Extended lymph node dissection, a treatment for gastric cancer

Extended lymph node dissection – a treatment for gastric cancer involving the surgical removal of lymph nodes near the tumor, in distant areas of the stomach, and in some cases, in combination with the removal of the spleen and pancreas tail – has shown no long-term survival benefit for gastric cancer patients, according to the largest randomized trial of limited and extended lymph node dissection among this population. Gastric cancer is the fourth most common type of cancer worldwide and is diagnosed in approximately 870,000 people annually.

An accompanying editorial states that these definitive study findings resolve a major debate in the surgical oncology community over the benefit of extended lymph node dissection among gastric cancer patients. Both the study and editorial will be published online April 12 in the Journal of Clinical Oncology (JCO).

“Long-term follow up of limited and extended lymph node dissection clearly demonstrates that neither improved survival nor decreased relapse rates can be obtained by extended dissection,” said H. H. Hartgrink, MD and lead author of the study. “In fact, extended lymph node dissection may even be harmful because of increased morbidity and hospital mortality associated with the procedure.”

While overall incidence of the disease is declining, it remains an major cause of death worldwide. Surgery is the only possible curative treatment for gastric cancer, and results of gastrectomy – the surgical removal of all or part of the stomach – have improved significantly over the years with respect to survival, morbidity, and post-operative mortality. However, researchers have long debated whether the wider resection of lymph nodes involved in extended lymph node dissection has contributed to this improvement. The debate has particular relevance in Japan, where there are high rates of gastric cancer and the procedure is used extensively.

To address this question, researchers at the Leiden University Medical Centre in the Netherlands compared the morbidity, mortality, long-term survival, and cumulative risk of relapse of a limited (D1) lymph node dissection to an extended (D2) lymph node dissection for gastric carcinoma in a randomized trial.

A total of 1078 patients with gastric adenocarcinoma were randomized to undergo D1 or D2 dissection, of which 711 patients were treated with curative intent (82 patients were ineligible and 285 received palliative treatment). After 11 years, researchers found no significant survival benefit for either group. Postoperative mortality (death within 30 days after operation) occurred in 10% of patients in the D2 group, compared to 4% of patients who underwent limited lymph node dissection. Similarly, morbidity associated with the surgery was higher among patients in the D2 group – 43% of patients compared to 25% in the D1 group. Results from this trial indicate definitive data on the procedure, confirming results published previously.

Researchers concluded that extended lymph node dissection generated no long-term survival benefit, noting that the associated higher postoperative mortality may have offset any long-term effect in survival.

They noted that morbidity and mortality were greatly influenced by the extent of lymph node dissection, the removal of the pancreas or spleen, and the patient’s age, and that the surgery with extended lymph node dissection may only be of benefit if morbidity and mortality can be avoided.

An accompanying editorial praised the study, noting that “the debate over performing a D1 or D2 lymphadenectomy for gastric cancer should be put to rest.”

“Clinical and scientific research teams of surgical, medical and radiation oncologists should concentrate their efforts on training surgical residents and fellows to perform a complete D1 lymphadenectomy, developing new agents for neoadjuvant and adjuvant clinical trials of gastric cancer and improving radiation techniques,” said Nicholas J. Petrelli MD, editorial author and MBNA Medical Director of the Helen F Graham Cancer Center and Professor of Surgery at Thomas Jefferson University.

“These areas, along with the explosion in genomic medicine, are the future hope for patients with gastric cancer,” he added.

"Extended lymph node dissection for gastric cancer; who may benefit?” H.H. Hartgrink, et al., Leiden University Medical Center, The Netherlands.

The Journal of Clinical Oncology is the semi-monthly peer-reviewed journal of the American Society of Clinical Oncology (ASCO), the world’s leading professional society representing physicians who treat people with cancer.