Table 3.

Somatic alterations in periampullary adenocarcinoma.

Gene	Type of Alterations	Frequency	Function
KRAS	Mutation	30-60%	GTPase
BRAF	Mutation	0-66%	Growth signal transduction protein kinase
PIK3CA	Mutation	5.3%	Signal transduction
MET	Mutation	4.25%	Receptor tyrosine kinase
EGFR/HER1/ERBB1	Mutation	1%	Cell surface receptors
NRAS	Mutation	1%	GTPase