Correlation between microsatellite instability and metachronous disease recurrence after endoscopic mucosal resection in patients with early stage gastric carcinoma
A. Kawamura et al., Correlation between microsatellite instability and metachronous disease recurrence after endoscopic mucosal resection in patients with early stage gastric carcinoma, CANCER, 91(2), 2001, pp. 339-345
BACKGROUND. Since endoscopic treatment was first evaluated and established
as a treatment for patients with early stage gastric carcinoma, metachronou
s disease recurrence at other sites in the stomach after endoscopic treatme
nt has become a major problem.
METHODS. A retrospective case-control study was conducted on 10 patients wi
th metachronous recurrence of gastric carcinoma after undergoing successful
endoscopic mucosal resection (EMR) therapy for early stage gastric carcino
ma and on 14 patients without recurrence. Gastric mucosal tissues obtained
during the initial EMR were dissected, and DNA samples from the tumor tissu
e and surrounding nonneoplastic mucosa were extracted separately, Microsate
llite instability (MSI) was tested in five microsatellite markers (D2S137,
D3S1067, TP53, TGF beta RII, and BAX) The authors also looked for K-ras cod
on 12 point mutations in the tumor tissues. In addition, immunohistochemica
l staining was done to test for the presence of proliferating cell nuclear
antigen (PCNA), p53, hMSH2, and hMLH1 in the mucosal tissues. Finally, the
correlation between the presence or absence of metachronous recurrence and
the characteristics of the primary tumor (MSI, K-ras, p53, etc.) were inves
tigated.
RESULTS, Three of 10 patients with recurrent disease showed MSI in more tha
n two microsatellite markers among 3-5 investigated site (MSI-H), whereas n
one of the patients with nonrecurrent disease did so. There was no signific
ant correlation between metachronous recurrence after EMR and immunohistoch
emical staining reactions, including those for PCNA, p53, hMSH2, and hMLH1.
None of the patients showed K-rns mutations.
CONCLUSIONS, Thirty percent of patients with recurrent disease showed MSI-H
, whereas none of the patients with nonrecurrent disease did so. (C) 2001 A
merican Cancer Society.