Int J Radiat Oncol Biol Phys  1996 Jan 1;34(1):161-6 

C-Ki-ras mutations in peripheral blood of pancreatic cancer patients: a marker
for early tumor metastasis.

Mohiuddin M, Ahmed MM, Venkatasubbarao K.

Department of Radiation Medicine, University of Kentucky, Lexington 40536-0084,
USA.

PURPOSE: To determine the incidence of circulating minimal malignant clone
(CMMC) (harboring c-Ki-ras-2 mutation) in peripheral blood (PB) samples of
untreated pancreatic cancer using polymerase chain reaction (PCR) analysis of
c-Ki-ras-2 oncogene. METHODS AND MATERIALS: Experiments were carried out in
fresh tumor, peritoneal washings (PW), and PB samples of untreated pancreatic
adenocarcinoma patients (both resectable and unresectable). Samples were taken
from 16 patients diagnosed with pancreatic adenocarcinoma for the PCR analysis
of mutated c-Ki-ras oncogene. Five tumor samples, 15 PB samples, and 3 PW
samples were analyzed for point mutation of the c-Ki-ras gene at codon 12.
RESULTS: Out of five tumor samples analyzed for c-Ki-ras mutation, four were
positive at the 12th codon. Out of total 15 PB samples, nine were positive for
the c-Ki-ras point mutation at the 12th codon. All the positive PB samples
showed a base substitution from GGT to GAT in the second position of the 12th
codon. Out of three PW samples, two showed mutation at the second position from
GGT to GAT similar to their PB and tumor samples. CONCLUSION: Our study
indicated the presence of the tumor cells (CMMC) in PB of pancreatic
adenocarcinoma that can be identified by PCR analysis of c-Ki-ras oncogene.
Patients with presence of CMMC in PB and mutation in PW had aggressive tumors
that responded poorly to treatment.

PMID: 12118546 [PubMed - indexed for MEDLINE]