Pancreatic cancer: advances in treatment, results and limitations

Establishment of prediction model for mortality risk of pancreatic cancer: a retrospective study

BACKGROUND AND AIM

Pancreatic cancer possesses a high prevalence and mortality rate among other cancers. Despite the low survival rate of this cancer type, the early prediction of this disease has a crucial role in decreasing the mortality rate and improving the prognosis. So, this study.

MATERIALS AND METHODS

In this retrospective study, we used 654 alive and dead PC cases to establish the prediction model for PC. The six chosen machine learning algorithms and prognostic factors were utilized to build the prediction models. The importance of the predictive factors was assessed using the relative importance of a high-performing algorithm.

RESULTS

The XG-Boost with AU-ROC of 0.933 (95% CI= [0.906-0.958]) and AU-ROC of 0.836 (95% CI= [0.789-0.865] in internal and external validation modes were considered as the best-performing model for predicting the mortality risk of PC. The factors, including tumor size, smoking, and chemotherapy, were considered the most influential for prediction.

CONCLUSION

The XG-Boost gained more performance efficiency in predicting the mortality risk of PC patients, so this model can promote the clinical solutions that doctors can achieve in healthcare environments to decrease the mortality risk of these patients.

In Situ Immunofluorescence Imaging of Vital Human Pancreatic Tissue Using Fiber-Optic Microscopy

Purpose

Surgical resection is the only curative option for pancreatic carcinoma, but disease-free and overall survival times after surgery are limited due to early tumor recurrence, most often originating from local microscopic tumor residues (R1 resection). The intraoperative identification of microscopic tumor residues within the resection margin in situ could improve surgical performance. The aim of this study was to evaluate the effectiveness of fiber-optic microscopy for detecting microscopic residues in vital pancreatic cancer tissues. Experimental Design. Fresh whole-mount human pancreatic tissues, histological tissue slides, cell culture, and chorioallantoic membrane xenografts were analyzed. Specimens were stained with selected fluorophore-conjugated antibodies and studied using conventional wide-field and self-designed multicolor fiber-optic fluorescence microscopy instruments.

Results

Whole-mount vital human tissues and xenografts were stained and imaged using an in situ immunofluorescence protocol. Fiber-optic microscopy enabled the detection of epitope-based fluorescence in vital whole-mount tissue using fluorophore-conjugated antibodies and enabled visualization of microvascular, epithelial, and malignant tumor cells. Among the selected antigen-antibody pairs, antibody clones WM59, AY13, and 9C4 were the most promising for fiber-optic imaging in human tissue samples and for endothelial, tumor and epithelial cell detection.

Conclusions

Fresh dissected whole-mount tissue can be stained using direct exposure to selected antibody clones. Several antibody clones were identified that provided excellent immunofluorescence imaging of labeled structures, such as endothelial, epithelial, or EGFR-expressing cells. The combination of in situ immunofluorescence staining and fiber-optic microscopy visualizes structures in vital tissues and could be proposed as an useful tool for the in situ identification of residual tumor mass in patients with a high operative risk for incomplete resection.

Identifying Optimal Candidates for Primary Tumor Resection Among Metastatic Pancreatic Cancer Patients: A Population-Based Predictive Model

BACKGROUND

There is a controversy about whether surgery should proceed among metastatic pancreatic cancer (mPC) patients. A survival benefit was observed in mPC patients who underwent primary tumor resection; however, determining which patients would benefit from surgery is complex. For this purpose, we created a model to identify mPC patients who may benefit from primary tumor excision.

METHODS

Patients with mPC were extracted from the Surveillance, Epidemiology, and End Results database, and separated into surgery and nonsurgery groups based on whether the primary tumor was resected. Propensity score matching (PSM) was applied to balance confounding factors between the two groups. A nomogram was developed using multivariable logistic regression to estimate surgical benefit. Our model is evaluated using multiple methods.

