Table 2.

NRGN expression (Cytoplasmic expression) in sinonasal papillomas

Grade	n	Negative (n, %)	Weak-Expression (n, %)	Medium-Expression (n, %)	Strong-Expression (n, %)
Normal mucosa	23	0 (0)	16 (69.57%)	7 (30.43%)	0 (0)
I	20	0 (0)	6 (30%)	13 (65%)	1 (5%)*
II	63	4 (6.35%)	19 (30.16%)	37 (58.73%)	3 (4.76%)**
III	19	1 (5.26%)	1 (5.26%)	11 (57.89%)	6 (31.58%)**#&
IV	13	1 (7.69%)	1 (7.69%)	7 (53.85%)	4 (30.77%)**##&

^**P < 0.01 compared with normal; #P < 0.05, ## P < 0.01 compared with Grade I; &P < 0.05 compared with Grade II