Consensus on peritoneal surgery
ESGO highlighted a new Lancet consensus—PSOGI–ESGO–ISSPP Lyon—laying out principles for cytoreductive surgery in primary and metastatic peritoneal malignancies (x.com). The society’s post linked to the Lancet abstract and presented the consolidated surgical recommendations for managing peritoneal disease types (x.com).
Cancer on the lining of the abdomen is often treated by stripping away visible tumor, and a new international consensus tries to standardize how surgeons do that operation. (thelancet.com) The paper, published in *The Lancet Oncology* on March 30, 2026, is the second part of the PSOGI–ESGO–ISSPP Lyon consensus and focuses on cytoreductive surgery for primary and metastatic peritoneal malignancies. (thelancet.com) Cytoreductive surgery means removing all visible cancer deposits from the peritoneum, the thin membrane that lines the abdominal cavity and covers many abdominal organs. The Lancet abstract says the key goal is “complete macroscopic resection,” meaning no tumor remains that the surgeon can see. (thelancet.com) The consensus says practice still varies across hospitals and between surgical oncology and gynecologic oncology teams, even when they are treating the same pattern of peritoneal disease. The document sets out common terminology for procedures, technical principles for peritonectomy and organ resections, and guidance on regional lymph nodes. (thelancet.com) That matters because peritoneal malignancy is not one disease. Johns Hopkins lists appendiceal, colorectal, gastric, pancreatic, ovarian, primary peritoneal cancer and peritoneal mesothelioma among the cancers that can spread across the abdominal lining and be considered for cytoreductive surgery, sometimes with heated chemotherapy delivered inside the abdomen. (hopkinsmedicine.org) The Lyon effort is also building in stages. A related paper in *BJS* on June 25, 2025 standardized the names and boundaries of peritonectomy procedures after two Delphi voting rounds involving 107 surgeons in round 1 and 101 in round 2, with consensus reached on 207 of 211 questions. (academic.oup.com) That earlier paper also shows the problem the new Lancet document is trying to solve: surgeons were using different names for the same operation, and the same name for operations that removed different amounts of tissue. The authors said they created a reporting form to document how much peritoneum was actually resected. (academic.oup.com) The groups behind the work span specialties that do not always publish together. The Peritoneal Surface Oncology Group International says it is a global collaboration focused on improving treatment and survival in peritoneal cancer through research, training and meetings, while the European Society of Gynaecological Oncology has been amplifying the consensus to its members. (psogi.com) The paper does not turn cytoreductive surgery into a routine operation for every patient with abdominal spread. It gives surgeons a shared playbook for a technically demanding procedure whose benefit depends heavily on tumor type, disease extent, and whether complete visible resection is feasible. (thelancet.com) For patients, the immediate change is mostly behind the scenes: a surgeon in a gynecologic cancer unit and a surgeon in a peritoneal surface malignancy program now have a new common language for describing what they plan to remove, what they removed, and what “complete” surgery means. (thelancet.com)
