Minimally Invasive Pancreatic Enucleation With Main Pancreatic Duct Exposure, Repair or Reconstruction

Standard surgical procedures for benign or low-grade malignant pancreatic tumors is associated with increased risks of postoperative complications and long-term pancreatic functional impairment, while parenchyma-sparing pancreatectomy such as enucleation can reduce the incidence of complications and preserve healthy parenchyma, thereby preserve both endocrine and exocrine pancreatic function. It has been reported that pancreatic tumor enucleation is a safe and feasible approach in preserving normal physiological function in patients undergoing pancreatic surgery.

With the growing emphasis on routine screenings and the application of high-quality thin-slice imaging techniques, the detection rates of pancreatic tumors have witnessed a steady increase. Additionally, there is a notable trend towards younger patients being diagnosed with pancreatic tumors. Consequently, in conjunction with ensuring safe and thorough tumor resection while maximizing preservation of pancreatic function, there is a current clinical demand to further reduce surgical trauma.

Literature reviews and meta-analyses have demonstrated that minimally invasive enucleation procedures offer well-known advantages associated with minimally invasive approaches, such as shorter postoperative hospital stays and lower overall complication rates. While the occurrence rate of severe complications, such as postoperative hemorrhage, remains relatively low, the development of postoperative pancreatic fistula (POPF) continues to pose a challenging issue.

The distance between the tumor and the main pancreatic duct (MPD) is considered a crucial factor influencing the occurrence of POPF after enucleation. However, these data have been rarely described in previous studies, making it challenging to accurately assess their actual impact on the rate of POPF occurrence. Heeger et al. suggested that the risk of POPF increases with closer proximity of the tumor to the MPD. The incidence of POPF was higher in deep-seated tumors after pancreatic enucleation (distance to MPD <3 mm) compared to superficial tumors (>3 mm) (73.3% vs. 30.0%, P=0.002). Other studies have even limited this critical distance to 2mm. Some research has indicated that if the tumor invades or encases the MPD, enucleation surgery should be contraindicated, and standard resection should be preferred to avoid the risk of POPF postoperatively. However, a retrospective analysis by Strobel et al. on 166 cases of pancreatic tumor enucleation demonstrated that even tumors in close proximity to the MPD can be safely resected, although their study did not include cases with tumor encasement of the MPD.

During the expansive growth of solid tumors such as neuroendocrine tumors and solid pseudopapillary neoplasms, they can compress the MPD, causing inflammatory adhesions. Cystic tumors can also surround the MPD as they grow. Enucleation of these tumors may inevitably lead to exposure, injury, or transection of the MPD, necessitating repair and reconstruction. Recent years have seen successful cases reported of end-to-end anastomosis of the MPD. Minimally invasive techniques have also facilitated the promotion of MPD repair or bridging reconstruction surgeries. However, there remains a lack of comprehensive research data in this field.

The safety and feasibility of minimally invasive pancreatic tumor enucleation procedures involving MPD exposure, repair, or reconstruction, the control of POPF, and the long-term prognosis and quality of life of patients after MPD repair or reconstruction remain unclear. Therefore, this study aims to conduct a prospective cohort study. The results of this study will serve as a valuable reference for clinical practice and promote the development and application of minimally invasive pancreatic tumor enucleation procedures.

Inclusion criteria

• age between 18 and 75 years, regardless of gender;
• patients with solitary benign or low-grade malignant pancreatic tumors, including NET, SPN, and cystic tumors;
• eligible for pancreatic parenchyma-sparing resection (PSR) according to contemporary guidelines;
• patients with an ECOG performance status of 0 or 1;
• successfully received MIEN (laparoscopic or robotic)

Exclusion criteria

• body mass index > 35 kg/m2;
• concomitant malignancies;
• intraoperative frozen section or postoperative pathology indicating malignancy, requiring conversion to oncologic resection;
• loss to follow-up within 90 days postoperatively.