A comparison of pancreaticoduodenectomy with extended pancreaticoduodenectomy: A meta-analysis of 1909 patients

Contrast-enhanced CT radiomics combined with multiple machine learning algorithms for preoperative identification of lymph node metastasis in pancreatic ductal adenocarcinoma

Objectives

This research aimed to assess the value of radiomics combined with multiple machine learning algorithms in the diagnosis of pancreatic ductal adenocarcinoma (PDAC) lymph node (LN) metastasis, which is expected to provide clinical treatment strategies.

Methods

A total of 128 patients with pathologically confirmed PDAC and who underwent surgical resection were randomized into training (n=93) and validation (n=35) groups. This study incorporated a total of 13 distinct machine learning algorithms and explored 85 unique combinations of these algorithms. The area under the curve (AUC) of each model was computed. The model with the highest mean AUC was selected as the best model which was selected to determine the radiomics score (Radscore). The clinical factors were examined by the univariate and multivariate analysis, which allowed for the identification of factors suitable for clinical modeling. The multivariate logistic regression was used to create a combined model using Radscore and clinical variables. The diagnostic performance was assessed by receiver operating characteristic curves, calibration curves, and decision curve analysis (DCA).

Results

Among the 233 models constructed using arterial phase (AP), venous phase (VP), and AP+VP radiomics features, the model built by applying AP+VP radiomics features and a combination of Lasso+Logistic algorithm had the highest mean AUC. A clinical model was eventually constructed using CA199 and tumor size. The combined model consisted of AP+VP-Radscore and two clinical factors that showed the best diagnostic efficiency in the training (AUC = 0.920) and validation (AUC = 0.866) cohorts. Regarding preoperative diagnosis of LN metastasis, the calibration curve and DCA demonstrated that the combined model had a good consistency and greatest net benefit.

Conclusions

Combining radiomics and machine learning algorithms demonstrated the potential for identifying the LN metastasis of PDAC. As a non-invasive and efficient preoperative prediction tool, it can be beneficial for decision-making in clinical practice.

Chinese Society of Clinical Oncology (CSCO): Clinical guidelines for the diagnosis and treatment of pancreatic cancer

Pancreatic cancer is one of the leading causes of cancer-related mortality in both developed and developing countries. The incidence of pancreatic cancer in China accounts for about a quater of the global incidence, and the epidemiological characteristics and therapeutic strategies differ due to social, economic, cultural, environmental, and public health factors. Non-domestic guidelines do not reflect the clinicopathologic characteristics and treatment patterns of Chinese patients. Thus, in 2018, the Chinese Society of Clinical Oncology (CSCO) organized a panel of senior experts from all sub-specialties within the field of pancreatic oncology to compile the Chinese guidelines for the diagnosis and treatment of pancreatic cancer. The guidelines were made based on both the Western and Eastern clinical evidence and updated every one or two years. The experts made consensus judgments and classified evidence-based recommendations into various grades according to the regional differences, the accessibility of diagnostic and treatment resources, and health economic indexes in China. Here we present the latest version of the guidelines, which covers the diagnosis, treatment, and follow-up of pancreatic cancer. The guidelines might standardize the diagnosis and treatment of pancreatic cancer in China and will encourage oncologists to design and conduct more clinical trials about pancreatic cancer.

Safety and efficacy of TRIANGLE operation applied in pancreatic surgery: a protocol of the systematic review and meta-analysis

BACKGROUND

Pancreatic surgery is regarded as the only curative treatment for pancreatic cancer (PC). As the neoadjuvant therapy is applied widely nowadays, the proportion of patients with PC undergoing surgery also with locally advanced tumour findings has increased accordingly. Especially in these situations, a radical resection of all tumour tissues is challenging. A novel surgical strategy has been introduced recently to achieve this aim, namely the TRIANGLE operation which comprises the radical resection of all nerve and lymphatic tissue between coeliac artery, superior mesenteric artery and mesenteric-portal axis without including extended lymphadenectomy outside this area. Due to currently published studies, Triangle Operation is a safe and feasible procedure. However, this has not been systematically analysed to date. This systematic review and meta-analysis aim to evaluate surgical and postoperative outcomes of Triangle Operation in pancreatic surgery.

METHODS AND ANALYSIS

Pubmed, Web of Science and Cochrane Central Register of Controlled Trials in the Cochrane Library will be searched from inception until 31 December 2022. This study will include all articles comparing Triangle Operation versus non-Triangle Operation in pancreatic surgery to assess outcomes. The primary endpoints will be R0 resection rate and 1-year overall survival. The secondary endpoints will be delayed gastric emptying, postoperative pancreatic fistula, post pancreatectomy haemorrhages and reoperation incidence, overall complications, mortality and 3-year overall survival. The study selection, study quality assessment, data extraction and critical appraisal will be carried out by two reviewers. Inter-reviewer disagreements will be evaluated by discussion with a third reviewer. Besides, a subgroup analysis will be conducted focused on robotic surgery, laparoscopic surgery and open surgery in detail. Additionally, the Grading of Recommendations, Assessment, Development and Evaluations framework will be performed to evaluate the strength of evidence.

ETHICS AND DISSEMINATION

This systematic review and meta-analysis will not require ethical approval. Results will be published in a peer-reviewed scientific journal.

PROSPERO REGISTRATION NUMBER

CRD42021234721.

Surgical Complications in a Multicenter Randomized Trial Comparing Preoperative Chemoradiotherapy and Immediate Surgery in Patients With Resectable and Borderline Resectable Pancreatic Cancer (PREOPANC Trial)

OBJECTIVES

To investigate the effect of preoperative chemoradiotherapy on surgical complications in patients after pancreatic resection for (borderline-)resectable pancreatic cancer.

SUMMARY OF BACKGROUND DATA

Preoperative chemoradiotherapy is increasingly used in patients with (borderline-)resectable pancreatic cancer. concerns have been raised about the potential harmful effect of any preoperative therapy on the surgical complication rate after pancreatic resection.

METHODS

An observational analysis was performed within the multicenter randomized controlled PREOPANC trial (April 2013-July 2017). The trial randomly assigned (1:1) patients to preoperative chemoradiotherapy followed by surgery and the remaining adjuvant chemotherapy or to immediate surgery, followed by adjuvant chemotherapy. The main analysis consisted of a per-protocol approach. The endpoints of the present analyses were the rate of postoperative complications.

RESULTS

This study included 246 patients from 16 centers, of whom 66 patients underwent resection after preoperative therapy and 98 patients after immediate surgery. No differences were found regarding major complications (37.9% vs 30.6%, P=0.400), postpancreatectomy hemorrhage (9.1% vs 5.1%, P=0.352), delayed gastric emptying (21.2% vs 22.4%, P=0.930), bile leakage (4.5% vs 3.1%, P=0.686), intra-abdominal infections (12.1% vs 10.2%, P=0.800), and mortality (3.0% vs 4.1%, P=1.000). There was a significant lower incidence of postoperative pancreatic fistula in patients who received preoperative chemoradiotherapy (0% vs 9.2%, P=0.011).

CONCLUSIONS

Preoperative chemoradiotherapy did not increase the incidence of surgical complications or mortality and reduced the rate of postoperative pancreatic fistula after resection in patients with (borderline-)resectable pancreatic cancer.

Radiomics nomogram for the preoperative prediction of lymph node metastasis in pancreatic ductal adenocarcinoma

PURPOSE

To develop and validate a radiomics nomogram for the preoperative prediction of lymph node (LN) metastasis in pancreatic ductal adenocarcinoma (PDAC).

