Vascular invasion in pancreatic cancer: Imaging modalities, preoperative diagnosis and surgical management

Surgical Indications and Outcomes of Resection for Pancreatic Neuroendocrine Tumors with Vascular Involvement

Simple Summary

Pancreatic neuroendocrine tumors (pNETs) are a heterogenous group of rare epithelial neoplasms. For most patients, surgery remains the only treatment modality to cure pNETs, and is recommended for patients with surgically resectable disease. Many of these tumors are non-functional tumors and do not produce clinical symptoms, so patients may present with locally advanced tumors, which invade surrounding organs or neighboring blood vessels. The presence of vascular involvement had previously been considered a contraindication to surgery, but, in recent years, at centers with considerable experience, aggressive surgery to remove pNETs with vascular reconstruction has been performed safely and with good long-term survival. In this review, we will discuss the considerations for resectability, review novel surgical approaches, and present the available evidence on the immediate and long-term postoperative outcomes.

Abstract

Complete surgical resection of pancreatic neuroendocrine tumors (pNETs) has been suggested as the only potentially curative treatment. A proportion of these tumors will present late during disease progression, and invade or encase surrounding vasculature; therefore, surgical treatment of locally advanced disease remains controversial. The role of surgery with vascular reconstruction in pNETs is not well defined, and there is considerable variability in the use of aggressive surgery for these tumors. Accurate preoperative assessment is critical to evaluate individual considerations, such as anatomical variants, areas and lengths of vessel involvement, proximal and distal targets, and collateralization secondary to the degree of occlusion. Surgical approaches to address pNETs with venous involvement may include thrombectomy, traditional vein reconstruction, a reconstruction-first approach, or mesocaval shunting. Although the amount of literature on pNETs with vascular reconstruction is limited to case reports and small institutional series, the last two decades of studies have demonstrated that aggressive resection of these tumors can be performed safely and with acceptable long-term survival.

Intravascular Ultrasound for the Evaluation and Management of Retroperitoneal, Genitourinary Malignancies

PURPOSE OF REVIEW

Herein we provide a review of intravascular ultrasound (IVUS) and its ability to assist in the evaluation and surgical management of advanced retroperitoneal, genitourinary tumors.

RECENT FINDINGS

Advanced retroperitoneal tumors such as advanced renal cell carcinoma, bulky retroperitoneal lymphadenopathy associated with advanced testicular carcinoma, large adrenal tumors, and retroperitoneal sarcomas can invade, compress, or distort vascular anatomy making surgical resection challenging and high risk. Intravascular ultrasonography is commonly used by vascular and cardiothoracic surgery to provide a real time assessment of vascular invasion, compression, and aberrant anatomy to assist with pre-operative and/or intraoperative decision-making. However, the application of this technology to assist with cancer surgery has been limited. The use of intravascular ultrasound prior to radical, extirpative, retroperitoneal surgery involving large vessels can aid in the planning and execution of such challenging operations.

Pancreatic adenocarcinoma: A review of recent paradigms and advances in epidemiology, clinical diagnosis and management

Pancreatic cancer is one of the dreaded malignancies for both the patient and the clinician. The five-year survival rate of pancreatic adenocarcinoma (PDA) is as low as 2% despite multimodality treatment even in the best hands. As per the Global Cancer Observatory of the International Agency for Research in Cancer estimates of pancreatic cancer, by 2040, a 61.7% increase is expected in the total number of cases globally. With the widespread availability of next-generation sequencing, the entire genome of the tumors is being sequenced regularly, providing insight into their pathogenesis. As invasive PDA arises from pancreatic intraepithelial neoplasia and mucinous neoplasm and intraductal papillary neoplasm, screening for them can be beneficial as the disease is curable with resection at an early stage. Routine preoperative biliary drainage has no role in patients suffering from PDA with obstructive jaundice. If performed, metallic stents are preferred over plastic ones. Minimally invasive procedures are preferred to open procedures as they have less morbidity. The duct-to-mucosa technique for pancreaticojejunostomy is presently widely practiced. The role of intraperitoneal drains after surgery for PDA is controversial. Neoadjuvant chemoradiotherapy has been proven to have a significant role both in locally advanced as well as in resectable PDA. Many new regimens and drugs have been added in the arsenal of chemoradiotherapy for metastatic disease. The roles of immunotherapy and gene therapy in PDA are being investigated. This review article is intended to improve the understanding of the readers with respect to the latest updates of PDA, which may help to trigger new research ideas and make better management decisions.

