Significance of pathological positive superior mesenteric/portal venous invasion in pancreatic cancer

The short- and long-term outcomes of laparoscopic pancreaticoduodenectomy combining with different type of mesentericoportal vein resection and reconstruction for pancreatic head adenocarcinoma: a Chinese multicenter retrospective cohort study

BACKGROUND

The results of laparoscopic pancreaticoduodenectomy combining with mesentericoportal vein resection and reconstruction (LPD-MPVRs) for pancreatic head adenocarcinoma are rarely reported. The aim of present study was to explore the short- and long-term outcomes of different type of LPD-MPVRs.

METHODS

Patients who underwent LPD-MPVRs in 14 Chinese high-volume pancreatic centers between June 2014 and December 2020 were selected and compared.

RESULTS

In total, 142 patients were included and were divided into primary closure (n = 56), end-end anastomosis (n = 43), or interposition graft (n = 43). Median overall survival (OS) and median progress-free survival (PFS) between primary closure and end-end anastomosis had no difference (both P > 0.05). As compared to primary closure and end-end anastomosis, interposition graft had the worst median OS (12 months versus 19 months versus 17 months, P = 0.001) and the worst median PFS (6 months versus 15 months versus 12 months, P < 0.000). As compared to primary closure, interposition graft had almost double risk in major morbidity (16.3 percent versus 8.9 percent) and about triple risk (10 percent versus 3.6 percent) in 90-day mortality, while End-end anastomosis had only one fourth major morbidity (2.3 percent versus 8.9 percent). Multivariate analysis revealed postoperation hospital stay, American Society of Anesthesiologists (ASA) score, number of positive lymph nodes had negative impact on OS, while R0, R1 surgical margin had protective effect on OS. Postoperative hospital stay had negative impact on PFS, while primary closure, end-end anastomosis, short-term vascular patency, and short-term vascular stenosis positively related to PFS.

CONCLUSIONS

In LPD-MPVRs, interposition graft had the worst OS, the worst PFS, the highest rate of major morbidity, and the highest rate of 90-day mortality. While there were no differences in OS and PFS between primary closure and end-end anastomosis.

ANATOMICAL VARIATIONS OF PORTAL VENOUS SYSTEM: IMPORTANCE IN SURGICAL CLINIC

AIM

Knowledge of the portal system and its anatomical variations aids to prevent surgical adverse events. The portal vein is usually made by the confluence of the superior mesenteric and splenic veins, together with their main tributaries, the inferior mesenteric, left gastric, and pancreaticoduodenal veins; however, anatomical variations are frequent. This article presents a literature review regarding previously described anatomical variations of the portal venous system and their frequency.

METHODS

A systematic review of primary studies was performed in the databases PubMed, SciELO, BIREME, LILACS, Embase, ScienceDirect, and Scopus. Databases were searched for the following key terms: Anatomy, Portal vein, Mesenteric vein, Formation, Variation, Variant anatomic, Splenomesenteric vein, Splenic vein tributaries, and Confluence.

RESULTS

We identified 12 variants of the portal venous bed, representing different unions of the splenic vein, superior mesenteric vein, and inferior mesenteric vein. Thomson classification of the end of 19th century refers to the three most frequent variants, with type I as predominant (M=47%), followed by type III (M=27.8%) and type II (M=18.6%).

CONCLUSION

Thomson classification of variants is the most well-known, accounting for over 90% of portal venous variant found in clinical practice, inasmuch as the sum of the three junctions are found in over 93% of the patients. Even though rarer and accounting for less than 7% of variants, the other nine reported variations will occasionally be found during many abdominal operations.

Hemodynamics and remodeling of the portal confluence in patients with malignancies of the pancreatic head: a pilot study towards planned and circumferential vein resections

BACKGROUND

We designed a retrospective computational study to evaluate the effects of hemodynamics on portal confluence remodeling in real models of patients with malignancies of the pancreatic head.

METHODS

Patient-specific models were created according to computed tomography data. Fluid dynamics was simulated by using finite-element methods. Computational results were compared to morphological findings.

RESULTS

Five patients underwent total pancreatectomy, one had duodenopancreatectomy. Vein resection was performed en-bloc with the specimen. Histopathological findings showed that in patients without a vein stenosis and a normal hemodynamics, the three-layered wall of the vein was preserved. In patients with a stenosis > 70% of vein diameter and modified hemodynamics, the three-layered structure of the resected vein was replaced by a dense inflammatory infiltrate in absence of tumor infiltration.

