Intrahepatic micrometastases around liver metastases from gastric cancer.
OBJECTIVE
We aimed to clarify the association between the presence of micrometastases around liver metastases from gastric cancer and the results of hepatic resection. In addition, we investigated the influence of E-cadherin and matrix metalloproteinase (MMP)-7 expression on the development of micrometastases.


METHODS
Micrometastases around liver metastases were examined microscopically in 31 metastatic liver tumor specimens resected from 17 patients who had undergone hepatic resection for liver metastases from gastric cancer. E-cadherin and MMP-7 expression in the primary gastric tumor, the liver metastases, and the micrometastases were examined immunohistochemically.


RESULTS
Hepatic micrometastases were present in around 48% of the liver metastases, accounting for 59% of the patients. The tumor recurrence rate in the remnant liver after hepatic resection was significantly higher, and survival significantly poorer, in patients with such micrometastases than in those without. Micrometastases tended to appear around the liver metastases that had reduced E-cadherin expression. Most of the micrometastases in the lymph ducts and sinusoids showed reduced E-cadherin expression. MMP-7 expression was not correlated with the presence of micrometastases.


CONCLUSIONS
About half of the hepatic metastases from gastric cancer had seeded off micrometastases, and the presence of these micrometastases was associated with a poorer result of hepatic resection. Reduced E-cadherin expression in metastatic liver tumors may be associated with the development of micrometastases.
Department of Gastroenterological and General Surgery, Yamagata University School of Medicine, 2-2-2 Iida-Nishi, Yamagata, 990-9585, Japan.
Takashi
T
Nomura
Yukinori
Y
Kamio
Naoki
N
Takasu
Toshiyuki
T
Moriya
Akiko
A
Takeshita
Masaomi
M
Mizutani
Osamu
O
Hachiya
Ichiro
I
Hirai
Wataru
W
Kimura
D000328:Adult; D000368:Aged; D015820:Cadherins / Q000378:metabolism; D017024:Chemotherapy, Adjuvant; D018450:Disease Progression; D005260:Female; D006498:Hepatectomy; D006801:Humans; D007150:Immunohistochemistry; D008113:Liver Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000556:secondary* / Q000601:surgery; D008297:Male; D020783:Matrix Metalloproteinase 7 / Q000378:metabolism; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology; D011169:Portal Vein / Q000473:pathology; D013274:Stomach Neoplasms / Q000473:pathology*
D015820:Cadherins; D020783:Matrix Metalloproteinase 7