RESULTS

About 662 of 14,183 mPC patients had primary tumor surgery. Kaplan-Meier analyses showed that the surgery group had a better prognosis. After PSM, a survival benefit was still observed in the surgery group. Among the surgery cohort, 202 patients survived longer than 4 months (surgery-beneficial group). The nomogram discriminated better in training and validation sets under the receiver operating characteristic (ROC) curve (AUC), and calibration curves were consistent. Decision curve analysis (DCA) revealed that it was clinically valuable. This model is better at identifying candidates for primary tumor excision.

CONCLUSION

A helpful prediction model was developed and validated to identify ideal candidates who may benefit from primary tumor resection in mPC.

Fibroblast Activation Protein-Targeted PET/CT with 18F-Fibroblast Activation Protein Inhibitor-74 for Evaluation of Gastrointestinal Cancer: Comparison with 18F-FDG PET/CT

Fibroblast activation protein is overexpressed in the stroma of several cancer types. 18F-fibroblast activation protein inhibitor (FAPI)-74 is a PET tracer with high selectivity for fibroblast activation protein and has shown high accumulation in human tumors in clinical studies. However, the use of 18F-FAPI-74 for PET imaging of gastrointestinal cancer has not been systematically investigated. Herein, we investigated the diagnostic accuracy of 18F-FAPI-74 (18F-LNC1005) PET/CT in gastric, liver, and pancreatic cancers and compared the results with those of 18F-FDG PET/CT. Methods: This prospective study analyzed patients with confirmed gastric, liver, or pancreatic malignancies who underwent concurrent 18F-FDG and 18F-FAPI-74 PET/CT between June 2022 and December 2022. PET/CT findings were confirmed by histopathology or radiographic follow-up. 18F-FDG and 18F-FAPI-74 uptake and tumor-to-background ratios were compared using the Wilcoxon signed-rank test. The McNemar test was used to compare the diagnostic accuracy of the 2 scans. Results: Our cohort consisted of 112 patients: 49 with gastric cancer, 39 with liver cancer, and 24 with pancreatic cancer. Among them, 69 patients underwent PET/CT for initial staging and 43 for recurrence detection. Regarding lesion-based diagnostic accuracy, 18F-FAPI-74 PET/CT showed higher sensitivity than did 18F-FDG in the detection of primary tumors (gastric cancer, 88% [22/25] vs. 60% [15/25], P = 0.016; liver cancer, 100% [22/22] vs. 82% [18/22], P = 0.125; pancreatic cancer, 100% [22/22] vs. 86% [19/22], P = 0.250), local recurrence (92% [23/25] vs. 56% [14/25]; P = 0.021), involved lymph nodes (71% [41/58] vs. 40% [23/58]; P < 0.001), and bone and visceral metastases (98% [350/358] vs. 47% [168/358]; P < 0.001). Compared with 18F-FDG, 18F-FAPI-74 PET/CT upstaged 17 patients' TNM staging among all treatment-naïve patients (17/69, 25%) and changed the clinical management of 4 patients (4/43, 9%) in whom recurrence or metastases were detected. Conclusion: 18F-FAPI-74 PET/CT is superior to 18F-FDG PET/CT in detecting primary tumors, local recurrence, lymph node involvement, and bone and visceral metastases in gastric, pancreatic, and liver cancers, with higher uptake in most primary and metastatic lesions.

Serum aspartate aminotransferase is an adverse prognostic indicator for patients with resectable pancreatic ductal adenocarcinoma

OBJECTIVE

In this study, the association between preoperative levels of serum liver enzymes and overall survival (OS) was evaluated in patients with resectable pancreatic cancer.

METHODS

Preoperative serum levels of alanine aminotransferase (ALT), aspartate aminotransferases (AST), γ-glutamyltransferase, alkaline phosphatase, and lactate dehydrogenase of 101 patients with pancreatic ductal adenocarcinoma (PDAC) were collected. Univariate and multivariate Cox hazard models were used to identify independent variables associated with OS in this cohort.

RESULTS

Patients with elevated AST levels had significantly worse OS than patients with lower AST levels. A nomogram was created using TNM staging and AST levels and was shown to be more accurate in prediction than the American Joint Committee on Cancer 8th edition standard method.