MATERIALS AND METHODS

In this retrospective study, 225 patients with surgically resected, pathologically confirmed PDAC underwent multislice computed tomography (MSCT) between January 2014 and January 2017. Radiomics features were extracted from arterial CT scans. The least absolute shrinkage and selection operator method was used to select the features. Multivariable logistic regression analysis was used to develop the predictive model, and a radiomics nomogram was built and internally validated in 45 consecutive patients with PDAC between February 2017 and December 2017. The performance of the nomogram was assessed in the training and validation cohort. Finally, the clinical usefulness of the nomogram was estimated using decision curve analysis (DCA).

RESULTS

The radiomics signature, which consisted of 13 selected features of the arterial phase, was significantly associated with LN status (p < 0.05) in both the training and validation cohorts. The multivariable logistic regression model included the radiomics signature and CT-reported LN status. The individualized prediction nomogram showed good discrimination in the training cohort [area under the curve (AUC), 0.75; 95% confidence interval (CI), 0.68-0.82] and in the validation cohort (AUC, 0.81; 95% CI, 0.69-0.94) and good calibration. DCA demonstrated that the radiomics nomogram was clinically useful.

CONCLUSIONS

The presented radiomics nomogram that incorporates the radiomics signature and CT-reported LN status is a noninvasive, preoperative prediction tool with favorable predictive accuracy for LN metastasis in patients with PDAC.

The Effect of Increase in Clinical Experience on Morbidity and Mortality After Pancreaticoduodenectomy Surgery

<b> Introduction:</b> Pancreaticoduodenectomy surgery is widely accepted and applied worldwide for periampullary tumors. Despite the decline in mortality rates from 40% to 3% with the advances in surgical technique, morbidity is still high (40–50%). </br></br> <b>Aim:</b> We aimed to investigate the effect of increased clinical experience on the length of hospital stay, morbidity, mortality, and survival after pancreaticoduodenectomy. </br></br> <b> Materials and methods:</b> The files of patients who underwent pancreaticoduodenectomy in our hospital between January 2007 and January 2018 were retrospectively reviewed and divided into four groups by years. Demographics, body mass index (BMI, kg/m2), medical history, preoperative biliary drainage application, surgical technique, histopathological features, postoperative morbidity, mortality, and survival were investigated. </br></br> <b> Results: </b> There was no difference between the groups in terms of age, gender, comorbid disease, history of biliary drainage, surgical technique, and operation time (P > 0.05). The rate of postoperative complications has decreased over the years (P = 0.01). According to the Clavien-Dindo scale, the complication severity decreased significantly over the years (P = 0.05). The overall survival of the patients increased by years (P = 0.03); the Early postoperative mortality rate decreased in the first month (<30 days) (P = 0.04). </br></br> <b> Conclusion:</b> With increased clinical experience, morbidity and mortality decrease, overall survival is prolonged after pancreaticoduodenectomy procedure.

Surgery for pancreatic cancer: current controversies and challenges

Two areas that remain the focus of improvement in pancreatic cancer include high post-operative morbidity and inability to uniformly translate surgical success into long-term survival. This narrative review addresses specific aspects of pancreatic cancer surgery, including neoadjuvant therapy, vascular resections, extended pancreatectomy, extent of lymphadenectomy and current status of minimally invasive surgery. R0 resection confers longer disease-free survival and overall survival. Vascular and adjacent organ resections should be undertaken after neoadjuvant therapy, only if R0 resection can be ensured based on high-quality preoperative imaging, and that too, with acceptable post-operative morbidity. Extended lymphadenectomy does not offer any advantage over standard lymphadenectomy. Although minimally invasive distal pancreatectomies offers some short-term benefits over open distal pancreatectomy, safety remains a concern with minimally invasive pancreatoduodenectomy. Strict adherence to principles and judicious utilization of surgery within a multimodality framework is the way forward.

3D Bioprinted cancer models: Revolutionizing personalized cancer therapy

After cardiovascular disease, cancer is the leading cause of death worldwide with devastating health and economic consequences, particularly in developing countries. Inter-patient variations in anti-cancer drug responses further limit the success of therapeutic interventions. Therefore, personalized medicines approach is key for this patient group involving molecular and genetic screening and appropriate stratification of patients to treatment regimen that they will respond to. However, the knowledge related to adequate risk stratification methods identifying patients who will respond to specific anti-cancer agents is still lacking in many cancer types. Recent advancements in three-dimensional (3D) bioprinting technology, have been extensively used to generate representative bioengineered tumor in vitro models, which recapitulate the human tumor tissues and microenvironment for high-throughput drug screening. Bioprinting process involves the precise deposition of multiple layers of different cell types in combination with biomaterials capable of generating 3D bioengineered tissues based on a computer-aided design. Bioprinted cancer models containing patient-derived cancer and stromal cells together with genetic material, extracellular matrix proteins and growth factors, represent a promising approach for personalized cancer therapy screening. Both natural and synthetic biopolymers have been utilized to support the proliferation of cells and biological material within the personalized tumor models/implants. These models can provide a physiologically pertinent cell-cell and cell-matrix interactions by mimicking the 3D heterogeneity of real tumors. Here, we reviewed the potential applications of 3D bioprinted tumor constructs as personalized in vitro models in anticancer drug screening and in the establishment of precision treatment regimens.

Efficacy of extended versus standard lymphadenectomy in pancreatoduodenectomy for pancreatic head adenocarcinoma. An update meta-analysis

BACKGROUND

Surgical resection is the only possible cure for pancreatic cancer, it remains controversial whether extend lymphadenectomy in pancreatoduodenectomy (EPD) is better than standard lymphadenectomy in pancreatoduodenectomy (SPD). The aim of this study was to compare the efficacy of EPD with SPD for pancreatic head adenocarcinoma.

METHODS

A specific search of online databases including PubMed, Web of Science, Embase, and Cochrane library was conducted from January 1990 to October 2018. Relative perioperative outcomes were synthesized. Single-arm meta-analysis was also performed.

RESULTS

A total of eight studies involving 687 (342 vs 345) patients were included for analysis in our study. The number of lymph nodes harvested [24.54 vs 13.29; weighted mean difference (WMD) -10.69, P = 0.000], operative time (469.84 min vs 354.85 min; WMD -99.09, P = 0.000), and diarrhea (postoperative three months) [45.1% vs 18.2%; odds radio (OR) 0.20, P = 0.014] were significantly higher in patients who underwent EPD than SPD. The perioperative complications (35% vs 28.8%; OR 0.79, P = 0.186), tumor size (3.27 cm vs 3.248 cm; WMD -0.11, P = 0.256), lymph node metastasis (66% vs 55.9%; OR 0.71, P = 0.105), and positive margin (10.4% vs 11.3%; OR 1.28, P = 0.392) were no significant differences between EPD group and SPD group. Extended lymphadenectomy in pancreatoduodenectomy dose not contribute to the overall survival of patients with adenocarcinoma of the pancreatic head [hazard ratio (HR) 0.95; 95% CI 0.78-1.15; P = 0.61].

CONCLUSION

The update meta-analysis shows that EPD failed to improve the overall survival, may even lead to increased morbidity.

Relationship Between Radiomics and Risk of Lymph Node Metastasis in Pancreatic Ductal Adenocarcinoma

OBJECTIVE

The objective of this study was to explore the exact relationship between the arterial radiomics score (rad-score) and lymph node (LN) metastasis in pancreatic ductal adenocarcinoma (PDAC).

