Prognostic significance of isolated tumor cells in regional lymph nodes in patients with T2-T3 stage gastric cancer.

8 Background: The prognostic impact of isolated tumor cells (ITCs) in regional lymph nodes is unclear. This study was aimed to evaluate the prognostic significance of ITCs in subpopulation with T2-T3 gastric cancer by adopting the standard definition for ITC (≤ 0.2 mm, detected by H&E or IHC) and micrometastsis (≤ 2 mm, detected by H&E or IHC) in 7th AJCC staging. Methods: A total of three hundred eleven patients diagnosed as pT2-3/N0-2/M0 gastric carcinoma after curative surgery at Korea Cancer Center Hospital between January 1996 and December 2000 was retrospectively studied. All tumor and lymph node specimens by H&E received reexaminations, and 5,825 lymph nodes from 191 patients without macrometastasis (> 2.0 mm) were re-evaluated after IHC staining with anti-cytokeratin (AE1/AE3). And N stage was reclassified into pN0(i-), pN0(i+), pN1mi, pN1, and pN2. Survival analyses were performed using Kaplan-Meier method with Log-rank test and Cox regression model. Results: According to original N stage, 5-year...