OBJECTIVETo investigate the evaluation of lymphatic emboli by D2-40/CKpan dual immunostain and its prognostic significance in advanced primary gastric adenocarcinoma.

METHODSTissue samples of 108 cases of advanced gastric adenocarcinoma with radical gastrectomy were collected from Chinese PLA General Hospital in 2001. Lymphatic emboli were evaluated by D2-40/CKpan dual immunostain on consecutive sections, and compared with routine HE staining. The correlation of lymphatic emboli with lymph node metastasis and overall survival was analyzed by Pearson Chi-squared test and univariate survival analysis, respectively.

RESULTSLymphatic emboli were detected in 73/108 (67.6%) cases by D2-40/CKpan staining, compared to 57/108 (52.8%) by HE staining. There was significant difference (P=0.007). Lymphatic emboli on HE staining revealed false negative in 24/108 cases and false positive in 8/108 cases. A significant correlation was found between lymphatic emboli and lymph node metastasis on HE staining (P=0.024), while it was not found on D2-40/CKpan staining (P=0.422). The overall survival rate was significantly different between lymphatic emboli positive and negative cases on HE staining (P=0.043). The overall survival rate was lower in lymphatic emboli positive cases on HE staining. Lymphatic emboli evaluated on D2-40/CKpan staining had no prognostic value (P=0.402).

CONCLUSIOND2-40/Ckpan dual immunostaining is more sensitive for lymphatic emboli in gastric adenocarcinoma but may not predict lymph node metastasis and survival, while HE staining may.