Methylation changes at the GNAS imprinted locus in pancreatic cystic neoplasms are important for the diagnosis of malignant cysts

Table 2 Frequency of GNAS locus methylation changes in malignant, mucinous, and benign cysts, n (%)

Informative cyst fluid methylation analysis, 38 samples	Malignant, n = 8	Mucinous pre-malignant, n = 10	Benign, n = 20	P value
NESP55 hypermethylation	3 (37.5)	0 (0.0 )	1 (5.0)	0.053
GNASAS hypermethylation	3 (37.5)	1 (10.0)	3 (15.0)	0.065
GNASXL hypermethylation	4 (50)	0 (0.0)	2 (10.0)	0.004
GNAS1A hypermethylation	1 (12.5)	0 (0.0)	0 (0)	0.0355
GNAS locus methylation changes	6 (75.0)	0 (0.0)	2 (6.7)	0.000

GNAS locus methylation changes: DMR hypermethylation or GNAS intragenic hypomethylation. GNAS: Guanine nucleotide-binding protein, alpha stimulating.