Systematic review and meta-analysis of contemporary pancreas surgery with arterial resection

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.

Surgical Planning for "Borderline Resectable" and "Locally Advanced" Pancreatic Cancer During Open Pancreatic Resection

Pancreatic resection for pancreatic ductal adenocarcinoma (PDAC) is one of the most complex procedures in abdominal surgery due to the technical and oncological challenges given by its local aggressive growth. The improvement of new multidrug chemotherapy regimens and surgical techniques has increased the caseload of "borderline resectable" (BR) or even "locally advanced" (LA) PDAC candidates for surgical resection. As a result, the increased heterogeneity of surgical scenarios has made it essential to utilize a tailored surgical strategy for each individual case. Notably, the strategy employed to approach and assess the peripancreatic vessels should be weighted according to tumor's location and the site of suspected vascular infiltration. The aim of this paper is to describe the open surgical approach for "BR" or "LA" PDAC used at our Institution and summarizes a "step-up approach" to manage vascular infiltration.

Assessment of the level III of Inoue by preoperative endoscopic ultrasound and elastography: a novel approach to predict a periarterial divestment technique in borderline resectable (BR) or locally advanced (LA) pancreatic adenocarcinoma-How I do it

BACKGROUND

Periarterial divestment is a surgical technique to approach borderline resectable (BR) or locally advanced (LA) pancreatic ductal adenocarcinoma (PDAC) with arterial involvement. There are no reports in the literature regarding the role of endoscopic ultrasound and elastography (EUS-EG) in exploring the integrity of Inoue's level III and its correlation with the periarterial divestment technique feasibility. Our research is aimed at exploring the role of EUS-EG in this scenario.

METHODS

We describe our approach to Inoue's level II by EUS-EG in patients with BR and LA pancreatic cancer patients after neoadjuvant chemotherapy.

RESULTS

Between June 2019 and December 2020, four patients out of 25 were eligible to perform a preoperative EUS-EG. In all cases, Inoue's level III integrity was corroborated by EUS-EG and confirmed posteriorly in the surgical scenario where a periarterial divestment technique was feasible. Vein resections were necessary in all cases, with no need for arterial resection. An R0 (> 1 mm) margin was achieved in all patients, and the histopathological assessment showed the presence of neurovascular tissue at the peripheral arterial margin.

CONCLUSION

Preoperatively, EUS-EG is a novel approach to explore the integrity of Inoue's level III and could be helpful to preclude a periarterial divestment technique in borderline resectable or locally advanced pancreatic adenocarcinoma with arterial involvement.

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

OBJECTIVES

We analyze successes and failures of pushing the boundaries in vascular pancreatic surgery to establish safety of conduit reconstructions.

BACKGROUND

Improved systemic control from chemotherapy in pancreatic cancer is increasing the demand for surgical solutions of extensive local vessel involvement, but conduit-specific data are scarce.

METHODS

We identified 63 implanted conduits (41% autologous vessels, 37% allografts, 18% PTFE) in 56 pancreatic resections of highly selected cancer patients between October 2013 and July 2020 from our prospectively maintained database. Assessed parameters were survival, perioperative complications, operative techniques (anatomic and extra-anatomic routes), and conduit patency.

RESULTS

For vascular reconstruction, 25 arterial and 38 venous conduits were utilized during 39 pancreatoduodenectomies, 14 distal pancreatectomies, and 3 total pancreatectomies. The median postoperative survival was 2 years. A Clavien-Dindo grade ≥IIIa complication was apparent in 50% of the patients with a median Comprehensive Complication Index of 29.6. The 90-day mortality in this highly selected cohort was 9%. Causes of mortality were conduit related in 3 patients, late postpancreatectomy hemorrhage in 1 patient, and early liver metastasis in 1 patient. Image-based patency rates of conduits were 66% and 45% at postoperative days 30 and 90, respectively.

CONCLUSIONS

Our perioperative mortality of vascular pancreatic surgery with conduits in the arterial or venous system is 9%. Reconstructions are technically feasible with different anatomic and extra-anatomic strategies, while identifying predictors of early conduit occlusion remains challenging. Optimizing reconstructed arterial and venous hemodynamics in the context of pancreatic malignancy will enable long-term survival in more patients responsive to chemotherapies.

