Lymph node microinvolvement in adenocarcinoma of the gastro-esophageal junction

Abstract

Introduction: In the past decade there has been a alarming rise in the incedence of adenocarcinoma of the gastro-esophageal junction in western countries. There at present time still much discrepancies in the classification of tumors of the gastro-esophageal junction.We investigated possible differences and the prognostic impact of lymph node microinvolvement and micrometastases in adenocarcinoma of the gastro-esophageal junction . Material and methods: We examined in 3987 lymph nodes of 145 ROresected adenocarcinoma of the gastro-esophageal junction with irnmunhistochemical techniques (antibody cocktail AEl/AE3 and antibody BerEP4) the incidence of micrometastases and microinvolvement. Micrometastases were defined as single tumor cells or cellclusters smaller than 0.2mm in diameter with stromal reaction, classified as microinvolvement when the stromal reaction was missed. Results: In 90 (2.3%) of the lymph nodes microinvolvement and in 106 (2.7%) micrometastases were detectable.Of the 145 investigated patients, 75 were classified as pNO and 70 patients had lymph node metastases in standard histological examination. In contrast to the pNOpatients showed the pN+ patients significant more micrometastases (17.3% vs. 60%); p<0.05). The presence of lymph node micrometastases correlated with the pT-stade and the non-intestinal classification according to Lauren. Patients with true cardia carcinoma and subcardial carcinoma showed a significant higher rate of micrometastases than adenocarcinoma of the distal esophagus (24.4% vs. 6.7%; p<0.05). The survival analysis showed a significant difference between pNO staged patients with micrometastases compared to patients without micrometastases. The microinvolvement was without impact on survival. Conclusion: In contrast to adenocarcinoma of the distal esophagus, patients with true cardia carcinoma and subcardial carcinoma had a higher incidence of micrometastases. This request a more specialized classification of adenocarcinoma of the gastro-esophageal j unction and supports the different surgical extension and lymphadenectomy in this tumor entities.