CLINICOPATHOLOGICAL SIGNIFICANCE OF KI-RAS POINT MUTATION AND P21 EXPRESSION IN BENIGN AND MALIGNANT EXOCRINE TUMORS OF THE HUMAN PANCREAS

Conclusion. The present study suggests that Ki-ras point mutations may play an important role in the early stages of tumorigenesis and that a double mutation has a stronger detrimental effect than a single muta tion on the survival after pancreatectomy. Background. Previous studie s have suggested the important role of Ki-ras point mutations in ras g ene codon 12 in the tumorigenesis of pancreatic cancer, but their clin icopathological significance is still unclear. The present study was d esigned to assess the clinicopathological significance of Ki-ras point mutations, and p21 expression in malignant and benign diseases of the pancreas. Methods. Oligonucleotide dot-blot hybridization for Ki-ras point mutations in codon 12 and immunohistochemical staining for p21 e xpression were applied. Cases included 44 primary and 15 metastatic le sions of pancreatic cancer, and 17 benign pancreatic diseases. Results . Ki-ras point mutations and p21 expression were detected in 43 and 19 primary lesions, 9 and 6 metastatic lesions, and four and five benign diseases, respectively. The patients with a single mutation had a bet ter survival after pancreatectomy than those with a double mutation. T he patients with a p21(+) GAT mutation showed the worst survival after pancreatectomy compared with other categories of patients.