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

Simple Summary

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

Abstract

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

The Bromodomain Inhibitor, INCB057643, Targets Both Cancer Cells and the Tumor Microenvironment in Two Preclinical Models of Pancreatic Cancer

Simple Summary

Pancreatic cancer remains a highly lethal disease, with only ~10% of patients still alive five years after diagnosis, as most patients already have advanced, metastatic disease at the time of diagnosis. Therefore, new treatments are needed for these patients. We tested INCB057643, a novel bromodomain inhibitor, in a relevant mouse model of pancreatic cancer, and this compound improves survival and reduces metastasis. Pancreatic cancers are very dense, as the stroma within the tumor can account for up to 90% of the tumor mass and is responsible for the failure of many drugs. INCB057643 modulates the immune cells within the tumor so they can attack and kill tumor cells. INCB057643 also alters immune cells within the pancreas in a mouse model of pancreatitis, which is inflammation of the pancreas that can promote the development of pancreatic cancer.

Abstract

In pancreatic cancer the tumor microenvironment (TME) can account for up to 90% of the tumor mass. The TME drives essential functions in disease progression, invasion and metastasis. Tumor cells can use epigenetic modulation to evade immune recognition and shape the TME toward an immunosuppressive phenotype. Bromodomain inhibitors are a class of drugs that target BET (bromodomain and extra-terminal) proteins, impairing their ability to bind to acetylated lysines and therefore interfering with transcriptional initiation and elongation. INCB057643 is a new generation, orally bioavailable BET inhibitor that was developed for treating patients with advanced malignancies. Kras^G12D/+; Trp53^R172H/+; Pdx-1-Cre (KPC) mice mimic human disease, with similar progression and incidence of metastasis. Treatment of established tumors in KPC mice with INCB057643 increased survival by an average of 55 days, compared to the control group. Moreover, INCB057643 reduced metastatic burden in these mice. KPC mice treated with INCB057643, starting at 4 weeks of age, showed beneficial changes in immune cell populations in the pancreas and liver. Similarly, INCB057643 modified immune cell populations in the pancreas of Kras^G12D/+; Pdx-1-Cre (KC) mice with pancreatitis, an inflammatory process known to promote pancreatic cancer progression. The data presented here suggest that the bromodomain inhibitor INCB057643 modulates the TME, reducing disease burden in two mouse models of pancreatic cancer. Furthermore, this work suggests that BRD4 may play a role in establishing the TME in the liver, a primary metastatic site for pancreatic cancer.

Use of imaging as staging and surgical planning for pancreatic surgery

Importance

In the past few decades, there has been rapid advancements in imaging technologies that have become irreplaceable in the pre-operative assessment of patients with pancreatic tumors. Modern imaging modalities, including computed tomography (CT) and endoscopic ultrasound (EUS), can provide critical information of the absence or presence of metastatic disease in pancreatic cancer, as well as details on the local extent and resectability, allowing for the selection of stage appropriate treatments and pre-operatively determined surgical approach.

Objective

The aim of this review is to discuss staging, resectability, and imaging for patients with pancreatic tumors.

Evidence Review

A literature review was performed of articles relevant to the topics of staging, resectability, and imaging of pancreatic tumors. Imaging modalities included CT, EUS, magnetic resonance imaging (MRI), positron emission tomography (PET), antibody-based and narrow band imaging.

Findings

CT pancreas protocol combined with EUS serve as the primary modalities in diagnosis, staging, and surgical planning in patients with pancreatic tumors. MRI is an alternative to CT with near equivalent utility in the pre-operative setting. In some circumstances, PET-CT may be a cost-effective initial study to detect distant disease.

Conclusions and Relevance

Current imaging technologies play a critical role in the evaluation of patients with pancreatic tumors. Advances in the past 3 decades in imaging technologies have revolutionized the process of assessment of stage and resectability in patients with pancreatic tumors. Future imaging technologies will address current limitation in the evaluation of occult metastatic disease.

High-resolution intravascular MRI-guided perivascular ultrasound ablation

PURPOSE

To develop and test in animal studies ex vivo and in vivo, an intravascular (IV) MRI-guided high-intensity focused ultrasound (HIFU) ablation method for targeting perivascular pathology with minimal injury to the vessel wall.

METHODS

IV-MRI antennas were combined with 2- to 4-mm diameter water-cooled IV-ultrasound ablation catheters for IV-MRI on a 3T clinical MRI scanner. A software interface was developed for monitoring thermal dose with real-time MRI thermometry, and an MRI-guided ablation protocol developed by repeat testing on muscle and liver tissue ex vivo. MRI thermal dose was measured as cumulative equivalent minutes at 43°C (CEM₄₃ ). The IV-MRI IV-HIFU protocol was then tested by targeting perivascular ablations from the inferior vena cava of 2 pigs in vivo. Thermal dose and lesions were compared by gross and histological examination.