METHODS

A total of 225 patients with pathologically confirmed PDAC who underwent multislice computed tomography within 1 month of resection from December 2016 to August 2017 were retrospectively studied. For each patient, 1029 radiomics features of arterial phase were extracted, which were reduced using the least absolute shrinkage and selection operator logistic regression algorithm. Multivariate logistic regression models were used to analyze the association between the arterial rad-score and LN metastasis.

RESULTS

Lymph node-negative and LN-positive patients accounted for 107 (47.56%) and 118 (52.44%) of the cohort, respectively. The rad-score, which consisted of 12 selected features of the arterial phase, was significantly associated with LN status (P < 0.05). Univariate analysis revealed that the arterial rad-score and T stage were independently and positively associated with risk of LN metastasis (P < 0.05). Multivariate analyses revealed a significant association between the arterial rad-score and the LN metastasis (P < 0.0001). Higher arterial rad-score was associated with LN metastasis (P for trend <0.0001).

CONCLUSIONS

The arterial rad-score is independently and positively associated with the risk of LN metastasis in PDAC.

Management of pancreatic head adenocarcinoma: From where to where?

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

Determining the optimal number of examined lymph nodes for accurate staging of pancreatic cancer: An analysis using the nodal staging score model

INTRODUCTION

The aim of this study was to determine the optimal number of examined lymph nodes (ELNs) for accurate staging of pancreatic cancer using the nodal staging score model.

MATERIALS AND METHODS

Clinicopathological data for patients with resected pancreatic cancer were collected from SEER database (development cohort [DC]) and Fudan University Shanghai Cancer Center database (validation cohort [VC]). Multivariable models were constructed to assess how the number of ELNs was associated with stage migration and overall survival (OS). Using the β-binomial distribution, we developed a nodal staging score model from the DC and tested it with the VC.

RESULTS

Both cohorts exhibited significant proportional increases from node-negative to node-positive disease (DC: odds ratio [OR], 1.047; P < 0.001; VC: OR, 1.035; P < 0.001) and improved OS (DC: hazard ratio [HR], 0.982; P < 0.001; VC: HR, 0.979; P < 0.001) as ELNs increased. Nodal staging scores escalated separately as ELNs increased for different tumor (T) stages, with plateaus at 16, 21, and 23 LNs (cut-offs) for T1, T2, and T3 tumors, respectively. Multivariable analysis indicated that examining more LNs than the corresponding cut-off value was a significant survival predictor (DC: HR, 0.813; P < 0.001; VC: HR, 0.696; P = 0.028).

CONCLUSION

The optimal number of ELNs for adequate staging of pancreatic cancer was related to T stage. We recommend examining at least 16, 21, and 23 LNs for T1, T2, and T3 tumors, respectively, as a nodal staging quality measure for both surgery and pathological analysis.

Accuracy of Nodal Positivity in Inadequate Lymphadenectomy in Pancreaticoduodenectomy for Pancreatic Ductal Adenocarcinoma: A Population Study Using the US SEER Database

Objectives: The optimal number of the examined lymph nodes (ELNs) in pancreaticoduodenectomy for pancreatic ductal adenocarcinoma has been widely studied. However, the accuracy of nodal positivity for the patients with inadequate lymphadenectomy is still unclear. The purpose of our study was to determine the accuracy of the number of positive nodes reported for patients with 1-3 positive nodes and the probability that 4 or more nodes could be positive along with tumor size and number of nodes examined. Methods: We obtained data on patients who underwent pancreaticoduodenectomy for resectable pancreatic ductal adenocarcinoma diagnosed during 2004-2013 from the US Surveillance, Epidemiology, and End Results registry. An mathematical model based on Hypergeometric Distribution and Bayes' Theorem was used to estimate the accuracy. Results: Among the 9,945 patients, 55.6% underwent inadequate lymphadenectomy. Of them, 1,842, 6,049, and 2,054 had T1, T2, and T3 stage disease, respectively. The accuracy of the number of observed positive nodes increased as the number of ELNs increased and the tumor size decreased. To rule out the possibility of N2 stage (4 and more positive nodes), there should be at least 13 ELNs for the patients with 1 observed positive lymph node and 14 for the patients with 2. Conclusion: Inadequate lymphadenectomy could result in underestimation of the N stage, and this would have adverse impact on recurrence, efficacy of postoperative treatment, and even overall survival. This model combined with the observed positive lymph nodes, the number of ELNs, and tumor size could provide a more accurate determination of nodal positivity of these patients.

Total mesopancreas excision for the treatment of pancreatic head cancer

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

Para-aortic node involvement is not an independent predictor of survival after resection for pancreatic cancer

AIM

To analyze the importance of para-aortic node status in a series of patients who underwent pancreaticoduodenectomy (PD) in a single Institution.

METHODS

Between January 2000 and December 2012, 151 patients underwent PD with para-aortic node dissection for pancreatic adenocarcinoma in our Institution. Patients were divided into two groups: patients with negative PALNs (PALNs-), and patients with metastatic PALNs (PALNs+). Pathologic factors, including stage, nodal status, number of positive nodes and lymph node ratio, invasion of para-aortic nodes, tumor’s grading, and radicality of resection were studied by univariate and multivariate analysis. Survival curves were constructed with Kaplan-Meier method and compared with Log-rank test: significance was considered as P < 0.05.

RESULTS

A total of 107 patients (74%) had nodal metastases. Median number of pathologically assessed lymph nodes was 26 (range 14-63). Twenty-five patients (16.5%) had para-aortic lymph node involvement. Thirty-three patients (23%) underwent R1 pancreatic resection. One-hundred forty-one patients recurred and died for tumor recurrence, one is alive with recurrence, and 9 are alive and free of disease. Overall survival was significantly influenced by grading (P = 0.0001), radicality of resection (P = 0.001), stage (P = 0.03), lymph node status (P = 0.04), para-aortic nodes metastases (P = 0.02). Multivariate analysis showed that grading was an independent prognostic factor for overall survival (P = 0.0001), while grading (P = 0.0001) and radicality of resection (P = 0.01) were prognostic parameters for disease-free survival. Number of metastatic nodes, node ratio, and para-aortic nodes involvement were not independent predictors of disease-free and overall survival.

CONCLUSION

In this experience, lymph node status and para-aortic node metastases were associated with poor survival at univariate analysis, but they were not independent prognostic factors.

Staging of pancreatic cancer based on the number of positive lymph nodes

BACKGROUND

The International Study Group on Pancreatic Surgery has stated that at least 12 lymph nodes should be evaluated for staging of pancreatic cancer. The aim of this population-based study was to evaluate whether the number of positive lymph nodes refines staging.

METHODS

Patients who underwent pancreatectomy for stage I-II pancreatic cancer between 2004 and 2012 were identified from the Surveillance, Epidemiology, and End Results database. The predictive value of the number of positive lymph nodes for survival was assessed by generalized receiver operating characteristic (ROC) curve analysis and propensity score-adjusted Cox regression analysis.

RESULTS

Some 5036 patients were included, with a median of 18 (i.q.r. 15-24) lymph nodes examined. Positive lymph nodes were found in 3555 patients (70·6 per cent). The median duration of follow-up was 15 (i.q.r. 8-28) months. ROC curve analysis revealed that two positive lymph nodes best discriminated overall survival. Patients with one or two positive lymph nodes (pN1a) and those with three or more positive lymph nodes (pN1b) had an increased risk of overall mortality compared with patients who were node-negative (pN0): hazard ratio (HR) 1·47 (95 per cent c.i. 1·33 to 1·64) and HR 2·01 (1·82 to 2·22) respectively. These findings were confirmed by propensity score-adjusted Cox regression analysis. The 5-year overall survival rates were 39·8 (95 per cent c.i. 36·5 to 43·3) per cent for patients with pN0, 21·0 (18·6 to 23·6) per cent for those with pN1a and 11·4 (9·9 to 13·3) per cent for patients with pN1b disease.

