Appraisal of a total meso-pancreatoduodenum excision with pancreaticoduodenectomy for pancreatic head carcinoma

Morphology of the Dorsal Pancreatic Artery and Its Oncological Significance in Pancreatic Cancer

OBJECTIVES

Although the dorsal pancreatic artery (DPA) is an important artery that supplies the pancreas, its morphology has not been sufficiently studied. We investigated the morphology of the DPA and the progression of pancreatic cancer along this vessel.

MATERIALS AND METHODS

Overall, 142 patients with pancreatic cancer who underwent surgical resection at Kanazawa University Hospital between 2004 and 2015 were enrolled. We examined the morphology of the DPA using preoperative computed tomography and cancer progression along the DPA using resected specimens. We investigated the anatomical structures surrounding the DPA through cadaveric examination.

RESULTS

The analysis of computed tomography images revealed the presence of the DPA in 141 patients. In typical cases, the DPA divides into a head and a body branch. Histopathological examination revealed cancer progression along the DPA in 32 patients. Cancer progression along the DPA was identified as a factor associated with a poor prognosis in pancreatic head or body cancer. Cadaveric examination showed the presence of abundant nerve and lymphatic tissues along the DPA.

CONCLUSIONS

It is important to remove the soft tissue surrounding the DPA during surgery for pancreatic head or body cancer because it may serve as an important route for cancer progression.

Levels of Robotic Mesopancreas Dissection According to Malignancy and Vascular Anatomy: What Surgeons Need to Know

INTRODUCTION

The robotic approach is attracting increasing interest among the surgical community, and more and more series describing robotic pancreatoduodenectomy have been reported. Thus, surgeons performing robotic pancreatoduodenectomy should be confident with this critical step's potential scenarios.

MATERIALS AND METHODS

According to Yosuke et al., there are three different levels of mesopancreas dissection. We describe the main steps for a safe mesopancreas dissection by robotic approach.

RESULTS

This multimedia article provides, for the first time in literature, a comprehensive step-by-step overview of the mesopancreas dissection during robotic pancreatoduodenectomy (PD) and its three different levels according to tumor type.

CONCLUSIONS

Through the tips and indications presented in this multimedia article, we aim to familiarize surgeons with the mesopancreas dissections levels according to type of malignancy and vascular anatomy.

Laparoscopic pancreaticoduodenectomy with portal or superior mesenteric vein resection and reconstruction for pancreatic cancer: A single-center experience

BACKGROUND

Open pancreaticoduodenectomy (OPD) with portal or superior mesenteric vein resection and reconstruction has been applied in pancreatic cancer patients with tumor infiltration or adherence. However, it is controversial whether laparoscopic pancreaticoduodenectomy (LPD) with major vascular resection and reconstruction is feasible. This study aimed to evaluate the safety and feasibility of LPD with major vascular resection compared with OPD with major vascular resection.

METHODS

We reviewed data for all pancreatic cancer patients undergoing LPD or OPD with vascular resection at Department of Pancreatic Surgery, Fudan University Shanghai Cancer Center, between February 2018 and May 2022. We compared the preoperative, intraoperative, and postoperative clinicopathological data of the two groups to conduct a comprehensive evaluation of LPD with major vascular resection.

RESULTS

A total of 63 patients underwent pancreaticoduodenectomy (PD) with portal or superior mesenteric vein resection and reconstruction, including 25 LPDs and 38 OPDs. The LPD group had less intraoperative blood loss (200 vs. 400 mL, P < 0.001), lower proportion of intraoperative blood transfusion (16.0% vs. 39.5%, P = 0.047), longer operation time (390 vs. 334 min, P = 0.004) and shorter postoperative hospital stay (11 vs. 14 days, P = 0.005). There was no perioperative death in all patients. There was no significant difference in the incidence of total postoperative complications, grade B/C postoperative pancreatic fistula, delayed gastric emptying and abdominal infection between the two groups. No postpancreatectomy hemorrhage nor bile leakage occurred during perioperative period. There was no significant difference in R0 resection rate and number of lymph nodes harvested between the two groups. Patency of reconstructed vessels in the two groups were 96.0% and 92.1%, respectively (P = 0.927).

CONCLUSIONS

LPD with portal or superior mesenteric vein resection and reconstruction was safe, feasible and oncologically acceptable for selected patients with pancreatic cancer, and it can achieve similar or even better perioperative results compared to open approach.

First jejunal vein, jejunal trunk, and pancreatico-duodenectomy: resolving the literature conundrum

A detailed knowledge of the surgical anatomy of tributaries of the superior mesenteric vein, especially proximal jejunal venous anatomy (first jejunal vein and jejunal trunk), is a key prerequisite for performing a safe pancreatico-duodenectomy. However, the available literature on the anatomical course and surgical relevance of these vessels is scarce, the nomenclature across the articles is heterogeneous, and the resulting evidence is confusing to interpret. Standardized terminology and an in-depth review of these vessels with regard to their course, termination, vascular relations, and variations will help the surgeons in planning and performing this complex surgery safely, especially when a venous resection and reconstruction is planned in cases of borderline resectable pancreatic cancer. A uniform nomenclature and a unifying classification are proposed in this review for these two tributaries to help resolve the literature conundrum. This standardized terminology and anatomical description will assist the radiologists in reporting pancreatic protocol-computed tomography scans and surgeons in selecting the appropriate steps for the different anatomical orientations of these tributaries for the performance of safe pancreatic surgery. This will also help future researchers communicate in well-defined terms in reference to these tributaries so as to avoid confusion in future studies.

Location, Location, Location: What Should be Targeted Beyond Gross Disease for Localized Pancreatic Ductal Adenocarcinoma? Proposal of a Standardized Clinical Tumor Volume for Pancreatic Ductal Adenocarcinoma of the Head: The "Triangle Volume"

PURPOSE

In patients with borderline resectable or locally advanced pancreatic adenocarcinoma (BRPC/LAPC), local failure rates after resection remain significant, even in the setting of neoadjuvant chemotherapy and radiation. Suboptimal local control may relate to variable radiation target delineation, as no consensus exists around clinical tumor volume (CTV) design in this context. In the surgical literature, recent attention has been given to the "triangle" volume (TV) as a source of subclinical, residual disease. To understand whether the TV can inform optimal CTV design, we mapped locoregional failures after resection in a large cohort of patients with BRPC/LAPC and compared locations of failure to the TV.

METHODS AND MATERIALS

Patients with BRPC/LAPC of the head or neck diagnosed between 2016 AND 2019 who developed locoregional failure after surgery, neoadjuvant chemotherapy, and radiation were identified. Descriptive statistics were generated to report the frequency of locoregional failures located within the TV and the frequency of new vascular involvement at time of failure, compared with vascular involvement at diagnosis. Additionally, dosimetric coverage of the TV with the preoperative radiation plan that had been used was assessed.

RESULTS

In 31 patients who experienced locoregional failure, the centroid of failure was located within the TV in 28 cases (90%). Extent of vascular involvement at time of locoregional failure included vasculature that had not been involved at diagnosis in 13 cases (42%). The preoperative radiation plan that had been used provided a median V33 Gy and V25 Gy of the TV of only 53% (interquartile range, 34%-72%) and 70% (IQR, 48%-85%), respectively.

CONCLUSIONS

The TV encompassed the vast majority of locoregional failures, but dosimetric coverage of the TV was poor when only targeting gross disease and the full circumference of involved vasculature. As such, the TV may better serve as a basis for CTV design in patients with BRPC/LAPC undergoing neoadjuvant radiation.

Korean Surgical Practice Guideline for Pancreatic Cancer 2021: A summary of evidence-based surgical approaches

Pancreatic cancer is the eighth most common cancer and the fifth most common cause of cancer-related deaths in Korea. Despite the increasing incidence and high mortality rate of pancreatic cancer, there are no appropriate surgical practice guidelines for the current domestic medical situation. To enable standardization of management and facilitate improvements in surgical outcome, a total of 10 pancreatic surgical experts who are members of Korean Association of Hepato-Biliary-Pancreatic Surgery have developed new recommendations that integrate the most up-to-date, evidence-based research findings and expert opinions. This is an English version of the Korean Surgical Practice Guideline for Pancreatic Cancer 2021. This guideline includes 13 surgical questions and 15 statements. Due to the lack of high-level evidence, strong recommendation is almost impossible. However, we believe that this guideline will help surgeons understand the current status of evidence and suggest what to investigate further to establish more solid recommendations in the future.

