[Hereditary pancreatitis - a clinically relevant cause of pancreatic adenocarcinoma?]

Hereditary pancreatitis is an autosomal dominant disease. Recently, the genetic defect has been mapped to chromosome 7q35 and consists mainly of a point mutation in exon 3 of the cationic trypsinogen gene which causes an Arg(CGC)-His(CAC) substitution at residue 117. In patients with hereditary pancreatitis the estimated cumulative risk for pancreatic carcinoma to age 70 approaches 40 %. Thus, the role of hereditary pancreatitis in the pathogenesis of pancreatic carcinoma is of interest.

DNA was extracted from peripheral blood (n = 16), fresh tumor tissue (n = 29) and formalin fixed and paraffin embedded tumor tissue (n = 5) of 50 patients with ductal adenocarcinoma of the pancreas. We specifically amplified exon 3 and the intronic flanking sequences of the cationic trypsinogen gene by nested PCR and performed restriction fragment length polymorphism analysis using the restriction enzyme Afl III. In patients with hereditary pancreatitis the G : A point mutation creates a recognition site for Afl III which is not present in unaffected individuals.

None of the 50 patients with ductal adenocarcinoma of the pancreas revealed the G : A point mutation in exon 3 of the cationic trypsinogen gene which is characteristic of hereditary pancreatitis. In addition sequencing of exon 3 did not reveal any other mutations in the DNA of patients with pancreatic adenocarcinoma.

Although hereditary pancreatitis markedly increases the risk for pancreatic cancer, it is rare and probably of little significance with respect to the pathogenesis of the majority of pancreatic adenocarcinomas.