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

Mesopancreas-Anatomical Insights and Its Implications for Diagnosis and Clinical and Surgical Practice

Background: The concept of mesopancreas is frequently discussed in the surgical literature as the neural pathway for metastatic spread in pancreatic head cancer. It generally refers to a retro-pancreatic plane that should be resected to reduce the incidence of regional metastases. However, this concept remains poorly defined, both embryologically and anatomically. Our objective was to establish a clear embryological and anatomical definition of the mesopancreas, making anatomical data more applicable in surgical practice. Methods: We examined seven cadavers (5 males, 2 females, aged 62-71) with no medical or surgical history, preserved in 9% formalin at Carol Davila University's Anatomy Department. Regional dissections were performed in successive planes, highlighting the celiac ganglia and the associated network of neural connections that comprise the mesopancreas. Results: Our study defines the "mesopancreas" as remnants of primordial mesenteries that coalesced into the Treitz fascia. We identified its functional components as nerve fibers linking the celiac ganglia and superior mesenteric plexus to the pancreas, along with vascular structures, lymphatics, and connective and adipose tissue. These components likely contribute to regional metastasis in pancreatic head cancer. While resection of the mesopancreas could help prevent metastasis, its complex anatomy and proximity to major vessels pose significant surgical challenges. Conclusions: Based on our findings, we propose a plausible definition for the term "mesopancreas". It encompasses the structures that originated as part of the primordial mesenteries, which subsequently coalesced, resulting in the formation of the Treitz fascia. In essence, the mesopancreas is the functional content of a former mesentery.

Technical Guidelines for Safe Mesojejunum Dissection During Pancreaticoduodenectomy: Unveiling Critical Techniques in a Complex Procedure

BACKGROUND

Pancreaticoduodenectomy (PD) is a complex procedure involving the dissection of the superior mesenteric artery and vein. However, a safe and standardized technique for dissecting the jejunal veins (JVs) in the mesojejunum during PD remains elusive.

METHODS

We retrospectively analyzed 198 patients who underwent open PD with mesojejunum dissection using an anterior artery-first approach and evaluated anatomical variations in the first JV trunk (FJVT) and its tributaries. This study introduces the concept of a "dangerous crossover vein" (DCV) to describe tributaries that cross the transection line of the mesojejunum. Surgical techniques and perioperative outcomes were assessed.

RESULTS

The FJVT drained the territory supplied by the first to second jejunal arteries in 144 patients (75%) and the first to third or more in 50 patients (25%). The FJVT was preserved in 100 patients (50.5%) and sacrificed in 98 (49.5%). Dangerous crossover veins were encountered in 117 patients (59%) and safely managed with standardized mesojejunal dissection. There were no significant differences in blood loss or operative time between patients with or without DCVs.

CONCLUSIONS

Understanding the anatomy of JVs and the concept of DCVs is critical for safe mesojejunal dissection during PD. Our approach facilitates secure dissection of JVs regardless of their anatomical variations.

Comparison of the different versions of NCCN guidelines for predicting margin-negative resection of pancreatic cancer in patients undergoing upfront surgery

OBJECTIVES

The purpose of this study was to compare the different versions of the National Comprehensive Cancer Network (NCCN) guidelines for defining resectability of pancreatic ductal adenocarcinoma (PDAC) in predicting margin-negative (R0) resection, and to assess inter-reader agreement.

METHODS

This retrospective study included 283 patients (mean age, 65.1 years ± 9.4 [SD]; 155 men) who underwent upfront pancreatectomy for PDAC between 2017 and 2019. Two radiologists independently determined the resectability on preoperative CT according to the 2017, 2019, and 2020 NCCN guidelines. The sensitivity and specificity for R0 resection were analyzed using a multivariable logistic regression analysis with generalized estimating equations. Inter-reader agreement was assessed using kappa statistics.

RESULTS

R0 resection was accomplished in 239 patients (84.5%). The sensitivity and specificity averaged across two readers were, respectively, 76.6% and 29.5% for the 2020 guidelines, 74.1% and 32.9% for the 2019 guidelines, and 72.6% and 34.1% for the 2017 guidelines. Compared with the 2020 guidelines, both 2019 and 2017 guidelines showed significantly lower sensitivity for R0 resection (p ≤ .009). Specificity was significantly higher with the 2017 guidelines (p = .043) than with the 2020 guidelines. Inter-reader agreements for determining the resectability of PDCA were strong (k ≥ 0.83) with all guidelines, being highest with the 2020 guidelines (k = 0.91).