Neoadjuvant Treatment Lowers the Risk of Mesopancreatic Fat Infiltration and Local Recurrence in Patients with Pancreatic Cancer

Simple Summary

After the implementation of an in-depth histopathological pancreas protocol, curative resection rates for pancreatic head cancers have drastically dropped. Standardized extended resections using embryo-anatomic landmarks (MPE), have recently been prooved to increase margin-negative resection rates. The mesopancreatic fat, excised during these extended resections, was infiltrated in the majority of the patients. Neoadjuvant treatment is an emerging topic of interest for pancreatic cancer patients. It remains unclear if these extended resections are still warranted in patients after neoadjuvant treatment. Neoadjuvant treatment lowered the risk for mesopancreatic fat infiltration and patients were less prone to local recurrence and margin positive resections when compared to patients after upfront surgery. However, the majority of the patients are yet diagnosed with mesopancreatic fat infiltration, justifying this extended approach synergistically with the treatment strategies for colorectal cancer.

Abstract

Background: Survival following surgical treatment of ductal adenocarcinoma of the pancreas (PDAC) remains poor. The recent implementation of the circumferential resection margin (CRM) into standard histopathological evaluation lead to a significant reduction in R0 rates. Mesopancreatic fat infiltration is present in ~80% of PDAC patients at the time of primary surgery and recently, mesopancreatic excision (MPE) was correlated to complete resection. To attain an even higher rate of R0(CRM−) resections in the future, neoadjuvant therapy in patients with a progressive disease seems a promising tool. We analyzed radiographic and histopathological treatment response and mesopancreatic tumor infiltration in patients who received neoadjuvant therapy prior to MPE. The aim of our study was to evaluate the need for MPE following neoadjuvant therapy and if multi-detector computed tomographically (MDCT) evaluated treatment response correlates with mesopancreatic (MP) infiltration. Method: Radiographic, clinicopathological and survival parameters of 27 consecutive patients who underwent neoadjuvant therapy prior to MPE were evaluated. The mesopancreatic fat tissue was histopathologically analyzed and the 1 mm-rule (CRM) was applied. Results: In the study collective, both the rate of R0 resection R0(CRM−) and the rate of mesopancreatic fat infiltration was 62.9%. Patients with MP infiltration showed a lower tumor response. Surgical resection status was dependent on MP infiltration and tumor response status. Patients with MDCT-predicted tumor response were less prone to MP infiltration. When compared to patients after upfront surgery, MP infiltration and local recurrence rate was significantly lower after neoadjuvant treatment. Conclusion: MPE remains warranted after neoadjuvant therapy. Mesopancreatic fat invasion was still evident in the majority of our patients following neoadjuvant treatment. MDCT-predicted tumor response did not exclude mesopancreatic fat infiltration.

Application and progress of medical imaging in total mesopancreas excision for pancreatic head carcinoma

Pancreatic head carcinoma (PHC) is one of the common gastrointestinal malignancies with a high morbidity and poor prognosis. At present, radical surgery is still the curative treatment for PHC. However, in clinical practice, the actual R0 resection rate, the local recurrence rate, and the prognosis of PHC are unsatisfactory. Therefore, the concept of total mesopancreas excision (TMpE) is proposed to achieve R0 resection. Although there have various controversies and discussions on the definition, the range of excision, and clinical prognosis of TMpE, the concept of TMpE can effectively increase the R0 resection rate, reduce the local recurrence rate, and improve the prognosis of PHC. Imaging is of importance in preoperative examination for PHC; however, traditional imaging assessment of PHC does not focus on mesopancreas. This review discusses the application of medical imaging in TMpE for PHC, to provide more accurate preoperative evaluation, range of excision, and more valuable postoperative follow-up evaluation for TMpE through imaging. It is believed that with further extensive research and exploratory application of TMpE for PHC, large-sample and multicenter studies will be realized, thus providing reliable evidence for imaging evaluation.

Anatomical Study of the Duodenojejunal Uncinate Process Vein: A Key Landmark for Mesopancreatoduodenal Resection During Pancreaticoduodenectomy

Background

The mesopancreas or mesopancreatoduodenum is an important anatomical concept during pancreaticoduodenectomy (PD) in patients with periampullary carcinoma. This study investigated whether the duodenojejunal uncinate process vein (DJUV), which is defined as the vein draining from the upper jejunum to the superior mesenteric vein adjacent to the uncinate process, is a useful anatomical landmark for the caudal border of mesopancreatoduodenum resection during PD.

Methods

This study enrolled 100 adult patients with hepatobiliary pancreatic disease who underwent preoperative multidetector‐computed tomography (CT). The anatomy of the key blood vessels involved during PD, and the relationship between these vessels and the DJUV, were analyzed by preoperative CT.

Results

The first jejunal vein was the DJUV in 85 cases, whereas the second jejunal vein was the DJUV in 15 cases. Furthermore, the DJUV was classified into two subtypes depending on its positional relationship with the superior mesenteric artery (SMA). The inferior pancreaticoduodenal artery and vein were located on the cranial side of the DJUV in all cases. The distance between the middle colonic artery, used as a guide for regional lymph nodes, and the point where the DJUV intersected the SMA was within 10 mm in 80% of cases. These results imply that using the DJUV as a landmark for the caudal border of the mesopancreatoduodenum provides a safe approach and enables sufficient dissection of regional lymph nodes and tissues around the SMA.

Conclusion

The DJUV may be a useful anatomical landmark for the caudal border of the mesopancreatoduodenum resection during PD.

The role of mesopancreas excision for ampullary carcinomas: a single center propensity-score matched analysis

BACKGROUND

Few evidences are available on the prognostic role of mesopancreas excision(MPe) for ampullary cancers(ACs). Aim of this study was to compare the long-term outcomes between pancreaticoduodenectomy(PD) with(PD-MPe group) and without(sPD group) MP.

METHODS

Thirty-seven sPDs were matched and compared to 37 PD-MPes for perioperative outcomes, recurrence rate, disease-free(DFS) and overall survival(OS).

RESULTS

The PD-MPe technique related to a significantly higher number of harvested lymph nodes[16 (±6)] as compared to the sPD [10 (±5); p < 0.0001]. Tumor recurrence was more frequent in the sPD cohort[21 (56.8%) vs 12 (32.4%) in the PD-MPe population; p = 0.03]. Although not statistically different, PD-MPe was associated with a better DFS(40% vs 35.7% for sPD; p = 0.08) and OS(59.3% vs 39.1% for sPD; p = 0.07). At the multivariate analysis, a higher number of lymph nodes retrieved and a more extensive lymphovascular clearance reached with the MPe technique, together with lymph nodes metastases, were recognized as independent prognostic factors for a worse OS and DFS.

CONCLUSION

The PD-MPe technique is associated with a better oncological radicality thanks to the higher number of retrieved lymph nodes and to the more appropriate tumor clearance. This reflects in a lower incidence of tumor relapse and in improved outcomes in terms of OS and DFS.

Paraaortic dissection in "total mesopancreas excision" and "mesopancreas-first resection" pancreaticoduodenectomies for pancreatic cancer: Useless, optional, or necessary?A systematic review

The mesopancreas does not have well-defined boundaries but is continuous and connected through its components with the paraaortic area. The mesopancreatic resection margin has been indicated as the primary site for R1 resection after PD in pancreatic head cancer and total mesopancreas excision has been proposed to achieve adequate retropancreatic margin clearance and to minimize the likelihood of R1 resection. However, the anatomy of the mesopancreas requires extended dissection of the paraaortic area to maximize posterior clearance. The artery-first surgical approach has been developed to increase local radicality at the mesopancreatic resection margin. During PD, the artery-first approach begins with dissection of the connective tissues around the SMA. However, the concept of the mesopancreas as a boundless structure that includes circumferential tissues around the SMA, SMV, and paraaortic tissue highlights the need to shift from artery-first PD to mesopancreas-first PD to reduce the risk of R1 resection. From this perspective the "artery-first" approach, which allows for the avoidance of R2 resection risk, should be integrated into the "mesopancreas-first" approach to improve the R0 resection rate. In total mesopancreas excision and mesopancreas-first pancreaticoduodenectomies, the inclusion of the paraaortic area and circumferential area around the SMA in the resection field is necessary to control the tumour spread along the mesopancreatic resection margin rather than to control or stage the spread in the nodal basin.

