: Patients with in situ extramammary Paget's disease (EMPD) tend to have a good prognosis, although dermal invasion and metastasis are associated with significantly increased morbidity and mortality. Previous studies have addressed mechanisms underlying the EMPD pathogenesis; however, no molecular markers that reflect invasiveness or progression have been established. OBJECTIVE: This study aims to identify a reliable marker for predicting the risk of invasion and metastasis in EMPD. METHODS: We performed an initial microarray screening for in situ, invasive or metastatic lymph node lesions of EMPD. We analysed 44 specimens from 38 primary EMPD cases by immunohistochemical staining. RESULTS: We found that expressions of MUC5AC directly correlate with invasion and prognosis. Labelling rates of tumour cells were scored by staining intensity on a four-tiered scale (- to 3+) to investigate the correlation between the expression score of these molecular markers and the type of EMPD lesion. All the specimens scored positive (3+) for MUC1 and negative (-) for MUC6. MUC5AC expression was detected in 19 of 44 (43.2%) specimens. Invasive lesions and metastatic lymph nodes tended to express MUC5AC significantly higher than in situ lesions (P < 0.01). MUC2 was positive in 10 specimens (22.7%). There was no significant difference between the degree of MUC2 expression and invasiveness. CONCLUSION: The degree of MUC5AC expression may correlate with the invasiveness and progression of EMPD, and may be a useful marker for identifying high-risk EMPD cases.
BACKGROUND:Patients with in situ extramammary Paget's disease (EMPD) tend to have a good prognosis, although dermal invasion and metastasis are associated with significantly increased morbidity and mortality. Previous studies have addressed mechanisms underlying the EMPD pathogenesis; however, no molecular markers that reflect invasiveness or progression have been established. OBJECTIVE: This study aims to identify a reliable marker for predicting the risk of invasion and metastasis in EMPD. METHODS: We performed an initial microarray screening for in situ, invasive or metastatic lymph node lesions of EMPD. We analysed 44 specimens from 38 primary EMPD cases by immunohistochemical staining. RESULTS: We found that expressions of MUC5AC directly correlate with invasion and prognosis. Labelling rates of tumour cells were scored by staining intensity on a four-tiered scale (- to 3+) to investigate the correlation between the expression score of these molecular markers and the type of EMPD lesion. All the specimens scored positive (3+) for MUC1 and negative (-) for MUC6. MUC5AC expression was detected in 19 of 44 (43.2%) specimens. Invasive lesions and metastatic lymph nodes tended to express MUC5AC significantly higher than in situ lesions (P < 0.01). MUC2 was positive in 10 specimens (22.7%). There was no significant difference between the degree of MUC2 expression and invasiveness. CONCLUSION: The degree of MUC5AC expression may correlate with the invasiveness and progression of EMPD, and may be a useful marker for identifying high-risk EMPD cases.
Authors: I Lakshmanan; S Rachagani; R Hauke; S R Krishn; S Paknikar; P Seshacharyulu; S Karmakar; R K Nimmakayala; G Kaushik; S L Johansson; G B Carey; M P Ponnusamy; S Kaur; S K Batra; A K Ganti Journal: Oncogene Date: 2016-01-11 Impact factor: 9.867