The role of lymphadenectomy in cancer, with particular reference to gastric cancer

Lymphadenectomy has an acknowledged role in the staging of most solid tumors, however, its therapeutic role remains controversial. To date, several prospective, randomized, controlled trials comparing either extended vs. conventional lymphadenectomy (in breast cancer) or prophylactic lymphadenectomy vs observation (in N0 patients with breast cancer or melanoma) have failed to show survival differences between treatment arms. Gastrointestinal cancers, including gastric cancer, represent a special case of this general problem in that intra-abdominal nodes are not clinically accessible and accurate radiographic determination of nodal involvement continues to be problematic. Without question, staging and technical considerations dictate removal of at least some perigastric lymph nodes. However, the one prospective study testing survival benefit for R2 vs R1 lymphadenectomy in gastric cancer was negative. This study suffers from small sample size compounded by post operative pathologic upstaging resulting in entry of a moderate percentage of ineligible patients. Japanese surgeons have also been generally critical of the extent of R2 dissections in Western surgical studies. A second prospective trial, presently underway, addresses these concerns as well as other concerns about selection bias in older retrospective studies and should finally resolve the issue of the therapeutic efficacy of extensive lymphadenectomy in gastric cancer.