Optimal Extent of Superior Mesenteric Artery Dissection during Pancreaticoduodenectomy for Pancreatic Cancer: Balancing Surgical and Oncological Safety

Postoperative Refractory Diarrhea After Margin Accentuation of the Superior Mesenteric Artery with Irreversible Electroporation in Pancreaticoduodenectomy

Background: Pancreatic ductal adenocarcinoma (PDAC) presents a challenge due to its poor prognosis. Irreversible electroporation (IRE) shows promise in improving margin clearance and increasing R0 and R1 indirect resection rates. Although IRE is believed to preserve surrounding tissues, this study aimed to assess postoperative refractory diarrhea as a severe complication and challenge the assumption of consistent tissue preservation. Methods: Patients undergoing pancreaticoduodenectomy (PD) with IRE for superior mesenteric artery (SMA) margin accentuation between May 2022 and April 2024 were included. Primary endpoints were diarrhea-related morbidity and mortality; secondary endpoints included R-status, recurrence, and metastases. IRE electrodes were initially positioned circumferentially around the SMA, but this approach was modified to hemi-circumferential placement and applied in six additional patients. Results: All five patients (median age 70, 80% female) in the initial cohort developed secretory diarrhea lasting a median of 6 months (IQR 5-6.5), with a median frequency of 5 stools/day (IQR 5-6.5). Two patients (40%) died due to diarrhea-associated cachexia. In contrast, among the six patients treated with the modified technique, patients' diarrhea resolved within a median of 8 days (IQR 6-10) without need for opioid or advanced antidiarrheal therapy. Conclusions: Circumferential IRE for SMA margin accentuation may damage the superior mesenteric plexus and induce severe, prolonged diarrhea. Hemi-circumferential application may mitigate this risk. Larger studies are required to validate these findings and optimize the use of IRE in PD.

Long-term outcomes of prophylactic right-half dissection of the superior mesenteric artery nerve plexus in pancreatoduodenectomy for pancreatic ductal adenocarcinoma: five-year results from a randomized phase II trial

PURPOSES

In pancreaticoduodenectomy for pancreatic ductal adenocarcinoma (PDAC), Prophylactic right-half dissection of the superior mesenteric artery (SMA) nerve plexus has been attempted in pancreaticoduodenectomy for pancreatic ductal adenocarcinoma. In this study, we evaluated the significance of prophylactic right-half dissection of the SMA nerve plexus by extending the observation period to 5 years.

METHODS

From April 2014 to June 2018, 74 patients with PDAC in the pancreatic head were randomly assigned to either the dissection group, in which the right half of the nerve plexus of the SMA was dissected (n = 37) or the preservation group, in which the nerve plexus of the SMA was completely preserved (n = 37). The 5-year relapse-free survival (RFS), overall survival (OS), and incidence of diarrhea were prospectively compared between groups.

RESULTS

The median RFS (20 vs. 16 months, P = 0.503) and OS (37.0 vs. 30.0 months, P = 0.582) did not differ significantly between the dissection and preservation groups. There was no significant difference in locoregional recurrence (27.0% vs. 37.8%, P = 0.320) or distant metastasis (64.9% vs. 83.0%, P = 0.451). Postoperative diarrhea occurred in 64.9% and 62.2% of the cases in the dissection and preservation groups, respectively (P = 0.809).

CONCLUSION

Prophylactic right half dissection of the SMA nerve plexus did not improve the RFS or OS.

Stapled Arterial Divestment in Surgery for Locally Advanced Pancreatic Cancer

BACKGROUND

Pancreatic adenocarcinoma has a predisposition to invade the neural tissue surrounding the superior mesenteric artery (SMA). Before the advent of neoadjuvant chemotherapy (NAC), any invasion of this tissue was often considered as unresectable disease. Currently, patients who respond favourably to NAC have potentially resectable disease. There is debate over the exact technique of removing this shell of tumour tissue surrounding the SMA, and whether it is comparable to arterial resection and reconstruction.

METHODS

We describe a technique of en bloc arterial divestment in which an endovascular stapler combined with sharp dissection is used to divide the shell of periadventitial SMA tissue.

CONCLUSIONS

In patients with locally advanced disease, the technique of arterial divestment can be safely performed where the tumour is not invading below the external elastic lamina. This allows complete tumour resection without incurring the higher morbidity and mortality associated with SMA resection.

Arterial resection and divestment in pancreatic cancer surgery in the era of multidisciplinary treatment: decadal comparative study

BACKGROUND

The aim of this study was to investigate the feasibility and effectiveness of pancreatectomy with arterial resection/divestment for pancreatic cancer with arterial involvement in the modern era of multidisciplinary treatment.

METHODS

Patients who underwent pancreatectomy with arterial resection/pancreatectomy with arterial divestment for pancreatic cancer with arterial involvement from 2010 to 2021 were retrospectively analysed, and outcomes were compared between the former (2010-2015) and latter interval (2016-2021). Survivals were compared by univariable and multivariable analyses.

RESULTS

Among 203 patients included, 76 underwent pancreatectomy with arterial resection and 127 underwent pancreatectomy with arterial divestment. Compared with the former interval, more patients received preoperative chemotherapy (26.6% (n = 21) versus 95% (n = 118), P < 0.001), and underwent pancreatectomy with arterial resection (30.4% (n = 24) versus 41.9% (n = 52), P = 0.287) in the latter interval. The major morbidity rate and pancreatic fistula decreased in the latter interval (major morbidity rate: P = 0.040; pancreatic fistula: P = 0.006), even among patients undergoing pancreatectomy with arterial resection (major morbidity rate: P = 0.013; pancreatic fistula: P < 0.001). Patients in the latter interval had better overall survival (26.0 versus 48.2 months, P = 0.001), even among patients undergoing pancreatectomy with arterial resection (22.0 versus 45.1 months, P = 0.076).

CONCLUSIONS

Within the context of modern multidisciplinary treatment, radical resection including arterial resection should be justified for patients with pancreatic cancer with arterial involvement, considering the acceptable perioperative risk and prolonged survival.

Mesopancreas dissection level 3 for pancreatic head cancer in combined robotic/open pancreatoduodenectomy: a propensity score-matched study

BACKGROUND

Mesopancreas dissection (MPD) level 3 in combined robotic/open pancreatoduodenectomy (CR/OPD) is technique-demanding. This study aims to clarify the feasibility and justification of MPD level 3.

METHODS

Propensity score matching (PSM) analysis was conducted for 208 patients with pancreatic head cancer undergoing CR/OPD with or without MPD level 3. The comparison focused on surgical and oncological outcomes.

RESULTS

After PSM, each group comprised 86 patients. Surgical outcomes were comparable between these two groups, except longer operation time for MPD level 3 (+), median: 10.5 vs. 9.5 h, p = 0.002. MPD level 3 (+) group exhibited higher lymph node yield, median: 20 vs. 17, p < 0.001, and curative (R0) resection rate, 89.5% vs. 69.8%, p = 0.001, compared to MPD level 3 (-) group. Among the entire cohort, no significant survival difference was observed between the MPD Level 3 (+) and (-) groups. Survival outcome for R0 resection after CR/OPD was notably better than those for R2 resection, 5-year survival: 34.0% vs. 0, p = 0.038. However, within the curative (R0) resection cohort, no survival difference was observed between the MPD level 3 (+) and MPD level 3 (-) groups.