CONCLUSION

Preoperative AST levels could be a novel independent prognostic biomarker for patients with PDAC. The incorporation of AST levels into a nomogram with TNM staging can be an accurate predictive model for OS in patients with resectable PDAC.

Myofibroblastic CAF Density, Not Activated Stroma Index, Indicates Prognosis after Neoadjuvant Therapy of Pancreatic Carcinoma

Neoadjuvant therapy (NT) for advanced PDAC is an emerging concept, affecting both stroma and tumor. The Activated Stroma Index (ASI; ratio of activated cancer-associated fibroblasts (CAF) to collagen deposition) is a prognostic marker in upfront resected pancreatic adenocarcinoma (PDAC). We assessed ASI and its prognostic relevance after NT. Tissue from resection specimens of n = 48 PDAC patients after neoadjuvant chemotherapy with FOLFIRINOX (FOL; n = 31), gemcitabine + nab-paclitaxel (GEM; 7) or combination treatment (COMB; 10) was compared with upfront resected matched controls (RES; 69). Activated CAFs were assessed by immunohistochemistry for α-SMA, and collagen was stained with aniline blue; the stained area was then determined by computational imaging analysis and ASI was calculated. In GEM, ASI was significantly higher and collagen deposition lower than in controls and FOL. The lowest quartile of ASI values had significantly longer overall survival (OS) in RES, whereas in FOL, the highest quartile had the best prognosis. After NT, OS was significantly improved in the α-SMA-high group; in RES, however, survival was independent of α-SMA. Reversed prognostic association of ASI thus points to the differing significance of stromal composition after FOL, while improved prognosis with high CAF abundance suggests a synergistic effect of myofibroblasts with chemotherapy. These divergences impede usability of ASI after NT.

Prediction of anti-CD25 and 5-FU treatments efficacy for pancreatic cancer using a mathematical model

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal disease with rising incidence and with 5-years overall survival of less than 8%. PDAC creates an immune-suppressive tumor microenvironment to escape immune-mediated eradication. Regulatory T (Treg) cells and myeloid-derived suppressor cells (MDSC) are critical components of the immune-suppressive tumor microenvironment. Shifting from tumor escape or tolerance to elimination is the major challenge in the treatment of PDAC.

RESULTS

In a mathematical model, we combine distinct treatment modalities for PDAC, including 5-FU chemotherapy and anti- CD25 immunotherapy to improve clinical outcome and therapeutic efficacy. To address and optimize 5-FU and anti- CD25 treatment (to suppress MDSCs and Tregs, respectively) schedule in-silico and simultaneously unravel the processes driving therapeutic responses, we designed an in vivo calibrated mathematical model of tumor-immune system (TIS) interactions. We designed a user-friendly graphical user interface (GUI) unit which is configurable for treatment timings to implement an in-silico clinical trial to test different timings of both 5-FU and anti- CD25 therapies. By optimizing combination regimens, we improved treatment efficacy. In-silico assessment of 5-FU and anti- CD25 combination therapy for PDAC significantly showed better treatment outcomes when compared to 5-FU and anti- CD25 therapies separately. Due to imprecise, missing, or incomplete experimental data, the kinetic parameters of the TIS model are uncertain that this can be captured by the fuzzy theorem. We have predicted the uncertainty band of cell/cytokines dynamics based on the parametric uncertainty, and we have shown the effect of the treatments on the displacement of the uncertainty band of the cells/cytokines. We performed global sensitivity analysis methods to identify the most influential kinetic parameters and simulate the effect of the perturbation on kinetic parameters on the dynamics of cells/cytokines.

CONCLUSION

Our findings outline a rational approach to therapy optimization with meaningful consequences for how we effectively design treatment schedules (timing) to maximize their success, and how we treat PDAC with combined 5-FU and anti- CD25 therapies. Our data revealed that a synergistic combinatorial regimen targeting the Tregs and MDSCs in both crisp and fuzzy settings of model parameters can lead to tumor eradication.