Technical Implications for Surgical Resection in Locally Advanced Pancreatic Cancer

Pancreatic ductal adenocarcinoma remains a global health challenge and is predicted to soon become the second leading cause of cancer death in developed countries. Currently, surgical resection in combination with systemic chemotherapy offers the only chance of cure or long-term survival. However, only 20% of cases are diagnosed with anatomically resectable disease. Neoadjuvant treatment followed by highly complex surgical procedures has been studied over the last decade with promising short- and long-term results in patients with locally advanced pancreatic ductal adenocarcinoma (LAPC). In recent years, a wide variety of complex surgical techniques that involve extended pancreatectomies, including portomesenteric venous resection, arterial resection, or multi-organ resection, have emerged to optimize local control of the disease and improve postoperative outcomes. Although there are multiple surgical techniques described in the literature to improve outcomes in LAPC, the comprehensive view of these strategies remains underdeveloped. We aim to describe the preoperative surgical planning as well different surgical resections strategies in LAPC after neoadjuvant treatment in an integrated way for selected patients with no other potentially curative option other than surgery.

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.

Hepatic artery resection in distal cholangiocarcinoma

PURPOSE

This study aimed to elucidate the safety and oncological outcomes of surgery with hepatic artery resection (HAR) for patients with distal cholangiocarcinoma.

METHODS

The clinical data of patients with distal cholangiocarcinoma who underwent curative intent surgery at Hiroshima University between March 2009 and January 2021 were retrospectively analyzed. Eligible patients were classified according to the presence or absence of HAR (HAR and non-HAR group), and clinicopathological features and disease-free survival rates were compared between the two groups.

RESULTS

Among the 60 patients analyzed, eight patients had received HAR, and the remaining 52 patients had not. The rate of portal vein resection, T stage, and the number of metastasized lymph nodes in the HAR group were significantly greater than those in the non-HAR group (p < 0.001, p = 0.00695, and p = 0.0480, respectively). Postoperative severe complication was confirmed in one patient, and there were no in-hospital deaths in the HAR group. Seven of 8 patients in the HAR group showed recurrence during follow-up, and of those, six patients showed early recurrence within 1 year postoperatively. The disease-free survival time in the HAR group was significantly shorter than that in the non-HAR group (median: 7.4 m vs. 34.2 m, respectively) (p < 0.001). Multivariate analysis revealed that lymph node metastasis and HAR were significant risk factors for predicting the adverse disease-free survival time (hazard ratio (HR), 3.21; p = 0.0142; HR, 4.47; p = 0.0346, respectively).

CONCLUSIONS

Patients with distal cholangiocarcinoma who underwent surgery with HAR tended to show early recurrences, although HAR could be performed safely.

Pancreatectomy After Neoadjuvant FOLFIRINOX Chemotherapy: Identifying Factors Predicting Long-Term Survival

INTRODUCTION

We aimed to evaluate the long-term outcomes of the association of neoadjuvant chemotherapy with pancreatectomy with vascular resection in patients with locally advanced pancreatic cancer.

METHODS

Clinical data from patients who underwent pancreatic resection after neoadjuvant FOLFIRINOX were retrospectively reviewed. Cox analyses were used to identify factors prognostic of overall survival (OS).

RESULTS

FOLFIRINOX protocol was administered pre-operatively with a median number of nine cycles (range 2-18) in 98 patients. Types of resections included pancreaticoduodenectomy (n = 53), total pancreatectomy (n = 17), and distal spleno-pancreatectomy (n = 28). Venous resection and arterial resections were performed in 85 (86.7%) and 64 patients (65.3%), respectively. The overall 90-day mortality and morbidity rates were 6.1% (n = 6) and 47% (n = 47), respectively. The median OS was 31.08 months after surgery. OS rates at one, three, five, and 10 years were 82%, 47%, 28%, and 21%, respectively. According to the type of vascular resection, median OS and 5-year survival rates were exclusive venous resection (31.08 months; 23%) and arterial resections (24.7 months; 27%). Multivariate Cox analysis found lymph node involvement, venous invasion, and total pancreatectomy as independent prognostic factors for OS. According to the presence of 0 or 1-3 risk factors, 5-year survival (85% vs 16%) and median overall survival rates (not reached versus 24.7 months, respectively) were statistically significantly different (p < 0.0001).

