Spleen Preservation Versus Splenectomy in Left Pancreatectomy for Pancreatic Ductal Adenocarcinoma (SPLENDID)

Spleen Preservation Versus Splenectomy in Left Pancreatectomy for Pancreatic Ductal Adenocarcinoma (SPLENDID): an International Randomized Controlled Trial

Rationale: During left pancreatectomy for pancreatic ductal adenocarcinoma (PDAC), routine en-bloc splenectomy is performed to achieve complete nodal clearance of the splenic hilum. However, evidence that splenectomy improves survival is lacking, while splenectomy may increase postoperative morbidity and has lifelong consequences related to loss of splenic function. Spleen-preserving left pancreatectomy (SPLP) may be a safe alternative, but high-quality evidence is lacking.

Objective: To compare SPLP with left pancreatectomy with splenectomy (LPS) regarding overall survival and major postoperative morbidity in patients with resectable or borderline resectable PDAC.

Study design: An international, randomized, controlled, multicenter, non-inferiority trial.

Study population: Two groups of 180 patients (360 in total) with proven or suspected resectable or borderline resectable PDAC requiring left pancreatectomy.

Intervention: Spleen-preserving left pancreatectomy (SPLP)

Control: Left pancreatectomy with splenectomy (LPS)

Rationale: During left pancreatectomy for pancreatic ductal adenocarcinoma (PDAC), routine en-bloc splenectomy is performed to achieve complete nodal clearance of the splenic hilum. However, there is no evidence that routine splenectomy improves survival. Splenectomy has been associated with increased postoperative morbidity, lifelong vaccination requirements, and risk of overwhelming post-splenectomy infection. In addition, lymph node metastases in the splenic hilum are uncommon (~4%), and preservation of splenic immune function is becoming increasingly important with the emergence of novel immunotherapies. Spleen-preserving left pancreatectomy (SPLP) may therefore be a safe alternative to routine splenectomy, but no randomized trials have evaluated this approach.

Objective: To compare SPLP with left pancreatectomy with splenectomy (LPS) regarding (1) overall survival over a 3-year period, assessed using restricted mean survival time (RMST), and (2) major postoperative complications within 90 days (Clavien-Dindo grade III or higher) in patients with resectable or borderline resectable PDAC.

Study design: An international randomized multicenter non-inferiority trial performed in high-volume pancreatic centers. Participating centers perform at least 15 left pancreatectomies annually, and participating surgeons have completed at least 30 SPLPs (for any indication) and 15 left pancreatectomies for PDAC. Randomization will be performed in a 1:1 ratio using a secure web-based system, stratified for receipt of neoadjuvant therapy (yes/no) and tumor location (body/neck versus tail).

Study population: Two groups of 180 patients (360 in total) with proven or suspected resectable or borderline resectable PDAC requiring left pancreatectomy.

Intervention: Spleen-preserving left pancreatectomy.

Control: Left pancreatectomy with splenectomy.

Main study parameters/endpoints: The primary endpoint is overall survival over a 3-year period, assessed using RMST. The main secondary endpoint is major postoperative morbidity within 90 days (Clavien-Dindo grade III or higher). Other secondary outcomes include quality of life, R0 resection rate, disease-free survival, time to and site of recurrence, receipt, timing and completion of adjuvant therapy, pancreas-specific and general postoperative complications, unplanned splenectomy in the SPLP group, secondary splenectomy, spleen- and asplenia-related complications, time to functional recovery, length of hospital stay, health-care resource utilization, and cost-effectiveness.

Inclusion Criteria:

• Age at least 18 years;

• Elective indication for left pancreatectomy for proven or suspected PDAC;

• Upfront resectable or borderline-resectable PDAC in the pancreatic neck, body or tail, according to the National Comprehensive Cancer Network® (NCCN®);

  o Patients receiving neo-adjuvant treatment can be included in the trial, if the tumor was upfront resectable or borderline-resectable before the start of neoadjuvant therapy. Patients receiving induction therapy for locally advanced pancreatic cancer (LAPC) will be excluded.

• Spleen preservation using SPLP with the Warshaw (splenic vessel-resecting) procedure including Gerota's fascia (i.e. circumferentially radical) is feasible according to the local treatment team;

• Fit to undergo left pancreatectomy according to the surgeon and anesthesiologist;

• Written informed consent.

Exclusion Criteria:

• Preoperative imaging indicating (possible) tumor involvement of the perisplenic LNs (LN station 10 and perisplenic fat);
• Distance between the left border of the tumor and the center of the splenic hilum is <3cm on preoperative imaging;
• Locally advanced PDAC according to the NCCN definition or distant metastasis;
• Previous abdominal surgery in which the short gastric and/or left gastroepiploic vessels were ligated (e.g. gastrectomy, gastric sleeve, fundoplication), resulting in the impossibility of performing a Warshaw (spleen-vessel resecting) procedure;
• Pregnancy.