Vai trò của nhuộm hóa mô miễn dịch CK(AE1/AE3) trong phát hiện hạch di căn kín đáo ung thư biểu mô tuyến dạ dày

Abstract

This cross-sectional descriptive study aimed to evaluate the role of immunohistochemistry (IHC) using cytokeratin (CK) (AE1/AE3) in the detection of occult D2 lymph node metastases in patients with gastric adenocarcinoma who underwent curative surgery at Hanoi Medical University Hospital from January to December 2024. A total of 3,072 lymph nodes from 110 patients were examined. Compared with conventional hematoxylin and eosin (H&E) staining, IHC detected an additional 108 occult lymph node metastases, accounting for 3.5% of the total lymph nodes, resulting in an increase of 12.7% in the number of patients with occult metastases and allowing pathological N (pN) stage upstaging in 10.9% of patients. The detection rate of occult lymph node metastases increased significantly with advancing pT stage (pT1–pT4) (p < 0.001). Tumors larger than 30 mm were associated with a significantly higher rate of occult lymph node metastases compared with tumors ≤ 30mm (p = 0.025). Conclusion: Immunohistochemistry with cytokeratin (AE1/AE3) significantly improves the detection of occult D2 lymph node metastases in patients with gastric adenocarcinoma compared with routine H&E staining (McNemar test, p < 0.01). This method may contribute to more accurate pN staging and reduce the risk of missing patients who may benefit from adjuvant therapy after surgery. The prevalence of occult lymph node metastases increases with tumor T stage (p < 0.001) and primary tumor size (p = 0.025). These findings suggest that the additional use of CK(AE1/AE3) immunohistochemistry may be particularly useful in patients with advanced-stage gastric adenocarcinoma and large primary tumors (> 30mm) without lymph node metastases detected on H&E staining, in order to minimize the risk of missing occult lymph node metastases.