CONCLUSIONS

The portal confluence involved by malignancies of the pancreatic head undergoes a remodeling that is not mainly due to a wall infiltration by the tumor but instead to a persistent pathological hemodynamics that disrupts the balance between eutrophic remodeling and degradative process of the vein wall that can lead to the complete upheaval of the three-layered vein wall. This finding can have useful surgical application in planning resection of the vein involved by tumor growth.

Vascular resection for locally advanced pancreatic ductal adenocarcinoma: analysis of long-term outcomes from a single-centre series

Background

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with poor prognosis. Radical surgery is the best option for cure and, nowadays, it is performed by many surgeons also in cases of vascular infiltration. Whether this aggressive approach to a locally advanced PDAC produces a survival benefit is under debate. Most data in the literature come from retrospective comparative studies; therefore, it is still unclear if such an extensive surgery for an advanced cancer is justified.

Methods

A retrospective review of patients with PDAC treated at our institution over a 12-year period was performed. Data concerning patients’ characteristics, operative details, postoperative course, and long-term survival were retrieved from prospective databases and analysed. Factors associated with poor survival were assessed via Cox regression analysis.

Results

A total of 173 patients with PDAC were included in the analysis, 41 subjects underwent pancreatectomy with vascular resection for locally advanced disease, and in 132 patients, only a pancreatic resection was undertaken. Demographics, major comorbidities, and tumour characteristics were similar between the two groups. Length of surgery (P=0.0006), intraoperative blood transfusions (P<0.0001), and overall complications (P<0.0001) were significantly higher in the vascular resection group. Length of hospital stay (P=0.684) and 90-day mortality (P=0.575) were comparable between groups. Overall median survival (P= 0.717) and survival rates at 1, 3, and 5 years (P=0.964, P=0.500, and P=0.445, respectively) did not differ significantly between groups. Age ≥70 years and postoperative complications were independent predictors of lower survival.

Conclusions

Our study confirms that pancreatectomy with vascular resection for a locally advanced PDAC is a complex operation associated with a significant longer operating time that may increase morbidity; however, in selected patients, R0 margins can be obtained with an acceptable long-term survival rate. Older patients are less likely to benefit from surgery.

Comprehensive histological evaluation with clinical analysis of venous invasion in pancreatic ductal adenocarcinoma: From histology to clinical implications

OBJECTIVES

Venous invasion is a poor prognostic factor for pancreatic ductal adenocarcinoma (PDAC). However, our understanding of various features of venous invasion is limited. Our aim is to comprehensively evaluate various histopathologic features of venous invasion, including status, type (lymphatic or venous), number of invasion foci, and histologic pattern (pancreatic intraepithelial neoplasia [PanIN]-like, conventional) in PDACs.

METHODS

Various features of venous invasion, including status, number of invasion foci, histologic patterns [pancreatic intraepithelial neoplasia (PanIN)-like, conventional], and size of involved vessels in 471 surgically resected PDACs were evaluated with all available hematoxylin and eosin (H&E)-stained slides.

RESULTS

Venous invasion was observed in 319 cases (67.7%) and was more frequently associated with increased tumor size, extrapancreatic extension, resection margin involvement, diffuse tumor distribution, lymph node metastasis, and perineural invasion (all Ps < .05). High frequency (≥3 foci) of venous invasion was associated with shorter overall survival both in the entire group and in the early stage subgroup (stage I; all Ps < .05). Multivariate analysis indicated that a high frequency (≥3 foci) of venous invasion, large tumor size (>4 cm), higher histologic grade, and lymph node metastasis, were independent prognostic factors of worse overall survival (all Ps < .05).

CONCLUSION

Precise evaluation of venous invasion status, including foci number of invasion, can provide additional prognostic information for patients undergoing surgical resection of PDAC, especially for those with early disease stage.