CONCLUSION

MPD level 3 in CR/OPD is technically feasible without increasing the surgical risks but takes one hour extra operating time. Incorporation of MPD level 3 does not confer a survival advantage within the curative (R0) resection cohort. The primary focus should continue to be on achieving curative (R0) resection to maximize the survival benefits for pancreatic head cancer.

Survival Analysis of Conversion Surgery in Borderline Resectable and Locally Advanced Unresectable Pancreatic Ductal Adenocarcinoma Addressing Selection and Immortal Time Bias: A Retrospective Single-Center Study

BACKGROUND

The purpose of this study was to provide a detailed evaluation of the oncological advantages of surgery following neoadjuvant chemotherapy (NAC) for patients with borderline resectable (BR) or unresectable (UR) pancreatic ductal adenocarcinoma (PDAC), with a focus on minimizing biases. Recently, NAC has become the standard care for BR or UR locally advanced (UR-LA) PDAC, however, many studies have assessed survival benefits and favorable variables without consideration for biases, particularly immortal time bias.

PATIENTS AND METHODS

This study included patients diagnosed with BR or UR-LA PDAC at Juntendo University Hospital from 2019 to 2022. To mitigate bias, we applied methods such as propensity score matching (PSM), time-dependent covariate Cox proportional hazard regression analysis (TDC), landmark analysis, and multivariable Cox proportional hazards regression model.

RESULTS

The study analyzed 124 patients, dividing them into a surgery group (n = 57) and a chemotherapy-only group (n = 67). After PSM, there were 21 matched pairs. Survival analysis using TDC analysis showed that the surgery group had significantly better overall survival compared with the chemotherapy-only group in both the entire cohort and the matched pairs. Cox regression analysis of the entire cohort also revealed a similar superiority of surgery, while the landmark analysis showed varying results depending on the landmark setting.

CONCLUSIONS

After careful adjustment for selection and immortal time biases, surgery following NAC appears to significantly extend survival in patients with BR or UR PDAC.

Impact of overweight on patients undergoing laparoscopic pancreaticoduodenectomy: analysis of surgical outcomes in a high-volume center

BACKGROUND

The feasibility and safety of laparoscopic pancreaticoduodenectomy (LPD) in overweight patients is still controversial. This study was designed to analyze the impact of overweight on surgical outcomes in patients undergoing LPD.

METHODS

Data from patients who underwent LPD between January 2018 and July 2022 were analyzed retrospectively. A 1:1 propensity score-matching (PSM) analysis was performed to minimize bias between groups.

RESULTS

A total of 432 patients were enrolled, with a normal weight group (n = 241) and an overweight group (n = 191). After matching, 144 patients were enrolled in each group. The results showed that the incidence of clinically relevant postoperative pancreatic fistula (CR-POPF) and delayed gastric emptying (DGE) was significantly higher in the overweight group compared to the normal weight group (P = 0.036). However, there were no significant differences in perioperative mortality (1.4% vs. 2.1%, P = 0.652) and long-term survival outcomes between malignancy patients with different body mass index (BMI) before and after PSM (all P > 0.05).

CONCLUSIONS

It is safe and feasible for overweight patients to undergo LPD with mortality and long-term survival outcomes comparable to the normal weight group. High-quality prospective randomized controlled trials are still needed.

Identifying suitable candidates for pancreaticoduodenectomy with extended lymphadenectomy for pancreatic ductal adenocarcinoma

BACKGROUND

To evaluate long-term quality of life and survival in pancreatic ductal adenocarcinoma (PDAC) patients after pancreatoduodenectomy with extended lymphadenectomy (PDEL) and identify candidates.

METHODS

Patients with resectable PDAC with ≥1 examined lymph node (LN) during pancreatoduodenectomy (PD), and were divided into the PD with standard lymphadenectomy (PDSL) and PDEL groups. Perioperative data, long-term quality of life and survival were compared, and the prognostic effect of LNs ± in every peripancreatic station were analysed.

RESULTS

Screening 446 PDAC patients, 237 and 126 were included in the PDSL and PDEL groups, respectively. The PDEL group showed a longer operation time, greater intraoperative blood loss, severe diarrhoea, a higher incidence of grade III complications. Notably, the PDEL patients experienced significant relief from low back pain and diarrhoea, with an obvious survival advantage (p = 0.037), especially in patients with preoperative tumor contact with vascular and pathological N0; however, LNs+ in any station (No. 8p, 12, 14, or 16) were associated with a poorer prognosis. The vascular reconstruction, T and N stage were independent risk factors for survival.

CONCLUSION

PDEL can relieve symptoms and prolong the survival of PDAC patients with acceptable complications, and EL should be performed regardless of preoperative LN enlargement.

Radicality and safety of total mesopancreatic excision in pancreatoduodenectomy: a systematic review and meta-analysis

BACKGROUND

Pancreatic head cancer patients who undergo pancreatoduodenectomy (PD) often experience disease recurrence, frequently associated with a positive margin status (R1). Total mesopancreas excision (TMpE) has emerged as a potential approach to increase surgical radicality and minimize locoregional recurrence. However, its effectiveness and safety remain under evaluation.

METHODS

We conducted a systematic review and meta-analysis to synthesize current evidence on TMpE outcomes. A systematic search of MEDLINE, EMBASE, Cochrane, and Web of Science databases was conducted up to March 2024 to identify studies comparing TMpE with standard pancreatoduodenectomy (sPD). The risk ratio (RR) or mean difference (MD) was pooled using a random effects model.

RESULTS

From 452 studies identified, 9 studies with a total of 738 patients were included, with 361 (49%) undergoing TMpE. TMpE significantly improved the R0 resection rate (RR 1.24; 95% CI 1.11-1.38; P < 0.05), reduced blood loss (MD -143.70 ml; 95% CI -247.92, -39.49; P < 0.05), and increased lymph node harvest (MD 7.27 nodes; 95% CI 4.81, 9.73; P < 0.05). No significant differences were observed in hospital stay, postoperative complications, or mortality between TMpE and sPD. TMpE also significantly reduced overall recurrence (RR 0.53; 95% CI 0.35-0.81; P < 0.05) and local recurrence (RR 0.39; 95% CI 0.24-0.63; P < 0.05). Additionally, the risk of pancreatic fistula was lower in the TMpE group (RR 0.66; 95% CI 0.52-0.85; P < 0.05).

CONCLUSION

Total mesopancreas excision significantly increases the R0 resection rate and reduces locoregional recurrence while maintaining an acceptable safety profile when compared with standard pancreatoduodenectomy. Further prospective randomized studies are warranted to determine the optimal surgical approach for total mesopancreatic resection.

Impact of preoperative self-expandable metal stent on benign hepaticojejunostomy anastomotic stricture after pancreaticoduodenectomy

Objectives

Hepaticojejunostomy anastomotic stricture (HJAS) is a serious adverse event of pancreaticoduodenectomy. Preoperative biliary drainage with a self-expandable metal stent (SEMS) is often performed before pancreaticoduodenectomy. The purpose of this study is to evaluate the risk factors and impact of preoperative SEMS placement on developing benign HJAS after pancreaticoduodenectomy.

Methods

We retrospectively analyzed consecutive patients who underwent pancreatoduodenectomy at our institution between July 2014 and June 2020. Risk factors for benign HJAS were identified using univariate and multivariate logistic regression analysis. We also compared outcomes of preoperative biliary drainage using SEMS and non-SEMS.