RESULTS

Ex vivo experiments yielded a 6-min ablation protocol with the IV-ultrasound catheter coolant at 3-4°C, a 30 mL/min flow rate, and 7 W ablation power. In 8 experiments, 5- to 10-mm thick thermal lesions of area 0.5-2 cm² were produced that spared 1- to 2-mm margins of tissue abutting the catheters. The radial depths, areas, and preserved margins of ablation lesions measured from gross histology were highly correlated (r ≥ 0.79) with those measured from the CEM₄₃ = 340 necrosis threshold determined by MRI thermometry. The psoas muscle was successfully targeted in the 2 live pigs, with the resulting ablations controlled under IV-MRI guidance.

CONCLUSION

IV-MRI-guided, IV-HIFU has potential as a precision treatment option that could preserve critical blood vessel wall during ablation of nonresectable perivascular tumors or other pathologies.

Preoperative CT findings for prediction of resectability in patients with gallbladder cancer

OBJECTIVES

To predict residual tumor (R) classification in patients with a surgery for gallbladder (GB) cancer, using preoperative CT.

METHODS

One hundred seventy-three patients with GB cancer who underwent CT and subsequent surgery were included. Two radiologists assessed CT findings, including tumor morphology, location, T stage, adjacent organ invasion, hepatic artery (HA) invasion, portal vein invasion, lymph node metastasis, metastasis, resectability, gallstone, and combined cholecystitis. The R classification was categorized as no residual tumor (R0) and residual tumor (R1 or R2). We analyzed the correlation between CT findings and R classification. We also followed up the patients as long as five years and analyzed the relationship between the R classification and the overall survival (OS).

RESULTS

There were 134 patients with R0 and 39 patients with R1/R2. On multivariable analysis, liver invasion (Exp(B) = 3.19, p = 0.010), bile duct invasion (Exp(B) = 3.69, p = 0.031), and HA invasion (Exp(B) = 3.74, p = 0.039) were independent, significant predictors for residual tumor. When two of these three criteria were combined, the accuracy for predicting a positive resection margin was 83.38% with a specificity of 93.28%. The OS and the median patient survival time differed significantly according to the resection margin, i.e., 56.0% and 134.4 months in the R0 resection and 5.1% and 10.8 months in the R1/R2 resection group (p < 0.001).

CONCLUSIONS

Preoperative CT findings could aid in planning surgery and determining the resectability using the high-risk findings of residual tumor, including liver invasion, bile duct invasion, and HA invasion.

KEY POINTS

• Liver invasion, bile duct invasion, and HA invasion were significant preoperative CT predictors for residual tumor in GB cancer. • HA invasion showed the highest OR on multivariate analysis and the highest predictor point on a nomogram for predicting a positive resection margin. • Association of two factors can predict positive resection margin with an accuracy of 83.38% and a specificity of 93.28%.

A promising tool for T-staging of lung cancer: Is convex probe endobronchial ultrasound superior to computed tomography in detecting invasion of mediastinal and hilar vessels?

Background

In the present study, we aimed to compare performance of convex probe endobronchial ultrasound and computed tomography in detecting vascular invasion of mediastinal and hilar lesions.

Methods

Medical data of a total of 55 patients (47 males, 8 females; mean age 59.6±7.7 years; range, 29 to 76 years) who underwent convex probe endobronchial ultrasound for diagnosis and staging of lung cancer in a tertiary care hospital between May 2016 and December 2017 were retrospectively analyzed. The presence of vascular invasion was determined according to two main criteria: visualization of the tumor tissue within the vessel lumen and loss of vessel-tumor hyperechoic interface. All available contrast enhanced computed tomography images were retrospectively re-evaluated by a blinded radiologist. The intra-rater agreement between convex probe endobronchial ultrasound and computed tomography was analyzed. The sensitivity, specificity, positive and negative predictive values, and accuracy of both modalities were calculated.

Results

A total of 65 vessel-tumor interface areas of 55 patients were analyzed. Almost all mediastinal and hilar vascular structures including pulmonary arteries and veins, aorta, superior vena cava and its branches, and left atrium with pulmonary veno-atrial junctions could be easily assessed by convex probe endobronchial ultrasound. The intra-agreement of both modalities in detecting vascular invasion was k=0.268 (p=0.028). In nine patients with a surgical confirmation, the sensitivity, specificity, positive and negative predictive values, and accuracy values were 100%, 33.3%, 75.0%, 100%, and 77.7%, respectively for convex probe endobronchial ultrasound and 66.6%, 33.3%, 66.6%, 33.3%, and 55.5%, respectively for computed tomography.

