Disseminated cancer cells in the blood and expression of sialylated antigen in gastric cancer.
BACKGROUND
In gastric cancer, disseminated cancer cells (DCC) can be detected in peripheral blood using bio-molecular techniques. It is known that patients having DCC exhibit a high occurrence of postoperative relapse in gastrointestinal cancer. However, more than half of gastric cancer patients having positive DCC do not show cancer relapse. Sialylated Lewis antigens are considered to be crucial molecules in the metastasis of disseminated cancer. The current study investigated whether combination analysis of DCC and sialylated Lewis antigen are useful in estimating the recurrence risk of gastric cancer.


METHODS
Subjects were 106 consecutive gastric cancer patients who underwent curative gastrectomy. DCC in the peripheral blood were detected using the carcinoembryonic antigen (CEA)-mRNA by RT-PCR method. Sialylated Lewis antigen expression (sLeA and sLeX) of the primary tumor was assessed immunohistochemically.


RESULTS
Of 106 gastric cancer patients, 43 (40%) were positive for DCC. Immunohistochemically, 53 (50%) and 49 (46%) patients were positive for sLeA and sLeX, respectively. The presence of DCC did not correlate with sLeA and sLeX expression in gastric cancer. Postoperative tumors were present in 19 patients (7 hematogenous and 12 non-hematogenous), 12 of which were positive for DCC. Six sLeA-positive patients (26%) with DCC and 13 sLeX-positive patients (57%) with DCC suffered from postoperative recurrence of gastric cancer. The p value of CEA-mRNA and sLeX combination analysis was more significant (p<0.01) than that of CEA-mRNA alone (p=0.02).


CONCLUSIONS
Analyzing both DCC and sLeX expression in gastric cancer may enable more accurate prediction of postoperative recurrence.
Sumikura
Shin-ichi
S
First Department of Surgery, Kagoshima University School of Medicine, 8-35-1 Sakuragaoka, 890, Kagoshima, Japan.
Ishigami
Sumiya
S
Natsugoe
Shoji
S
Miyazono
Futoshi
F
Tokuda
Koki
K
Nakajo
Akihiro
A
Okumura
Hiroshi
H
Matsumoto
Masataka
M
Hokita
Shuichi
S
Aikou
Takashi
T
D000328:Adult; D000368:Aged; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000032:analysis*; D005260:Female; D006801:Humans; D007983:Lewis Blood Group Antigens; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D009360:Neoplastic Cells, Circulating; D009844:Oligosaccharides / Q000032:analysis*; D000080506:Sialyl Lewis X Antigen; D013274:Stomach Neoplasms / Q000097:blood*
D015295:Antigens, Tumor-Associated, Carbohydrate; D007983:Lewis Blood Group Antigens; D009844:Oligosaccharides; D000080506:Sialyl Lewis X Antigen; C058981:sialyl-Le(a) oligosaccharide