CARNOY’S SOLUTION INCREASES LYMPH NODES COUNT IN COLON CANCER SPECIMENS WHEN COMPARED TO FORMALIN FIXATION: A RANDOMIZED TRIAL

ABSTRACT - BACKGROUND: At least 12 lymph nodes (LNs) should be examined following surgical resection of colon cancer. As it is difficult to find small LNs, fat clearing fixatives have been proposed, but there is no consensus about the best option. AIM: The objective of this study was to verify if Carnoy’s solution (CS) increases the LN count in left colon cancer specimens. METHODS: A prospective randomized trial (clinicaltrials.gov registration: NCT02629315) with 60 patients with left colon adenocarcinoma who underwent rectosigmoidectomy. Specimens were randomized for fixation with CS or 10% neutral buffered formalin (NBF). After dissection, the pericolic fat from the NBF group was immersed in CS and re-dissected (Revision). The primary endpoint was the total number of LNs retrieved. RESULTS: Mean LN count was 36.6 and 26.8 for CS and NBF groups, respectively (p=0.004). The number of cases with