CONCLUSIONS

A multimodal treatment, including neoadjuvant FOLFIRINOX combined with pancreatectomy with venous and arterial resection, achieves long term survival rates in patients with locally advanced disease. Surgery, in experienced centers, should be integrated into the treatment of patients with locally advanced pancreatic adenocarcinomas.

Validation of the ISGLS classification of bile leakage after pancreatic surgery: A rare but severe complication

INTRODUCTION

Hepaticoenterostomy is an important step of reconstruction during hepatopancreatobiliary (HPB) surgery with a subsequent bile leakage rate of up to 5%. The International Study Group of Liver Surgery (ISGLS) proposed a severity grading system for defining bile leakage after HPB surgery, which has not been validated after pancreatic surgery in a large patient cohort. The present study aimed to validate the ISGLS definition for bile leakage in pancreatic surgery and to investigate the postoperative outcomes of bile leakage after pancreatic resections.

MATERIALS AND METHODS

Data from the prospectively maintained database for pancreas surgery were extracted for any type of pancreatectomy with hepaticoenterostomy between 2006 and 2019. The severity of bile leakage was graded according to the ISGLS definition. The influence of our standardized hepaticoenterostomy technique and of the complexity of the surgical procedure on the rate of clinically relevant bile leakages (B and C) were assessed in three different timeframes.

RESULTS

Bile leakage was detected in 152 of 5,300 patients (2.9%). Clinically relevant bile leakages included seventy patients with grade B and eighty-two patients with grade C bile leakages (46.1% and 53.9%, respectively). During the study period, the overall rate of bile leakage showed to be stable (from 3.5% to 2.4%). Patients with grade C bile leakage had a higher rate of postoperative wound infection (P < 0.001) and longer ICU stays and hospital stays compared to patients with grade B bile leakage (P = 0.03 and P < 0.001 respectively). These parameters were significantly higher in patients with late grade C bile leakage but were similar between patients with grade B bile leakage and early grade C bile leakage (<5th day POD). In the whole patients' cohort, the 90-day mortality rate was 3.2% (174/5,300), with a rate of 25% in patients with bile leakage (38/152).

CONCLUSION

The ISGLS classification is a valid method for classifying postoperative bile leak after pancreas surgery. Standardization of our hepaticoenterostomy technique resulted in a stable rate of bile leakage. Although rare, bile leakage following pancreas surgery is a severe complication that has a major impact on patient outcomes and contributes significantly to morbidity and mortality, even in the absence of POPF.

[Better Therapy for Pancreatic Cancer through More Radical Surgery?]

Despite advances in the treatment of pancreatic cancer, the survival of affected patients remains limited. A more radical surgical therapy could help to improve the prognosis, in particular by reducing the local recurrence rate, which is around 45% in patients with resected pancreatic cancer. In addition, patients with oligometastatic pancreatic cancer could also benefit from a more radical indication for surgery.Based on an analysis of the literature, important principles of pancreatic cancer surgery were examined.Even if even more radical surgical approaches such as an "extended" lymphadenectomy or a standard complete pancreatectomy do not bring any survival advantage, complete resection of the tumour (R0), a thorough locoregional lymphadenectomy and an adequate radical dissection in the area of the peripancreatic vessels including periarterial nerve plexuses should be the standard of pancreatic carcinoma resections. Whenever necessary to achieve an R0 resection, resections of the pancreas have to be extended, as well as additional venous vascular resections and multivisceral resections had to be performed. Simultaneous arterial vascular resections as part of pancreatic resections as well as surgical resections in oligometastatic patients should, however, be reserved for selected patients. These aspects of the surgical technique in pancreatic carcinoma mentioned above must not be neglected from the point of view of an "existing limited prognosis". On the contrary, they form the absolutely necessary basis in order to achieve good survival results in combination with system therapy. However, it may always be necessary to adapt these standards according to the age, comorbidities and wishes of the patient.