What do surgeons need to know about the mesopancreas

BACKGROUND

Pancreatoduodenectomy is the only treatment with a promise of cure for patients with pancreatic head adenocarcinoma, and a negative resection margin is an important factor related to overall survival. Complete clearance of the medial margin with removal of the so-called mesopancreas may decrease the recurrence rate after pancreatic resection. Here, we present some important information about the mesopancreas, total mesopancreas excision, and technical aspects to achieve negative resection margins. The area named mesopancreas is defined as the tissue located between the head of the pancreas and the superior mesenteric vessels and the celiac axis and consists of the nerve plexus, lymphatic tissue, and connective tissue. The superior mesenteric and celiac arteries define the border of the mesopancreas. En bloc resection of anterior and posterior pancreatoduodenal nodes, hepatoduodenal nodes, along the superior mesenteric artery nodes, pyloric nodes, and nodes along the common hepatic artery is necessary.

CONCLUSIONS

Improved knowledge of the surgical anatomy of the region and technical refinements of excision of the mesopancreas along with standardized pathological examination are important to increase and to determine radical resection of pancreatic head cancer.

Complete circumferential lymphadenectomy around the superior mesenteric artery with preservation of nerve plexus reduces locoregional recurrence after pancreatoduodenectomy for resectable pancreatic ductal adenocarcinoma

BACKGROUND

Evaluation of recurrence pattern and risk factors for recurrence are essential for good rates of survival after upfront pancreatoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC).

METHODS

This retrospective study included 167 consecutive patients who underwent upfront PD for resectable PDAC between 2000 and 2018. Postoperative recurrences were classified into three patterns according to initial recurrence site: isolated locoregional, isolated distant, and simultaneous locoregional and distant recurrences.

RESULTS

This study found 114 patients who developed postoperative recurrence (68.3%), including 37 patients with isolated locoregional recurrence (32.5%), 67 patients with isolated distant recurrence (58.8%), and 10 patients with simultaneous locoregional and distant recurrences (6.0%). When locoregional recurrence was classified based on the location of recurrent lesions, locoregional recurrence most commonly occurred around the superior mesenteric artery (SMA) (70.2%), followed by around the hepatic artery (25.5%) and in the paraaortic region (14.9%). Multivariate analyses showed that complete circumferential lymphadenectomy around the SMA, including not only the right side, but also the left side, was an independent factor for reduction of locoregional recurrence (P = 0.019, odds ratio [OR]: 2.217). Lymph node metastasis was an independent risk factor for both locoregional (P < 0.001, OR: 3.686) and distant recurrences (P < 0.001, OR: 4.315). Non-completion of postoperative adjuvant therapy was a risk factor for distant recurrence (P < 0.001, OR: 3.748).

CONCLUSION

Based on our data, complete circumferential lymphadenectomy around the SMA might contribute to local control, and multidisciplinary treatment including neoadjuvant therapy might be needed for resectable PDAC with high risk for recurrence.

Survival in resectable pancreatic ductal adenocarcinoma with para-aortic lymph node dissection: A retrospective study in Vietnamese population

Background

Pancreatic ductal adenocarcinoma (PDAC) has a high recurrence rate and poor outcome. Lymph node (LN) metastasis, especially para-aortic LN (PALN), is an important prognostic factor. PALN assessment through sampling with frozen-section analysis is a validated method. Our aim was to evaluate the prognostic impact of PALN on overall survival (OS) in patients who underwent standard pancreaticoduodenectomy, lymphadenectomy with PALN sampling, as well as to identify other prognostic factors for survival.

Methods

Our retrospective study included 89 PDAC patients undergoing radical resection with PALN sampling. The patients were classified into PALN(+) (n = 11) and PALN(-) (n = 78). Univariate and multivariate analyses of 1-year and 3-year OS and Kaplan-Meier model were used.

Results

OS after 1-year for PALN(+) and PALN(-) was 18.2 and 56.4%, after 3-year was 15.4% and 0%, respectively. Tumor differentiation, LN metastasis (LN(-), LN(+) PALN(-), LN(+) PALN(+)) were significant prognostic factors in both univariate and multivariate analyses for 1-year OS, and neural invasion (PN) was the solely significant factor for 3-year OS (p < 0.05). Kaplan-Meier estimate showed that OS of PALN(+) and PN (+) was significantly lower than the negative group, respectively (p < 0.05). No statistical difference in OS was seen between LN(-) and LN(+) PALN(-); and between LN(+) PALN(-) and PALN(+) (p = 0.107). Patients with PN (-) PALN(+) had similar OS compared to PN (+) PALN(-) (p > 0.05).

Conclusion

PDAC had a poor outcome despite treatment with radical resection. Further follow-up should be conducted to determine the role of surgery in PALN(+)and PN invasion.

Predictive factors for long-term survival after surgery for pancreatic ductal adenocarcinoma: Making a case for standardized reporting of the resection margin using certified cancer center data

Factors for overall survival after pancreatic ductal adenocarcinoma (PDAC) seem to be nodal status, chemotherapy administration, UICC staging, and resection margin. However, there is no consensus on the definition for tumor free resection margin. Therefore, univariate OS as well as multivariate long-term survival using cancer center data was analyzed with regards to two different resection margin definitions. Ninety-five patients met inclusion criteria (pancreatic head PDAC, R0/R1, no 30 days mortality). OS was analyzed in univariate analysis with respect to R-status, CRM (circumferential resection margin; positive: ≤1mm; negative: >1mm), nodal status, and chemotherapy administration. Long-term survival >36 months was modelled using multivariate logistic regression instead of Cox regression because the distribution function of the dependent data violated the requirements for the application of this test. Significant differences in OS were found regarding the R status (Median OS and 95%CI for R0: 29.8 months, 22.3–37.4; R1: 15.9 months, 9.2–22.7; p = 0.005), nodal status (pN0 = 34.7, 10.4–59.0; pN1 = 17.1, 11.5–22.8; p = 0.003), and chemotherapy (with CTx: 26.7, 20.4–33.0; without CTx: 9.7, 5.2–14.1; p < .001). OS according to CRM status differed on a clinically relevant level by about 12 months (CRM positive: 17.2 months, 11.5–23.0; CRM negative: 29.8 months, 18.6–41.1; p = 0.126). A multivariate model containing chemotherapy, nodal status, and CRM explained long-term survival (p = 0.008; correct prediction >70%). Chemotherapy, nodal status and resection margin according to UICC R status are univariate factors for OS after PDAC. In contrast, long-term survival seems to depend on wider resection margins than those used in UICC R classification. Therefore, standardized histopathological reporting (including resection margin size) should be agreed upon.

Morphological speculation of the MHPD and related clinical projections

OBJECTIVE

The concept of mesopancreas has been brought into focus nowadays. Studies on membrane morphology of pancreas are clinically significant in determining an ideal surgical route for a "holy plane". In this paper, we aimed to observe the structure of the peripancreatic membranes and its interactions with adjacent tissues; tentatively put forward the proposition of mesohepatopancreaticoduodenum (MHPD) and explore in depth in surgical local resection.

METHODS

33 cadavers were examined in the experiment, including 30 for gross anatomy and 3 for histological observation after transection. The histological characteristics of the membrane covering the pancreas were proved by Masson and Bielschowsky silver staining and further explored in clinical application and testified in a surgical scenario. All above were carried out through traditional procedures.

RESULTS

The anterior surface membrane of the pancreas was intact and the posterior portion expanding to the pancreaticoduodenum enclosed the surface of the duodenum and the pancreatic head, which could be easily isolated from the posterior abdominal wall. The posterior surface membrane around the body and tail wrapped the pancreatic parenchyma, which created a soft-tissue window for the posterior abdominal wall. Then, dense connective tissue adhesions were detected between the celiac artery and the superior mesenteric artery.

CONCLUSIONS

The embryonic origin of the mesopancreas and the surgical procedures were reviewed and inspected based on the proposition of MHPD and above results. We hope that this study could stir up our interest in the advancement of imaging diagnoses and minimally invasive surgical treatment of pancreas.

Extended lymph node resection versus standard resection for pancreatic and periampullary adenocarcinoma

BACKGROUND

Pancreatic and periampullary adenocarcinomas account for some of the most aggressive malignancies, and the leading causes of cancer-related mortalities. Partial pancreaticoduodenectomy (PD) with negative resection margins is the only potentially curative therapy. The high prevalence of lymph node metastases has led to the hypothesis that wider excision with the removal of more lymphatic tissue could result in an improvement of survival, and higher rates of negative resection margins.

OBJECTIVES

To compare overall survival following standard (SLA) versus extended lymph lymphadenectomy (ELA) for pancreatic head and periampullary adenocarcinoma. We also compared secondary outcomes, such as morbidity, mortality, and tumour involvement of the resection margins between the two procedures.

