Conduits in Vascular Pancreatic Surgery: Analysis of Clinical Outcomes, Operative Techniques, and Graft Performance

Distal Pancreatectomy: Extent of Resection Determines Surgical Risk Categories

BACKGROUND

Recently, subclassification of pancreatoduodenectomy in 4 differing types has been reported, because additional major vascular and multivisceral resections have been shown to be associated with an increased risk of postoperative morbidity and mortality.

OBJECTIVE

To classify distal pancreatectomy (DP) based on the extent of resection and technical difficulty and to evaluate postoperative outcomes with regards to this classification system.

METHODS

All consecutive patients who had undergone DP between 2001 and 2020 in a high-volume pancreatic surgery center were included in this study. DPs were subclassified into 4 distinct categories reflecting the extent of resection and technical difficulty, including standard DP (type 1), DP with venous (type 2), multivisceral (type 3), or arterial resection (type 4). Patient characteristics, perioperative data, and postoperative outcomes were analyzed and compared among the 4 groups.

RESULTS

A total of 2135 patients underwent DP. Standard DP was the most frequently performed procedure (64.8%). The overall 90-day mortality rate was 1.6%. Morbidity rates were higher in patients with additional vascular or multivisceral resections, and 90-day mortality gradually increased with the extent of resection from standard DP to DP with arterial resection (type 1: 0.7%; type 2: 1.3%; type 3: 3%; type 4: 8.7%; P <0.0001). Multivariable analysis confirmed the type of DP as an independent risk factor for 90-day mortality.

CONCLUSIONS

Postoperative outcomes after DP depend on the extent of resection and correlate with the type of DP. The implementation of the 4-type classification system allows standardized reporting of surgical outcomes after DP improving comparability of future studies.

Preoperative chemotherapy, radiotherapy and surgical decision-making in patients with borderline resectable and locally advanced pancreatic cancer

Surgical resection combined with systemic chemotherapy is the cornerstone of treatment for patients with localized pancreatic cancer. Upfront surgery is considered suboptimal in cases with extensive vascular involvement, which can be classified as either borderline resectable pancreatic cancer or locally advanced pancreatic cancer. In these patients, FOLFIRINOX or gemcitabine plus nab-paclitaxel chemotherapy is currently used as preoperative chemotherapy and is eventually combined with radiotherapy. Thus, more patients might reach 5-year overall survival. Patient selection for chemotherapy, radiotherapy and subsequent surgery is based on anatomical, biological and conditional parameters. Current guidelines and clinical practices vary considerably regarding preoperative chemotherapy and radiotherapy, response evaluation, and indications for surgery. In this Review, we provide an overview of the clinical evidence regarding disease staging, preoperative therapy, response evaluation and surgery in patients with borderline resectable pancreatic cancer or locally advanced pancreatic cancer. In addition, a clinical work-up is proposed based on the available evidence and guidelines. We identify knowledge gaps and outline a proposed research agenda.

Anatomical and Biological Considerations to Determine Resectability in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) remains associated with poor outcomes with a 5-year survival of 12% across all stages of the disease. These poor outcomes are driven by a delay in diagnosis and an early propensity for systemic dissemination of the disease. Recently, aggressive surgical approaches involving complex vascular resections and reconstructions have become more common, thus allowing more locally advanced tumors to be resected. Unfortunately, however, even after the completion of surgery and systemic therapy, approximately 40% of patients experience early recurrence of disease. To determine resectability, many institutions utilize anatomical staging systems based on the presence and extent of vascular involvement of major abdominal vessels around the pancreas. However, these classification systems are based on anatomical considerations only and do not factor in the burden of systemic disease. By integrating the biological criteria, we possibly could avoid futile resections often associated with significant morbidity. Especially patients with anatomically resectable disease who have a heavy burden of radiologically undetected systemic disease most likely do not derive a survival benefit from resection. On the contrary, we could offer complex resections to those who have locally advanced or oligometastatic disease but have favorable systemic biology and are most likely to benefit from resection. This review summarizes the current literature on defining anatomical and biological resectability in patients with pancreatic cancer.

Surgical Treatment of Pancreatic Cancer: Currently Debated Topics on Vascular Resection

Vascular resections involving the superior mesenteric and portal veins (SMV-PV), celiac axis (CA), superior mesenteric artery (SMA) and hepatic artery (HA) have multiplied in recent years, raising the resection rate for pancreatic cancer (PDAC) and the related morbidity and mortality rates. While resection is generally accepted for resectable SMV-PV, the usefulness of associated arterial resection in borderline resectable (BRPC) and locally-advanced PDAC (LAPC) is much debated. Careful selection of splenic vein reconstruction is very important to prevent left-sided portal hypertension (LSPH). During distal pancreatectomy (DP), CA and common HA resection is largely accepted, while there is debate on the value of SMA and proper HA resection and reconstruction. Their resection is useless according to several reviews and meta-analyses, and some international societies, although some high-volume centers have reported good results. Short- and long-term reconstructed vessel patency varies with the type of reconstruction, the material used, and the surgeon's experience. Laparoscopic and robotic pancreaticoduodenectomy and DP are generally accepted if done by surgeons performing at least 10 such procedures annually. The usefulness of associated vascular resection remains highly controversial. Surgeons need to complete numerous minimally-invasive procedures to overcome the learning curve, and prevent an increase in complications and surgical mortality. Higher resectability rates and satisfactory long-term results have been reported after neoadjuvant therapy (NAT) for BRPC and LAPC requiring vascular resection. It is essential to select the most appropriate NAT for a given patient and to assess PDAC resectability preoperatively.