The results of the present study indicated that in pituitary NCA, even ESM-1 expression was observed in both vascular endothelial and adenoma tissues, a significant positive association between tumor invasion and ESM-1 expression was observed only in vascular endothelial tissues, suggesting that the progression of tumor occurs mainly through the vascular structure via ESM-1-mediated mechanism is involved. Here, ESM1 is linked to adenoma.