SEARCH METHODS

We searched CENTRAL, MEDLINE, PubMed, and Embase from 1973 to September 2020; we applied no language restrictions.

SELECTION CRITERIA

Randomised controlled trials (RCT) comparing PD with SLA versus PD with ELA, including participants with pancreatic head and periampullary adenocarcinoma.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened references and extracted data from study reports. We calculated pooled risk ratios (RR) for most binary outcomes except for postoperative mortality, for which we estimated a Peto odds ratio (Peto OR), and mean differences (MD) for continuous outcomes. We used a fixed-effect model in the absence of substantial heterogeneity (I² < 25%), and a random-effects model in cases of substantial heterogeneity (I² > 25%). Two review authors independently assessed risk of bias, and we used GRADE to assess the quality of the evidence for important outcomes.

MAIN RESULTS

We included seven studies with 843 participants (421 ELA and 422 SLA). All seven studies included Kaplan-Meier curves for overall survival. There was little or no difference in survival between groups (log hazard ratio (log HR) 0.12, 95% confidence interval (CI) -3.06 to 3.31; P = 0.94; seven studies, 843 participants; very low-quality evidence). There was little or no difference in postoperative mortality between the groups (Peto odds ratio (OR) 1.20, 95% CI 0.51 to 2.80; seven studies, 843 participants; low-quality evidence). Operating time was probably longer for ELA (mean difference (MD) 50.13 minutes, 95% CI 19.19 to 81.06 minutes; five studies, 670 participants; moderate-quality evidence). There was substantial heterogeneity between the studies (I² = 88%; P < 0.00001). There may have been more blood loss during ELA (MD 137.43 mL, 95% CI 11.55 to 263.30 mL; two studies, 463 participants; very low-quality evidence). There was substantial heterogeneity between the studies (I² = 81%, P = 0.02). There may have been more lymph nodes retrieved during ELA (MD 11.09 nodes, 95% CI 7.16 to 15.02; five studies, 670 participants; moderate-quality evidence). There was substantial heterogeneity between the studies (I² = 81%, P < 0.00001). There was little or no difference in the incidence of positive resection margins between groups (RR 0.81, 95% CI 0.58 to 1.13; six studies, 783 participants; very low-quality evidence).

AUTHORS' CONCLUSIONS

There is no evidence of an impact on survival with extended versus standard lymph node resection. However, the operating time may have been longer and blood loss greater in the extended resection group. In conclusion, current evidence neither supports nor refutes the effect of extended lymph lymphadenectomy in people with adenocarcinoma of the head of the pancreas.

Detailed Analysis of Margin Positivity and the Site of Local Recurrence After Pancreaticoduodenectomy

BACKGROUND

The association between a positive surgical margin and local recurrence after resection of pancreatic adenocarcinoma (PDAC) has been reported. Assessment of the location of the a positive margin and the specific site of local recurrence has not been well described.

METHODS

A prospectively maintained database was queried for patients who underwent R0/R1 pancreaticoduodenectomy for PDAC between 2000 and 2015. The pancreatic, posterior, gastric/duodenal, anterior peritoneal, and bile duct margins were routinely assessed. Postoperative imaging was reviewed for the site of first recurrence, and local recurrence was defined as recurrence located in the remnant pancreas, surgical bed, or retroperitoneal site outside the surgical bed.

RESULTS

During the study period, 891 patients underwent pancreaticoduodenectomy, and 390 patients had an initial local recurrence with or without distant metastases. The 5-year cumulative incidence of local recurrence by site included the remnant pancreas (4%; 95% confidence interval [CI], 3-5%), the surgical bed (35%; 95% CI, 32-39%), and other regional retroperitoneal site (4%; 95% CI, 3-6%). In the univariate analysis, positive posterior margin (hazard ratio [HR], 1.50; 95% CI, 1.17-1.91; p = 0.001) and positive lymph nodes (HR, 1.36; 95% CI, 1.06-1.75; p = 0.017) were associated with surgical bed recurrence, and in the multivariate analysis, positive posterior margin remained significant (HR, 1.40; 95% CI, 1.09-1.81; p = 0.009). An isolated local recurrence was found in 197 patients, and a positive posterior margin was associated with surgical bed recurrence in this subgroup (HR, 1.51; 95% CI, 1.08-2.10; p = 0.016).

CONCLUSION

In this study, the primary association between site of margin positivity and site of local recurrence was between the posterior margin and surgical bed recurrence. Given this association and the limited ability to modify this margin intraoperatively, preoperative assessment should be emphasized.

Accurate prediction of severe postoperative complications after pancreatic surgery: POSSUM vs E-PASS

BACKGROUND/PURPOSE

Few reports have evaluated the differences in the predictive accuracy between the physiological and operative severity score for the enumeration of mortality and morbidity (POSSUM) and estimation of physiologic ability and surgical stress (E-PASS) in pancreatic surgery. Thus, we evaluated the accuracy and similarity of POSSUM and E-PASS for the prediction of severe postoperative complications (PCs) after pancreatic surgery.

METHODS

We enrolled 343 consecutive patients who underwent pancreatic surgery in our department between April 2006 and September 2017. The difference in predictive values of POSSUM and E-PASS for the occurrence of PCs ≥ Clavien-Dindo grade IIIa (PCs-CD ≥ IIIa) was nonparametrically compared. The predictive accuracy and similarity of each tool was examined using the receiver operating characteristic (ROC) curve and linear regression analyses.

RESULTS

Forty-five patients developed PCs-CD ≥ IIIa. E-PASS had a significantly higher predictive value for estimating PCs-CD ≥ IIIa occurrence (P = .002) than did POSSUM. The area under the curve value in ROC analysis was significantly higher in E-PASS than in POSSUM (0.643 vs 0.543, P = .014), with a weak positive correlation in the predictive value between E-PASS and POSSUM (R²  = .333, P < .001).

CONCLUSION

Estimation of physiologic ability and surgical stress was useful for predicting severe PCs after pancreatic surgery and had a higher accuracy than POSSUM.

En bloc proximal peri-mesenteric clearance for pancreatic head cancer surgery

The superior mesenteric artery (SMA) first approach and meso-pancreas excision (MPE) during pancreatoduodenectomy (PD) for pancreatic head cancer have been suggested for complete local tumor control, less operative blood loss, and early determination of resectability. However, SMA-first approach is merely a mode of approach and the concept of MPE has been challenged due to its anatomical obscurity. Dissection around proximal mesenteric vessels, superior mesenteric vein and SMA, is a critical procedure point for local tumor control as tumor infiltration is frequently observed both at the time of initial diagnosis and recurrence. The meso-pancreas, which encompasses the soft tissue between the uncinated process and SMA, does not include all the aforementioned points of proximal mesenteric areas. Therefore, the authors propose a new terminology named, “en bloc proximal peri-mesenteric clearance (PPMC)”, to describe the removal of all the lymph nodes including soft tissue around proximal mesenteric vessels, especially the SMA, to ensure complete local tumor control of pancreatic head cancer. The SMA-first approach applied either by the mesenteric approach or supra-colic approach can make this procedure more feasible. The extent of the circumferential dissection of the peri-SMA nerve plexus can be adjusted according to the primary disease. PPMC including the removal of all lymph nodes around the proximal SMA may be considered as a standard extent of PD for pancreatic head cancer.

Complete Lymphadenectomy Around the Entire Superior Mesenteric Artery Improves Survival in Artery-First Approach Pancreatoduodenectomy for T3 Pancreatic Ductal Adenocarcinoma

BACKGROUND

Artery-first approach pancreatoduodenectomy (AFA-PD) is an important technique for treating pancreatic ductal adenocarcinoma (PDAC). However, it remains unknown whether performing complete lymphadenectomy around the entire superior mesenteric artery (SMA) is associated with better outcomes. In this retrospective study, we aimed to investigate whether this approach improved overall and recurrence-free survival in patients with PDAC.

METHODS

We identified 88 patients with T3 PDAC who underwent PD at St. Marianna University School of Medicine, Kawasaki, Japan, between April 2005 and October 2017. Two groups were defined: an "AFA-PD group" (n = 45) who had undergone AFA-PD in addition to complete lymphadenectomy around the entire SMA, and a "conventional PD group" (n = 43) in whom complete lymphadenectomy had not been performed (conventional group). Univariate and multivariate survival analyses were performed to identify risk factors for overall and disease-free survival.

