Background/aims: We want to estimate the feasibility of lymphatic marking and clinical significance of sentinel node biopsy for colon and gastric cancer. The goal of the present article is to contribute to surgical treatment individualization and early discovering of micro-metastases for digestive system carcinomas using a sentinel node biopsy.
Methodology: The prospective clinical trail included 116 operated patients, 60 with colon cancer, and 56 with gastric cancer admitted to Surgery Clinic "dr Dragisa Misovic" in Belgrade. Sentinel lymph-node mapping is being performed by subserous injection 1% of Lymphazurin.(colon "ex vivo", and gastric "in vivo"). Ultra-staging by immunohistochemical analysis was performed in those SLN which did not have metastases (stained with standard H-E method- negative). Then, these results were analyzed and correlated with lymphonodal status and clinicopathological factors.
Results: Sentinel lymph nodes (SLN) were successfully identified in 58 (96.64%) cases of colon cancer and 100% in cases of gastric cancer. Total number of identified SLN accounted for 428, of which 232 (4.14 per patient) for colon, and 196 (3, 54 per patient) for gastric cancer. Aberrant lymph drainage is more frequent in colon cancer (23.8%) than in gastric (14.3%). In 26 cases with metastases negative colon SLN immunohistochemical (IHC) analysis was done, and in 26.9% micro-metastases were present. When it comes to gastric cancer 62.5% (128.4) SLN were metastatically changed, and metastases were found in non-SLN only in cases when SLN were positive, which means that "skip" metastases were not identified in neither cases. In 37.5% gastric cancers there were no metastases at standard histopathological examination, but IHC analysis determined the presence of micro-metastases in 38.09% or 8 patients. Multivariate analysis shows the SLN metastases frequency of pT3/ pT2; Odds ratio 4,836. The sensitivity of the SLN biopsy in diagnosis of the lymph node status was 100%.
Conclusions: Sentinel nodes biopsy using 1% lymphazurin in colon and gastric cancer is a feasible method with very high sensitivity and specificity (100%). Intraoperative diagnosis of SLN micrometastases is a crucial for planning the operation and more over in determine of adjuvant therapy because SLN biopsy permit more rigorous and precise pathological analysis which colud lead to up staging from I or II to III stadium. Minimally invasive surgical techniques must be preceded by SLN biopsy.