Basic Research
Copyright ©2006 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. May 21, 2006; 12(19): 3038-3043
Published online May 21, 2006. doi: 10.3748/wjg.v12.i19.3038
Helicobacter species ribosomal DNA in the pancreas, stomach and duodenum of pancreatic cancer patients
Hans-Olof Nilsson, Unne Stenram, Ingemar Ihse, Torkel Wadström
Hans-Olof Nilsson, Torkel Wadström, Department of Laboratory Medicine, Division of Medical Microbiology, Lund University, Lund, Sweden
Unne Stenram, Department of Pathology, Lund University, Lund, Sweden
Ingemar Ihse, Department of Surgery, Lund University, Lund, Sweden
Author contributions: All authors contributed equally to the work
Supported by the Swedish Research Council (16×04723), the Royal Physiographic Society in Lund, Lund University Hospital (ALF), and Gunnar Nilssons Cancerstiftelse
Correspondence to: Dr. Hans-Olof Nilsson, Department of Laboratory Medicine, Division of Medical Microbiology, Lund University, Sölvegatan 23, S-223 62 Lund, Sweden. hans-olof.nilsson@med.lu.se
Telephone: +46-46-173298 Fax: +46-46-189117
Received: November 17, 2005
Revised: November 26, 2005
Accepted: December 1, 2005
Published online: May 21, 2006
Abstract

AIM: To determine whether gastric and enteric Helicobacter species are associated with pancreatic cancer.

METHODS: Patients with exocrine pancreatic cancer (n = 40), neuroendocrine cancer (n = 14), multiple endocrine neoplasia type 1 (n = 8), and chronic pancreatitis (n = 5) were studied. Other benign pancreatic diseases (n = 10) and specimens of normal pancreas (n = 7) were included as controls. Pancreatic tissue specimens were analyzed by Helicobacter-specific PCR-assay and products were characterized by denaturing gradient electrophoresis and DNA-sequencing. From a subset of the pancreatic cancer patients, gastric and/or duodenal tissue as well as gallbladder and ductus choledochus tissue were analyzed. Gallbladder and choledochus samples were included as controls. Stomach and duodenum samples were investigated to analyze whether a gastric helicobacter might disseminate to the pancreas in pancreatic cancer patients. Pancreatic specimens were analyzed by Bacteroides-specific PCR for detecting the translocation of indigenous gut microbes to the diseased pancreas.

RESULTS: Helicobacter DNA was detected in pancreas (tumor and/or surrounding tissue) of 75% of patients with exocrine cancer, 57% of patients with neuroendocrine cancer, 38% of patients with multiple endocrine neoplasia, and 60% of patients with chronic pancreatitis. All samples from other benign pancreatic diseases and normal pancreas were negative. Thirty-three percent of the patients were helicobacter-positive in gastroduodenal specimens. Surprisingly, H. bilis was identified in 60% of the positive gastroduodenal samples. All gallbladder and ductus choledochus specimens were negative for helicobacter. Bacteroides PCR-assay was negative for all pancreatic samples.

CONCLUSION: Helicobacter DNA commonly detected in pancreatic cancer suggests a possible role of the emerging pathogens in the development of chronic pancreatitis and pancreatic cancer.

Keywords: Pancreatic cancer, Helicobacter species, Polymerase chain reaction, DNA-sequence analysis