CONCLUSION

The 2020 NCCN guidelines showed significantly higher sensitivity for prediction of R0 resection than the 2017 and 2019 guidelines.

Pancreaticoduodenectomy with superior mesenteric artery first-approach combined total meso-pancreas excision for periampullary malignancies: A high-volume single-center experience with short-term outcomes

Backgrounds/Aims

Pancreaticoduodenectomy (PD) is the only radical treatment for periampullary malignancies. Superior mesenteric artery (SMA) first approach combined with total meso-pancreas (MP) excision was conducted to improve the oncological results. There has not been any previous research of a technique that combines the SMA first approach and total MP excision with a detailed description of the MP macroscopical shape.

Methods

We prospectively assessed 77 patients with periampullary malignancies between October 2020 and March 2022 (18 months). All patients had undergone PD with SMA first approach combined total MP excision. The perioperative indications, clinical data, intra-operative index, R0 resection rate of postoperative pathological specimens (especially mesopancreatic margin), postoperative complications, and follow-up results were evaluated.

Results

The median operative time was 289.6 min (178-540 min), the median intraoperative blood loss was 209 mL (30-1,600 mL). Microscopically, there were 19 (24.7%) cases with metastatic MP, and five cases (6.5%) with R1-resection of the MP. The number of lymph nodes (LNs) harvested and metastatic LNs were 27.2 (maximum was 74) and 1.8 (maximum was 16), respectively. Some (46.8%) patients had pancreatic fistula, but mostly in grade A, with 7 patients (9.1%) who required re-operations. Some 18.2% of cases developed postoperative refractory diarrhea. The rate of in-hospital mortality was 1.3%.

Conclusions

The PD with SMA first approach combined TMpE for periampullary malignancies was effective in achieving superior oncological statistics (rate of MP R0-resection and number of total resected LNs) with non-inferior short-term outcomes. It is necessary to evaluate survival outcomes with long-term follow-up.

"Five steps four quadrants" modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in laparoscopic pancreaticoduodenectomy

BACKGROUND

Although en bloc dissection of hepatic hilum lymph nodes has many advantages in radical tumor treatment, the feasibility and safety of this approach for laparoscopic pancreaticoduodenectomy (LPD) require further clinical evaluation and investigation.

AIM

To explore the application value of the "five steps four quadrants" modularized en bloc dissection technique for accessing hepatic hilum lymph nodes in LPD patients.

METHODS

A total of 52 patients who underwent LPD via the "five steps four quadrants" modularized en bloc dissection technique for hepatic hilum lymph nodes from April 2021 to July 2023 in our department were analyzed retrospectively. The patients' body mass index (BMI), preoperative laboratory indices, intraoperative variables and postoperative complications were recorded. The relationships between preoperative data and intraoperative lymph node dissection time and blood loss were also analyzed.

RESULTS

Among the 52 patients, 36 were males and 16 were females, and the average age was 62.2 ± 11.0 years. There were 26 patients with pancreatic head cancer, 16 patients with periampullary cancer, and 10 patients with distal bile duct cancer. The BMI was 22.3 ± 3.3 kg/m², and the median total bilirubin (TBIL) concentration was 57.7 (16.0-155.7) µmol/L. All patients successfully underwent the "five steps four quadrants" modularized en bloc dissection technique without lymph node clearance-related complications such as postoperative bleeding or lymphatic leakage. Correlation analysis revealed significant associations between preoperative BMI (r = 0.3581, P = 0.0091), TBIL level (r = 0.2988, P = 0.0341), prothrombin time (r = 0.3018, P = 0.0297) and lymph node dissection time. Moreover, dissection time was significantly correlated with intraoperative blood loss (r = 0.7744, P < 0.0001). Further stratified analysis demonstrated that patients with a preoperative BMI ≥ 21.9 kg/m² and a TIBL concentration ≥ 57.7 μmol/L had significantly longer lymph node dissection times (both P < 0.05).

