Fat clearance of upper gastrointestinal resection specimens increases lymph node yield and may result in nodal upstaging.

INTRODUCTION: Lymph node retrieval and quantification is an important element in staging upper gastrointestinal cancers. Our department introduced fat clearance for oesophagectomy and gastrectomy specimens in 2014. This study assessed the impact of this change on lymph node yield and upstaging.

METHODS: We reviewed histopathology data for upper gastrointestinal resection specimens. Patient demographics, clinical, macroscopic and microscopic data were compared with a historical cohort who did not undergo fat clearance.

RESULTS: Of 158 patients, 133 resection specimens received fat clearance resulting in a significantly higher lymph node yield than the historical cohort (22 vs 13 lymph nodes, p<0.0001). Fat clearance found additional positive nodes in 24.1% of patients and increased the number of cases achieving a minimum node yield of 15. Nodes found by fat clearance caused upstaging in 15% of the cohort.

DISCUSSION: Fat clearance increases node yield in upper gastrointestinal resection specimens and may cause nodal upstaging.