Effect of xylene clearance of mesenteric fat on harvest of lymph nodes after colonic resection

Eur J Surg. 1994 Dec;160(12):693-7.


Objective: To find out if clearance of surgical colectomy specimens with xylene gave a higher yield of lymph nodes and more accurate staging than the traditional step-sectioning technique.

Design: Consecutive open study.

Setting: Private hospital, United States.

Material: 84 specimens from colonic resections, 4 of which were total colectomies and the remaining 80 segmental resections.

Interventions: The first 41 (2 colectomies and 39 segmental resections) were cleared by step-sectioning alone (to establish baseline values). The remainder (n = 2 and 41, respectively) were step-sectioned, the lymph nodes were removed, and then the residual tissue was cleared with xylene.

Main outcome measures: The number of lymph nodes found, and if the diagnosis was changed by the finding of additional nodes.

Results: The baseline values in the two total colectomy specimens were 76 and 101, and the mean (range) after segmental colectomy was 21 (1-98). The values after total colectomy in the second group were 33 and 73, and after xylene clearance an additional 12 and 17 nodes were found. After segmental colectomy a mean (range) of 13 (0-43) was found, and an additional 4 (0-12) were found after xylene clearance. No additional nodes containing metastases were found in total colectomy specimens after xylene clearance, and only 6 additional nodes after segmental resection contained metastases. These changed the histological stage of the disease in only 2 patients.

Conclusions: Xylene clearance offers little advantage over careful traditional step-sectioning of specimens, but may be of value if the histopathologist does not do routine meticulous step-sectioning.

MeSH terms

  • Case-Control Studies
  • Colorectal Neoplasms / pathology*
  • Colorectal Neoplasms / surgery
  • Histocytological Preparation Techniques*
  • Humans
  • Lymph Nodes / pathology*
  • Lymph Nodes / surgery
  • Lymphatic Metastasis / diagnosis
  • Mesentery / pathology*
  • Mesentery / surgery
  • Neoplasm Staging
  • Prospective Studies
  • Xylenes*


  • Xylenes