CONCLUSION

The "five steps four quadrants" modularized en bloc dissection technique for accessing the hepatic hilum lymph node is safe and feasible for LPD. This technique is expected to improve the efficiency of hepatic hilum lymph node dissection and shorten the learning curve; thus, it is worthy of further clinical promotion and application.

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.

Pancreatic head cancer - Current surgery techniques

Pancreatic head cancer is a highly fatal disease. For now, surgery offers the only potential long-term cure albeit with a high risk of complications. However, the progress of surgical technique during the past decade has resulted in 5-year survival approaching 30% after resection and adjuvant chemotherapy. This paper presents current data on the recommended extent of lymphadenectomy, the resection margin, on the definition of resectable and borderline resectable tumors and mesopancreas. Surgical techniques proposed to improve PD are presented: the artery first approach, the uncinate process first, the mesopancreas first approach, the triangle operation, periarterial divestment, and multiorgan resection.

Total laparoscopic pancreaticoduodenectomy with left posterior superior mesenteric artery first-approach and plexus-preserving circumferential lymphadenectomy: step-by-step technique with a surgical case report (with video)

Introduction

Total laparoscopic pancreaticoduodenectomy (tLPD) for cancer of the Vater remains a challenging procedure. Recently, several meta-analyses showed the superior aspects of “superior mesenteric artery (SMA)-first approach,” “systematic mesopancreas dissection,” and “circumferential lymphadenectomy around SMA” in increasing R0 resection rate and reducing postoperative complications including pancreatic fistula and bleeding as well as improving overall survival particularly.

Case presentation

Our patient is a 70-year-old female with a no special medical history, recruited because of jaundice. She was referred for pancreaticoduodenectomy because of a 10-mm-sized mass in distal bile duct referred to as Vater’s tumor. We used 5 trocars, and the patient was placed in a Trendelenburg position. The transverse colon was lifted, the first loop of the jejunum was pulled to the left, and lymph node groups 14th and 15th were removed en bloc and then exposed the SMA from the anterior to the left posterior side from the caudal side to the origin. The first jejunal vessels and the posterior inferior pancreaticoduodenal artery were ligated as well as the extensive mobility of the duodenum and head of the pancreas from the left side. The systematic mesopancreas dissection from the right site of the SMA will be easily and conveniently done afterwards. Histopathological examination of ypT2N1 indicated that 1 of the 22 lymph nodes was positive, which was 1 of 7 LN no. 14. Pathological results showed a Vater adenocarcinoma with all margins being negative.

Conclusions

This technique was safe and effective to perform precise level 2 mesopancreas dissection and complete lymphadenectomy around SMA without dissection of pl-SMA in laparoscopic field.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02730-y.

Current status and perspectives of the future of pancreatic surgery: Establishment of evidence by integration of "art" and "science"

Pancreatic cancer surgery continues to be associated with a high operative morbidity rate, poor long-term survival outcomes, and various challenges in obtaining high-level evidence. Not only is the early postoperative morbidity rate high, but also late morbidity involves lifelong nutritional support for long-term survivors. Due to poor survival outcomes even after curative surgery, pancreatic surgeons have doubts about the role of surgery as the definitive treatment for pancreatic cancer. Additionally, conducting clinical trials to obtain high-level evidence in the field of pancreatic surgery is difficult, and the results have only had a moderate impact on clinical practice due to skepticism regarding their quality. Therefore, quality evidence regarding the extent of resection, mode of approach to dissection, reconstruction methods for pancreatico-enteric anastomosis, determination of resectability, timing of surgery, and the definition of the resection margin is lacking. However, numerous innovative pancreatic surgical procedures have been developed, which may aptly have been called "art" when they were first introduced, regardless of whether they subsequently were supported by scientific evidence. In this review, we provide recent examples of the integration of art and science in the field of pancreatic surgery, which illustrate how the creative ideas of pancreatic surgeons evolved into generally accepted clinical practice. Pancreatic surgeons should be considered "surgical artists," "surgical scientists," and "surgical practitioners." We look forward to more "surgical artists" educating future "surgical artists and scientists" to create a richer "spirit of innovation," leading to a more beautiful integration of art and science in the field of pancreatic surgery.

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.