Open irreversible electroporation for isolated local recurrence of pancreatic ductal adenocarcinoma after primary surgery

BACKGROUND/OBJECTIVES

Irreversible electroporation (IRE) is an emerging treatment for locally advanced pancreatic cancer (LAPC) which in some cohorts has been associated with severe complications. Additionally, re-resection of isolated local recurrence (ILR) after pancreatic ductal adenocarcinoma (PDAC) can improve survival. We investigated safety, feasibility and oncologic outcomes in the first report on open IRE for unresectable ILR of PDAC in a staged surgical approach.

METHODS

Records of the prospectively documented institutional database were screened for patients undergoing laparotomy in IRE-standby due to questionable resectability. Endpoints were morbidity, mortality and overall (OS) and progression free survival (PFS). Data of LAPC and ILR were compared statistically for safety and feasibility analysis.

RESULTS

Intraoperative IRE was performed in 11 ILR and 14 LAPC. Six (54.5%) ILR and 10 (71.4%) LAPC patients had postoperative complications, type and frequency did not differ significantly. Major complications occurred in one ILR and two LAPC patients. Median OS was 20.0 months (95% CI: 2.7-37.3) after IRE for ILR and 28 (17.4-38.6) for LAPC. Median PFS after IRE was seven months for both ILR (4.1-9.9; n = 9) and LAPC (2.3-11.7; n = 13).

CONCLUSION

Open IRE for unresectable ILR was associated with acceptable perioperative risk. In this small, highly selected subset of patients with limited therapeutic options ancillary treatment with IRE might improve survival. Randomized treatment studies are required to establish the definitive role of IRE as compared to palliative standards of care in unresectable recurrence of PDAC and inconvertible LAPC.

Management problems in patients with pancreatic cancer from a surgeon's perspective

Pancreatic cancer is one of the most lethal gastrointestinal tumor entities. Surgery is the only chance for cure; however, only a minority of patients can be offered this option. Due to the anatomic location of the gland, tumor-related problems and complications affecting the surrounding structures are common, leading to biliary and gastric outlet obstruction as well as portal vein thrombosis. This review article summarizes the management of pancreatic cancer-related problems from a surgical point of view. We further describe surgical treatment options in unresectable, metastasized and recurring pancreatic cancer, highlighting potential resection of oligometastatic disease in selected settings.

Metastatic pancreatic adenocarcinomas could be classified into M1a and M1b category by the number of metastatic organs

Background

With the improvement of treatment and prognosis for patients with late malignant diseases, certain malignancies with distant metastasis (M1 category) have been further classified into M1a (single metastatic site) and M1b (multiple metastatic sites) category in the staging system. We aimed to assess the feasibility of sub-classifying metastatic pancreatic adenocarcinoma (mPA) into M1a and M1b category depending on the number of metastatic organs.

Methods

Patient records were collected from the Surveillance, Epidemiology, and End Results (SEER) database (2010–2015). Univariable and multivariable analyses were performed using the Cox regression model. Then survival analysis was determined using the Kaplan–Meier method.

Results

A total of 11,885 patients were included in this analysis, including 9425 patients with single metastasis and 2460 patients with multiple metastases. Multivariable analysis showed that gender, age, marital status, grade, surgery, chemotherapy, and radiotherapy were independent prognostic factors for patients with single metastasis; gender, age, marital status, grade, chemotherapy and radiotherapy were independent prognostic factors for patients with multiple metastases. Notably, surgery was an independent prognostic factor for patients with single metastasis (P < 0.001) but not for patients with multiple metastases (P = 0.134). Kaplan–Meier analysis showed that patients with single metastasis (M1a) had better survival outcomes than patients with multiple metastases (M1b) (P < 0.001).

Conclusions

PA patients with M1 diseases could be divided into M1a (single metastasis) category and M1b (multiple metastases) category by the number of metastatic organs. The subclassification would facilitate individualized treatment for late PA patients. Surgery was associated with lower mortality in M1a patients but not significantly in M1b patients.

