Does extended lymphadenectomy influence prognosis of gastric carcinoma after curative resection?

Background/Aims:It is unclear whether gastric cancer prognosis is improved by extended lymph node dissection more than by lymph node dissection limite d to the contiguous N1 perigastric lymph nodes. Methodology: Four hundred and thirty-eight patients treated by curative gas trectomy were evaluated. Outcomes of D1/D1.5 lymphadenectomy, limited lymph node dissection and of D2/D2.5 lymphadenectomy, extended lymph node dissec tion and histopathological prognostic factors as in the 1993 TNM staging cl assification supplement were analyzed. Results: Estimated overall 5-year survival was 54.9%. Five-year survival wa s 58.4% in the limited lymph node dissection group and 54% in the extended lymph node dissection (P n.s.), Stage I 5-year survival was 59% after D2.5 lymph node dissection, 58% after D1.5 and 50% after D2 dissection (P n.s.). Stage II 5-year survival was 86% in D2.5 group and 56% in D1.5 group (P = 0.041). Stage ma survival was 61% in the D2.5 group and 22% in the D1.5 gro up (P = 0.001). Stage IIIb 5-year survival was 42% after D2.5 resection:and 0% in D1.5 group (P = 0.001). In the pT3 group 5-year survival was 72% aft er D2.5 dissection and 33% after D2 dissection (P = 0.001). In the positive N1 lymph nodes group 5-year survival was better after extended lymph node dissection than after limited lymph node dissection. In pN2a patients 5-yea r survival was 57% after D2.5 resection and 0% after D2 resection (P < 0.00 1). In pN2b and pN2c patients extended:lymph node dissection did not statis tically improve survival. Conclusions: Even if no statistical differences were found in overall survi val, prognosis was improved by extended lymph node dissection in stage II a nd III, particularly ih T2 and T3 subgroups and in N1 and N2a subgroups. Wh en large numbers of positive nodes:were found, improved survival was depend ent upon resection, of extragastric nodes distal to the uppermost echelon o f positive nodes.