CONCLUSION

The number of positive lymph nodes in the resection specimen is a prognostic factor in patients with pancreatic cancer.

Does the Ileal Brake Contribute to Delayed Gastric Emptying After Pancreatoduodenectomy?

Delayed gastric emptying (DGE) represents a significant cause for morbidity following pancreatoduodenectomy (PD). At a time when no specific and universally effective therapy exists to treat these patients, elucidating other potential (preventable or treatable) mechanisms for DGE is important. The aim of the manuscript was to test the hypothesis that ileal brake contributes to DGE in PD patients receiving jejunal tube feeding by systematically reviewing experimental and clinical literature. A series of clinically relevant questions were framed related to the potential role of the ileal brake in development of DGE post-PD and formed the basis of targeted literature searches. A comprehensive search of major reference databases from January 1980 to June 2015 was carried out which included human and animal studies. The ileal brake is a feedback loop neurally mediated by the vagus and sympatho-adrenergic pathways and hormonally by gut peptides including glucagon-like peptide-1, peptide YY (PYY), and neurotensin. The most potent stimulus for this inhibitory reflex is intra-ileal fat. There is evidence to indicate the role of an inhibitory reflex (on gastric emptying) mediated by PYY and CCK which, in turn, are stimulated by nutrient delivery into the distal small intestine providing indirect support to the role of ileal brake in post-PD DGE. The ileal brake is a likely factor contributing to DGE post-PD. While there has been no study to directly test this hypothesis, there is compelling indirect evidence to support it. Designing a trial that would answer such a question appears to be the most appropriate way forward.

Factors predicting adequate lymph node yield in patients undergoing pancreatoduodenectomy for malignancy

Background

Most pancreatoduodenectomy resections do not meet the minimum of 12 lymph nodes recommended by the American Joint Committee on Cancer for accurate staging of periampullary malignancies. The purpose of this study was to investigate factors affecting the likelihood of adequate nodal yield in pancreatoduodenectomy specimens subject to routine pathological assessment.

Methods

Six hundred sixty-two patients subject to pancreatoduodenectomy between 1990 and 2013 for pancreatic, ampullary, and common bile duct cancers were reviewed. Predictors of yielding at least 12 lymph nodes were evaluated with a logistic regression model, and a survival analysis was carried out to verify the prognostic implications of nodal counts.

Results

The median number of evaluated nodes was 17 (interquartile range 11 to 25), and less than 12 lymph nodes were reported in surgical specimens of 179 (27 %) patients. Tumor diameter ≥20 mm (odds ratio [OR] 2.547, 95 % confidence interval [CI] 1.225 to 5.329, P = 0.013), lymph node metastases (OR 2.642, 95 % CI 1.378 to 5.061, P = 0.004), and radical lymphadenectomy (OR 5.566, 95 % CI 2.041 to 15.148, P = 0.01) were significant predictors of retrieving 12 or more lymph nodes. Lymph node counts did not influence the overall prognosis of the patients. However, a subgroup analysis carried out for individual cancer sites demonstrated that removing at least 12 lymph nodes is associated with better prognosis for pancreatic cancer.

Conclusions

Few variables affect adequate nodal yield in pancreatoduodenectomy specimens subject to routine pathological assessment. Considering the ambiguities related to the only modifiable factor identified, appropriate pathology training should be considered to increase nodal yield rather than more aggressive lymphatic dissection.

The Standardization of Pancreatoduodenectomy: Where Are We?

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

Advances in the Surgical Management of Resectable and Borderline Resectable Pancreas Cancer

Successful surgical resection offers the only chance for cure in patients with pancreatic cancer. However, pancreatic resection is feasible in less than 20% of the patients. In this review, the current state of surgical management of pancreatic cancer is discussed. The definition of resectability based on cross-sectional imaging and the technical aspects of surgery, including vascular resection and/or reconstruction, management of aberrant vascular anatomy and extent of lymphadenectomy, are appraised. Furthermore, common pancreatic resection-specific postoperative complications and their management are reviewed.

The lymphatic system and pancreatic cancer

This review summarizes current knowledge of the biology, pathology and clinical understanding of lymphatic invasion and metastasis in pancreatic cancer. We discuss the clinical and biological consequences of lymphatic invasion and metastasis, including paraneoplastic effects on immune responses and consider the possible benefit of therapies to treat tumors that are localized to lymphatics. A review of current techniques and methods to study interactions between tumors and lymphatics is presented.

Extended Versus Standard Lymphadenectomy for Pancreatic Head Cancer: Meta-Analysis of Randomized Controlled Trials

INTRODUCTION

The evidence for improved prognostic assessment and long-term survival for extended pancreatoduodenectomy (EPD) compared to standard pancreatoduodenectomy (SPD) in patients with carcinoma of the head of the pancreas has not been considered from only randomized controlled trials (RCTs).

METHODS

The aim of this study was to conduct a systematic review and meta-analysis of the outcomes comparing SPD and EPD in RCTs. Searches were performed on MEDLINE, Embase and Cochrane databases using MeSH keyword combinations: 'pancreatic cancer', 'pancreaticoduodenectomy', 'extended', 'randomized' and 'lymphadenectomy'. RCTs published up to 2014 were included. Overall post-operative survival, morbidity, 30-day mortality and length of hospital stay were the outcomes assessed.

RESULTS

Five eligible RCTs with 546 participants were included (EPD = 276 and SPD = 270). EPD was associated with a significantly higher number of excised lymph nodes (LNs) compared to SPD (mean difference = 15.73, 95% confidence interval (CI) = 9.41-22.04; P < 0.00001; I(2) = 88%). LN metastasis was detected in 58-68 and 55-70% of patients who had EPD and SPD, respectively. EPD did not improve overall survival (hazard ratio (HR) = 0.88, 95% CI = 0.75-1.03; P = 0.11) but did worsen post-operative morbidity compared to SPD (risk ratio (RR) = 1.23; 95% CI = 1.01-1.50; P = 0.004; I(2) = 9%). There were no differences in the 30-day mortality (RR = 0.81; 95% CI = 0.32-2.06; P = 0.66; I(2) = 0%) or length of hospital stay (mean difference = 1.39, 95% CI = -2.31 to 5.09; P = 0.46; I(2) = 67%).

CONCLUSION

SPD is associated with reduced morbidity, but equivalent long-term benefits compared to patients undergoing EPD.

Extent of lymphadenectomy to associate with pancreaticoduodenectomy in patients with pancreatic head cancer for better tumor staging

OBJECTIVES

To define the extent of lymphadenectomy to associate with surgery for pancreatic head cancer.

BACKGROUND

Pancreaticoduodenectomy with extended lymphadenectomy fails to prolong patient survival.

METHODS

Prospective randomized and nonrandomized controlled trials (RCTs and NRCTs), meta-analyses, retrospective reviews, consensus conferences and pre- and intraoperative diagnoses of lymph node (LN) metastases were retrieved. Standard and extended lymphadenectomies were reviewed, including their effects on postoperative complications, mortality rate and long-term survival. The minimum total number of LN examined (TNLE) for adequate tumor staging, and the incidence of metastasis to each LN station were also considered. A pros and cons analysis was performed on the removal of each LN station.

