Optimal lymph node dissection for gastric cancer: a narrative review.

The management of gastric cancer has long been debated, particularly the extent of lymph node (LN) dissection required during curative surgery. LN invasion stands out as the most critical prognostic factor in gastric cancer. Historically, Japanese academic societies were the pioneers in defining a classification system for regional gastric LN stations, numbering them from 1 to 16. This classification was later used to differentiate between different types of LN dissection, such as D1, D2 and D3. However, these definitions were often considered too complex to be universally adopted, resulting in wide variations in recommendations from one country to another and making it difficult to compare published studies. In addition, the optimal extent of LN dissection remains uncertain, with initially recommended dissections being extensive but associated with significant morbidity without a clear survival benefit. The aim of this review is to make a case for extending LN dissection based on the existing literature, which includes a comprehensive examination of the current definitions of lymphadenectomy and an analysis of the results of all randomised controlled trials evaluating morbidity, mortality and long-term survival associated with different types of LN dissection. Finally, we provide a summary of the various recommendations issued by organizations such as the Japanese Gastric Research Association, the National Comprehensive Cancer Network, the European Society for Medical Oncology, and the French National Thesaurus of Digestive Oncology.