Diffusion Kurtosis Imaging-A Superior Approach to Assess Tumor-Stroma Ratio in Pancreatic Ductal Adenocarcinoma

Extensive desmoplastic stroma is a hallmark of pancreatic ductal adenocarcinoma (PDAC) and contributes to tumor progression and to the relative resistance of tumor cells towards (radio) chemotherapy. Thus, therapies that target the stroma are under intense investigation. To allow the stratification of patients who would profit from such therapies, non-invasive methods assessing the stroma content in relation to tumor mass are required. In the current prospective study, we investigated the usefulness of diffusion-weighted magnetic resonance imaging (DW-MRI), a radiologic method that measures the random motion of water molecules in tissue, in the assessment of PDAC lesions, and more specifically in the desmoplastic tumor stroma. We made use of a sophisticated DW-MRI approach, the so-called diffusion kurtosis imaging (DKI), which possesses potential advantages over conventional and widely used monoexponential diffusion-weighted imaging analysis (cDWI). We found that the diffusion constant D from DKI is highly negatively correlated with the percentage of tumor stroma, the latter determined by histology. D performed significantly better than the widely used apparent diffusion coefficient (ADC) from cDWI in distinguishing stroma-rich (>50% stroma percentage) from stroma-poor tumors (≤50% stroma percentage). Moreover, we could prove the potential of the diffusion constant D as a clinically useful imaging parameter for the differentiation of PDAC-lesions from non-neoplastic pancreatic parenchyma. Therefore, the diffusion constant D from DKI could represent a valuable non-invasive imaging biomarker for assessment of stroma content in PDAC, which is applicable for the clinical diagnostic of PDAC.

Metabolic Profiling of Early and Late Recurrent Pancreatic Ductal Adenocarcinoma Using Patient-Derived Organoid Cultures

Pancreatic ductal adenocarcinoma (PDAC) is associated with high mortality and will become the second most common cause of cancer-associated mortality by 2030. The poor prognosis arises from a lack of sensitive biomarkers, limited therapeutic options, and the astonishingly high recurrence rate after surgery of 60-80%. The factors driving this recurrence, however, remain enigmatic. Therefore, we generated patient-derived organoids (PDOs) from early- and late-recurrent PDAC patients. Cellular identity of PDOs was confirmed by qPCR, ddPCR, and IHC analyses. This is the first study investigating the metabolism in PDOs of different, clinically significant PDAC entities by untargeted GC/MS profiling. Partial least square discriminant analysis unveiled global alterations between the two sample groups. We identified nine metabolites to be increased in early recurrent PDOs in comparison to late recurrent PDOs. More than four-times increased were fumarate, malate, glutamate, aspartate, and glutamine. Hence, α-keto acids were elevated in PDO-conditioned medium derived from early recurrent patients. We therefore speculate that an increased anaplerotic metabolism fuels the Krebs-cycle and a corresponding higher accessibility to energy fastens the recurrence in PDAC patients. Therein, a therapeutic intervention could delay PDAC recurrence and prolong survival of affected patients or could serve as biomarker to predict recurrence in the future.

Benefits of Conversion Surgery after Multimodal Treatment for Unresectable Pancreatic Ductal Adenocarcinoma

BACKGROUND

Traditionally, the treatment options for unresectable locally advanced (UR-LA) and metastatic (UR-M) pancreatic ductal adenocarcinoma (PDAC) are palliative chemotherapy or chemoradiotherapy. The benefits of surgery for such patients remains unknown. The present study investigated clinical outcomes of patients undergoing conversion surgery (CS) after chemo(radiation)therapy for initially UR-PDAC.

METHODS

We recruited patients with UR-PDAC who underwent chemo(radiation)therapy for initially UR-PDAC between April 2006 and September 2017. We analyzed resectability of CS, predictive parameters for overall survival, and early recurrence (within six months).