RESULTS

The AFA-PD group had a longer median survival time (40.3 vs. 22.6 months; p = 0.0140) and a higher 5-year survival rate (40.3% vs. 5.9%, p = 0.005) than the conventional PD group. Multivariate analysis showed that AFA-PD with complete lymphadenectomy around the entire SMA was an independent factor for improved overall survival (p = 0.022). Recurrences around the SMA were significantly less frequent in the AFA-PD group than in the conventional group (22.2% vs. 44.2%, p = 0.041).

CONCLUSIONS

AFA-PD with complete lymphadenectomy around the entire SMA can prevent recurrences around the SMA and may prolong overall survival in patients with PDAC.

An anatomical review of various superior mesenteric artery-first approaches during pancreatoduodenectomy for pancreatic cancer

When pancreatic head cancer invades the superior mesenteric artery (SMA), attempts at curative resection are aborted. Preoperative imaging diagnostics to determine the surgical curability have yet to surpass the intraoperative information acquired via inspection, palpation, and trial dissection. Pancreatoduodenectomy (PD) is a standard measure for treating periampullary cancers. In conventional PD, SMA invasion is usually identified by dissecting the retroportal lamina, which connects the uncinate process and SMA nerve plexus after dividing the neck of the pancreas. During PD for pancreatic head cancer, this retroperitoneal margin frequently vitiates surgical curability. SMA-first approaches during PD are methods where the SMA is dissected first by severing the posterior pancreatic capsule to assess the SMA involvement of pancreatic cancer early in the operation. The first report of such an approach prompted subsequent reports of various maneuvers that are now known collectively as "artery-first" approaches. We herein review those approaches by classifying them according to (1) the side of the mesocolon from where the SMA approach occurs (supracolic or infracolic) and (2) the direction of access (right or left and anterior or posterior). The steps of the reported PD procedures are numbered according to a timeline and summarized using anatomical division of the SMA.

The Prognostic Relevance of the Number and Location of Positive Lymph Nodes for Ampulla of Vater Carcinoma

BACKGROUND

Lymph node metastasis (LNM) has been regarded as one of the prognostic factors in patients with ampulla of Vater carcinoma (AC). However, the consensus about an optimal cutoff value of the number of LNMs and the definition of the regional lymph nodes (RLNs) has not been achieved.

METHODS

This study included 114 consecutive patients who underwent pancreatoduodenectomy for AC between January 2002 and March 2019.

RESULTS

The minimum p value approach for the greatest difference in the overall survival classified the number of LNM into none (N0, n = 66), from 1 to 2 (N1, n = 32), and ≥3 LNM (N2, n = 11) (p = 0.004). Distant LNM was defined as M1 (n = 5). Significant differences in relapse-free survival (RFS) were found between N0 and N1 (p < 0.001), N1 and N2 (p = 0.047), and N1 and M1 (p = 0.044) but not between N2 and M1 (p = 0.683). Moreover, the patients with regional LNM were classified into two groups: Np group (n = 35, LNM only in pancreatic head region) and Nd group (n = 8, LNM in other regional location). Significant differences in the RFS were found between N0 and Np (p < 0.001), Np and Nd (p = 0.004), and Np and M1 (p = 0.033) but not between Nd and M1 (p = 0.883). A Cox proportional hazards analysis for RFS revealed that ≥ 3 LNMs (hazards ratio [HR], 3.22) and LNM except for pancreatic head region (HR, 4.27) were individually independent worse prognostic factors.

CONCLUSIONS

≥3 LNMs and regional LNM except for pancreatic head region were associated with poor prognosis comparable to that of the patients with M1.

The mesopancreas and pancreatic head plexus: morphological, developmental, and clinical perspectives

PURPOSE

Total mesopancreas excision has been found to be helpful for increasing no residual tumor resection rate and improving the prognosis of pancreatic cancer. This study analyzed the relationships among the mesopancreas and pancreatic head plexus from the morphological, developmental, and clinical perspectives.

METHODS

Twenty-four cadavers were employed. The upper abdominal viscera were resected en-bloc with the hepatoduodenal ligament, abdominal aorta, and nerve plexuses, and the innervation of the pancreas was dissected. Ten additional cadavers were used for histological examination of the pancreatic head and neck, part of the duodenum, the superior mesenteric artery (SMA) and its surrounding tissues, and the related arteries and veins.

RESULTS

As results, cross-sections of the SMA revealed 6-9 layers of membranous structures resembling the layers of an onion, and the nerve fibers of the superior mesenteric plexus ran between the layers. Loose areolar tissue, adipose tissue, and lymphatics existed between the SMA and the pancreatic head/uncinate process, along with abundant thin blood vessels and capillaries, but very few nerves were found approaching the pancreas. Several parallel layers of collagen fibers (so-called Treitz's fusion fascia) existed between the dorsal aspect of the pancreatic head and the aortocaval plane.

CONCLUSION

The mesopancreas was continuous and connected with the para-aortic area. It may be better termed the mesopancreatoduodenum than the mesopancreas, as the duodenum-pancreas-SMA forms a complex morphological, developmental, functional, and pathological structure.

Prognostic significance of regional lymph node metastasis according to station in ampullary carcinoma

BACKGROUND

The TNM (Tumor, Node, Metastasis) classification of the 8th Union for International Cancer Control and the 6th Japanese classification of biliary tract cancer were made on the premise that the prognostic effect of each regional lymph node station is similar. However, some studies have reported different effects of lymph node metastasis location on post-resection prognosis. This study aimed to investigate outcome following radical resection of ampullary carcinoma according to station of lymph node metastasis.

METHODS

Patients who underwent surgical resection for ampullary carcinoma between January 2007 and December 2017 at two separate Japanese institutions were included. Regional lymph nodes were subclassified as follows: Pancreatoduodenal lymph nodes (PD) and others (OT).

RESULTS

Of the 101 patients analyzed, 34 had regional lymph node metastasis. OT metastasis was found in eight patients. Significant differences were found in relapse-free survival (RFS) and overall survival (OS) between the three study groups (no nodal metastasis, only PD metastasis and OT metastasis; P < .001 for both). OT metastasis was an independent prognostic factor in the multivariate analysis for RFS (hazard ratio [HR] 17.14; 95% confidence interval [CI], 6.33-43.93) and OS (HR 11.06; 95% CI, 3.7-32.99).

CONCLUSION

The poor prognosis of ampullary carcinoma patients with OT metastasis suggests that regional lymph nodes should not be categorized equally into one group.

Laparoscopic versus open radical antegrade modular pancreatosplenectomy with artery-first approach in pancreatic cancer

BACKGROUND

An artery-first approach for pancreatic cancer (PC) is challenging to perform laparoscopically and is mainly performed using an open approach. The aims of this study were to assess the safety and feasibility of laparoscopic radical antegrade modular pancreatosplenectomy (RAMPS) with an artery-first approach (L-aRAMPS) as compared with open aRAMPS (O-aRAMPS) in resectable PC using matched-pair analysis.

METHODS

Artery-first approach is an early dissection of the superior mesenteric artery (SMA) from behind the pancreas body as the first surgical step. Data on L-aRAMPS and O-aRAMPS, performed between July 2013 and November 2019, were collected retrospectively. Additionally, the spatial characteristics of the splenic artery were analyzed using computed tomography.

RESULTS

Thirty L-aRAMPS and 33 O-aRAMPS for resectable PC were included. After matching, 15 L-aRAMPS were compared with 15 O-aRAMPS. Median intraoperative blood loss and hospital stay were significantly improved in L-aRAMPS compared to O-aRAMPS (30 vs. 220 g, p < 0.001; 12 vs. 16 days, p = 0.049). The overall morbidity was similar in both study groups. The total number of lymph nodes dissected and those harvested from around the SMA and R0 resection was similar in both study groups. We classified the width of the cross section of the pancreas body into three equal parts: the upper, middle, and lower parts of the pancreas; 63% of the splenic artery origin was located in middle and lower parts of the pancreas body.

CONCLUSION

L-aRAMPS is technically safe and oncologically feasible to secure favorable surgical outcomes for resectable PC patients.