Conclusion

Convex probe endobronchial ultrasound can be used to detect vascular invasion alone or in conjunction with contrast-enhanced computed tomography. Hence, a T₄ lesion would be better differentiated from T₃ in clinical staging of lung cancer.

Diagnostic Ability of Convex-Arrayed Endoscopic Ultrasonography for Major Vascular Invasion in Pancreatic Cancer

Background/Aims

This study aimed to examine the diagnostic ability of endoscopic ultrasonography (EUS) for major vascular invasion in pancreatic cancer and to evaluate the relationship between EUS findings and pathological distance.

Methods

In total, 57 consecutive patients who underwent EUS for pancreatic cancer before surgery were retrospectively reviewed. EUS image findings were divided into four types according to the relationship between the tumor and major vessel (types 1 and 2: invasion, types 3 and 4: non-invasion). We also compared the EUS findings and pathologically measured distances between the tumors and evaluated vessels.

Results

The sensitivity, specificity, and accuracy of EUS diagnosis for vascular invasion were 89%, 92%, and 91%, respectively, in the veins and 83%, 94%, and 93%, respectively, in the arteries. The pathologically evaluated distances of cases with type 2 EUS findings were significantly shorter than those of cases with type 3 EUS findings in both the major veins (median [interquartile range], 96 [0–742] µm vs. 2,833 [1,076–5,694] µm, p=0.012) and arteries (623 [0–854] µm vs. 3,097 [1,396–6,000] µm, p=0.0061). All cases with a distance of ≥1,000 µm between the tumors and main vessels were correctly diagnosed.

Conclusions

Tumors at a distance ≥1,000 µm from the main vessels were correctly diagnosed by EUS.

Preoperative prediction of peripancreatic vein invasion by pancreatic head cancer

Background

Pancreatic adenocarcinoma is often diagnosed at an advanced stage when adjacent vascular invasion is present. Accurate evaluation of presence of vascular invasion can help guide therapy. The aim of this study was to construct a nomogram for preoperative prediction of peripancreatic vein invasion in patients with pancreatic head cancer.

Study design

Data of patients with carcinoma head of pancreas and suspected peripancreatic invasion (n = 247) who underwent pancreatic resection with venous reconstruction between January 2012 and January 2017 at four academic institutions were retrospectively analyzed. Univariate and multivariate analyses were used to identify independent risk factors for vein invasion from among demographic, biological, conditional host-related, and anatomical data. A predictive nomogram was constructed based on the identified independent risk factors.

Results

The nomogram was constructed using data from 181 patients while the validation cohort consisted of 66 patients. Length of tumor contact (P = 0.031), circumferential vein involvement (P = 0.048), and venous contour abnormalities (P = 0.001) were independent predictors of venous invasion. The C-index of the model in predicting venous invasion was 0.963 for the external validation cohort. Patients could be assigned into low- (< 50%), intermediate- (50–90%), and high-risk (> 90%) groups based on the nomogram to facilitate personalized management.

Conclusions

Vein invasion by pancreatic head cancer is mainly associated with anatomical factors. The nomogram for prediction of vein invasion was found to be practicable.

Electronic supplementary material

The online version of this article (10.1186/s40644-018-0179-z) contains supplementary material, which is available to authorized users.

CT imaging of primary pancreatic lymphoma: experience from three referral centres for pancreatic diseases

Purpose

To describe CT characteristics of primary pancreatic lymphoma (PPL), a rare disease with features in common with adenocarcinoma.

Materials and methods

Fourteen patients were enrolled. CT: unenhanced scan, contrast-enhanced pancreatic and venous phases. Image analysis: tumour location; peri-pancreatic vessel encasement; necrosis; enlarged lymph nodes; fat stranding; enlarged bile duct and pancreatic duct; neoplasm longest dimension, volume and density.

Results

Histopathological diagnoses: follicular non-Hodgkin lymphoma (5/14), diffuse large B-cell lymphoma (6/14) and high-grade B-cell lymphoma not otherwise specified (3/14). Six of 14 PPLs were located in the pancreatic head and 7/14 in the body-tail; 1/14 involved the whole gland. In 5/14 cases the superior mesenteric artery and vein were encased; splenic vein and artery encasement was depicted in 2 PPLs. Necrosis was present in 2/14. Enlarged retroperitoneal lymph nodes were found in 11 cases and fat stranding in all patients. The bile duct was dilated in six cases and the pancreatic duct in five. Mean neoplasm longest diameter and volume were 8.05 cm and 210.8 cm³. Mean tumour attenuation values were 39.1 HU at baseline, 60.6 HU in the pancreatic phase and 71.4 HU in the venous phase.