RESULTS

Eleven retrospective studies (2514 patients), five prospective NRCTs (545 patients), and five prospective RCTs (586 patients) described different lymphadenectomies, which obtained similar long-term results. Five meta-analyses showed they did not influence long-term survival. However, N status is an important component of tumor staging. The recommended minimum TNLE is 15. The percent incidence of metastasis to each LN station was calculated considering at least 385 and up to 3725 patients. Preoperative imaging and intraoperative exploration frequently fail to identify metastatic nodes. A pros and cons analysis suggests that lymph node status is better established removing the following LN stations: 6, 8a-p, 12a-b-c, 13a-b, 14a-b-c-d, 16b1, 17a-b. Metastasis to 16b1 LNs significantly worsens prognosis. Their removal and frozen section examination, before proceeding with resection, may contraindicate resection.

CONCLUSION

A standard lymphadenectomy demands an adequate TNLE and removal of the LN stations metastasizing more frequently, without increasing the surgical risk.

A meta-analysis of extended versus standard lymphadenectomy in patients undergoing pancreatoduodenectomy for pancreatic adenocarcinoma

BACKGROUND

Lymph node involvement in pancreatic adenocarcinoma is a key prognostic factor. Therefore, extending the number of lymph node stations excised in pancreatoduodenectomy may be beneficial to patients with pancreatic adenocarcinoma. This systematic review and meta-analysis examines the outcomes of extended versus standard lymphadenectomy in the published literature.

METHODS

A meta-analysis of randomized controlled trials (RCTs) comparing extended with standard lymphadenectomy in patients undergoing pancreatoduodenectomy for pancreatic adenocarcinoma was performed. Perioperative outcomes were assessed as pooled odds ratios (ORs) and weighted mean differences. Overall survival was analysed for patients with positive and negative lymph nodes. Results were reported according to the PRISMA statement.

RESULTS

Five RCTs were included, accounting for 724 patients. Extended lymphadenectomy was associated with greater operative time [mean difference: 63 min, 95% confidence interval (CI) 29-96; P < 0.001], increased need for blood transfusions (mean difference: 0.20, 95% CI 0.01-0.30; P = 0.030) and greater postoperative morbidity (OR 1.5, 95% CI 1.25-2.00; P = 0.030), as well as with prolonged diarrhoea after circumferential autonomic nerve dissection around major vessels (OR 12.2, 95% CI 5.3-28.5; P < 0.001). Median survival was similar across the groups in the whole cohort, as well as in subgroups of patients with, respectively, positive and negative lymph nodes.

CONCLUSIONS

Extended lymphadenectomy has a harmful impact on patients undergoing oncological pancreatoduodenectomy compared with standard lymphadenectomy.

Pathophysiology after pancreaticoduodenectomy

Pancreaticoduodenectomy (PD) will result in removal of important multiorgans in upper intestinal tract and subsequently secondary physiologic change. In the past, surgeons just focused on the safety of surgical procedure; however, PD is regarded as safe and widely applied to treatment of periampullary lesions. Practical issues after PD, such as, effect of duodenectomy, metabolic surgery-like effect, alignment effect of gastrointestinal continuity, and non-alcoholic fatty liver disease were summarized and discussed.

[Surgery for pancreatic cancer: Evidence-based surgical strategies]

Pancreatic cancer surgery represents a challenge for surgeons due to its technical complexity, the potential complications that may appear, and ultimately because of its poor survival. The aim of this article is to summarize the scientific evidence regarding the surgical treatment of pancreatic cancer in order to help surgeons in the decision making process in the management of these patients .Here we will review such fundamental issues as the need for a biopsy before surgery, the type of pancreatic anastomosis leading to better results, and the need for placement of drains after pancreatic surgery will be discussed.

Mesopancreas: A boundless structure, namely the rationale for dissection of the paraaortic area in pancreaticoduodenectomy for pancreatic head carcinoma

This review highlights the rationale for dissection of the 16a2 and 16b1 paraaortic area during pancreaticoduodenectomy (PD) for carcinoma of the head of the pancreas. Recent advances in surgical anatomy of the mesopancreas indicate that the retropancreatic area is not a single entity with well defined boundaries but an anatomical site of embryological fusion of peritoneal layers, and that continuity exists between the neuro lymphovascular adipose tissues of the retropancreatic and paraaortic areas. Recent advances in surgical pathology and oncology indicate that, in pancreatic head carcinoma, the mesopancreatic resection margin is the primary site for R1 resection, and that epithelial-mesenchymal transition-related processes involved in tumor progression may impact on the prevalence of R1 resection or local recurrence rates after R0 surgery. These concepts imply that mesopancreas resection during PD for pancreatic head carcinoma should be extended to the paraaortic area in order to maximize retropancreatic clearance and minimize the likelihood of an R1 resection or the persistence of residual tumor cells after R0 resection. In PD for pancreatic head carcinoma, the rationale for dissection of the paraaortic area is to control the spread of the tumor cells along the mesopancreatic resection margin, rather than to control or stage the nodal spread. Although mesopancreatic resection cannot be considered “complete” or “en bloc”, it should be “extended as far as possible” or be “maximal”, including dissection of 16a2 and 16b1 paraaortic areas.

Time-related changes in the prognostic significance of the total number of examined lymph nodes in node-negative pancreatic head cancer

BACKGROUND AND OBJECTIVES

The aim of study was to assess time trends in the association between the total number of lymph nodes examined (TNLE) and survival in patients operated for adenocarcinoma of the head of pancreas.

METHODS

Patients operated for node-negative adenocarcinoma of the head of pancreas between 1988 and 2007 were identified from the Surveillance, Epidemiology and End Results (SEER) database. Patients diagnosed between 1988 and 2002 were compared to those diagnosed between 2003 and 2007.

RESULTS

A total of 3,406 patients were included. Although TNLE was associated with survival, the effect was not uniform. Compared to patients with >12 TNLE, survival decreased with lower TNLE (4-12 TNLE: hazard ratio [HR] 1.27, 95% CI 1.10-1.46; <4 TNLE: HR 1.39, 95% CI 1.20-1.60) among patients diagnosed between 1988 and 2002. In contrast, for those diagnosed between 2003 and 2007, while there was decreased survival for those with <4 nodes (HR 1.44, 95% CI 1.22-1.71), no effect was seen for patients with TNLE 4-12 (HR 0.98, 95% CI 0.85-1.14).

CONCLUSION

The prognostic significance of the TNLE in patients operated for adenocarcinoma of the head of the pancreas is not constant over time.

Role of extended lymphadenectomy in the treatment of pancreatic head adenocarcinoma: review and meta-analysis

BACKGROUND

Extended lymph node dissection has been established as the method of choice in the treatment of many digestive malignancies, but its role in the treatment of adenocarcinoma of the pancreas remains controversial.

OBJECTIVES

The goal is to evaluate the role of extended lymph node dissection in pancreatic head adenocarcinoma and to review how it affects survival, morbidity, mortality and post-operative quality of life.

METHODS

A computerized search was made of the Medline database from January 1973 to October 2012. Fifteen non-duplicated studies, four randomized and 11 non-randomized, comparing extended radical pancreaticoduodenectomy (ERP) and standard pancreaticoduodenectomy were reviewed. Five-year overall survivals were compared using the MetaXL software in eight of these studies, where the necessary data were available.

