Intraoperative Peritoneal Lavage for Detection of Malignant Cells: Technique, Evidence, Clinical Relevance and Future
Resa Puffert1, Anna Quarder1, Fabian Kockelmann1
1Department of General, Visceral and Transplant Surgery, Hannover Medical School, Carl-Neuberg-Straße 1, 30625 Hannover, Germany.
Background/Objectives:
Peritoneal metastases represent a common manifestation of advanced gastrointestinal malignancies and are associated with poor survival. Their early detection is essential for adequate tumor staging, prognosis, and treatment selection, especially to avoid unnecessary surgery. Intraoperative peritoneal lavage has been established as a diagnostic tool to detect occult peritoneal disease. However, reported techniques, analytical methods, and detection rates vary considerably. The objective of this review was to summarize current approaches to intraoperative peritoneal lavage, evaluate different detection methods, and assess their clinical relevance.
Methods:
A literature search was performed using the PubMed database for studies published between 2015 and 2025. The search terms "intraoperative peritoneal lavage" or "peritoneal fluid cytology" were used. Studies were included if they evaluated peritoneal lavage as a diagnostic method for detecting malignant cells, including all primary tumors and disease stages. Articles focusing on lavage as a therapeutic intervention or lacking methodological details were excluded.
Results:
Physiological saline solution was used for lavage in all included studies, with volumes ranging from 10 to 1000 mL. Sampling was predominantly performed immediately after abdominal access in various abdominal sites. Detection methods varied widely, with conventional cytology being most frequently used, while molecular techniques were used in a smaller number of studies. Positive detection rates showed broad variations and were higher in advanced tumor stages. Conventional cytology showed limited detection rates compared to molecular approaches.
Conclusions:
Intraoperative peritoneal lavage remains a valuable but methodologically heterogeneous diagnostic tool with limited detection rates when relying on conventional cytology alone. Molecular techniques seem to improve the detection rate of occult peritoneal disease but require further standardization and validation before routine clinical implementation. The technique of peritoneal lavage should be standardized by implementing an international consensus including lavage sites, volume of applied fluid, and detection method.