Conclusions

PPL presents as a large mass lesion with delayed homogeneous enhancement; peri-pancreatic fat stranding and vessel encasement are present, without vascular infiltration. Pancreatic duct dilatation is rare.

Key points

• Primary pancreatic lymphoma (PPL) is a rare haematological disease

• PPL presents imaging features in common with pancreatic carcinoma but also some distinctive findings

• The majority of PPLs are large lesions with delayed homogeneous enhancement

• Peri-pancreatic fat stranding and vessel encasement are common in PPL

• Vascular infiltration and pancreatic duct dilatation are rare in PPL

Dual-Frequency Piezoelectric Endoscopic Transducer for Imaging Vascular Invasion in Pancreatic Cancer

Cancers of the pancreas have the poorest prognosis among all cancers, as many tumors are not detected until surgery is no longer a viable option. Surgical viability is typically determined via endoscopic ultrasound imaging. However, many patients who may be eligible for resection are not offered surgery due to diagnostic challenges in determining vascular or lymphatic invasion. In this paper, we describe the development of a dual-frequency piezoelectric transducer for rotational endoscopic imaging designed to transmit at 4 MHz and receive at 20 MHz in order to image microbubble-specific superharmonic signals. Imaging performance is assessed in a tissue-mimicking phantom at depths from 1 cm [contrast-to-tissue ratio (CTR) = 21.6 dB] to 2.5 cm (CTR = 11.4 dB), in ex vivo porcine vessels, and in vivo in a rodent. The prototyped 1.1-mm aperture transducer demonstrates contrast-specific imaging of microbubbles in a 200- [Formula: see text]-diameter tube through the wall of a 1-cm-diameter porcine artery, suggesting such a device may enable direct visualization of small vessels from within the lumen of larger vessels such as the portal vein or superior mesenteric vein.

A Combined Intravascular MRI Endoscope and Intravascular Ultrasound (IVUS) Transducer for High-Resolution Image-Guided Ablation

An intravascular MRI (IMRI) loopless antenna is combined for the first time with an intravascular water-cooled ultrasound ablation transducer as a possible tool for providing high-resolution MRI-guided ablations of pathological tissue via intravascular access. High resolution anatomical MRI, and real-time MRI thermometry were used to monitor ablation delivery in phantoms and tissue specimens. Results show that IMRI can guide IVUS-mediated directional ablation with minimal image artifacts. This permits the monitoring of thermal dose and therapy titration while minimizing potential thermal damage to the vessel wall.

Distal Pancreatectomy With En Bloc Celiac Axis Resection for Locally Advanced Pancreatic Cancer: A Systematic Review and Meta-Analysis

Although distal pancreatectomy with en bloc celiac resection (DP-CAR) is used to treat locally advanced pancreatic cancer, the advantages and disadvantages of this surgical procedure remain unclear. The purpose of this study was to evaluate its clinical safety and efficacy.Studies regarding DP-CAR were retrieved from the following databases: PubMed, EMBASE, Web of Science, Cochrane Library, and Chinese electronic databases. Articles were selected according to predesigned inclusion criteria, and data were extracted according to predesigned sheets. Clinical, oncologic, and survival outcomes of DP-CAR were systematically reviewed by hazard ratios (HRs) or odds ratio (OR) using fixed- or random-effects models.Eighteen studies were included. DP-CAR had a longer operating time and greater intraoperative blood loss compared to distal pancreatectomy (DP). A high incidence of vascular reconstruction occurred in DP-CAR: 11.53% (95%CI: 6.88-18.68%) for artery and 33.28% (95%CI: 20.45-49.19%) for vein. The pooled R0 resection rate of DP-CAR was 72.79% (95% CI, 46.19-89.29%). Higher mortality and morbidity rates were seen in DP-CAR, but no significant differences were detected compared to DP; the pooled OR was 1.798 for mortality (95% CI, 0.360-8.989) and 2.106 for morbidity (95% CI, 0.828-5.353). The pooled incidence of postoperative pancreatic fistula (POPF) was 31.31% (95%CI, 23.69-40.12%) in DP-CAR, similar to that of DP (OR = 1.07; 95%CI, 0.52-2.20). The pooled HR against DP-CAR was 5.67 (95%CI, 1.48-21.75) for delayed gastric emptying. The pooled rate of reoperation was 9.74% (95%CI, 4.56-19.59%) in DP-CAR. The combined 1-, 2-, and 3-year survival rates in DP-CAR were 65.22% (49.32-78.34%), 30.20% (21.50-40. 60%), and 18.70% (10.89-30.13%), respectively. The estimated means and medians for survival time in DP-CAR patients were 24.12 (95%CI, 18.26-29.98) months and 17.00 (95%CI, 13.52-20.48) months, respectively. There were no significant differences regarding postoperative 1-, 2-, and 3-year survival rates between DP-CAR and DP, whereas DP-CAR had a better 1-year survival rate compared to palliative treatments. The pooled HR for overall survival between DP-CAR and DP was 1.36 (95%CI: 0.997-1.850); the pooled HR favoring DP-CAR was 0.38 (95%CI: 0.25-0.58) for overall survival compared to palliative treatments. The rate of cancer-related pain relief from DP-CAR was 89.20% (95%CI, 77.85-95.10%). The pooled incidence of postoperative diarrhea was 37.10% (95%CI, 20.79-57.00%); however, most diarrhea was effectively controlled.DP-CAR is feasible and acceptable in terms of its survival benefits and improved quality of life. However, it should be performed with caution due to its high postoperative morbidity.

