[Modified radical lymph node dissection in the treatment of gastric cancer invading the gastric serosa].

The improvement in prognosis for patients with advanced gastric cancer may be attributable to the success of the extensive lymph node dissection and adjuvant anticancer chemotherapy. In the present study, however, we found that the postoperative long-term prognosis for patients with gastric cancer invading the gastric serosa was not improved even by more extensive lymph node removal (R3-removal) than secondary lymph node removal (R2-removal). This difference indicates that serosal invasion by cancer, which is a source of exfoliating cancer cells and is closely related to peritoneal metastasis, is another factor influencing the prognosis of gastric cancer patients. Actually, in patients with gastric cancer who had serosal invasion, free cancer cells were frequently detected in the peritoneal cavity by means of pelvic lavage. We introduced continuous hyperthermic peritoneal perfusion (CHPP) with an anticancer drug as a prophylactic treatment for peritoneal recurrence after surgery for gastric cancer. In the randomized control study, the cumulative 5-year survival rate of patients in the CHPP group was better than that of the control group, although there was no significant difference. Based on the above, we suggest that in gastric cancer with serosal invasion, selective removal of Group 3 lymph nodes according to the location of the primary cancer lesion (modified radical lymph node dissection) and prophylactic treatment for peritoneal metastasis promise better outcome.