[Frequency of K-ras mutation in biliary and pancreatic tumors].
BACKGROUND
The ras gene family (H-ras, N-ras and K-ras) are oncogenes that mutate frequently in human cancer, specially in tumors of the biliary tract and pancreas.


OBJECTIVE
To determine the frequency of K-ras gene codon 12 mutation in pancreatic and biliary tumors.


METHODS
Samples of 35 gallbladder, 15 ampulla of Vater, 10 biliary tract and 9 pancreatic tumors, were analyzed. The tumor tissue was microdissected from paraffin embedded biopsies. The mutation was detected by a combination of polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP).


RESULTS
Overall, 46% of samples had K-ras gene mutations. Mutation frequency was 80, 56, 50 and 29% for ampulla of Vater, pancreatic, biliary tract and gallbladder tumors, respectively. When compared with the rest, gallbladder tumors had a significantly lower frequency of the mutation. Median survival for biliary tract tumors was 6 months, compared with 65 months for gallbladder tumors (p <0.05).


CONCLUSIONS
Gallbladder carcinoma had the lower frequency of K-ras mutation, when compared with pancreatic, biliary tract and ampulla of Vater tumors.
Roa
Juan Carlos
JC
Departamento de Anatomía Patológica, Facultad de Medicina, Universidad de la Frontera. jcroa@ufro.cl
Anabalón
Leonardo
L
Tapia
Oscar
O
Melo
Angélica
A
de Aretxabala
Xabier
X
Roa
Iván
I
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D003062:Codon; D005260:Female; D005706:Gallbladder Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D011905:Genes, ras / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D010190:Pancreatic Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D012737:Sex Factors; D016019:Survival Analysis
D003062:Codon