Polymerase Chain Reaction-Based K-rasMutation Detection of Pancreatic Adenocarcinoma in Routine Cytology Smears

Abstract

P o l y m e r a s e C h a i n R e a c t i o n -B a s e d K -r a s M u t a t i o n D e t e c t i o n o f P a n c r e a t i cA d e n o c a r c i n o m a i n R o u t i n e C y t o l o g y S m e a r s

K-ras Oncogene Mutations Indicate Malignancy in Cystic Tumors of the Pancreas

“…Approximately 85% of ductal pancreatic adenocarcinomas contain K-ras mutations.3234 By far, the majority of K-ras mutations occur at codon 12, although codon 13 and 61 mutations have rarely been detected.33'34 Endocrine pancreatic tumors usually do not carry K-ras mutations.35 K-ras mutations lead to uncontrolled cell growth and are thought to be an early event in exocrine pancreatic tumorigenesis. The high frequency of K-ras mutations in ductal adenocarcinoma, coupled with the fact that such mutations can be identified in fine-needle aspirates, routine cytologic smears, pancreatic and duodenal juice, and stool specimens, makes analysis for K-ras mutations an appealing diagnostic [36][37][38][39][40][41] test.-However, the role of K-ras mutations in cystic pancreatic tumors has yet not been determined, because only a few cases have been analyzed in the world literature. The only exception is the intraductal papillary mucinous tumor of the pancreas, considered a low-grade malignancy.…”

Utilization of polymerase chain reaction on archival cytologic material: a comparison with fresh material with special emphasis on cerebrospinal fluids

“…6,9,[20][21][22] This has been achieved in small numbers with PCR tests for the diagnosis of lymphomas 5,7,11,23 and also in a small number of CSF studies. 10,14 In all references mentioned, the PCR tests performed on the cytologic material was found to provide important diagnostic information that was, in some instances, not possible by morphology alone.…”

“…Several small series have shown, however, that archival cytologic samples and formalin-fixed tissues may be suitable for evaluation by molecular tests. [4][5][6][7][8][9][10] This principle may be extremely important when a diagnosis is unsuspected and when fresh tissue is no longer available, as well as for the testing of remotely obtained samples.…”

The potential diagnostic use of K-ras codon 12 andp53 alterations in brush cytology from the pancreatic head region

“…[5][6][7][8][9][10][11][12] Previous studies have demonstrated K-ras and p53 alterations in material collected in various ways from the pancreatic head region and have found that these genetic alterations can be used as tumour markers with high sensitivity and specificity. [13][14][15][16][17][18][19][20] However, most of these studies were performed on small study groups; a definitive tissue diagnosis was often not available; and comparison of these genetic alterations in the cytology specimen and in the corresponding carcinomas was often not included. These limitations make it impossible to determine the rate and causes of false-positive and false-negative outcomes.…”