How to optimize lymph node examination in colorectal carcinomas. An easy and effective fat clearance technique

Studies relating to the prognosis of colorectal carcinomas insist on the qu ality of mesocolic examination and on the frequency of metastases in minute lymph nodes. The aim of our study was to evaluate an easy, rapid and new c learance method recently described by Koren et al. Twenty-one surgical spec imens for colorectal carcinomas have been investigated. After lymph node ex amination with the traditional method, the mesocolic fat was immersed in a clearing solution. After 6 hours, lymph nodes stood out as white chalky nod ules, and were dissected. By the traditional method 182 lymph nodes were de tected and 89 additional lymph nodes after clearing. In one case, the detec tion of a metastase in lymph node after clearing allowed to upstage the tum our from Dukes B (N0) to Dukes C (N+). This easy and inexpensive method all ows the detection of minute lymph nodes and helps to establish a more accur ate staging.