In recent years, minimally invasive distal pancreatectomy (MIDP) has gained popularity over open distal pancreatectomy (ODP) to treat resectable pancreatic cancer. However, doubts persist regarding the oncological safety of this technique. Recently published in Science, the results of the DIPLOMA study showed that MIDP is not inferior to ODP regarding radical resection rates. These findings support the inclusion of MIDP in guidelines as a standard, valid approach in patients with resectable pancreatic cancer.
Pancreatic cancer is currently the third most lethal cancer worldwide, with a five-year survival rate of 5-10%. For patients with resectable left-sided pancreatic cancer, the preferred treatment is distal pancreatectomy with splenectomy followed by adjuvant chemotherapy, with a five-year survival rate of approximately 20%. Traditionally, distal pancreatectomy was performed using an open approach (open distal pancreatectomy [ODP]). However, since its introduction in 1994, minimally invasive distal pancreatectomy (MIDP) has been gaining popularity. Although several studies have demonstrated the short-term benefits of MIDP over ODP in terms of functional recovery and hospital stay after treatment, concerns remain regarding the oncological safety of MIDP. To address these concerns, an international randomised trial was designed to investigate the oncological safety of MIDP as compared to ODP in patients with resectable pancreatic cancer in a non-inferior setup.
This study recruited adults with resectable pancreatic cancer from 35 centres in 12 countries. In total, 258 patients were randomly assigned (1:1) to either MIDP (laparoscopic or robotic, n=131) or open distal pancreatectomy (ODP, n=127). The primary endpoint was radical resection (R0), defined as the minimum margin of ≥1 mm between the tumour and surgical margin, measured at the transection and posterior margins in patients who underwent a resection. Analyses for the primary endpoint were conducted in the modified intention-to-treat population, excluding patients with missing data on the primary endpoint. This population included 114 patients in the MIDP group and 110 in the ODP group.
After a median follow-up of 23.5 months, the primary endpoint of R0 resection was achieved in 73% vs. 69% of patients who underwent MIDP and ODP, respectively. The absolute difference in the primary endpoint was 3.7% (90%CI: -6.2% to 13.6%), thus confirming the non-inferiority of MIDP compared to ODP (p-value for non-inferiority= 0.039). The median lymph node yield was comparable between the two groups (22.0 vs. 23.0 nodes in the MIDP and ODP, respectively, p= 0.86), as was the rate of intraperitoneal recurrence (41% vs. 38%, p= 0.45). Other postoperative outcomes were comparable, including median time to functional recovery (5 days each; p= 0.22) and overall survival (HR: 0.99, p= 0.94). Serious adverse events were reported in 18% vs. 22% of patients in the MIDP and ODP groups.
This trial provides evidence of the non-inferiority of MIDP compared to ODP regarding radical resection rates in patients with resectable pancreatic cancer. These findings underscore the safety and applicability of minimally invasive surgery for individuals with resectable left-sided pancreatic cancer.
Korrel M, Jones LR, van Hilst J, et al. Minimally invasive versus open distal pancreatectomy for resectable pancreatic cancer (DIPLOMA): an international randomised non-inferiority trial. Lancet Reg Health Eur. 2023;31:100673.