Detection of Pancreatic Carcinoma (Diagnostic Value of K-ras Mutations in Circulating DNA from Serum)

Somatic activating mutations at codon 12 of theK-ras gene are present in the majority of exocrinepancreatic cancers and occur early in tumorgenesis. Theaim of this study was to test the feasibility of using a mutated K-ras gene from the serum as apotential tumor marker for detection of exocrinepancreatic carcinoma. Codon 12 K-ras mutations wereexamined in DNA extracted from the sera of 20 patients with pancreatic carcinomas, six patients withchronic pancreatitis, and five healthy individuals.K-ras gene mutations at codon 12 were detected in thesera of 14 of 20 patients with pancreatic carcinoma and in none of the six patients with chronicpancreatitis, or in the five healthy controls. Elevationof either CA19-9 or K-ras mutation was detected in 19/20patients. These results suggest that K-ras abnormalities in serum could be used as apotential tumor marker in patients with a pancreaticlesion. The absence of K-ras mutations in serum andpresence of CA19-9 in the normal range make thediagnosis of pancreatic cancer unlikely.