RESULTS

The 5-year survival after ERP ranged from 6 to 33.4% and the local recurrence incidence from 8 to 36.1%, while the incidence of severe diarrhoea, one of the main complications, ranged from 10.8 to 42.4%. Meta-analysis showed that there was no significant difference in the 5-year overall survival (95% confidence interval (CI): -0.21-0.20, Z=0.07, P=0.94) for randomized control trials, (95% CI: -0.51-0.02, Z=1.85, P=0.07) for non-randomized control trials and (95% CI: -0.26-0.06, Z=1.20, P=0.23) for all the studies.

CONCLUSIONS

Although ERP is a safe procedure, it did not offer a significant improvement in survival, while at the same time leading to an increased incidence of severe diarrhoea for at least 1 year, thus leaving the standard pancreaticoduodenectomy as the surgical method of choice for the treatment of pancreatic head adenocarcinoma.

Definition of a standard lymphadenectomy in surgery for pancreatic ductal adenocarcinoma: a consensus statement by the International Study Group on Pancreatic Surgery (ISGPS)

BACKGROUND

The lymph node (Ln) status of patients with resectable pancreatic ductal adenocarcinoma is an important predictor of survival. The survival benefit of extended lymphadenectomy during pancreatectomy is, however, disputed, and there is no true definition of the optimal extent of the lymphadenectomy. The aim of this study was to formulate a definition for standard lymphadenectomy during pancreatectomy.

METHODS

During a consensus meeting of the International Study Group on Pancreatic Surgery, pancreatic surgeons formulated a consensus statement based on available literature and their experience.

RESULTS

The nomenclature of the Japanese Pancreas Society was accepted by all participants. Extended lymphadenectomy during pancreatoduodenectomy with resection of Ln's along the left side of the superior mesenteric artery (SMA) and around the celiac trunk, splenic artery, or left gastric artery showed no survival benefit compared with a standard lymphadenectomy. No level I evidence was available on prognostic impact of positive para-aortic Ln's. Consensus was reached on selectively removing suspected Ln's outside the resection area for frozen section. No consensus was reached on continuing or terminating resection in cases where these nodes were positive.

CONCLUSION

Extended lymphadenectomy cannot be recommended. Standard lymphadenectomy for pancreatoduodenectomy should strive to resect Ln stations no. 5, 6, 8a, 12b1, 12b2, 12c, 13a, 13b, 14a, 14b, 17a, and 17b. For cancers of the body and tail of the pancreas, removal of stations 10, 11, and 18 is standard. Furthermore, lymphadenectomy is important for adequate nodal staging. Both pancreatic resection in relatively fit patients or nonresectional palliative treatment were accepted as acceptable treatment in cases of positive Ln's outside the resection plane. This consensus statement could serve as a guide for surgeons and researchers in future directives and new clinical studies.

Pancreatic cancer organotypics: High throughput, preclinical models for pharmacological agent evaluation

Pancreatic cancer carries a terrible prognosis, as the fourth most common cause of cancer death in the Western world. There is clearly a need for new therapies to treat this disease. One of the reasons no effective treatment has been developed in the past decade may in part, be explained by the diverse influences exerted by the tumour microenvironment. The tumour stroma cross-talk in pancreatic cancer can influence chemotherapy delivery and response rate. Thus, appropriate preclinical in vitro models which can bridge simple 2D in vitro cell based assays and complex in vivo models are required to understand the biology of pancreatic cancer. Here we discuss the evolution of 3D organotypic models, which recapitulare the morphological and functional features of pancreatic ductal adenocarcinoma (PDAC). Organotypic cultures are a valid high throughput preclinical in vitro model that maybe a useful tool to help establish new therapies for PDAC. A huge advantage of the organotypic model system is that any component of the model can be easily modulated in a short time-frame. This allows new therapies that can target the cancer, the stromal compartment or both to be tested in a model that mirrors the in vivo situation. A major challenge for the future is to expand the cellular composition of the organotypic model to further develop a system that mimics the PDAC environment more precisely. We discuss how this challenge is being met to increase our understanding of this terrible disease and develop novel therapies that can improve the prognosis for patients.

Extended pancreatectomy in pancreatic ductal adenocarcinoma: definition and consensus of the International Study Group for Pancreatic Surgery (ISGPS)

BACKGROUND

Complete macroscopic tumor resection is one of the most relevant predictors of long-term survival in pancreatic ductal adenocarcinoma. Because locally advanced pancreatic tumors can involve adjacent organs, "extended" pancreatectomy that includes the resection of additional organs may be needed to achieve this goal. Our aim was to develop a common consistent terminology to be used in centers reporting results of pancreatic resections for cancer.

METHODS

An international panel of pancreatic surgeons working in well-known, high-volume centers reviewed the literature on extended pancreatectomies and worked together to establish a consensus on the definition and the role of extended pancreatectomy in pancreatic cancer.

RESULTS

Macroscopic (R1) and microscopic (R0) complete tumor resection can be achieved in patients with locally advanced disease by extended pancreatectomy. Operative time, blood loss, need for blood transfusions, duration of stay in the intensive care unit, and hospital morbidity, and possibly also perioperative mortality are increased with extended resections. Long-term survival is similar compared with standard resections but appears to be better compared with bypass surgery or nonsurgical palliative chemotherapy or chemoradiotherapy. It was not possible to identify any clear prognostic criteria based on the specific additional organ resected.

CONCLUSION

Despite increased perioperative morbidity, extended pancreatectomy is warranted in locally advanced disease to achieve long-term survival in pancreatic ductal adenocarcinoma if macroscopic clearance can be achieved. Definitions of extended pancreatectomies for locally advanced disease (and not distant metastatic disease) are established that are crucial for comparison of results of future trials across different practices and countries, in particular for those using neoadjuvant therapy.

Prognostic value of the lymph node ratio after resection of periampullary carcinomas

BACKGROUND

Data have indicated that the lymph node ratio (LNR) may be a better prognostic indicator than lymph node status in pancreatic cancer.

OBJECTIVES

To analyse the value of the LNR in patients undergoing resection for periampullary carcinomas.

METHODS

A cut off value of 0.2 was assigned to the LNR in accordance with published studies. The impact of histopathological factors including a LNR was analysed using Kaplan-Meier and Cox regression methods.

RESULTS

In total, 551 patients undergoing a resection (January 2000 to December 2010) were analysed. The median lymph node yield was 15, and 198 (34%) patients had a LNR > 0.2. In patients with a LNR of > 0.2, the median overall survival (OS) was 18 versus 33 months in patients with an LNR < 0.2 (P < 0.001). Univariate analysis demonstrated a LNR > 0.2, T and N stage, vascular or perineural invasion, grade and resection margin status to be significantly associated with OS. On multivariate analysis, only a LNR > 0.2, vascular or perineural invasion and margin positivity remained significant. In N1 disease, a LNR was able to distinguish survival in patients with a similar lymph node burden, and correlated with more aggressive tumour pathological variables.

CONCLUSION

A LNR > 0.2, and not lymph note status, is an independent prognostic factor for OS indicating the LNR should be utilized in outcome stratification.

Serum level of Ca 19-9 increases ability of IgG4 test to distinguish patients with autoimmune pancreatitis from those with pancreatic carcinoma

BACKGROUND

Autoimmune pancreatitis (AIP) is often difficult to distinguish from pancreatic carcinoma or other pancreatobiliary diseases. High serum levels of carbohydrate antigen 19-9 (Ca 19-9) are indicative of malignancies, whereas high levels of immunoglobulin (Ig)G4 (>1.4 g/l) are characteristic of AIP. We investigated whether serum levels of these proteins can differentiate between these diseases.