Results

Of the 626 included patients, benign HJAS occurred in 36 patients (5.8%). The median follow-up time was 36.7 months (interquartile range, 25.4-57.4 months). Multivariate logistic regression analysis revealed that lack of preoperative biliary drainage, preoperative bile duct diameter <5 mm, and former or current smoking were independent predictors of benign HJAS. In the preoperative biliary drainage group, the rate of preoperative bile duct diameter <5 mm was significantly lower in the SEMS group than in the non-SEMS group (2.0% vs. 12.8%, p = 0.04).

Conclusions

Preoperative biliary drainage with SEMS may be useful to maintain bile duct diameter ≥5 mm and to reduce benign HJAS as a result.

Splenic vein tumor thrombosis is a major prognostic factor in distal pancreatic adenocarcinoma

BACKGROUND

The prognostic value of splenic vessel involvement in distal pancreatic adenocarcinoma remains controversial. The aim of the study was to assess its prognostic relevance in a large multicenter cohort.

METHODS

Patients who underwent pancreatosplenectomy for distal pancreatic adenocarcinoma were identified from 5 pancreatic surgical centers. A pathology review of the surgical specimens was performed to assess splenic vessel involvement, defined as invasion of the vessel's adventitia or deeper, and confirm the presence of splenic vein tumor thrombosis. Prognostic factors associated with overall and relapse-free survival were evaluated.

RESULTS

149 patients underwent upfront surgery. Splenic vascular involvement was observed in 69 of them (46.3%). A parietal infiltration of the splenic artery or splenic vein was observed in 26 (17.5%) and 49 patients (32.8%), respectively. A pathologic tumor thrombosis of the splenic vein was identified in 22 patients (14.8%) and associated with larger tumors (>20 mm) (P = .023), more perineural (P = .017), and lymphovascular (P = .002) invasion, and more positive lymph node (P = .001). After a median follow-up of 50.8 months (95% confidence interval: 44.3-57.3), the cumulative 5-year overall and relapse-free survival were 46.2% and 33%, respectively. In multivariate analysis, in addition to lymph node metastasis (hazard ratio = 1.8; 95% confidence interval [1.1-3.1]; P = .023) and perineural invasion (hazard ratio = 3.5; 95% confidence interval [1.3-9.7]; P = .016), presence of splenic vein tumor thrombosis was the only splenic vascular involvement that affected independently the overall survival (HR = 2.3; 95% confidence interval [ 1.3-4.3]; P = .006).

CONCLUSION

In resectable distal pancreatic adenocarcinoma, a pathologic tumor thrombosis of the splenic vein is an independent prognostic factor of overall survival. To define the perioperative oncological strategy, a preoperative evaluation of splenic vessel involvement and thrombosis is needed.

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.

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

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

Unique Biology of Pancreatic Ductal Adenocarcinoma Accompanied by Rapidly Impaired Diabetes: A Favorable Long-Term Survival Following Curative Resection

BACKGROUND

Pancreatic ductal adenocarcinomas (PDACs) are sometimes diagnosed accompanied by rapidly impaired diabetes (PDAC-RID). Although this type of PDAC may have unusual biological features, these features have not been explained.

METHODS

Patients with PDAC who underwent upfront pancreatectomy between 2010 and 2018 were retrospectively reviewed. PDAC-RID was defined as a glycated hemoglobin (HbA1c) value of ≥ 8.0% of newly diagnosed diabetes, and acute exacerbation of previously diagnosed diabetes. Other patients were classified as PDAC with stable glycometabolism (PDAC-SG). Clinicopathological factors, long-term survival rates, and recurrence patterns were evaluated.

RESULTS

Of the 520 enrolled patients, 104 were classified as PDAC-RID and 416 as PDAC-SG. There was no significant difference regarding TNM staging, resectability, or adjuvant chemotherapy rate between the groups. However, 5-years cancer-specific survival (CSS) was significantly higher in the PDAC-RID group than in the PDAC-SG group (45.3% vs. 31.1%; p = 0.02). This survival difference was highlighted in relatively early-stage PDAC (≤ pT2N1) (CSS: 60.8% vs. 43.6%; p = 0.01), but the difference was not significant for advanced-stage PDAC. A multivariate analysis of early-stage PDAC showed that PDAC-SG was an independent risk factor of shorter CSS (hazard ratio 1.76; p = 0.02). The hematogenous metastatic rate in early-stage PDAC was lower in the PDAC-RID group than in the PDAC-SG group (18.3% vs. 35.8%; p = 0.01).

CONCLUSIONS

PDAC-RID showed a favorable long-term survival rate after curative resection with low hematogenous metastases, which may be due to its unique biology.

Functional sequelae after pancreatic resection for cancer

The morbidity and mortality of pancreatic cancer surgery has seen substantial improvement due to the standardization of surgical techniques, the optimization of perioperative multidisciplinary management and the organization of specialized care systems. The identification and treatment of postoperative functional and nutritional sequelae have thereby become major issues in patients who undergo pancreatic surgery. This review addresses the functional sequelae of pancreatic resection for cancerous and pre-cancerous lesions (excluding chronic pancreatitis). Its aim is to specify the prevalence and severity of sequelae according to the type of pancreatic resection and to document, where appropriate, the therapeutic management. Exocrine pancreatic insufficiency (ExPI) is observed in nearly one out of three patients at one year after surgery, and endocrine pancreatic insufficiency (EnPI) is present in one out of five patients after pancreatoduodenectomy (PD) and one out of three patients after distal pancreatectomy (DP). In addition, digestive functional disorders may appear, such as delayed gastric emptying (DGE), which affects 10 to 45% of patients after PD and nearly 8% after DP. Beyond these functional sequelae, pancreatic surgery can also induce nutritional and vitamin deficiencies secondary to a lack of uptake for certain vitamins or to the loss of absorption site in the duodenum. In addition to the treatment of ExPI with oral pancreatic enzymes, nutritional management is based on a high-calorie, high-protein diet with normal lipid intake in frequent small feedings, combined with vitamin supplementation adapted to monitored deficiencies. Better knowledge of the functional consequences of pancreatic cancer surgery can improve the overall management of patients.

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

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

Laparoscopic dissection around the superior mesenteric artery by left posterior approach during pancreaticoduodenectomy

BACKGROUND

In pancreaticoduodenectomy (PD), the approach to superior mesenteric artery (SMA) is a critical process that supports adequate surgical margins and radicality for pancreatic tumors. In most of the reports on laparoscopic PD, the right-sided approach in which the jejunum is pulled out to the right side for peri-SMA dissection is used, since the left side of the SMA is difficult to dissect, and the only way to do this is to dissect the vein first.

METHODS

We devised a method to simplify and safely perform peri-SMA dissection by reversing the process, starting from the left side of the SMA. The first step involves the mobilization of the pancreatic head, which allows for rotation around the SMA. The second step involves the dissection of the left side of the SMA and transection of the jejunum. The key point is to change the incision line between the anterior and posterior mesojejunum. The third process includes the inferior pancreatoduodenal artery (IPDA) and first jejunal artery (J1A) dissection, which can be easily performed from the left side because the SMA rotates by simply continuing the dissection along the previously exposed SMA, and the IPDA/J1A are safely dissected at the root because they are drawn to the left side. The remaining processes are performed on the right side.

RESULTS

This method was performed in 16 cases, and in most cases IPDA/J1A were divided from the left side.

CONCLUSION

The technique for SMA dissection from the left posterior side was described with illustrations and video. Our method allows safe oncologic dissection around SMA avoiding anatomical misorientation during laparoscopic PD.

