Purpose: To compare the lymph node yields of lymph node packet submission (PS), packet submission after isolation by surgeons (PSI), and en bloc lymph node submission (EBS) after gastrectomy.
Methods: We conducted a prospective study including 118 gastric cancer patients who underwent gastrectomy between June 2016 and August 2016. We also retrospectively reviewed 607 patients who underwent gastrectomy from May 2015 to May 2016. Following gastrectomy, lymph node specimens were either submitted en bloc (EBS group), divided into packets with accompanying adipose tissue according to the lymph node stations (PS group), or isolated individually based on the surgeon’s visualization and palpation before submission to the Pathology Department (PSI group).
Results: The average lymph node yield was significantly higher in the PSI compared with the PS group in the prospective study (46.5±19.4 vs 31.8±11.1), and significantly higher in the PS compared with the EBS group in the retrospective study (31.5±12.6 vs 23.9±8.9) (both P<0.001). There was no significant difference in positive lymph node yields in either of these comparisons (prospective study, P=0.581; retrospective study, P=0.489). The survival curve indicated no significant difference between the PS and PSI groups (log rank P=0.957); however, these three groups share different lymph node ratio (LNR).
Conclusion: PSI could yield more lymph nodes than PS or EBS with a lower LNR at pathological examination. However, the difference in lymph nodes harvested had no impact on survival, which may need further investigation.
Keywords: lymph node retrieval, lymph node, gastric cancer, gastrectomy, cancer staging