F Hernanz1, E García-Somacarrera, F Fernández. 1. Department of Surgery, Faculty of Medicine, University Hospital Marqués de Valdecilla, Cantabria University, Santander, Spain. cgdhff@humv.es
Abstract
OBJECTIVE: We studied fresh mesenteric and mesorectal tissue after standard dissection of colorectal cancer specimens using a clearing method to evaluate lymph nodes (LN) that could have been missed. METHOD: After traditional dissection, 50 consecutive unfixed residual mesenteric and mesorectal tissues were entirely managed by a new clearing solution, which incorporates hydrochloric acid obtaining a really good degree of fat dissolution, facilitating the identification of missed LNs. RESULTS: By fat clearance, 498 (mean per specimen, 10) additional LNs were found, most of them (83%) varying in size from 1 to 5 mm. and 22 (4.41%) LNs revealed tumour metastases. In two rectal carcinoma specimens that had been treated by neoadjuvant chemoradiotherapy, no LNs were found by traditional dissection; after checking by the clearing method, additional LNs were harvested in both. Three patients were reclassified and upstaged. CONCLUSION: According to our findings, after standard dissection in the remaining mesentery of colorectal specimen there are missed positive LNs, which should be evaluated to avoid pathological understaging.
OBJECTIVE: We studied fresh mesenteric and mesorectal tissue after standard dissection of colorectal cancer specimens using a clearing method to evaluate lymph nodes (LN) that could have been missed. METHOD: After traditional dissection, 50 consecutive unfixed residual mesenteric and mesorectal tissues were entirely managed by a new clearing solution, which incorporates hydrochloric acid obtaining a really good degree of fat dissolution, facilitating the identification of missed LNs. RESULTS: By fat clearance, 498 (mean per specimen, 10) additional LNs were found, most of them (83%) varying in size from 1 to 5 mm. and 22 (4.41%) LNs revealed tumour metastases. In two rectal carcinoma specimens that had been treated by neoadjuvant chemoradiotherapy, no LNs were found by traditional dissection; after checking by the clearing method, additional LNs were harvested in both. Three patients were reclassified and upstaged. CONCLUSION: According to our findings, after standard dissection in the remaining mesentery of colorectal specimen there are missed positive LNs, which should be evaluated to avoid pathological understaging.
Authors: Im-Kyung Kim; Beom Jin Lim; Jeonghyun Kang; Seong-Ah Kim; Dongwon Kang; Seung-Kook Sohn; Kang Young Lee Journal: J Korean Surg Soc Date: 2013-06-26