Inferior mesenteric vein serves as an alternative guide for transection of the pancreatic body during pancreaticoduodenectomy with concomitant vascular resection: a comparative study evaluating perioperative outcomes

BACKGROUND

Tumors of the pancreatic head often involve the superior mesenteric and portal veins. The purpose of this study was to assess perioperative outcomes after pancreaticoduodenectomy (PD) with concomitant vascular resection using the inferior mesenteric vein (IMV) as a guide for transection of the pancreatic body (Whipple at IMV, WATIMV).

METHODS

One hundred thirty-seven patients had segmental vein resection during PD between January 2006 and June 2013. Depending on whether the standard approach of creating a tunnel anterior to the mesenterico-portal vein (MPV) axis was achieved for pancreatic transection, patients were subjected to a standard PD with vein resection procedure (s-PD + VR, n = 75) or a modified procedure (m-PD + VR, n = 62). Within the m-PD + VR group, 28 patients underwent the WATIMV procedure, while 34 patients underwent the usual procedure of transection, or 'central pancreatectomy' (c-PD + VR).

RESULTS

The volume of intraoperative blood loss and the blood transfusion requirements were significantly greater, and the venous wall invasion and neural invasion frequency were significantly higher in the m-PD + VR group compared with the s-PD + VR group. There were no significant differences in the length of hospitalization, postoperative morbidity, and grades of complications between the two groups. Multivariate logistic regression identified intraoperative blood transfusion (P = 0.004) and vascular invasion (P = 0.008) as the predictors of postoperative morbidity. Further stratification of the entire cohort of 62 (45%) patients who underwent m-PD + VR showed a higher rate of negative resection margins (96.4%) in the WATIMV group compared with the c-PD + VR group (76.5%) (P = 0.06). The volume of intraoperative blood loss (P = 0.013), and intraoperative blood transfusion requirements (P = 0.07) were significantly greater in the c-PD + VR group compared with the WATIMV group. Furthermore, high intraoperative blood loss and tumor stage were predictive of a positive resection margin.

CONCLUSIONS

'Whipple at the IMV (WATIMV)' has comparable postoperative morbidity with standard PD + VR. If IMV runs into the splenic vein, it could serve as an alternative guide for transection of the pancreatic body during PD + VR.

Current and future intraoperative imaging strategies to increase radical resection rates in pancreatic cancer surgery

Prognosis of patients with pancreatic cancer is poor. Even the small minority that undergoes resection with curative intent has low 5-year survival rates. This may partly be explained by the high number of irradical resections, which results in local recurrence and impaired overall survival. Currently, ultrasonography is used during surgery for resectability assessment and frozen-section analysis is used for assessment of resection margins in order to decrease the number of irradical resections. The introduction of minimal invasive techniques in pancreatic surgery has deprived surgeons from direct tactile information. To improve intraoperative assessment of pancreatic tumor extension, enhanced or novel intraoperative imaging technologies accurately visualizing and delineating cancer cells are necessary. Emerging modalities are intraoperative near-infrared fluorescence imaging and freehand nuclear imaging using tumor-specific targeted contrast agents. In this review, we performed a meta-analysis of the literature on laparoscopic ultrasonography and we summarized and discussed current and future intraoperative imaging modalities and their potential for improved tumor demarcation during pancreatic surgery.

