THE EFFECT OF LYMPH NODE DISSECTION ON THE DEVELOPMENT OF METACHRONOUS PERITONEAL DISSEMINATION AFTER GASTRIC CANCER RADICAL TREATMENT

Abstract

Background. Metachronous peritoneal dissemination (MPD) is a prevailing pattern of gastric cancer (GC) progression, significantly aggravating the outcomes of its radical treatment. As intraperitoneal dissemination of tumor cells can occur during lymphodissection (LD), it is essential to assess its influence on the development of MPD. Objective. To evaluate the influence of LD volume on MPD development in patients radically operated on for cancer. Material and methods. There have been analyzed the outcomes of 1080 patients radically operated on for cancer (pT1-4N0-3M0) without esophageal transition (647 men, 433 women) depending on the volume of LD performed - D1 (n=151) or D2 (n=929). Survival rates (Kaplan-Meier multiplier estimation method), cumulative incidence (CI) of competing events - MPD, metastases of other localization, mortality not related to gastric cancer were estimated (competing risks analysis). Results. There has been demonstrated the possibility of intraoperative dissemination of tumor cells during LD in the presence of metastatic changes of regional lymphocollectors and in the absence of adjuvant treatment, it being manifested by the increase of cumulative incidence of MPD only (for patients after D1 LD - from 8,3±2,8% at pN0 to 29,1±6,2% at pN1-3 (pGray<0,05); for patients after D2 LD - from 9.4±1.3% at pN0 to 27.3±2.1% at pN1-3 (pGray<0,05)), and in combination with other distant lymphohematogenic metastases (for patients after D1 LD, from 0 at pN0 to 1.8±1.8% at pN1-3; for patients after D2 LD, from 3.1±0.8% at pN0 to 11.1±1.5% at pN1-3 (pGray<0,05)). Conclusions. The evaluation of regional lymphatic collectors state seems to be reasonable when assessing the probability of MPD development. The type of LD performed does not affect the CI of GC progression including MPD development.