Significance of staging laparoscopy in multidisciplinary treatment for pancreatic cancer: a narrative review

Background and Objective: Accurate evaluation of resectability classification before treatment initiation is particularly important in recent treatment strategies for pancreatic cancer. The problem is to consider which pancreatic cancer patients should be evaluated for gross and microscopic peritoneal dissemination by staging laparoscopy (SL) before treatment initiation. Methods: From January 2000 to December 2020, a literature about SL for pancreatic cancer search was performed using the PubMed database without language or geographic restriction to identify eligible studies. Titles and abstracts were screened to identify relevant articles, and evaluated for eligibility using predefined inclusion and exclusion criteria. Studies that mentioned peritoneal dissemination in reports examining the diagnostic performance of various therapies for distant metastases of pancreatic cancer were included. Articles were excluded if (I) they were not written in English, (II) relevant data could not be extracted, or (III) they were case reports, reviews, or letters to the editor. Key Content and Findings: Previous reports have been mixed in their diagnosis and definition of peritoneal seeding, including gross and histopathological diagnosis by SL and experimental laparotomy, diagnosis by ascites cytology, and imaging diagnosis with consideration of the clinical course. Indications for SL were limited except in cases that were candidates for surgical treatment, and the inability to microscopically assess for peritoneal seeding limited the diagnosis of peritoneal seeding in pancreatic cancer based on imaging alone. About diagnosis of pancreatic cancer with peritoneal dissemination by SL, 21% to 25% of patients diagnosed as resectable (R) by imaging were found to be unresectable (UR) by SL. On the other hand, 5–18% of patients who underwent SL had UR lesions diagnosed at laparotomy. Looking at microscopic and gross peritoneal dissemination diagnosed at SL by resectability, peritoneal dissemination tended to increase with progression, ranging from 2.2% to 23.8% in R, 12.1% to 28.6% in borderline resectable (BR), and 19.0% to 49.1% in unresectable locally advanced (UR-LA). In particular, more than half of UR-LA pancreatic cancers were cytology (CY) positive for peritoneal dissemination, suggesting that it is difficult to diagnose peritoneal dissemination by existing imaging alone. Conclusions: SL may contribute to more accurate pretreatment diagnosis, which in turn may lead to appropriate treatment based on early and appropriate resectability classification.