The Main Bottleneck for Non-Metastatic Pancreatic Adenocarcinoma in Past Decades: A Population-Based Analysis

BACKGROUND Despite recent advancements in surgical techniques, chemotherapy, and radiotherapy, the 5-year survival rate of patients with pancreatic ductal adenocarcinoma (PDAC) remains an unsatisfactory ~8%. MATERIAL AND METHODS Data were extracted to identify patients with non-metastatic pancreatic adenocarcinoma diagnosed in the periods 1988-1996 and 2010-2014 in the Surveillance, Epidemiology, and End Results (SEER) database. The statistical analyses were performed with the log-rank test, Pearson's chi-square test, propensity score matching, and Cox regression model. RESULTS The hazard ratio (HR) of surgery was reduced from 0.454 to 0.302 in Cox regression modeling, and there was no overlapping about the 95% confidence intervals (CI) of surgery between the 2 periods. The HR values of radiotherapy, which were new prognostic factor for resectable PDAC in 2010-2014, were reduced in both the resectable and unresectable groups. The upgraded chemotherapy regimen reduced the HR values from 0.738 to 0.689 in all PADC patients, and from 0.656 to 0.588 in unresectable PDAC. The log-rank test results showed that advances in surgery significantly improved the median survival from 13 months to 32 months. Radiotherapeutic and chemotherapeutic advancements extended median survival by 12 months and 11 months, respectively, in resectable PDAC. The median survivals were extended by 3 months for both of radiotherapy and chemotherapy in unresectable PDAC. CONCLUSIONS The development of chemotherapy and radiotherapy has been slow, especially for unresectable PDAC. Although advances in surgery contributed significantly to improved survival for resectable PDAC, lack of early diagnostic tools, which lead to low resection rates, remain a barrier for all PDAC patients.

Total mesopancreas excision for periampullary malignancy: a single-center propensity score-matched comparison of long-term outcomes

PURPOSE

Few comparative studies are available on the long-term prognostic role of mesopancreas (MP) excision after pancreaticoduodenectomy (PD). We compared the long-term outcomes of patients undergoing standard PD (sPD) and PD with MP excision (PD-MPe).

METHODS

Sixty sPDs were compared to 60 matched PD-MPe patients for intraoperative and postoperative data, histopathological findings, and long-term outcomes.

RESULTS

R0 rate was similar in the two groups (p = 0.17). However, PD-MPe related to a lower rate of MP resection margin positivity (16.7% vs 5%; p = 0.04) and to a higher harvested lymph nodes number (19.8 ± 7.6 vs 10.1 ± 5.1; p < 0.0001). Local tumor recurrence was more frequent in the sPD cohort (55.5% vs 26.8% in the PD-MPe group; p = 0.002), with a consequent worse disease-free survival (DFS) (14.8% vs 22.3%; p = 0.04). An inferior 5-year overall survival (OS) was noted in case of MP margin positivity compared with MP margin negativity (0% vs 29%; p < 0.0001). MP positivity resulted as an independent prognostic factor for both a worse OS and DFS at the multivariate analysis.

CONCLUSION

PD-MPe offers clinical advantages in terms of MP resection margin status, local recurrence, long-term mortality, and DFS. The lower MP positivity rate, achieved with PD-MPe, leads to better outcomes both in terms of OS and DFS.

Impact of resection margins on long-term survival after pancreaticoduodenectomy for pancreatic head carcinoma

BACKGROUND

The impact of resection margin status on long-term survival after pancreaticoduodenectomy (PD) for patients with pancreatic head carcinoma remains controversial and depends on the method used in the histopathological study of the resected specimens. This study aimed to examine the impact of resection margin status on the long-term overall survival of patients with pancreatic head carcinoma after PD using the tumor node metastasis standard.

METHODS

Consecutive patients with pancreatic head carcinoma who underwent PD at the Chinese People's Liberation Army General Hospital between May 2010 and May 2016 were included. The impact of resection margin status on long-term survival was retrospectively analyzed.

RESULTS

Among the 124 patients, R0 resection was achieved in 85 patients (68.5%), R1 resection in 38 patients (30.7%) and R2 resection in 1 patient (0.8%). The 1- and 3-year overall survival (OS) rates were significantly higher for the patients who underwent R0 resection than the rates for those who underwent R1 resection (1-year OS rates: 69.4% vs 53.0%; 3-year OS rates: 26.9% vs 11.7%). Multivariate analysis showed that resection margin status and venous invasion were significant risk factors for OS.

CONCLUSION

Resection margin was an independent risk factor for OS for patients with pancreatic head carcinoma after PD. R0 resection was associated with significantly better OS after surgery.

Superior mesenteric artery first approach can improve the clinical outcomes of pancreaticoduodenectomy: A meta-analysis

BACKGROUND AND AIM

Superior mesenteric artery (SMA) first approach was a new improvement for pancreaticoduodenectomy (PD), but there is no evidence whether this approach is advantageous to PD. This meta-analysis aimed to determine the effects of the superior mesenteric artery (SMA) first approach on outcomes of pancreaticoduodenectomy (PD).

METHODS

Literature searches were conducted on PubMed, The Cochrane Library, EMBASE, Web of Science, Clinical Trials Registry and China Biology Medicine disc. We completed a meta-analysis of the SMA first approach in PD, assessing overall survival, R0 resection, blood loss, postoperative complications, operation time and postoperative stay. The odds ratios and weighted mean differences with 95% confidence intervals (CIs) were pooled.

RESULTS

Eighteen studies comprising 1483 participants were included. Patients who received SMA-PD had significantly lower overall complication rate (OR 0.62, 95% CI 0.47 to 0.81, P = 0.001) and less blood loss (WMD -264.84, 95% CI -336.1 to -193.58, P < 0.001). The obviously increased R0 resection rate (OR 2.92, 95% CI 1.72 to 4.96, P < 0.001) and 3-year OS (OR 2.15, 95% CI 1.34 to 3.43, P = 0.001) were found in the SMA-PD group.

CONCLUSION

The SMA-PD group had better clinical outcomes, particularly in long-term survival of pancreatic cancer patients; furthermore, the patients acquired superior clinical efficacy via the posterior approach in SMA-PD.

Survival, morbidity and mortality of pancreatic adenocarcinoma after pancreaticoduodenectomy with a total mesopancreas excision

INTRODUCTION

pancreatic adenocarcinoma is the most common malignancy in the periampullary region, with a five-year survival rate around 20%.

OBJECTIVE

the goal of our study was to determine the survival and safety data of a number of patients that underwent a cephalic duodenopancreatectomy (CDP) with total mesopancreas excision (TMPE).

MATERIAL AND METHODS

a prospective observational study was performed of 114 patients with pancreatic adenocarcinoma who underwent duodenopancreatectomy and TMPE over the period 2008-2017. Demographic variables, tumor stage, number of lymph nodes excised, lymph node ratio, R classification, the prognostic factor disease-free interval and survival were all assessed in a multivariate analysis.

RESULTS

complications were reported for 54 (47.3%) patients, of which 22 (19.3%) were categorized as serious. The mortality rate was 4.3% and the mean follow-up was 26.2 months. During this period, 73 (64%) patients relapsed after a mean interval of 40.9 months. The relapse pattern was mainly hepatic (26.3%), followed by local relapse (20%). Mean survival was 40.38 and actuarial survival was 26.6% at five years. Relapse-related factors included stage T3 or higher (RR 8.1 [1.1-61]) and an R1 resection (RR 13.4 [2.7-66.5]) and survival-related factors included an R1 resection (RR 10.7 [2.5-46.2]).

CONCLUSION

TMPE ensures an adequate lymphadenectomy and lymph node ratio according to reported standards. The survival of patients that have undergone surgery for pancreatic adenocarcinoma in our institution is 68.4% at one year and 26.6% at five years. An R1 resection is the primary factor for both relapse and survival.

Management of pancreatic head adenocarcinoma: From where to where?

Pancreatic head adenocarcinoma (PHAC) is one of the most aggressive malignancies, and it has low long-term survival rates. Surgery is the only option for long-term survival. The difficulties associated with PHAC include higher frequencies of regional or distant lymph node metastases and vascular involvement, and positive resection margins in pancreatic and retroperitoneal tissues. Radical resections increase margin negativity and life expectancy; however, the extend of the surgery applied is controversial. Thus, western and eastern centers may use different approaches. Multiorgan, peripancreatic nerve plexus, and vascular resections have been discussed in relation to radical surgery for pancreatic cancer as have the roles of neoadjuvant and adjuvant therapy regimens. Determining the appropriate limits for surgery, standardizing definitions and surgical techniques according to guidelines, and centralizing pancreatic surgery within high-volume institutions to reduce mortality and morbidity rates are among the most important issues to consider. In this review, we evaluate the basic concepts underlying and the roles of radical surgery for PHAC, and lymphadenectomy, nerve plexus, retroperitoneal tissue, vascular, and multivisceral resections, total pancreatectomy, and liver metastases are discussed.