A tumour score with multidetector spiral CT for venous infiltration in pancreatic cancer: influence on borderline resectable

PURPOSE

A tumour score for venous invasion in patients with pancreatic adenocarcinoma was evaluated by means of computed tomography (CT), in order to improve the assessment of medical treatment and clinical outcome with special attention to borderline resectable disease.

MATERIALS AND METHODS

Fifty-six consecutive patients who underwent curative surgical resection for pancreatic cancer were analysed. On the basis of CT criteria, tumour involvement of the portal vein (PV) and superior mesenteric vein (SMV) was graded according to an adapted 4-point scale: score 1, definite absence of invasion; score 2, probable absence of invasion; score 3, probable presence of invasion; score 4, definite presence of invasion. Correlations between the venous infiltration scores and the patients' clinical features were also evaluated.

RESULTS

After radiological evaluation of PV and SMV grades of infiltration, 21/56 (37 %) and 37/56 (66 %) patients, respectively, were found to have borderline resectable disease. The 4-point scale achieved a sensitivity of 80 %, a specificity of 96 % and an accuracy of 93 % in the evaluation of the PV, and a sensitivity of 100 %, a specificity of 94 % and an accuracy of 95 % in the evaluation of the SMV. Analysis of the distribution of clinical characteristics by PV and SMV infiltration showed that both scores correlated with the presence of distal metastasis (p = 0.016 and p = 0.028, respectively), and resection margins status (p = 0.015 and p = 0.006, respectively).

CONCLUSIONS

This adapted tumour score is reliable for assessing venous invasion and might improve preoperative staging in patients with borderline resectable pancreatic cancer.

Is superior mesenteric artery reimplantation during surgery for pancreaticoduodenal tumors an underutilized procedure?

Resection and reimplantation of the superior mesenteric artery (SMA) as part of a pancreaticoduodenal resection for cancer is rarely performed even in high-volume centers because of the risks inherent in this procedure and the perceived lack of oncological benefit associated with arterial resection during pancreaticoduodenectomy. The role of arterial resection during pancreaticoduodenectomy has recently been reevaluated, and this procedure may be of greater benefit than previously believed in selected patients. It also has a definite role when necessary to resect low-grade pancreatic and peripancreatic malignancies or to salvage intraoperative injury to the SMA. This small case series presents the authors experience with this procedure.

Distal pancreatectomy with en bloc celiac axis resection for locally advanced pancreatic adenocarcinoma following neoadjuvant therapy

BACKGROUND

Celiac trunk encasement by adenocarcinoma of the pancreatic body is generally regarded as a contraindication for surgical resection. Recent studies have suggested that a subset of stage III patients will succumb to their disease in the absence of distant metastases. We hypothesized that patients with stage III tumors invading the celiac trunk, who are free of distant disease following neoadjuvant therapy, may derive prolonged survival benefit from aggressive surgical resection.

METHODS

We performed a retrospective review of distal pancreatectomies with en bloc celiac axis resection for pancreatic adenocarcinoma.

RESULTS

Eleven patients underwent a distal pancreatectomy with en bloc celiac axis resection after completing neoadjuvant chemoradiation therapy. Median operative time was 8 h, 14 min, and median estimated blood loss was 700 ml. Median length of stay was 9 days. Five patients (45%) had postoperative complications; three were Clavien grade I. Four patients (35%) had pancreatic leaks; two were ISGPF grade B, and two were grade A. There were two 90-day perioperative deaths. Ten patients had R0 resections (91%). After a median follow-up of 41 weeks, six patients recurred. Four of the five patients with SMAD4 loss recurred, and two of the five patients with intact SMAD4 recurred. Median disease-free and overall survival were 21 weeks and 26 months, respectively.

CONCLUSIONS

Resection of pancreatic body adenocarcinoma with celiac axis resection is technically feasible with acceptable perioperative morbidity and mortality.