RESULTS

A total of 468 patients (108 with UR-LA and 360 with UR-M PDAC) were enrolled in this study, of whom, 17 (15.7%) with UR-LA and 15 (4.2%) with UR-M underwent CS. The median survival time (MST) and five-year survival of patients who underwent CS was 37.2 months and 34%, respectively; significantly better than non-resected patients (nine months and 1%, respectively, p < 0.0001). MST did not differ according to UR-LA or UR-M (50.5 vs. 29.0 months, respectively, p = 0.53). Early recurrence after CS occurred in eight patients (18.8%). Lymph node metastasis, positive washing cytology, large tumor size (>35 mm), and lack of postoperative adjuvant chemotherapy were statistically significant predictive factors for early recurrence. Moreover, the site of pancreatic lesion and administration of postoperative adjuvant chemotherapy were statistically significant prognostic factors for overall survival in the patients undergoing CS.

CONCLUSION

Conversion surgery offers benefits in terms of increase survival for initially UR-PDAC for patients who responded favorably to chemo(radiation)therapy when combined with postoperative adjuvant chemotherapy.

The effect of ibrutinib on radiosensitivity in pancreatic cancer cells by targeting EGFR/AKT/mTOR signaling pathway

Radiotherapy is an effective treatment for pancreatic cancer. However, radio-resistance often resulted in poor prognostic. Ibrutinib is an orally small molecule drug in B cell malignancies. Here, we investigated for the first time the effect of ibrutinib on radio-sensitivity of human pancreatic cancer cells in vitro and the potential mechanism involved in it. Human BXPC3 and Capan2 cell lines were treated with ibrutinib, and cell viability was conducted with CCK-8 assay. Cell clone formation was observed after treated with ibrutinib and (or) radiation by clone formation assay. The cell cycle and cell apoptosis were measured by flow cytometry. Protein levels was analyzed by western blot. The results revealed that ibrutinib inhibited the proliferation of pancreatic cancer cells. Ibrutinib enhanced the effect of radiation with a sensitization enhancement ratio (SER) of 1.34, 1.68 in BXPC3 and Capan2 cells respectively. Ibrutinib combined with radiation induced G2/M arrest and cell apoptosis. Further investigations revealed that ibrutinib decreased the phosphorylation of EGFR, then reversed the upregulation of p-AKT and downstream genes by radiation. In conclusion, these results suggested that ibrutinib might be an excellent radiosensitizer in pancreatic cancer.

Pancreatoduodenectomy En Bloc With Vascular Resections in Borderline Resectable Pancreatic Cancer

BACKGROUND/AIM

Pancreatic cancer remains asymptomatic for a long period of time, being frequently diagnosed when vascular invasion is already present. Such cases are widely known as borderline lesions. The aim of this study was to identify the effectiveness of vascular resection in this subgroup of patients.

PATIENTS AND METHODS

Fifteen such cases were submitted to surgery with curative intent.

RESULTS

Eight cases were diagnosed with borderline resectable lesions with portal vein invasion and were submitted to per primam resection and seven cases were initially diagnosed with arterial invasion and had been initially submitted to neoadjuvant chemotherapy followed by resection. In all cases portal vein resection was needed while in other four cases association of superior mesenteric artery resection was performed. Postoperatively, five patients developed complications requiring reoperation, three of whom died at the end of the first postoperative month. The histopathological studies confirmed the completeness of resection in all cases.

CONCLUSION

Vascular resections in pancreatic cancer resections remain demanding procedures, and are reserved for cases in which a radical resection is feasible.