New approach of circumferential lymph node dissection around the superior mesenteric artery for pancreatic cancer during pancreaticoduodenectomy (with video)

PURPOSE

Various approaches have been reported for the resection of the nervous and lymphatic tissues around the superior mesenteric artery (SMA) during pancreaticoduodenectomy (PD) for pancreatic cancer. We developed a new procedure for circumferential lymph node dissection around the SMA to minimize local recurrence.

METHODS

We included 24 patients who underwent PD with circumferential lymph node dissection around the SMA (circumferential dissection) and 94 patients who underwent classical mesopancreatic dissection (classical dissection) between 2019 and 2021. The technical details of this new method are described in the figures and videos, and the clinical characteristics and outcomes of this technique were compared with those of classical dissection.

RESULTS

The median follow-up durations in the circumferential and classical dissection groups were 39 and 36 months, respectively. The patients' characteristics, including tumor resectability, preoperative and adjuvant chemotherapy rates, postoperative complication rates, and tumor stage, were similar between the two groups. No differences were observed in recurrence-free survival and overall survival between the two groups; however, the classical dissection group tended to have more local recurrences than the circumferential dissection group (8.3% vs. 33.3%, P = 0.168). Although no case of nodular-type recurrence after circumferential dissection was observed, 61.1% of local recurrences after classical dissection were of the nodular-type, and 36.4% were located on the left side of the SMA.

CONCLUSIONS

Performing circumferential lymph node dissection around the SMA during PD can be conducted safely with minimal risks of local recurrence and may enhance the completeness of local resection.

Total Superior Mesenteric Artery Nerve Plexus Preservation During Pancreaticoduodenectomy for Pancreatic Cancer

BACKGROUND

Superior mesenteric artery (SMA) nerve plexus (PLsma) dissection has been performed to achieve R0 resection in pancreaticoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC) in high-volume centers. However, full-extent PLsma preservation in PD is employed in our institution. The feasibility of the PLsma preservation strategy was investigated.

METHODS

Between January 2010 and December 2020, 156 patients underwent PLsma preservation PD for PDAC at our institution. Of these, 118 patients had resectable PDAC (R group) and 38 patients had borderline resectable artery (BR-A group). Clinical and oncological outcomes focusing on local recurrence, patient prognoses, and morbidities (including postoperative refractory diarrhea) were retrospectively analyzed and our postoperative outcomes were compared with those of other institutions.

RESULTS

Pathological R0 resection by PLsma preservation PD was achieved in 96 R group patients (81.4%) and 27 BR-A group patients (71.1%). The median postoperative hospital stay was 15.0 days in both groups. Local site-only recurrence was observed in 10.2% (12/118) of R-group and 10.5% (4/38) of BR-A-group patients, whereas distant site-only recurrence occurred in 21.2% (25/118) of R-group and 28.9% (11/38) of BR-A-group patients. Median survival times were 64.3 months (R group) and 35.4 months (BR-A group, p = 0.07). Median disease-free survival (DFS) times were 31.0 months (R group) and 12.0 months (BR-A group). No diarrhea requiring opioids was observed in either group. These results were equal or superior to those of PLsma dissection PD in other institutions.

CONCLUSIONS

PLsma preservation in PD was feasible compared to PLsma dissection in recurrence and overall survival.

Impact of sarcopenia on S1 adjuvant chemotherapy and prognosis in pancreatic cancer patients

Although the importance of adjuvant chemotherapy (AC) has been recognized in pancreatic cancer (PC) patients, there are few studies to address the underlying mechanisms of failure to complete AC. This study aims to investigate the relationship between nutritional state represented by sarcopenia and failure to complete AC in patients after curative-intent surgery for PC. This study included 110 patients who underwent pancreaticoduodenectomy for potentially resectable pancreatic cancers with intention of adjuvant S-1. Sarcopenia was defined using the psoas muscle mass index with cutoff values of 6.36 cm2/m2 for men and 3.92 cm2/m2 for women, which were calculated with a 3-D volumetric software. The relation between sarcopenia and successful AC and long-term survival were investigated. Twenty-nine (26%) patients were diagnosed as having sarcopenia (Sarcopenia group). Sarcopenia group comprised significantly older patients than Non-sarcopenia group (72 vs. 67 years old, p = 0.0087). AC was successfully completed in 14 patients (48%) in Sarcopenia group compared to 72 patients (89%) in Non-sarcopenia group (p < 0.0001). Multivariate analysis identified age ≥ 70 years and sarcopenia as significant risk factors for failure of AC. Among patients ≥ 70 years old, rate of successful AC was significantly higher in sarcopenia groups than non-sarcopenia group (17% vs. 78%, p < 0.001). In conclusions, age and sarcopenia were critical risk factors for the failure of 6 months of adjuvant chemotherapy. Among elderly patients, sarcopenia can predict the poor success rate of AC.

"Conversion surgery" for locally advanced pancreatic cancer: A position paper by the study group at the joint meeting of the International Association of Pancreatology (IAP) & Japan Pancreas Society (JPS) 2022

Locally advanced pancreatic cancer (LAPC), which progresses locally and surrounds major vessels, has historically been deemed unresectable. Surgery alone failed to provide curative resection and improve overall survival. With the advancements in treatment, reports have shown favorable results in LAPC after undergoing successful chemotherapy therapy or chemoradiation therapy followed by surgical resection, so-called "conversion surgery", at experienced high-volume centers. However, recognizing significant regional and institutional disparities in the management of LAPC, an international consensus meeting on conversion surgery for LAPC was held during the Joint Congress of the 26th Meeting of the International Association of Pancreatology (IAP) and the 53rd Annual Meeting of Japan Pancreas Society (JPS) in Kyoto in July 2022. During the meeting, presenters reported the current best multidisciplinary practices for LAPC, including preoperative modalities, best systemic treatment regimens and durations, procedures of conversion surgery with or without vascular resections, biomarkers, and genetic studies. It was unanimously agreed among the experts in this meeting that "cancer biology is surpassing locoregional anatomical resectability" in the era of effective multiagent treatment. The biology of pancreatic cancer has yet to be further elucidated, and we believe it is essential to improve the treatment outcomes of LAPC patients through continued efforts from each institution and more international collaboration. This article summarizes the agreement during the discussion amongst the experts in the meeting. We hope that this will serve as a foundation for future international collaboration and recommendations for future guidelines.

Clinical Efficacy of Neoadjuvant Chemotherapy with Gemcitabine plus S-1 for Resectable Pancreatic Ductal Adenocarcinoma Compared with Upfront Surgery

BACKGROUND

The efficacy of neoadjuvant chemotherapy with gemcitabine plus S-1 (NAC-GS) in the prognosis of patients with resectable pancreatic ductal adenocarcinoma (PDAC) has been reported. NAC-GS is now assumed to be a standard regimen for resectable PDAC in Japan. However, the reason for this improvement in prognosis remains unclear.

METHODS

In 2019, we introduced NAC-GS for resectable PDAC. From 2015 to 2021, 340 patients were diagnosed with resectable PDAC (anatomical and biological [carbohydrate antigen (CA) 19-9 < 500 U/mL]) and were divided according to the treatment period (upfront surgery [UPS] group, 2015-2019, n = 241; NAC-GS group, 2019-2021, n = 80). We used "intention-to-treat" analysis to compare the clinical outcomes of NAC-GS to those of UPS.

