Serum Nectin-4 as a Potential Prognostic Biomarker for Extramammary Paget Disease

Nectin cell adhesion molecule 4 (Nectin-4) is overexpressed in the tissue of extramammary Paget disease (EMPD), and its potential role as a circulating biomarker remains poorly explored. We therefore investigated serum levels of Nectin-4 in EMPD patients and healthy controls by ELISA assay and analysed its clinical relevance. Serum Nectin-4 levels were significantly higher in patients than in controls (p = 0.0015), especially in advanced stages (IIIB-IV; p = 0.028). Serum Nectin-4 levels tended to decrease following effective treatment and increase upon disease progression. Serum Nectin-4 correlated strongly with CEA (r = 0.705) but not with CYFRA. Patients with high serum Nectin-4 levels (cut-off of 394.2 pg/mL) exhibited shorter overall survival (p = 0.012). Further research is needed to elucidate the role of Nectin-4 in EMPD; however, these findings suggest that serum Nectin-4 may serve as a single marker for prognosis and treatment monitoring in EMPD.