Efficacy of the fat-dissociation method for nodal harvesting in gastric cancer

BACKGROUND: There is an increased need for accurate staging for gastric cancer treatment. Consequently, it is necessary to carefully examine all dissected lymph nodes for precise staging. Recently, the fat-dissociation method has been developed as a quick and accurate method for harvesting dissected lymph nodes of colorectal cancer cases. AIM: To investigate the usefulness of the fat-dissociation method for harvesting dissected lymph nodes of gastric cancer cases. METHODS: Fifty-six resected specimens from gastric cancer patients who underwent standard curative gastrectomy and lymph node dissection at our hospital were used. Group 2 lymph nodes were separated from each specimen, and the remaining adipose tissue containing the group 1 lymph nodes was used. Some resected specimens were subjected to the fat-dissociation method. One vial of Imofully(®) was dissolved in 50 mL of saline and injected into the tissue. The tissue was incubated for 1 h and the dissolved fat was removed. Subsequently, the nodes were identified, picked up with scissors, and mapped. The number of nodes in each lymphatic compartment and duration of lymph node harvest and mapping were compared. RESULTS: The fat-dissociation method was used for 24 samples, while the conventional dissection method was used for 32 samples. The total number of harvested lymph nodes was 45.9 in the fat dissociation group and 44.3 in the control group, and there was no significant difference between the two groups. There were also no significant differences in the number of lymph nodes between the two groups based on a comparison of the lymphatic compartments. However, the total median duration of the fat-dissociation method was 38.2 min, reflecting a reduced duration of approximately 60 min compared to the control group. CONCLUSION: Based on our results, the fat-dissociation method is effective in shortening the duration of lymph node harvest in gastric cancer surgery.