RESULTS

Of the 80 patients with NAC-GS, 75 (93.8%) completed two cycles of NAC-GS, and the resection rate of the NAC-GS group was comparable to that of the UPS group (92.5 vs. 91.3%, P = 0.73). The R0 resection rate was significantly higher in the NAC-GS group than in the UPS group (91.3 vs. 82.6%, P = 0.04), even though the surgical burden was smaller. Progression-free survival tended to be better (hazard ratio [HR] = 0.70, P = 0.06), and overall survival was significantly better in the NAC-GS group than in the UPS group (HR 0.55, P = 0.02).

CONCLUSIONS

NAC-GS provided improvements in microscopic invasion leading to a high R0 rate and smooth administration and completion of adjuvant therapy, which might lead to an improved prognosis in patients with resectable PDAC.

Technical options in surgery for artery-involving pancreatic cancer: Invasion depth matters

Background

The artery involvement explains the majority of primary unresectability of non-metastatic pancreatic cancer patients and both arterial resection and artery-sparing dissection techniques are utilized in curative-intent pancreatectomies for artery-involving pancreatic cancer (ai-PC) patients.

Methods

This narrative review summarized the history of resectability evaluation for ai-PC and attempted to interpret its current pitfalls that led to the divergence of resectability prediction and surgical exploration, with a focus on the rationale and the surgical outcomes of the sub-adventitial divestment technique.

Results

The circumferential involvement of artery by tumor currently defined the resectability of ai-PC but insufficient to preclude laparotomy with curative intent. The reasons behind could be: 1. The radiographic involvement of tumor to arterial circumference was not necessarily resulted in histopathological artery wall invasion; 2. the developed surgical techniques facilitated radical resection, better perioperative safety as well as oncological benefit. The feasibility of periadventitial dissection, sub-adventitial divestment and other artery-sparing techniques for ai-PC depended on the tumor invasion depth to the artery, i.e., whether the external elastic lamina (EEL) was invaded demonstrating a hallmark plane for sub-adventitial dissections. These techniques were reported to be complicated with preferable surgical outcomes comparing to arterial resection combined pancreatectomies, while the arterial resection combined pancreatectomies were considered performed in patients with more advanced disease.

Conclusions

Adequate preoperative imaging modalities with which to evaluate the tumor invasion depth to the artery are to be developed. Survival benefits after these techniques remain to be proven, with more and higher-level clinical evidence needed.

Key message

The current resectability evaluation criteria, which were based on radiographic circumferential involvement of the artery by tumor, was insufficient to preclude curative-intent pancreatectomies for artery-involving pancreatic cancer patients. With oncological benefit to be further proven, periarterial dissection and arterial resection have different but overlapping indications, and predicting the tumor invasion depth in major arteries was critical for surgical planning.

Diagnosis and management of postpancreatectomy hemorrhage: A single-center experience of consecutive 1,096 pancreatoduodenectomies

BACKGROUND/OBJECTIVES

This study aimed to assess the outcomes and characteristics of post-pancreatectomy hemorrhage (PPH) in over 1000 patients who underwent pancreatoduodenectomy (PD) at a high-volume hepatopancreaticobiliary center.

METHODS

This retrospective study analyzed consecutive patients who underwent PD from 2010 through 2021. PPH was diagnosed and managed using our algorithm based on timing of onset and location of hemorrhage.

RESULTS

Of 1096 patients who underwent PD, 33 patients (3.0%) had PPH; incidence of in-hospital and 90-day mortality relevant to PPH were one patient (3.0%) and zero patients, respectively. Early (≤24 h after surgery) and late (>24 h) PPH affected 9 patients and 24 patients, respectively; 16 patients experienced late-extraluminal PPH. The incidence of postoperative pancreatic fistula (p < 0.001), abdominal infection (p < 0.001), highest values of drain fluid amylase (DFA) within 3 days, and highest value of C-reactive protein (CRP) within 3 days after surgery (DFA: p < 0.001) (CRP: p = 0.010) were significantly higher in the late-extraluminal-PPH group. The highest values of DFA≥10000U/l (p = 0.022), CRP≥15 mg/dl (p < 0.001), and incidence of abdominal infection (p = 0.004) were identified as independent risk factors for PPH in the multivariate analysis. Although the hospital stay was significantly longer in the late-extraluminal-PPH group (p < 0.001), discharge to patient's home (p = 0.751) and readmission rate within 30-day (p = 0.765) and 90-day (p = 0.062) did not differ between groups.

CONCLUSIONS

Standardized management of PPH according to the onset and source of hemorrhage minimizes the incidence of serious deterioration and mortality. High-risk patients with PPH can be predicted based on the DFA values, CRP levels, and incidence of abdominal infections.

Analysis of prognostic factors for borderline resectable pancreatic cancer after neoadjuvant chemotherapy: the importance of CA19-9 decrease in patients with elevated pre-chemotherapy CA19-9 levels

BACKGROUND

Neoadjuvant chemotherapy (NAC) is widely used to treat borderline resectable pancreatic cancer. This study aimed to evaluate the serum carbohydrate antigen (CA)19-9 response, in association with survival, after four cycles of NAC-gemcitabine plus nab-paclitaxel.

METHODS

From 2015 to 2018, patients with borderline resectable pancreatic cancer were treated with NAC. Patients were stratified into two groups after excluding CA19-9 non-secretor: Group L (CA19-9 ≥2 and ≤500 U/mL) and Group H (CA19-9 >500 U/mL). The CA19-9 decrease during NAC was evaluated as a response of NAC and was assessed in association with survival concomitant with other prognosis factors.

RESULTS

Eighty-seven patients were evaluated (Group L: n = 43, Group H: n = 44). In intention-to-treat-based analysis, Group L exhibited significantly better progression-free survival (PFS) than Group H (median PFS: 24 vs 14months). In resection cohort, no correlation was detected between the CA19-9 decrease and survival in Group L. In Group H, the CA19-9 decrease ≤80% was associated with unfavorable survival in multivariate analysis [Hazard ratio: 4.738 (P = 0.007)].

CONCLUSION

In patients with pre-treatment CA19-9 >500 U/mL, the CA19-9 decrease ≤80% was strongly associated with poor survival and new strategy should be reconsidered for these patients.

Quality of superior mesenteric and hepatic artery dissection in robotic pancreatoduodenectomy for pancreatic cancer

This video manuscript by Ikoma and colleagues demonstrates their approach to the superior mesenteric artery and hepatic artery periadventitial dissection. The quality of superior mesenteric artery and hepatic artery dissections should be maintained in robotic pancreatoduodenectomy when performed for pancreatic cancer, to provide the best possible oncological outcomes.

Surgical Strategies to Dissect around the Superior Mesenteric Artery in Robotic Pancreatoduodenectomy

The concept of the superior mesenteric artery (SMA)-first approach has been widely accepted in pancreatoduodenectomy. However, few studies have reported surgical approaches to the SMA in robotic pancreatoduodenectomy (RPD). Herein, we present our surgical strategies to dissect around the SMA in RPD. Among the various approaches, our standard protocol for RPD included the right approach to the SMA, which can result in complete tumor resection in most cases. In patients with malignant diseases requiring lymphadenectomy around the SMA, we developed a novel approach by combining the left and right approaches in RPD. Using this approach, circumferential dissection around the SMA can be achieved through both the left and right sides. This approach can also be helpful in patients with obesity or intra-abdominal adhesions. The present study summarizes the advantages and disadvantages of both the approaches during RPD. To perform RPD safely, surgeons should understand the different surgical approaches and select the best approach or a combination of different approaches, depending on demographic, anatomical, and oncological factors.

