Clinical Significance of Lymph Node Micrometastasis on Patients with pT_(1-3)N_0 Gastric Cancer / 中国普外基础与临床杂志

ABSTRACT

Objective To investigate the lymph node micrometastasis and its clinicopathologic features on 5-year disease free survival rate for patients with pT1-3N0 gastric cancer.Methods One hundred and twenty patients with stage pT1-3N0 gastric tumors were included,and 2 106 lymph nodes were harvested and examined in all the specimens.There were 9-28 lymph nodes with average 18 lymph nodes from each patient.All the lymph nodes were negative by HE staining.The CK20 expression of lymph nodes was tested by immunohistochemistry.The relationships between clinicopathologic features or CK positive expression and 5-year disease free survival were analyzed.Results The positive expression rate of CK20 was 9.07%(191/2 106)in lymph nodes and 26.67%(32/120)in patients with pT1-3N0 gastric cancer by immunohistochemistry.Eleven cases were with micriometastasis,21 cases were isolated tumor cells(ITC).The average postoperative follow-up was 66.35(range 24-121)months.Five-year disease free survival rates were 87.4%,78.3%,and 40.9% for the lymph node negative,ITC,and micrometastasis groups,respectively.Five-year disease free survival rate in the micrometastasis group was lower than that in the lymph node negative group(P=0.000)and ITC group(P=0.046).However,there was no significant difference between the lymph node negative group and ITC group(P=0.253).Multivariate analysis identified tumor diameter(P=0.011),depth of tumor invasion(P=0.043),and lymphatic vessel invasion(P=0.002)were related with CK20 positive expression.There was no significant relationship between the pathologic parameters and the 5-year disease free survival rates.Lymph node micrometastasis of gastric cancer was detected in 11 patients who should belong to stage pN1(Mi),the restage rate was 9.17%.While the lymph node negative(88 patients)and ITC(21 patients)were recorded pN0(i-)and pN0(i+),respectively,and were not recommended restage(stage pN0).Conclusion Patients with stage pT1-3N0 gastric cancer and micrometastasis in lymph node are with high-risk and low 5-year disease free survival rate,for whom adjuvant therapies may be justified and effective.