Expression of endothelial cell specific molecule-1 and its clinical significance in pituitary null cell adenomas

Abstract

Objective To explore the expression of endothelial cell specific molecule-1(ESM-1)and its clinical significance in pituitary null cell adenoma(NCA). Methods Forty-six cases of NCA specimens, collected from resection of pituitary tumor via microscopic transsphenoidal approach in our hospital from January 2010 to May 2014, were chosen in our study; ESM-1 expressions in the NCA specimens was detected by immunohistochemical S-P method, and the relations of expression results with gender(male: 29; female:17), age(18-45 years old: 16; ≥46 years old: 30), maximum tumor diameter(1-3 cm: 34; ≥3 cm: 11; <1 cm: 1), invasion state(invasive NCA: 30; non-invasive NCA: 16), Ki-67 labeling index(<3%: 29; ≥3%: 17)and pathological features were analyzed. Results ESM-1 expression was observed in endothelial cells and adenoma cells, with positive rates 100% and 86.96%(40/46); in the endothelial cells, high expression was noted in 32 patients; and in the adenoma cells, high expression was noted in 25 patients; no significant difference of high expression was noted between the two(P>0.05). As compared with that of noninvasive NCA(7/16), the high expression of ESM-1 of invasive NCA(23/30)in endothelial cells was significantly increased(P 0.05). In endothelial cells, high expression of ESM-1 was not significantly different in patients of different ages, gender, maximum tumor diameters or Ki-67 labeling indexes(P>0.05); in adenoma cells, high expression of ESM-1 was not significantly different in patients of different ages, gender, maximum tumor diameters, Ki-67 labeling indexes or invasion states(P>0.05). Conclusion ESM-l in endothelial cells could be used as a marker of aggressive behavior in NCA. Key words: Pituitary adenoma; Null cell adenoma; Endothelial cell specific molecule-1; Invasiveness