Pancreatic adenocarcinoma: Outstanding problems

Pancreatic adenocarcinoma remains the fourth leading cause of cancer-related death and is one of the most aggressive malignant tumors with an overall 5-year survival rate of less than 4%. Surgical resection remains the only potentially curative treatment but is only possible for 15%-20% of patients with pancreatic adenocarcinoma. About 40% of patients have locally advanced nonresectable disease. In the past, determination of pancreatic cancer resectability was made at surgical exploration. The development of modern imaging techniques has allowed preoperative staging of patients. Institutions disagree about the criteria used to classify patients. Vascular invasion in pancreatic cancers plays a very important role in determining treatment and prognosis. There is no evidence-based consensus on the optimal preoperative imaging assessment of patients with suspected pancreatic cancer and a unified definition of borderline resectable pancreatic cancer is also lacking. Thus, there is much room for improvement in all aspects of treatment for pancreatic cancer. Multi-detector computed tomography has been widely accepted as the imaging technique of choice for diagnosing and staging pancreatic cancer. With improved surgical techniques and advanced perioperative management, vascular resection and reconstruction are performed more frequently; patients thought once to be unresectable are undergoing radical surgery. However, when attempting heroic surgery, a realistic approach concerning the patient’s age and health status, probability of recovery after surgery, perioperative morbidity and mortality and life quality after tumor resection is necessary.

Pancreatic endocrine tumors with major vascular abutment, involvement, or encasement and indication for resection

BACKGROUND

Surgery for pancreatic endocrine tumors (PETs) with blood vessel involvement is controversial.

HYPOTHESIS

Resection of PETs with major blood vessel involvement can be beneficial.

DESIGN

The combined databases of the National Institutes of Health and Stanford University hospitals were queried.

MAIN OUTCOME MEASURES

Operation, pathologic condition, complications, and disease-free and overall survival.

RESULTS

Of 273 patients with PETs, 46 (17%) had preoperative computed tomography evidence of major vascular involvement. The mean size for the primary PET was 5.0 cm. The involved major vessel was as follows: portal vein (n = 20), superior mesenteric vein or superior mesenteric artery (n = 16), inferior vena cava (n = 4), splenic vein (n = 4), and heart (n = 2). Forty-two of 46 patients had a PET removed: 12 (27%) primary only, 30 (68%) with lymph nodes, and 18 (41%) with liver metastases. PETs were removed by either enucleation (n = 7) or resection (n = 35). Resections included distal or subtotal pancreatectomy in 23, Whipple in 10, and total in 2. Eighteen patients had concomitant liver resection: 10 wedge resection and 8 anatomic resections. Nine patients had vascular reconstruction: each had reconstruction of the superior mesenteric vein and portal vein, and 1 had concomitant reconstruction of the superior mesenteric artery. There were no deaths, but 12 patients had complications. Eighteen patients (41%) were immediately disease free, and 5 recurred with follow-up, leaving 13 (30%) disease-free long term. The 10-year overall survival was 60%. Functional tumors were associated with a better overall survival (P < .001), and liver metastases decreased overall survival (P < .001).

CONCLUSION

These findings suggest that surgical resection of PETs with vascular abutment/invasion and nodal or distant metastases is indicated.

Pancreas-protocol imaging at a high-volume center leads to improved preoperative staging of pancreatic ductal adenocarcinoma

BACKGROUND

High-quality preoperative cross-sectional imaging is vital to accurately stage patients with pancreatic ductal adenocarcinoma (PDAC). We hypothesized that imaging performed at a high-volume pancreatic cancer center with pancreatic imaging protocols more accurately stages patients compared with pre-referral imaging.

METHODS

We retrospectively reviewed data from all patients with PDAC who presented to the surgical oncology clinic at our institution between June 2005 and August 2009. Detailed preoperative imaging, staging, and operative data were collected for each patient.

RESULTS

A total of 230 patients with PDAC were identified, of which 169 had pre-referral imaging. Patients were selectively reimaged at our institution based on the quality and timing of imaging at the outside facility: 108 (47%) patients were deemed resectable, 54 (23.5%) were deemed borderline-resectable, and 68 (29.5%) were deemed unresectable. Of the resectable patients, 99 opted for resection. Eighty-two of those 99 patients underwent preoperative imaging at our institution, and of these 27% had unresectable disease at the time of surgery compared with 47% of patients who only had pre-referral imaging (p = 0.14). Reimaging altered staging and changed management in 56% of patients. Among that group were 55 patients, categorized as resectable on pre-referral imaging, who on repeat imaging were deemed to be borderline resectable (n = 27) or unresectable (n = 28).

CONCLUSIONS

Pancreas-protocol imaging at a high-volume center improves preoperative staging and alters management in a significant proportion of patients with PDAC who undergo pre-referral imaging. Thus, repeat imaging with pancreas protocols and dedicated radiologists is justified at high-volume centers.

Staging cancer of the pancreas

Pancreatic carcinoma is the fourth cause of death from cancer in the United States, with a survival rate at 5 years of less than 5%. About 60% of tumors originate at the head of the pancreas, 15% in the body, 5% in the tail; 20% are diffuse within the pancreas. This article discusses the imaging and staging of pancreatic cancer.