METHODS

We measured levels of Ca 19-9 and IgG4 in serum samples from 33 patients with AIP, 53 with pancreatic carcinoma, and 145 with other pancreatobiliary disorders. We determined cut-off levels for each assay. Logistic regression analysis was used to evaluate combined data on Ca 19-9, IgG4, and bilirubin levels.

RESULTS

Low levels of Ca 19-9 were independently associated with AIP, compared with pancreatic adenocarcinoma [odds ratio (OR) 0.28; 95% confidence interval (CI) 0.13-0.59; p = 0.0001]. Using an upper level of 74 U/ml, the assay for Ca 19-9 identified patients with AIP with 73% sensitivity and 74% specificity. Using a lower level of 2.6 g/l, the assay for IgG4 identified these patients with 70% sensitivity and 100% specificity. Combining data, levels of Ca 19-9 < 74 U/ml and IgG4 > 1.0 g/l identified patients with AIP with 94% sensitivity and 100 % specificity.

CONCLUSIONS

Patients with AIP have lower levels of Ca 19-9 than those patients with pancreatic carcinoma. Measurement of either the Ca 19-9 or the IgG4 level alone are not accurate enough for diagnosis. However, the combination of Ca 19-9 < 74 U/ml and IgG4 > 1.0 g/l distinguishes patients with AIP from those patients with pancreatic carcinoma with 94% sensitivity and 100% specificity.

Standard and extended lymphadenectomy for adenocarcinoma of the pancreatic head: a meta-analysis and systematic review

BACKGROUND AND AIM

Although some retrospective studies have recommended that pancreaticoduodenectomy with extended lymphadenectomy might improve the survival of patients with adenocarcinoma of the head of the pancreas, the procedure remains controversial.

METHODS

Using PubMed, EMBASE, and The Cochrane Library databases, a systematic literature review was performed to identify randomized, controlled trials comparing standard and extended lymphadenectomy in pancreaticoduodenectomy for adenocarcinoma of the head of the pancreas.

RESULTS

Four trials including 423 patients satisfied the inclusion criteria. Extended lymphadenectomy failed to improve the overall survival of patients with adenocarcinoma of the head of the pancreas (hazard ratio 1.09; 95% confidence interval 0.84-1.41; P = 0.51). Additionally, postoperative mortality and morbidity were comparable between the standard and extended groups, while extended lymphadenectomy was associated with poor quality of life within 1 year after the operation.

CONCLUSIONS

Extended lymphadenectomy do not benefit overall survival. Considering the poor quality of life associated with extended lymphadenectomy, pancreaticoduodenectomy with standard lymphadenectomy is suitable for patients with adenocarcinoma of the head of the pancreas.

Meta-analysis of the efficacy of pancreatoduodenectomy with extended lymphadenectomy in the treatment of pancreatic cancer

Background

The purpose of this meta-analysis is to compare the efficacy of pancreatoduodenectomy (PD) with extended lymphadenectomy (PD/ELND) versus standard PD in the treatment of pancreatic cancer, with the hope of providing evidence for clinical practice.

Methods

The retrieval of relevant literature published before September 2012 was carried out on PubMed, Medline, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) by computer. Information was extracted according to Cochrane systematic review methods, and analyzed using software Stata 11.0.

Results

Five prospective randomized controlled trials (RCTs) were included in this meta-analysis of 555 cases (278 in the PD/ELND group and 277 in the standard PD group). The PD/ELND group showed a significantly lower 3-year survival rate (relative risk (RR) = 1.46, 95% confidence interval (CI) 1.03 to approximately 2.06, P = 0.034), prolonged operative time (weighted mean difference WMD = −1.03, 95% CI −1.96 to approximately −0.10, P = 0.029) and higher incidence of postoperative complications (RR = 0.56, 95% CI 0.42 to approximately 0.77, P = 0.000) by comparing with standard PD group. Besides, no significant difference was observed in the 1-year survival rate (RR = 0.87, 95% CI 0.60 to approximately 1.25, P = 0.69), 5-year survival rate (RR = 1.04, 95% CI 0.68 to approximately 1.58, P = 0.854), postoperative mortality (RR = 1.14, 95% CI 0.43 to approximately 3.00, P = 0.789), length of stay (WMD = −0.32, 95% CI −2.57 to approximately 1.94 , P = 0.784) and the amount of blood transfusions (WMD = −0.14, 95% CI −0.36 to approximately 0.08, P = 0.213).

Conclusions

PD/ELND does not have an advantage over standard PD in the survival rate for patients with pancreatic cancer, but does increase operative time and incidences of postoperative complications.

Pancreatic Cancer: Current Options for Diagnosis, Staging and Therapeutic Management

BACKGROUND

Pancreatic cancer is characterized by frequently delayed diagnosis and aggressive tumor growth which hampers most of the current treatment modalities. This review aims to summarize the available evidence about the diagnostic and therapeutic aspects of resectable and non-resectable pancreatic cancer therapy.

SUMMARY

Embedded in the concept of multimodal therapy, surgery plays the central role in the treatment of pancreatic cancer. With advantageous tumor characteristics and complete tumor resection as the most relevant positive prognostic factors, the detection of premalignant or early invasive lesions combined with safe and oncologic adequate surgery is the major therapeutic aim. Most pancreatic adenocarcinomas are locally advanced or metastatic when diagnosed and need to be treated by the combination of surgery and (radio)chemotherapy or by palliative chemotherapy.

Clinical necessity of the immunohistochemical reassessment of para-aortic lymph nodes in resected pancreatic ductal adenocarcinoma

Para-aortic lymph node (PALN) metastasis is widely regarded as a systemic disease in cancer. Undetected PALN micrometastases during routine hematoxylin and eosin (HE) staining may be a cause of poor prognosis following a potentially curative pancreatectomy for pancreatic cancer. In the present study, paraffin-embedded PALN tissue blocks from 99 patients who underwent a pancreatectomy were re-evaluated by immunohistochemical staining using cytokeratin (CK)-19. Patients with PALN metastasis were summarized according to the clinicopathological data. A total of 484 PALNs (median, 4.9 nodes per patient; range, 1–19) were evaluated. PALN metastases were revealed in eight patients (8.1%) by routine HE staining of frozen section biopsies and in one patient (1.0%) by HE staining of a permanent section. Only one patient (1.0%) demonstrated micrometastasis by IHC; this patient did not display any adverse pathological characteristics and had a relatively favorable survival period of 41 months. The present study concluded that an additional reassessment for micrometastasis in PALNs using CK-19 immunohistochemistry (IHC) is not a viable method for determining the survival outcome. A careful examination of a frozen section biopsy is sufficient for attempting curative surgery.

