Researchers at Amsterdam UMC have launched the OMEGA trial, an international, multicenter, randomized study investigating whether preserving the omentum—a fatty tissue layer covering abdominal organs—is non-inferior to complete omentum removal for patients undergoing gastric cancer surgery. Traditionally, omentum removal, which is standard practice during gastrectomy, is based on the belief that the omentum may harbor malignant cells. However, as the omentum also plays essential roles in immune defense and in preventing abdominal infections and adhesions, the question has been increasingly raised over the past decade: does its removal truly benefit patients?

The OMEGA trial builds on previous work by the Upper GI Surgery research team, which found that omental metastases are rare and only found in patients with advanced, incurable disease who face poor prognoses. Furthermore, other studies suggest that complete removal of the omentum can increase surgical risks. The procedure is associated with a higher risk of intraoperative complications, which can be particularly concerning during laparoscopic surgery. Patients may also be more vulnerable to intra-abdominal infections, which often have a severe clinical course. With support from the Esophageal and Gastric Cancer Fund (SLMK Fund), the OMEGA trial aims to determine whether omentum removal is truly necessary to improve survival outcomes.

The OMEGA trial will recruit 654 patients from Dutch and other European centers to compare outcomes between patients who undergo traditional omentum removal and those in whom the omentum is preserved. The randomized controlled trial design will allow the study to evaluate whether omentum preservation is non-inferior to complete omentectomy in terms of three-year overall survival rates. Additionally, the trial will assess secondary outcomes, including the rate of perioperative and long-term complications, quality of life, and cost-effectiveness, providing a comprehensive view of the impacts of omentum preservation versus removal.

Dr. Suzanne Gisbertz

Our previous studies laid the foundation for questioning the need for complete omentum removal in patients with gastric cancer. Every organ in the body has evolved with a purpose, and one of the fundamental principles in surgery is to be as sparing with tissue as possible. Through the OMEGA trial, we aim to provide conclusive evidence to guide more effective surgical decisions in patients with gastric cancer”.
Dr. Suzanne Gisbertz
Upper Gastrointestinal Surgeon at Amsterdam UMC, specialized in oesophageal and gastric cancer

Read more on the website [dutch]: OMEGA studie (Maagkanker) | Kanker.nl

Read the full publications:

People involved:

  • Dr. S.S. Gisbertz (Amsterdam UMC)
  • Prof. Dr. M.I. van Berge Henegouwen (Amsterdam UMC)
  • Dr. W.J. Eshuis (Amsterdam UMC)
  • Dr. S.L. Meijer (Amsterdam UMC)
  • Drs. K. Keywani (Amsterdam UMC)
  • Dr. B.I. Lissenberg-Witte (Vrije Universiteit Amsterdam)
  • Dr. M.J. van Det (Twente Hospital Group)
  • Dr. P. van Duijvendijk (Gelre Hospital)
  • Dr. B. van Etten (University Medical Center Groningen)
  • Dr. P.P. Grimminger (University Medical Center of the Johannes Gutenberg University)
  • Dr. J. Heisterkamp (Elisabeth Tweesteden Hospital)
  • Dr. P. van der Sluis (Erasmus Medical Center)
  • Dr. M.D.P. Luyer (Catharina Hospital)
  • Prof. Dr. S.R. Markar (University of Oxford)
  • Dr. J.P.E.N. Pierie (Medical Center Leeuwarden)
  • Prof. Dr. F. Roviello (University Hospital)
  • Prof. Dr. J.P. Ruurda (University Medical Center Utrecht)
  • Dr. J.W. van Sandick (The Netherlands Cancer Institute - Antoni van Leeuwenhoek)
  • Dr. M. Sosef (Zuyderland Hospital)
  • Dr. B.P.L. Witteman (Rijnstate Hospital)
  • Dr. W.O. de Steur (Leiden University Medical Center)

Funders involved
Esophageal and Gastric Cancer Fund (SLMK Fund)

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