Analysis of K-ras codon 12 point mutations using duodenal lavage fluid fordiagnosis of pancreatic carcinoma

We evaluated the diagnostic significance of the K-ras point mutations at co don 12 in duodenal lavage fluid (DLF) compared with pure pancreatic juice ( PPJ). The DLF was easily and safely collected by injecting distilled water into the duodenum and then aspirating through the working channel of the en doscope during endoscopic retrograde cholangiopancreatography. Two types of DLF are collected this way: DLF 1 is collected just after insertion of the endoscope into the duodenum and DLF 2 is collected after cholangiopancreat ography and/or collection of the PPJ using secretin. Analysis of K-ras muta tions was performed using enriched polymerase chain reaction. In patients w ith pancreatic carcinoma (PC), K-ras mutations were detected in 14 of 23 (6 0.9%) in DLF 1, 16 of 21 (76.2%) in DLF 2, 14 of 20 (70.0%) in PPJ, and 19 of 21 (90.5%) in either DLF 1 or DLF 2. In patients with noncancerous pancr eatic diseases consisting of pancreatic cystic diseases and chronic pancrea titis, the incidence of K-ras mutations was 2 of 21 (9.5%) in DLF 1 and 7 o f 19 (36.8%) in DLF 2. These values were lower than that in PPJ, and there was significant difference between the incidence in DLF 1 and PPJ. These re sults suggested that DLF may provide a new and useful material for analysis of K-ras codon 12 point mutations in the diagnosis of PC.