Evaluation of local recurrence after pancreaticoduodenectomy for borderline resectable pancreatic head cancer with neoadjuvant chemotherapy: Can the resection level change after chemotherapy?

BACKGROUND

Neoadjuvant treatment has significant survival benefits for patients with pancreatic cancer. However, local recurrence remains a serious issue, even after neoadjuvant treatment. This study investigated local recurrence after pancreaticoduodenectomy and determined the optimal resection level after neoadjuvant treatment.

METHODS

This retrospective study analyzed consecutive patients who underwent pancreaticoduodenectomy for borderline resectable pancreatic cancer after 4 cycles of neoadjuvant treatment-gemcitabine plus nab-paclitaxel between April 2015 and March 2020. Patients with borderline resectable-artery pancreatic cancer were classified according to the dissection level around the artery: level 3 group, hemi-, or whole circumferential arterial nerve plexus was dissected; and level 2 group, the nerve plexus was preserved.

RESULTS

Fifty-six patients with borderline resectable-artery pancreatic cancer underwent pancreaticoduodenectomy after neoadjuvant treatment (level 3 group, n = 40; level 2 group, n = 16). The resection level in the level 2 group was changed based on post-neoadjuvant treatment computed tomography images or intraoperative frozen section diagnosis. The overall and local recurrence rates were significantly higher in the level 2 group than in the level 3 group (overall recurrence, 93.8% vs 70.0%; P = .037) (local recurrence, 50.0% vs 5.0%; P < .001). Ten patients experienced local recurrence, of which 8 belonged to the level 2 group. Among them, 4 patients were confirmed as cancer-negative by surgical margin analysis or intraoperative frozen section diagnosis but experienced recurrence around the arteries.

CONCLUSION

For treating borderline resectable-artery pancreatic cancer, changing the resection level based on post-neoadjuvant treatment computed tomography images increased the risk of local recurrence. All patients with borderline resectable-artery should undergo level 3 dissection, regardless of the response to neoadjuvant treatment.

Impact of resection margin status on survival after operation for pancreatic head cancer with extrapancreatic nerve plexus invasion

BACKGROUND

Extrapancreatic nerve plexus (PL) invasion of pancreatic ductal adenocarcinoma (PDAC) is an important factor for determining resectability and surgical method. We sought to clarify the characteristics of PDAC with PL invasion and clinical impact of the resection margin status on prognosis for PDAC with PL invasion.

METHODS

A total of 242 patients with pancreatic head cancer who underwent pancreatectomy were evaluated. Clinicopathological data and patient survival were analyzed.

RESULTS

Pathological PL invasion was observed in 68 patients (28.1%). Patients with PL invasion had significantly shorter disease-free survival (DFS) and showed trends toward worse overall survival (OS) than those without PL invasion. While multivariate analysis revealed that PL invasion was not an independent prognostic factor, PL invasion was associated with extensive venous invasion and a high percentage of lymph node metastases, both of which were independent factors affecting DFS and OS. Among patients with PL invasion, there was no significant difference in DFS and OS between the R0 and R1 resection groups.

CONCLUSIONS

PL invasion is a common pathological feature of aggressive PDAC with high propensity for invasiveness and metastatic potential. The microscopic resection margin status may not affect the survival of pancreatic head cancer patients with PL invasion.

Anatomy of the neural fibers at the superior mesenteric artery-a cadaver study

PURPOSE

Most surgeons perform right-sided semicircular clearance of the superior mesenteric artery (SMA) nerve plexus for pancreatic head carcinoma, presuming a linear course of the SMA nerve fibers. The hypothesis was that the SMA nerve plexus fibers follow a non-linear course, and the goal of the present study was to assess the neural fibers distribution along the SMA.

METHODS

The course of neural fibers along the retropancreatic and suprapancreatic SMA was assessed in 7 cadavers.

RESULTS

In the retropancreatic course of the vessel, the main nerve cords branch and form a large number of finer nerve branches performing an anti-clockwise rotation of slightly less than 90° around the SMA. Finer nerve branches are located rather close to the vessel, while the main nerve cords are localized in the loose connective tissue of the peripheral parts of the vascular sheath. Nerve fibers around the suprapancreatic SMA run as two main nerve cords framing the artery on the right lateral-ventral and the left lateral to lateral-dorsal side.

CONCLUSION

The rotation of the nerve fiber around the SMA indicates that a more radical resection of at least 180° of neural tissue around the SMA might be required to achieve tumor clearance in pancreatic cancer with perineural invasion at the uncinate margin.

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.

Optimizing Indications for Conversion Surgery Based on Analysis of 454 Consecutive Japanese Cases with Unresectable Pancreatic Cancer Who Received Modified FOLFIRINOX or Gemcitabine Plus Nab-paclitaxel: A Single-Center Retrospective Study

BACKGROUND

The prognosis of initially unresectable pancreatic cancer (UR-PC) has improved since the introduction of FOLFIRINOX (FFX) or gemcitabine plus nab-paclitaxel (GNP) treatment. Nonetheless, the indications and optimal timing for conversion to resection remain unclear for UR-PC. The aim of this study is to evaluate the characteristics of cases with initially UR-PC who received modified FFX or GNP treatment.

METHODS

This retrospective study reviewed 454 consecutive Japanese UR-PC cases who received modified FFX/GNP treatment. Cases were categorized according to resection status, and overall survival (OS) was evaluated using a multivariable prognostic scoring model (0-4 points, higher score indicating more favorable prognostic factors).

RESULTS

The overall resection rate was 16% for locally advanced UR-PC (UR-LA) and 5% for metastatic UR-PC (UR-M). The resection group had better OS than the nonresection group (median OS time: not reached versus 13.0 months, P < 0.001). The independent prognostic factors were normalized CA19-9 concentration, modified Glasgow prognostic score of 0, tumor shrinkage after chemotherapy, chemotherapy duration ≥ 8 months, and resection. Cases were grouped according to their prognostic score, and the results suggested that candidates for resection might have prognostic scores of 4 points in UR-M cases or 2-4 points in UR-LA cases.

CONCLUSIONS

Stratification according to prognostic score was useful in predicting the outcomes of UR-PC cases and may aid in identifying cases who might benefit from surgical treatment after responding to chemotherapy.

Reconstructing topography and extent of injury to the superior mesenteric artery plexus in right colectomy with extended D3 mesenterectomy: a composite multimodal 3-dimensional analysis

Background

Superior mesenteric artery plexus (SMAP) injury is reported to cause postoperative intractable diarrhea after pancreatic/colonic surgery with extended lymphadenectomy. This study aims to describe the SMAP microanatomy and extent of injury after right colectomy with extended D3 mesenterectomy for cancer.

Methods

Three groups (I) anatomical dissection, (II) postmortem histology, and (III) surgical specimen histology were included. Nerve count and area were compared between groups II and III and paravascular sheath thickness between groups I and II. 3D models were generated through 3D histology, nanoCT scanning, and finally through 3D printing.

Results

A total of 21 specimens were included as follows: Group (I): 5 (3 females, 80–93 years), the SMAP is a complex mesh surrounding the superior mesenteric artery (SMA), branching out, following peripheral arteries and intertwining between them, (II): 7 (5 females, 71–86 years), nerve count: 53 ± 12.42 (38–68), and area: 1.84 ± 0.50 mm2 (1.16–2.29), and (III): 9 (5 females, 55–69 years), nerve count: 31.6 ± 6.74 (range 23–43), and area: 0.889 ± 0.45 mm2 (range 0.479–1.668). SMAP transection injury is 59% of nerve count and 48% of nerve area at middle colic artery origin level. The median values of paravascular sheath thickness decreased caudally from 2.05 to 1.04 mm (anatomical dissection) and from 2.65 to 1.17 mm (postmortem histology). 3D histology models present nerve fibers exclusively within the paravascular sheath, and lymph nodes were observed only outside. NanoCT-derived models reveal oblique nerve fiber trajectories with inclinations between 35° and 55°. Two 3D-printed models of the SMAP were also achieved in a 1:2 scale.