Conversion Surgery for Pancreatic Cancer-The Impact of Neoadjuvant Treatment

Pancreatic ductal adenocarcinoma (PDAC) has still a dismal prognosis, mainly because only 15–20% of all patients present with resectable tumor stages at the time of diagnosis. Due to locally extended tumor growth or distant metastases upfront resection is not reasonable in the majority of patients. Considerably, PDAC will be the 2nd most frequent cause of cancer-related deaths within the next 10 years for both men and women. While there is currently no convincing evidence for the use of neoadjuvant therapy in resectable PDAC, there are controversial results from studies investigating neoadjuvant treatment concepts in borderline resectable PDAC (BR-PDAC). However, the definition of BR-PDAC is a topic of debate. While BR-PDAC has originally been defined on merely anatomical criteria, the International Association of Pancreatology (IAP) has recently suggested a broader definition based on a combination of anatomical (A) findings, biological (B) criteria (which reflect tumor aggressiveness), and conditional (C) aspects (which respect host-related condition). In case of BR-PDAC with venous invasion alone, upfront resection is generally recommended whenever technically possible in patients fit for surgery and without evidence for lymph node metastases. In contrast, in case of arterial invasion neoadjuvant therapy is regarded as the treatment of choice. The same accounts for high CA 19-9 levels, suspected or proven lymph node involvement and poor performance status. In locally advanced PDAC (LA-PDAC), neoadjuvant treatment represents the standard of care resulting in proportionally high rates of secondary resection. This “conversion” surgery offers the chance for improved survival times in an otherwise palliative situation. Herein, we summarize the current evidence of different treatment strategies for pancreatic cancer with a focus on conversion surgery and the impact of neoadjuvant treatment in this setting.

TRIM59 predicts poor prognosis and promotes pancreatic cancer progression via the PI3K/AKT/mTOR-glycolysis signaling axis

Aberrant expression of the tripartite motif containing 59 (TRIM59) has been reported to participate in the development and progression of various human cancers. However, its expression pattern and cellular roles in pancreatic cancer (PC) remains unclear. In our study, we found that TRIM59 expression was significantly increased in PC tissues and was positively correlated with several malignant behaviors and poor overall survival of PC patients based on bioinformatics analysis and immunohistochemistry staining. Functionally, small interfering RNA-mediated TRIM59 depletion inhibited cell proliferation and migration in vitro, while TRIM59 overexpression promoted cell proliferation and migration in vitro and drove tumor growth and liver metastasis in vivo. Mechanically, TRIM59 was found to enhance glycolysis through activating the PI3K/AKT/mTOR pathway, ultimately contributing to PC progression. Taken together, our results demonstrate that TRIM59 may be a potential predictor for PC and promotes PC progression via the PI3K/AKT/mTOR-glycolysis signaling pathway, which establishes the rationale for targeting the TRIM59-related pathways to treat PC.

Do Patients Diagnosed with Metastatic Pancreatic Cancer Benefit from Primary Tumor Surgery? A Propensity-Adjusted, Population-Based Surveillance, Epidemiology and End Results (SEER) Analysis

Background

With the progress in surgical techniques and management of complications, pancreatic resection can be safely performed in experienced hospitals. Pancreatic resection enables surgeons to assess the effect of surgery for metastatic cases, even when there is limited information. In the present study we evaluated the role of primary tumor resection for metastatic pancreatic cancer (mPC) by using the Surveillance, Epidemiology and End Results (SEER) database.

Material/Methods

Metastatic pancreatic cancer patients treated at our hospital from 2004 to 2015 were identified. The effect of surgery on cancer-specific survival was assessed by restricted mean survival time (RMST) and stabilized inverse probability of treatment weight-adjusted analysis after propensity score matching (PSM).

Results

A total of 2694 mPC patients were included. Of this population, 365 adults underwent primary tumor resection. After propensity matching, postsurgical patients had longer RMST than non-surgery patients (1: 1 PSM 11.60 months vs. 8.98 months; 1: 2 PSM 11.61 months vs. 9.10 months; p<0.01). Stabilized inverse probability of treatment weight-adjusted analysis yielded similar results (p<0.01).

Conclusions

Our study supports the hypothesis that patients with mPC can benefit from primary tumor surgery. However, the surgical inclusion criteria and the appropriate role of surgery, such as its effect on symptom control, quality of life, and the extent to which it prolongs survival for metastatic pancreatic cancer, remain to be completely assessed by well-designed, prospective, randomized clinical trials.