Pancreatic surgery: beyond the traditional limits

Pancreatic cancer is one of the five leading causes of cancer death for both males and females in the western world. More than 85 % pancreatic tumors are of ductal origin but the incidence of cystic tumors such as intrapapillary mucinous tumors (IPMN) or mucinous cystic tumors (MCN) and other rare tumors is rising. Complete surgical resection of the tumor is the mainstay of any curative therapeutic approach, however, up to 40 % of patients with potentially resectable pancreatic cancer are not offered surgery. This is despite 5-year survival rates of up to 40 % or even higher in selected patients depending on tumor stage and histology. Standard procedures for pancreatic tumors include the Kausch-Whipple- or pylorus-preserving Whipple procedure, and the left lateral pancreatic resection (often with splenectomy), and usually include regional lymphadenectomy. More radical or extended pancreatic operations are becoming increasingly utilised however and we examine the data available for their role. These operations include major venous and arterial resection, multivisceral resections and surgery for metastatic disease, or palliative pancreatic resection. Portal vein resection for local infiltration with or without replacement graft is now well established and does not deleteriously affect perioperative morbidity or mortality. Arterial resection, however, though often technically feasible, has questionable oncologic impact, is not without risk and is usually reserved for isolated cases. The value of extended lymphadenectomy is frequently debated; the recent level I evidence demonstrates no advantage. Multivisceral resections, i.e. tumors, often in the tail of the pancreas, with invasion of the colon or stomach or other surrounding tissues, while associated with an increased morbidity and a longer hospital stay, do however show comparable mortality-and survival rates to those without such infiltration and therefore should be performed if technically feasible. Routine resection for metastatic disease however does not seem to show any advantage over palliative treatment but may be an option in selected patients with easily removable metastases. In conclusion pancreatic surgery beyond the traditional limits is established in tumors infiltration the venous system and may be a considered approach in selected patients with locally infiltrating pancreatic cancer or metastasis.

Integration of radiation oncology with surgery as combined-modality treatment

Integration of surgery and radiation (external beam, EBRT; intraoperative, IORT) has become more routine for patients with locally advanced primary cancers and those with local-regional relapse. This article discusses patient selection and treatment from a more general perspective, followed by a discussion of patient selection and treatment factors in select disease sites (pancreas cancer, colorectal cancer, retroperitoneal soft-tissue sarcomas). Outcomes with combined modality treatment (surgery, EBRT alone or with concurrent chemotherapy, IORT) are discussed. The ultimate in contemporary integration of radiation and surgery is found in patients who are candidates for surgery plus both EBRT and IORT.

Prognostic relevance of number and ratio of metastatic lymph nodes in resected pancreatic, ampullary, and distal bile duct carcinomas

BACKGROUND

Lymph node ratio (LNR) may be more useful than nodal (N) status in prognostic subclassification of adenocarcinomas after pancreatoduodenectomy. Ampullary (AC), biliary (DBC), and pancreatic (PC) adenocarcinomas are biologically distinct, and nodal involvement may have different prognostic importance among these separate cancers.

METHODS

We included 179 consecutive pancreatoduodenectomies for PC, AC, or DBC, and performed standardized histopathologic evaluation, including prospective registration and retrospective reevaluation of the cancer origin. Associations between histopathologic variables and LNR, N status, and number of metastatic nodes were evaluated. Unadjusted and adjusted survival analysis was performed.

RESULTS

Overall 5 year survival was 6% for PC (n=72), 26% for DBC (n=46), and 46% for AC (n=61). Lymph node involvement was more frequent in PC (75%) than in AC (48%) and DBC (57%). In PC, N status did not discriminate between prognostic groups (N1 vs. N0; p=0.31). However, increasing LNR was associated with poorer survival in unadjusted analysis, as well as when adjusting for margin involvement, degree of differentiation, and tumor diameter (p=0.032; hazard ratio 1.87, 95% confidence interval 1.06-3.31). In AC and DBC, N status clearly discriminated between subgroups of patients with different long-term survival in unadjusted and adjusted survival analysis (N1 vs. N0; p<0.001), whereas number of metastatic nodes and LNR did not predict survival among node-positive resections.

CONCLUSIONS

The predictive value of nodal involvement depends on the type of cancer within the pancreatic head. In AC and DBC, N status adequately discriminates between good and poor prognosis. In PC, LNR may be more powerful in prognostic subclassification.

Recurrence after surgical resection of gastrinoma: who, when, where and why?

BACKGROUND

Surgery prolongs survival in patients with gastrinomas, but postoperative recurrences are frequent and controversies still exist about the optimal surgical procedures.

AIM

The aim of this study is to analyze biological and morphological recurrences and to search for risk factors.

PATIENTS AND METHODS

Between 1990 and 2008, 22 patients (five with multiple endocrine neoplasia type 1) who underwent curative resection for gastrinoma were evaluated every 6 months for biological and morphological recurrences. All patients were disease-free postresection.

RESULTS

The median postoperative follow-up was 37 months (range, 7-204 months). A biological recurrence was observed in 59% of cases, after a median time of 16.5 months (range, 7-90 months). A morphological recurrence was reported in 32% of cases, in the liver (86%) or lymph nodes (43%), after a median time of 21 months (range, 8-91 months). The median delay between biological and morphological recurrence was 3 months (range, 0-69 months). At recurrence, all patients were offered a second treatment (surgical resection in 71% of cases). One and 5 year overall survival were 100 and 76%, respectively. One and 5 year biological disease-free survival (DFS) were 76 and 27%, respectively. One and 5 year morphological DFS were 90 and 62%, respectively. Tumor size of at least 20 mm (P=0.008) and pancreatic location (P=0.04) of the primary tumor had significant effect on morphological DFS. Overall survival was significantly lower in patients with primary tumor of at least 20 mm (P=0.01).

CONCLUSION

(a) Recurrence occurs in nearly two out of three patients operated upon for gastrinoma, most often detected through biological tests; (b) lymph nodes and liver are the most frequent sites of relapse and patients benefit from second treatment; (c) risk factors for recurrences are as follows: size of at least 20 mm; and the pancreatic location of the primary tumor.

Surgery for pancreatic carcinoma: state of the art

Carcinoma of the pancreas remains a malignancy with a generally dismal outcome owing to the delayed presentation of the disease. To date, surgery affords the best outcomes when a complete resection can be achieved. Improvements in imaging, surgical techniques and adjuvant therapies are perceived advancements in the management of this cancer. This article reviews the latest evidence in terms of the diagnosis and management of pancreatic cancer.

Prevalence of autoimmune pancreatitis and other benign disorders in pancreatoduodenectomy for presumed malignancy of the pancreatic head

BACKGROUND

Occasionally patients undergoing resection for presumed malignancy of the pancreatic head are diagnosed postoperatively with benign disease. Autoimmune pancreatitis (AIP) is a rare disease that mimics pancreatic cancer. We aimed to determine the prevalence of benign disease and AIP in patients who underwent pancreatoduodenectomy (PD) over a 9-year period, and to explore if and how surgery could have been avoided.

METHODS

All patients undergoing PD between 2000 and 2009 in a tertiary referral centre were analyzed retrospectively. In cancer-negative cases, postoperative diagnosis was reassessed. Preoperative index of suspicion of malignancy was scored as non-specific, suggestive, or high. In AIP patients, diagnostic criteria systems were checked.

RESULTS

A total of 274 PDs were performed for presumed malignancy. The prevalence of benign disease was 8.4 %, overall prevalence of AIP was 2.6 %. Based on preoperative index of suspicion of malignancy, surgery could have been avoided in 3 non-AIP patients. All AIP patients had sufficient index to justify surgery. If diagnostic criteria would have been checked; however, surgery could have been avoided in one to five AIP patients.

CONCLUSIONS

The prevalence of benign disease in patients who underwent PD for presumed malignancy was 8.4 %, nearly one-third attributable to AIP. Although misdiagnosis of AIP as carcinoma is a problem of limited quantitative importance, every effort to establish the correct diagnosis should be undertaken considering the major therapeutic consequences. IgG4 measurement and systematic use of diagnostic criteria systems are recommended for every candidate patient for PD when there is no histological proof of malignancy.