Pancreatoduodenectomy with artery-first approach

"Artery-first approach" encompasses different aspects for the surgical treatment of pancreatic cancer. It is a surgical technique or set of techniques which share in common the dissection of the main arterial vasculature involved in pancreatic cancer, before any irreversible surgical step is performed. On the other hand it represents the need for a meticulous dissection of the arterial planes and clearing of the retropancreatic tissue between the superior mesenteric artery, the common hepatic artery and portal vein in an attempt to achieve R0 resections. The recent expansion of this approach is based mainly on three factors: venous involvement should not be considered a contraindication for resection, most of the pancreatic resections performed with a standard procedure may be in fact non-oncological (R1) resections and the postero-medial or vascular margin is the most frequently invaded by the tumor. This review aimed to summarize and update the artery-first approach in pancreaticoduodenectomy.

MAPLE-PD trial (Mesenteric Approach vs. Conventional Approach for Pancreatic Cancer during Pancreaticoduodenectomy): study protocol for a multicenter randomized controlled trial of 354 patients with pancreatic ductal adenocarcinoma

Background

The mesenteric approach is an artery-first approach to pancreaticoduodenectomy for pancreatic cancer, which starts with the dissection of connective tissues around the superior mesenteric artery. The procedure aims for early confirmation of resectability by checking the surgical margin around the superior mesenteric artery first during the operation. It also aims to decrease intraoperative blood loss by early ligation of the inferior pancreaticoduodenal artery and to increase R0 rate by complete clearance of the lymph nodes around the superior mesenteric artery and pancreatic head plexus II, the most favorable positive margin site for pancreatic ductal adenocarcinoma. Furthermore, it aims to avoid the spread of cancer cells during operation (nontouch isolation technique). The MAPLE-PD (Mesenteric Approach vs. Conventional Approach for Pancreatic Cancer during Pancreaticoduodenectomy) trial investigates whether the mesenteric approach can prolong the survival of patients with pancreatic ductal adenocarcinoma who undergo pancreaticoduodenectomy compared with the conventional approach.

Methods/design

The MAPLE-PD trial is a Japanese multicenter randomized controlled trial that compares the surgical outcomes between the mesenteric and conventional approaches to pancreaticoduodenectomy. Patients with pancreatic ductal adenocarcinoma scheduled to undergo pancreaticoduodenectomy are randomized before operation to either a conventional approach (arm A) or a mesenteric approach (arm B). In arm A, the operation starts with Kocher’s maneuver. At the final step of the removal procedure, the connective tissues around the superior mesenteric artery are dissected. In arm B, the operation starts with dissection of the connective tissues around the superior mesenteric artery and ends with Kocher’s maneuver. In total, 354 patients from 15 Japanese high-volume centers will be randomized. The primary endpoint is overall survival by intention-to-treat analysis. Secondary endpoints include intraoperative blood loss, R0 rate, and recurrence-free survival.

Discussion

If the MAPLE-PD trial shows the oncological benefits of the mesenteric approach for patients with pancreatic ductal adenocarcinoma, this procedure may become a standard approach to pancreaticoduodenectomy.

Trial registration

ClinicalTrials.gov, NCT03317886. Registered on 23 October 2017.

University Hospital Medical Information Network Clinical Trials Registry, UMIN000029615. Registered on 15 January 2018.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-3002-z) contains supplementary material, which is available to authorized users.

Systematic review of the mesopancreas: concept and clinical implications

BACKGROUND

In 2007, Gockel et al. coined the term mesopancreas (MP). In the next 10 years, a limited number of publications about MP have been published, but little is known about the oncological benefit of MP resection. We performed a systematic review of the literature on MP.

METHODS

An electronic search was performed in PubMed, EMBASE, Cochrane, Latindex, Scielo, and Koreamed databases until 15 June 2017 to identify all published articles dealing with the subject of MP. Some language restriction was done (Chinese and Rumanian).

RESULTS

The search yielded 51 articles; 28 articles were selected as relevant. All were retrospective studies focused more on describing technical variants, feasibility and safety than on the cancer results. The R0 rate in patients with MP resection ranged between 57 and 96.7%. In all the articles with a control group, the R0 rate was higher in the MP excision group. Survival data were explicitly stated only in five series.

CONCLUSION

MP is a difficult-to-excise retropancreatic area. In theory, it is agreed that MP excision raises the rate of R0 resections, which in turn reflected in an improvement in the oncological results; however, at present there are no randomized studies to prove this. Achieving a worldwide consensus on its concept, landmarks, excision technique and oncological results is essential.

Total mesopancreas excision for the treatment of pancreatic head cancer

Mesopancreas is a controversial structure. This study aimed to explore the anatomical characteristics of the mesopancreas, define the range of the total mesopancreas excision (TMpE), and evaluate the feasibility, safety and effectivity of TMpE in the treatment of pancreatic head cancer. The clinical and pathological data of 58 consecutive patients undergoing TMpE for pancreatic head carcinoma from January 2013 to December 2015 were analyzed prospectively. The perioperative morbidity, mortality and clinical outcomes of patients undergoing TMpE were compared with the patients undergoing conventional pancreaticoduodenectomy. The mesopancreas was located in the retropancreatic area, extending from the head, neck, and uncinated process of pancreas to the aorto-caval groove, in which there were loose areolar tissue, adipose tissue, nerve plexus, lymphatic and capillaries. We observed significantly higher R0 rate (94.8% vs. 81.4%, P=0.035), more lymph nodes (16.2 vs. 11.4, P=0.000), lower total and local recurrence rate (half-year local recurrence rate 7.8% vs. 23.7%, P=0.036, one-year 18.2% vs. 39.5%, P=0.018) and longer disease-free survival (16.9 vs. 13.4 months, P=0.044) in TMpE group than in control group. In conclusion, mesopancreas is different from mesorectum because there is no fascial envelop or anatomical boundary in this area. TMpE could be safely and feasibly performed for the treatment of pancreatic head cancer to increase the R0 resection rate and improve the clinical outcomes.

Mesenteric approach during pancreaticoduodenectomy for pancreatic ductal adenocarcinoma

Mesenteric approach is an artery‐first approach during pancreaticoduodenectomy (PD). In the present study, we evaluated clinical and oncological benefits of this procedure for pancreatic ductal adenocarcinoma (PDAC) of the pancreas head. Between 2000 and 2015, 237 consecutive PDAC patients underwent PD. Among them, 72 experienced the mesenteric approach (mesenteric group) and 165 the conventional approach (conventional group). A matched‐pairs group consisted of 116 patients (58 patients in each group) matched for age, gender, resectability status, and neoadjuvant therapy. Surgical and oncological outcomes were compared between the two groups in unmatched‐ and matched‐pair analyses. Intraoperative blood loss was lower in the mesenteric group than in the conventional group in both resectable PDAC (R‐PDAC) and borderline resectable PDAC (BR‐PDAC) on unmatched‐ and matched‐pairs analyses (R‐PDAC, unmatched: 312.5 vs 510 mL, P=.008; matched: 312.5 vs 501.5 mL, P=.023; BR‐PDAC, unmatched: 507.5 vs 935 mL, P<.001; matched: 507.5 vs 920 mL, P=.003). Negative surgical margins (R0) and overall survival (OS) rates in the mesenteric group were better in R‐PDAC patients (R0 rates, unmatched: 100% vs 87.7%, P=.044; matched: 100% vs 86.7%, P=.045; OS, unmatched: P=.008, matched: P=.021), although there were no significant differences in BR‐PDAC patients. Mesenteric approach might reduce blood loss by early ligation of the vessels to the pancreatic head. Furthermore, it might increase R0 rate, leading to improvement of survival for R‐PDAC patients. However, R0 and survival rates could not be improved only by the mesenteric approach for BR‐PDAC patients. Therefore, effective multidisciplinary treatment is essential to improve survival in BR‐PDAC patients.

Location of the meso-pancreatoduodenum as a regional lymphatic basin for pancreatic head carcinoma

The meso-pancreatoduodenum is the primary site of tumor infiltration in patients with pancreatic head cancer, with numerous patients exhibiting lymph node metastases. Effective dissection of the regional lymphatic basin requires knowledge of the patterns of the arterial branches. The present study examined the patterns of the arteries feeding the pancreatic head and the distribution of the meso-pancreatoduodenum. The present study included 123 patients with pancreatic cancer who underwent contrast-enhanced preoperative 64-multidetector-computed tomography to determine the routes of the inferior pancreaticoduodenal and first jejunal arteries. Surgical specimens and cadavers were also evaluated histologically to clarify the distribution of the meso-pancreatoduodenum. The feeding arteries were divided into three types, with 64.2% of patients having type A, 28.4% having type B and 7.3% having type C branches. The branches emerged from the back or left side of the superior mesenteric artery and ran to the far side of the pancreatic head in an arc. Consequently, the meso-pancreatoduodenum had a roll-shaped appearance, surrounding the trunk arteries and extending to the left side of the superior mesenteric artery. Dissecting the right and left sides of the superior mesenteric artery during lymphadenectomy could improve the effectiveness of resection.

