Cutting down cancer � more is less

Extended lymph node dissection increases mortality to
an unacceptable level in gastric cancer

By Chris Williams

"The debate is over; it's time to move on" was the assessment prompted by a study published April 12 in the online edition of Journal of Clinical Oncology. The authors feel that the study has laid to rest the long-running controversy over the benefit of extended lymph node dissection in gastric cancer treatment.

Extended lymph node dissection, which can involve the removal of the spleen and pancreas as well, has shown no long-term survival benefit for gastric cancer patients, according to the largest randomized trial yet.

"Long-term followup of limited and extended lymph node dissection clearly demonstrates that neither improved survival nor decreased relapse rates can be obtained by extended dissection," said the study's lead author Dr H Hartgrink of the Leiden University Medical Center in the Netherlands. "In fact, extended lymph node dissection may even be harmful because of increased morbidity and hospital mortality associated with the procedure."

This is big news because, while overall incidence of the disease is declining, gastric cancer remains a major cause of death worldwide. In Canada alone, there are 2,800 new cases a year, a sobering 68% of which are fatal.

The results of gastrectomy have improved over the years with respect to postoperative mortality. But opinion has been divided on whether this improvement is partly due to the spread of extended lymph node dissection.

Dr Hartgrink and his team decided to address this question with a prospective randomized trial. They compared the morbidity, mortality, long-term survival and cumulative risk of relapse of a limited lymph node dissection to an extended lymph node dissection for gastric carcinoma.

A total of 711 patients with gastric adenocarcinoma were randomized to undergo limited or extended dissection.

Ten percent of patients in the 'extensive' group died within 30 days of the operation, compared to 4% of patients who underwent limited lymph node dissection. Similarly, morbidity associated with the surgery was higher among patients in the extended dissection group � 43% of patients compared to 25% in the limited dissection group.

Researchers concluded that any benefit from extended lymph node dissection was offset by the associated higher postoperative mortality. The authors suggest that extended lymph node dissection may only be of benefit when a physician is confident that morbidity and mortality can be minimized.

"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 [limited] lymphadenectomy, developing new agents for neoadjuvant and adjuvant clinical trials of gastric cancer and improving radiation techniques," suggested Dr Nicholas Petrelli, 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."