Conclusion

SMAP surrounds the SMA and branches within the paravascular sheath, while bowel lymph nodes and vessels lie outside. Extent of SMAP injury on histological slides (transection only) was 48% nerve area and 59% nerve count. The 35°–55° inclination range of SMAP nerves possibly imply an even larger injury when plexus excision is performed (lymphadenectomy). Reasons for later improvement of bowel function in these patients can lie in the interarterial nerve fibers between SMA branches.

The TRIANGLE operation for pancreatic head and body cancers: early postoperative outcomes

BACKGROUND

Surgical resection is the mainstay of potential cure for patients with pancreatic cancer, however, local recurrence is frequent. Previously, we have described an extended resection technique for pancreatoduodenectomy aiming at a radical resection of the nerve and lymphatic tissue between celiac artery, superior mesenteric artery and mesenteric-portal axis (TRIANGLE operation). Until now, data on postoperative outcome have not been reported, yet.

METHODS

Patients who underwent either partial (PD) or total pancreatoduodenectomy (TP) applying the TRIANGLE procedure were identified. These cohorts were compared to matched historic cohorts with standard resections.

RESULTS

Overall, 330 patients were analysed (PD_TRIANGLE and PD_STANDARD, each n = 108; TP_TRIANGLE and TP_STANDARD, each n = 57). More lymph nodes were harvested in TRIANGLE compared to standard resection (PD: 27.5 (21-35) versus 31.5 (24-40); P = 0.0187, TP: 33 (28-49) versus 44 (29-53); P = 0.3174) and the rate of tumour positive resections margins, R1(direct), dropped. Duration of operation was significantly longer and blood loss higher. Postoperative mortality and complications did not differ significantly.

CONCLUSION

Pancreatoduodenectomy according to the TRIANGLE protocol can be performed without increased morbidity and mortality at a high-volume centre. Long-term survival and quality of life need to be investigated in prospective clinical trials with adequate sample size.

Prediction of Recurrence Pattern of Pancreatic Cancer Post-Pancreatic Surgery Using Histology-Based Supervised Machine Learning Algorithms: A Single-Center Retrospective Study

BACKGROUND

Patients with pancreatic cancer (PC) have poor prognosis and a high incidence of recurrence. Since further treatment is applicable for specific recurrent events, it is important to predict recurrence patterns after surgery. This study aimed to identify and predict early and late recurrence patterns of PC using a histology-based machine learning model.

PATIENTS AND METHODS

Patients who underwent upfront curative surgery for PC between 2001 and 2014 were included. The timing of recurrence and prognosis of each first recurrence site were examined. A histology-based supervised machine learning method, which combined convolutional neural networks and random forest, was used to predict the recurrence and respective sites of metastasis. Accuracy was evaluated using area under the receiver operating characteristic curve (AUC).

RESULTS

In total, 524 patients were included. Recurrence in the liver accounted for 47.8% of all recurrence events in the first year after surgery. Meanwhile, recurrence in the lung occurred later and could become apparent more than 5 years post-surgery, with indications for further surgery. In terms of substantial distant organ metastases, liver and lung metastases were identified as representative early and late recurrence events. The predictive AUCs of the machine learning model for training and test data were 1.000 and 0.861, respectively, and for predicting nonrecurrence were 1.000 for both.

CONCLUSIONS

We identified the liver and lung as early and late recurrence sites, which could be distinguished with high probability using a machine learning model. Prediction of recurrence sites using this model may be useful for further treatment of patients with PC.

Diagnostic Accuracy of CT for Evaluating Circumferential Resection Margin Status in Resectable or Borderline Resectable Pancreatic Head Cancer: A Prospective Study Using Axially Sliced Surgical Pathologic Correlation

OBJECTIVE

CT plays a central role in determining the resectability of pancreatic cancer, which directs the use of neoadjuvant therapy. This study aimed to assess the diagnostic accuracy of CT in predicting circumferential resection margin (CRM) involvement in patients with resectable or borderline resectable pancreatic head cancer.

MATERIALS AND METHODS

Seventy-seven patients who were scheduled for upfront surgery for resectable or borderline resectable pancreatic head cancer were prospectively enrolled, and 75 patients (38 male and 37 female; mean age ± standard deviation, 68 ± 11 years) were finally analyzed. The CRM status was evaluated separately for the superior mesenteric artery (SMA) and posterior and superior mesenteric vein/portal vein (SMV/PV) margins. Three independent radiologists reviewed the preoperative CT images and evaluated the resection margin status. The reference standard for CRM status was pathologic examination of pancreaticoduodenectomy specimens in an axial plane perpendicular to the axis of the second portion of the duodenum. The diagnostic accuracy of CT was assessed for overall CRM involvement, defined as involvement of the SMA or posterior margins (per-patient analysis), and involvement of each of the three resection margins (per-margin analysis). The data were pooled using a crossed random effects model.

RESULTS

Forty patients had pathologically confirmed overall CRM involvement in pancreatic cancer, while CRM involvement was not seen in 35 patients. For overall CRM involvement, the pooled sensitivity and specificity were 15% (95% confidence interval: 7%-49%) and 99% (96%-100%), respectively. For each of the resection margins, the pooled sensitivity and specificity were 14% (9%-54%) and 99% (38%-100%) for the SMA margin, 12% (8%-46%) and 99% (97%-100%) for the posterior margin; and 37% (29%-53%) and 96% (31%-100%) for the SMV/PV margin, respectively.

CONCLUSION

CT showed very high specificity but low sensitivity in predicting pathological CRM involvement in pancreatic cancer.

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.

Diagnosis of celiac artery stenosis using multidetector computed tomography and evaluation of the collateral arteries within the mesopancreas of patients undergoing pancreaticoduodenectomy

INTRODUCTION

Celiac artery (CA) stenosis (CAS), caused by various factors, is often asymptomatic because collateral blood flow from the superior mesenteric artery supplies the CA outflow region. The purpose of this study was to investigate the usefulness of multidetector computed tomography (MDCT) for diagnosing CAS and associated collateral artery formation, and elucidating the effect of CAS on the numbers and diameters of the arteries within the mesopancreas.

MATERIALS AND METHODS

We investigated 106 patients who underwent contrast-enhanced MDCT, before pancreaticoduodenectomy, between January 2015 and September 2019. MDCT was used to determine the percentage stenosis of the CAs; patients were classified into CAS (-) (0-29% stenosis) and CAS (+) (30-100% stenosis) groups. The dissection lines of the mesopancreas were classed as Level I or II, and the numbers and diameters of the arteries along each dissection line were counted and measured.

RESULTS

There were 27 CAS (+) patients and 79 CAS (-) patients. In the CAS (+) group there were more arteries and they had larger diameters than those in the CAS (-) group, at both Levels I and II. There were significantly more arteries when the CA stenosis was ≥30% and they had larger diameters when the stenosis was ≥50%.

CONCLUSIONS

MDCT is useful for diagnosing CAS, and CAS is associated with larger numbers and diameters of the arteries within the mesopancreas.