Superior mesenteric artery first approach versus standard pancreaticoduodenectomy: a systematic review and meta-analysis

BACKGROUND

The superior mesenteric artery (SMA) first approach was proposed recently as a new modification of the standard pancreaticoduodenectomy. Increasing evidence showed that a periadventiceal dissection of the SMA with early transection of the inflow during pancreaticoduodenectomy associates better early perioperative results, and setup the scene for long-term oncological benefits. The objectives of the current study are to compare the operative results and long-term oncological outcomes of SMA first approach pancreaticoduodenectomy (SMA-PD) with standard pancreaticoduodenectomy (S-PD).

DATA SOURCES

Electronic search of the PubMed/MEDLINE, EMBASE, Web of Science and Cochrane Library was performed until July 2015. We considered randomized controlled trials (RCTs) and non-randomized comparative studies (NRCSs) comparing SMA-PD with S-PD to be eligible if they included patients with periampullary cancers.

RESULTS

A total of one RCT and thirteen NRCSs met the inclusion criteria, involving 640 patients with SMA-PD and 514 patients with S-PD. The SMA-PD was associated with less intraoperative bleeding, less blood transfusions and higher rate of associated venous resections. The pancreatic fistula and delayed gastric emptying had a significantly lower rate in the SMA-PD group. There were no differences between the two approaches regarding overall complications, major complication rates and in-hospital mortality. There was no difference regarding R0 resection rate, and one-, two- or three-year overall survival. The SMA-PD was associated with a lower local, hepatic and extrahepatic metastatic rate.

CONCLUSIONS

The SMA-PD is associated with better perioperative outcomes, such as blood loss, transfusion requirements, pancreatic fistula, and delayed gastric emptying. Although the one-, two- or three-year overall survival rate is not superior, the SMA-PD has a lower local and metastatic recurrence rate.

Liver parenchyma transection-first approach in hemihepatectomy with en bloc caudate lobectomy for hilar cholangiocarcinoma: A safe technique to secure favorable surgical outcomes

BACKGROUND

Although hemihepatectomy with total caudate lobectomy (hemiHx-tc) is essential for the surgical treatment of hilar cholangiocarcinoma, the advantage of an anterior approach for hemiHx-tc has not been fully discussed technically; the significance of an anterior approach without liver mobilization for preventing infectious complications also remains unknown.

METHODS

The liver parenchyma transection-first approach (Hp-first) technique is an early transection of the hepatic parenchyma without mobilization of the liver that utilizes a modified liver-hanging maneuver to avoid damaging the future remnant liver.

RESULTS

Between May 2010 and August 2016, a total of 40 consecutive patients underwent surgery for hilar cholangiocarcinoma. Of these, 19 patients underwent a conventional hemihepatectomy with total caudate lobectomy (cHx), while 21 patients received a Hp-first. The patients in the Hp-first group had significantly less intraoperative blood loss (P < 0.001) and blood transfusion (P < 0.001), a lower incidence of postoperative hyperbilirubinemia (p = 0.023), a lower incidence of liver failure (p = 0.038), a lower hospital death rate (p = 0.042), and a better 2-year disease-free survival rate (p = 0.010) than those in the cHx group.

CONCLUSIONS

The liver parenchyma transection-first approach is the preferred technique for hemiHx-tc in hilar cholangiocarcinoma because it resulted in improved surgical outcomes as compared with the conventional approach.

Mesopancreas is a misnomer: time to correct the nomenclature

Focused pathological attention to tumor invasion of the retroperitoneal resection margin after pancreaticoduodenectomy for cancer of head of the pancreas led to the knowledge of strong tendency of cancer cells to infiltrate into the retropancreatic tissue and to spread along the peripancreatic neural plexuses as the cause of local recurrence. The term 'mesopancreas' was coined to describe perineural lymphatic layer located dorsally to the pancreas and it was suggested that its complete resection will minimize loco-regional recurrence and improve outcome. This catchy title and concept attracted the attention of surgeons and "total meso-pancreas excision" was introduced by 'artery first' or 'posterior first' surgical techniques to ensure 'en-bloc' extended resection of retropancreatic lymphatics. However, mesopancreas is a misnomer and cannot be called a 'true' mesentery as it does not have a fascial envelope attaching the pancreas to the posterior wall of the abdomen and does not contain 'all' its blood vessels and 'all' its primary draining lymphatics and lymph nodes. Japan Pancreas Society's description of pancreatic head plexus II is anatomically consistent with 'mesopancreas' and it should be renamed as such. This nomenclature clearly illustrates its exact anatomical location and surgical relevance; and stands up to necessary rigorous scientific scrutiny.

Survival advantage with para aortic lymphadenectomy in peri-ampullary cancer: A retrospective cohort study

BACKGROUND

Metastatic para aortic lymph nodes (PALN) in patients with peri ampullary cancer entail poor prognosis. Role of curative surgery in these patients remains debatable. The objective of the current study was to evaluate outcome after extended pancreaticoduodenectomy (PD) in patients with and without positive PALN.

METHODS

We reviewed 65 patients who underwent extended PD with PALN removal between 2011 and 2014. Patients were divided into two groups; those with positive PALN and those without. Patients were sub classified for pancreatic and non-pancreatic cancer. Outcome was determined based on median and estimated 3 year overall survival.

RESULTS

Median age was 57 (32-85) years. PALN were involved in 15 (23%) patients. Overall 3 year survival for patients with and without positive PALN was 60% and 54% (P = 0.7). Significant difference in survival was present between patients with pancreatic cancer and positive PALN [9 (3-12) months] versus non-pancreatic cancers with positive PALN [17.5 (13-38) months] (P = 0.02). Four out of five patients with pancreatic cancer and positive PALN had survival >6 months and 3 out of these 5 patients were alive at the last follow up.

CONCLUSION

Curative surgery may benefit some patients with pancreatic cancer and positive PALN and should be considered selectively.

The Standardization of Pancreatoduodenectomy: Where Are We?

Pancreaticoduodenectomy (PD) represents an important challenge for surgeons due to the complexity of the operation, requirement for technical skills and experience, and postoperative management involving important and life-threatening complications. Despite efforts to reduce mortality in high-volume centers, the morbidity rate is still high (approximately 40-50%). The PD standardization process of surgical aspects and preoperative and postoperative settings is essential to permit pancreatic surgeons to communicate in the same language, compare experiences and results, and to improve the short- and long-term outcomes. The aim of this article is to assess the state of the art practices for important matters of debate for PD (the role of mini invasive approach, the definition and the role of mesopancreas, the extent of lymphadenectomy, the different methods of reconstructions, the prophylactic drainage of the abdominal cavity), and to suggest possible future studies.

Modified total meso-pancreatoduodenum excision with pancreaticoduodenectomy as a mesopancreatic plane surgery in borderline resectable pancreatic cancer

BACKGROUND

A superior mesenteric artery (SMA)-first approach has been considered to be an efficient technique in pancreaticoduodenectomy when the SMA is a factor of borderline resectable pancreatic head cancer (BRPHC). However, this excellent procedure has limitations in terms of tumor resection with an intact coverage including the pancreatic tumor and the tumor-draining lymphovascular systems and the ability to achieve a complete regional lymphadenectomy.

METHODS

A modified mesenteric plane procedure has been developed that provides improved regional lymphadenectomy and permits adjustment of the surgical approach, which is based on the direction of the tumor infiltration.

RESULTS

Of 55 patients taken to surgery, 19 had peritoneal dissemination and/or liver metastasis at staging laparoscopy, and the procedure revealed tumor infiltration to the SMA and/or hepatic artery (HA) in 4 patients. Finally, 32 patients with BRPHC have undergone the procedure between April 2009 and June 2015. Twenty-four of 32 patients (75.0%) had negative resection margins, and the median number of lymph nodes harvested was 34. Lymph nodes around the SMA tested positive for metastasis in 13 patients (40.6%), and those around the HA tested positive for metastasis in 7 patients (21.9%). Complications occurred in 14 patients (43.7%), with no perioperative mortality. Overall survival rates were 65.3% at 1 year and 35.2% at 3 years.

CONCLUSIONS

Short-term results with the procedure may encourage surgical management for BRPHC.