Surgery for pancreatic cancer: current controversies and challenges

Two areas that remain the focus of improvement in pancreatic cancer include high post-operative morbidity and inability to uniformly translate surgical success into long-term survival. This narrative review addresses specific aspects of pancreatic cancer surgery, including neoadjuvant therapy, vascular resections, extended pancreatectomy, extent of lymphadenectomy and current status of minimally invasive surgery. R0 resection confers longer disease-free survival and overall survival. Vascular and adjacent organ resections should be undertaken after neoadjuvant therapy, only if R0 resection can be ensured based on high-quality preoperative imaging, and that too, with acceptable post-operative morbidity. Extended lymphadenectomy does not offer any advantage over standard lymphadenectomy. Although minimally invasive distal pancreatectomies offers some short-term benefits over open distal pancreatectomy, safety remains a concern with minimally invasive pancreatoduodenectomy. Strict adherence to principles and judicious utilization of surgery within a multimodality framework is the way forward.

Curing pancreatic cancer

The distinct biology of pancreatic cancer with aggressive and early invasive tumor cells, a tumor promoting microenvironment, late diagnosis, and high therapy resistance poses major challenges on clinicians, researchers, and patients. In current clinical practice, a curative approach for pancreatic cancer can only be offered to a minority of patients and even for those patients, the long-term outcome is grim. This bitter combination will eventually let pancreatic cancer rise to the second leading cause of cancer-related mortalities. With surgery being the only curative option, complete tumor resection still remains the center of pancreatic cancer treatment. In recent years, new developments in neoadjuvant and adjuvant treatment have emerged. Together with improved perioperative care including complication management, an increasing number of patients have become eligible for tumor resection. Basic research aims to further increase these numbers by new methods of early detection, better tumor modelling and personalized treatment options. This review aims to summarize the current knowledge on clinical and biologic features, surgical and non-surgical treatment options, and the improved collaboration of clinicians and basic researchers in pancreatic cancer that will hopefully result in more successful ways of curing pancreatic cancer.

Technical advances in surgery for pancreatic cancer

BACKGROUND

Multimodal treatment concepts enhance options for surgery in locally advanced pancreatic ductal adenocarcinoma (PDAC). This review provides an overview of technical advances to facilitate curative-intent resection in PDAC.

METHODS

A review of the literature addressing current technical advances in surgery for PDAC was performed, and current state-of-the-art surgical techniques summarized.

RESULTS

Artery-first and uncinate-first approaches, dissection of the anatomical triangle between the coeliac and superior mesenteric arteries and the portomesenteric vein, and radical antegrade modular pancreatosplenectomy were introduced to enhance the completeness of resection and reduce the risk of local recurrence. Elaborated techniques for resection and reconstruction of the mesenteric-portal vein axis and a venous bypass graft-first approach frequently allow resection of PDAC with venous involvement, even in patients with portal venous congestion and cavernous transformation. Arterial involvement does not preclude surgical resection per se, but may become surgically manageable with recent techniques of arterial divestment or arterial resection following neoadjuvant treatment.

CONCLUSION

Advanced techniques of surgical resection and vessel reconstruction provide a toolkit for curative-intent surgery in borderline resectable and locally advanced PDAC. Effects of these surgical approaches on overall survival remain to be proven with high-level clinical evidence.

Distal Pancreatectomy with Celiac Axis Resection: Systematic Review and Meta-Analysis

Simple Summary

The literature is conflicting regarding the feasibility and survival outcomes of distal pancreatectomy with celiac axis resection (DP-CAR), although this procedure, in selected cases, represents the only therapeutical option for patients with locally advanced pancreatic cancer. The available studies often include small surgical populations, and there are important variations in the inclusion criteria and pre- and post-operative treatment. The purpose of this study was to provide an overview of the literature of the last 15 years, to evaluate the efficacy and the clinical safety of this procedure. This could help physicians in the choice of a multidisciplinary targeted therapeutical plan for patients. The combination of neoadjuvant chemo/radiochemotherapy and demolitive surgeries such as DP-CAR could have a role in changing the survival outcomes of patients with locally advanced pancreatic adenocarcinoma.