Open and Minimal Approaches to Pancreatic Adenocarcinoma

Surgical options and approaches to pancreatic cancer are changing in the current era. Neoadjuvant treatment strategies for pancreatic cancer combined with the increased use of minimal access surgical techniques mean that the modern pancreatic surgeon requires mastering a number of surgical approaches with to optimally manage patients. Whilst traditional open surgery remains the most frequent approach for surgery, the specific steps during surgery may need to be modified in light of the aforementioned neoadjuvant treatments. Robotic and laparoscopic approaches to pancreatic resection are feasible, but these surgical methods remain in their infancy. In this review article, we summarise the current surgical approaches to pancreatic cancer and how these are adapted to the minimal access setting with discussion of the patient outcome data.

Data set for the reporting of pheochromocytoma and paraganglioma: explanations and recommendations of the guidelines from the International Collaboration on Cancer Reporting

BACKGROUND AND OBJECTIVES

The International Collaboration on Cancer Reporting (ICCR) is a not-for-profit to develop evidence-based, internationally agreed-upon standardized data sets for each anatomic site, to be used throughout the world. Providing global standardization of pathology tumor classification, staging, and other reporting elements will lead to improved patient management and enhanced epidemiological research.

METHODS

Pheochromocytoma and paraganglioma are uncommon and are frequently overlooked in registry data sets. Malignant criteria have previously been defined only when there was metastatic disease.

RESULTS

With recent recognition of a significant inheritance association and the development of risk stratification tools, this data set was created in order to obtain more meaningful outcomes and management data, using similar criteria across the global pathology community. Issues related to key core and non-core elements, especially clinical hormonal status, familial history, tumor focality, proliferative fraction, adverse or risk stratification features, and ancillary techniques, are discussed in the context of daily application to these types of specimens.

CONCLUSIONS

The ICCR data set, developed by an international panel of endocrine organ specialists, establishes a pathology-standardized reporting guide for pheochromocytoma and paraganglioma.

Vascular Resection for Pancreatic Cancer: 2019 French Recommendations Based on a Literature Review From 2008 to 6-2019

Introduction: Vascular resection remains a subject of debate in the management of Pancreatic Ductal Adenocarcinoma (PDAC). These French recommendations were drafted on behalf of the French National Institute of Cancer (INCA-2019).

Material and Methods: A systematic literature search, with PubMed, Medline® (OvidSP), EMBASE, the Cochrane Library, was performed for abstracts published in English from January 2008 to June 2019, and identified systematic reviews/metaanalyses, retrospective analyses and case series dedicated to vascular resections in the setting of PDAC. All selected articles were graded for level of evidence and strength of recommendation was given according to the GRADE system.

Results: Neoadjuvant treatment should be performed rather than direct surgery in borderline and locally advanced non-metastatic PDAC with venous and/or arterial infiltration (T4 stage). Patients who respond or those with stable disease and good performance status should undergo surgical exploration to assess resectability because cross-sectional imaging often fails to identify the extent of the remaining viable tumor. Combining vascular resection with pancreatectomy in these cases increases the feasibility of curative resection which is still the only option to improve long-term survival. Venous resection (VR) is recommended if resection is possible in the presence of limited lateral or circumferential involvement but without venous occlusion and in the absence of arterial contact with the celiac axis (CA; cephalic tumors) or the superior mesenteric artery (SMA; all tumor locations) (Grade B). The patients should be in good general condition because mortality and morbidity are higher than following pancreatectomy without VR (Grade B). In case of planned VR, neoadjuvant treatment is recommended since it improves both rate of R0 resections and survival compared to upfront surgery (Grade B). Due to their complexity and specificities, arterial resection (AR; mainly the hepatic artery (HA) or the CA) must be discussed in selected patients, in multidisciplinary team meetings in tertiary referral centers, according to the tumor location and the type of arterial extension. In case of invasion of a short segment of the common HA, resection with arterial reconstruction may be proposed after neoadjuvant therapy. In case of SMA invasion, neoadjuvant therapy may be followed by laparotomy with dissection and biopsy of peri-arterial tissues. A pancreaticoduodenectomy (PD) with SMA-resection is not recommended if the frozen section examination is positive (Grade C). In case of distal PDAC with invasion of the CA, a distal pancreatectomy with CA-resection without arterial reconstruction may be proposed after neoadjuvant therapy and radiologic embolization of the CA branches (expert opinion).

Conclusion: For PDAC with vascular involvement, neoadjuvant treatment followed by pancreatectomy with venous resection or even arterial resection can be proposed as a curative option in selected patients with selected vascular involvement.