Robotic pancreaticoduodenectomy for pancreatic head cancer and periampullary lesions

Pancreaticoduodenectomy, so-called "Whipple operation," is a time-consuming and technically demanding complex operation. Traditionally, this procedure has been performed most usually by open approach, which results in a large and painful wound. With the introduction of laparoscopic and robotic surgery, minimally invasive surgery (MIS) has emerged as a worldwide trend to improve wound cosmesis and to minimize wound pain. Although MIS for pancreaticoduodenectomy has also been attempted at some centers, the role of MIS, either robotic or laparoscopic approach, has not been well-established for complex pancreaticoduodenectomy. Given that laparoscopic pancreaticoduodenectomy has been limited by its technical complexity and the high level of advanced laparoscopic skills required for pancreatic reconstruction, a robotic surgical system is introduced to overcome several limitations related to the laparoscopic approach. Providing high-quality three-dimensional (3-D) vision, high optical magnification, articulation of robotic instruments, greater precision with suture targeting, and elimination of surgeon tremor, robotic surgical systems innovatively perform more delicate and complex procedures involving extensive dissection and suturing techniques such as pancreaticoduodenectomy. Although associated with longer operative time, robotic pancreaticoduodenectomy (RPD) has been claimed to have the benefits of less delayed gastric emptying, less blood loss, shorter length of postoperative stay, and lower wound infection rate, as compared with the traditional open pancreaticoduodenectomy (OPD). Moreover, RPD seems to be not only technically feasible but also justified without compromising the survival outcomes for pancreatic head and ampullary adenocarcinomas. Therefore, RPD could be recommended not only to surgeons but also to patients in terms of surgical feasibility, surgical outcomes, and patient satisfaction.

Comparison of perioperative outcomes in pancreatic head cancer patients following either a laparoscopic or open pancreaticoduodenectomy with a superior mesenteric artery first approach

BACKGROUNDS/AIMS

A superior mesenteric artery first approach (SFA) technique can improve the complete resection rate. It can be used to determine whether an operation can be performed by invading the superior mesenteric artery before performing a pancreatic transection in patients with pancreatic ductal adenocarcinoma (PDAC). The aim of this study was to compare perioperative outcomes between laparoscopic and open SFA for PDAC.

METHODS

Between January 2017 and August 2019, consecutive patients who underwent laparoscopic and open pancreaticoduodenectomy (PD) for PDAC using SFA procedures were included and compared between laparoscopic and open procedures.

RESULTS

Fourteen and 83 patients underwent laparoscopic and open surgeries, respectively. In perioperative outcomes, there were no significant differences in the amount of intraoperative blood loss or transfusion rate between the two groups. In the laparoscopic group, the operation time was longer with less patients showing wound infection. R0 resection rate and the number of retrieved lymph nodes showed no significant difference. The average time to adjuvant chemotherapy was longer in the open group. There was no significant difference in the mean survival time or the recurrence free period.

CONCLUSIONS

Patients who underwent laparoscopic PD using SFA showed perioperative outcomes comparable compared to those of patients who underwent open procedures performed by experienced surgeons.

Central vascular ligation and mesentery based abdominal surgery

In the nineteenth century the idea of a correct surgical approach in oncologic surgery moved towards a good lymphadenectomy. In colon cancer the segment is removed with adjacent mesentery, in gastric cancer or pancreatic cancer a good oncologic resection is obtained with adequate lymphadenectomy. Many guidelines propose a minimal lymph node count that the surgeon must obtain. Therefore, it is essential to understand the adequate extent of lymphadenectomy to be performed in cancer surgery. In this review of the current literature, the focus is on "central vascular ligation", understood as radical lymphadenectomy in upper and lower gastrointestinal cancer, the evolution of this approach during the years and the improvement of laparoscopic techniques. For what concerns laparoscopic surgery, the main goal is to minimize post-operative trauma introducing the "less is more" concept whilst preserving attention for oncological outcomes. This review will demonstrate the importance of a scientifically based standardization of oncologic gastrointestinal surgery, especially in relation to the expansion of minimally invasive surgery and underlines the importance to further investigate through new randomized trials the role of extended lymphadenectomy in the new era of a multimodal approach, and most importantly, an era where minimally invasive techniques and the idea of "less is more" are becoming the standard thought for the surgical approach.

Technical details of a left-side approach to the superior mesenteric artery during pancreaticoduodenectomy

BACKGROUND AND PURPOSE

To describe the procedure for a left-side approach to the superior mesenteric artery (SMA) during pancreaticoduodenectomy (PD) in a cadaveric study.

OPERATIVE PROCEDURE

After dividing the upper jejunum, the jejunal artery (JA) is followed to its origin. At the cranial side of the JA, the mesojejunum to be dissected is detached from the ventral to the dorsal side and from the peripheral to the origin side of the SMA. The inferior pancreatoduodenal artery (IPDA), which is usually the common trunk of the IPDA and the first JA, is able to be visualized at the cranio-dorsal side of the origin of the JA. After cutting the IPDA, the mesojejunum can be detached from the SMA from the dorsal aspect to the right side. Subsequently, the pancreas head is dissected easily from the right aspect of the SMA.

CONCLUSION

This left-side approach to the SMA may become a standard procedure.

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.

[Definition and treatment of superior mesenteric artery revascularization and dissection-associated diarrhea (SMARD syndrome) in Germany]

Hintergrund

Die A. mesenterica superior (AMS) wird im Rahmen von Pankreasresektionen (PR) und mesenterialen Gefäßeingriffen (MG) freigelegt und disseziert. Eine dadurch entstandene Schädigung des umliegenden ex- und intrinsischen vegetativen Nervenplexus kann zu einer passageren oder therapierefraktären Diarrhö führen.

Fragestellung

Die vorliegende Studie soll einen Überblick über den derzeitigen Stellenwert der AMS-Revaskularisations- und -Dissektions-assoziierten Diarrhö („superior mesenteric artery revascularisation and dissection-associated diarrhea“[SMARD]-Syndrom) in Deutschland geben.

Material und Methoden

Nach selektiver Literaturrecherche (SLR) mit der Fragestellung, ob und wie häufig eine postoperativ neu aufgetretene Diarrhö nach PR und MG vorkommt, wurde eine Onlineumfrage versendet.

Ergebnisse

Die SLR (n = 4) bestätigte, dass eine postoperativ neu aufgetretene Diarrhö eine häufige Komplikation nach Präparation zur Revaskularisation (RV) bzw. Dissektion (DIS) der AMS ist (Inzidenz ca. 62 %). Therapierefraktäre Verläufe sind selten 14 %. 54 von 159 Zentren beteiligten sich an der Umfrage. 63 % gaben an, eine AMS-RV/-DIS im Rahmen von PR oder MG durchzuführen. Der Durchschnitt an PR pro Zentrum lag 2018 bei 47 und bei 49 im Jahr 2019. Fünf MG erfolgten durchschnittlich in beiden Jahren pro Zentrum. Drei Patienten litten durchschnittlich am SMARD-Syndrom.

Diskussion

Diese Umfrage erfasst erstmals den derzeitigen Stellenwert des SMARD-Syndroms in Deutschland. Bisher fehlen Empfehlungen zur Therapie einer solchen Diarrhö. Die Ergebnisse zeigen, dass zunächst eine symptomatische Therapie erfolgen sollte. Aufgrund der Komplexität der Pathophysiologie sind kausale Therapieansätze bislang nicht entwickelt.

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.

Technical advances in surgery for pancreatic cancer

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.