Abstract

Background: Major vascular invasion represents one of the most frequent reasons to consider pancreatic adenocarcinomas unresectable, although in the last decades, demolitive surgeries such as distal pancreatectomy with celiac axis resection (DP-CAR) have become a therapeutical option. Methods: A meta-analysis of studies comparing DP-CAR and standard DP in patients with pancreatic adenocarcinoma was conducted. Moreover, a systematic review of studies analyzing oncological, postoperative and survival outcomes of DP-CAR was conducted. Results: Twenty-four articles were selected for the systematic review, whereas eleven were selected for the meta-analysis, for a total of 1077 patients. Survival outcomes between the two groups were similar in terms of 1 year overall survival (OS) (odds ratio (OR) 0.67, 95% confidence interval (CI) 0.34 to 1.31, p = 0.24). Patients who received DP-CAR were more likely to have T4 tumors (OR 28.45, 95% CI 10.46 to 77.37, p < 0.00001) and positive margins (R+) (OR 2.28, 95% CI 1.24 to 4.17, p = 0.008). Overall complications (OR, 1.72, 95% CI, 1.15 to 2.58, p = 0.008) were more frequent in the DP-CAR group, whereas rates of pancreatic fistula (OR 1.16, 95% CI 0.81 to 1.65, p = 0.41) were similar. Conclusions: DP-CAR was not associated with higher mortality compared to standard DP; however, overall morbidity was higher. Celiac axis involvement should no longer be considered a strict contraindication to surgery in patients with locally advanced pancreatic adenocarcinoma. Considering the different baseline tumor characteristics, DP-CAR may need to be compared with palliative therapies instead of standard DP.

Radical Resection for Locally Advanced Pancreatic Cancers in the Era of New Neoadjuvant Therapy-Arterial Resection, Arterial Divestment and Total Pancreatectomy

Simple Summary

Aggressive arterial resection or total pancreatectomy in surgical treatment for locally advanced pancreatic cancer (LAPC) has gradually been encouraged thanks to new chemotherapy regimens such as FOLFIRINOX or Gemcitabine and nab-paclitaxel, which have provided more adequate patient selection and local tumor suppression, justifying aggressive local resection. The development of surgical techniques provides the safety of arterial resection (AR) for even major visceral arteries, such as the celiac axis or superior mesenteric artery. Total pancreatectomy has been re-evaluated as an effective option to balance both the local control and postoperative safety. In this review, we investigate the recent reports focusing on arterial resection and total pancreatectomy for locally advanced pancreatic cancer (LAPC) and discuss the rationale of such an aggressive approach in the treatment of PC.

Abstract

Aggressive arterial resection (AR) or total pancreatectomy (TP) in surgical treatment for locally advanced pancreatic cancer (LAPC) had long been discouraged because of their high mortality rate and unsatisfactory long-term outcomes. Recently, new chemotherapy regimens such as FOLFIRINOX or Gemcitabine and nab-paclitaxel have provided more adequate patient selection and local tumor suppression, justifying aggressive local resection. In this review, we investigate the recent reports focusing on arterial resection and total pancreatectomy for LAPC and discuss the rationale of such an aggressive approach in the treatment of PC. AR for LAPCs is divided into three, according to the target vessel. The hepatic artery resection is the simplest one, and the reconstruction methods comprise end-to-end, graft or transposition, and no reconstruction. Celiac axis resection is mainly done with distal pancreatectomy, which allows collateral arterial supply to the liver via the pancreas head. Resection of the superior mesenteric artery is increasingly reported, though its rationale is still controversial. Total pancreatectomy has been re-evaluated as an effective option to balance both the local control and postoperative safety. In conclusion, more and more aggressive pancreatectomy has become justified by the principle of total neoadjuvant therapy. Further technical standardization and optimal neoadjuvant strategy are mandatory for the global dissemination of aggressive pancreatectomies.