Protocol of a prospective, monocentric phase I/II feasibility study investigating the safety of multimodality treatment with a combination of intraoperative chemotherapy and surgical resection in locally confined or borderline resectable pancreatic cancer: the combiCaRe study

INTRODUCTION

Pancreatic cancer is a devastating disease with an exceptionally poor prognosis. Complete resection of the primary tumour followed by adjuvant chemotherapy is the current standard treatment for patients with resectable disease and the only curative treatment option. However, long-term survival remains rare. Tumour cell dissemination due to manipulation during surgery may increase the rate of future metastases and local recurrence, and perioperative chemotherapy might diminish local, distant and circulating minimal residual disease. Yet, safety and feasibility of systemic chemotherapeutic treatments during pancreatic cancer resection have to be evaluated in a first instance.

METHODS AND ANALYSIS

This is a prospective, single-centre phase I/II feasibility study to investigate the safety and tolerability of a combination of intraoperative chemotherapy and surgical resection in pancreatic cancer. Forty patients with locally confined or borderline resectable pancreatic cancer, meeting all proposed criteria will be included. Participants will receive 400 mg/m2 calcium folinate over 2 hours and 2000 mg/m2 5-fluorouracil over 48 hours, started on the day before pancreatic surgery and thus continuing during surgery. Participants will be followed until 60 days after surgery. The primary endpoint is the 30-day overall complication rate according to the Clavien-Dindo classification. Secondary endpoints comprise toxicity and treatment associated complications. Patients receiving perioperative chemotherapy will be compared with a propensity score matched contemporary control group of 70 patients with pancreatic cancer receiving the standard treatment. This trial also contains an ancillary translational study to analyse disseminated tumour cells and effects of pharmacological interventions in pancreatic cancer.

ETHICS AND DISSEMINATION

CombiCaRe has been approved by the German Federal Institute for Drugs and Medical Devices (reference number 4042787) and the Medical Ethics Committee of Heidelberg University (reference number AFmo-269/2018). The results of this trial will be presented at national and international conferences and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

German Clinical Trials Register (DRKS00015766).

CT response of primary tumor and CA19-9 predict resectability of metastasized pancreatic cancer after FOLFIRINOX

BACKGROUND

Effective chemotherapy protocols are currently changing the treatment options for metastasized pancreatic cancer. Survival benefits after synchronous metastasectomy have been reported for selected patients. We set out to assess predictive factors of resectability for synchronous metastases after FOLFIRINOX.

METHODS

Consecutive patients with metastatic pancreatic cancer undergoing surgery after FOLFIRINOX between 2011 and 2017 were identified from a prospectively collected database. Surgery following chemotherapy was indicated in patients with no more than six metastatic lesions, no progression detected on CT, and technically resectable disease. Patients who received synchronous metastasectomy were compared with patients who received explorative laparotomy or palliative surgery in terms of predictors of resectability and overall survival. In patients undergoing resection, prognostic factors were examined.

RESULTS

Of 101 patients scheduled for surgery after FOLFIRINOX, synchronous metastasectomy was performed in 43 cases (43%) and non-resection surgery in 58 cases (57%). The shrinkage rate of the primary tumor on CT (P = 0.04) and the postchemotherapy serum CA19-9 concentration (P = 0.02) were associated with resectability. The median overall survival of the patients undergoing metastasectomy was longer than that of the patients without resection (21.9 months vs 16.4 months, P = 0.006). Postchemotherapy serum CA19-9 value (P = 0.04) and lymph node ratio (P = 0.01) were prognostic factors in the patients undergoing metastasectomy.

CONCLUSIONS

In selected patients who satisfied our surgical criteria, shrinkage rate of primary tumor and postchemotherapy serum CA19-9 level, which predict resectability of metastasized pancreatic cancer, should be considered in decision making to avoid unnecessary surgery.

Surgery for Pancreatic Cancer after neoadjuvant treatment

Pancreatic ductal adenocarcinoma (PDAC) remains to be a therapeutic challenge as only 15%-20% of all patients present with resectable tumor stages by the time of diagnosis. In the remaining patients, either local tumor extension or systemic spread are obstacles for a surgical therapy as the only chance for long-term survival. With regard to local tumor extension, PDAC has been classified as resectable, borderline-resectable (BR) or locally advanced (LA). While there is currently no evidence for neoadjuvant therapy in resectable PDAC, this issue remains controversial in BR-PDAC. In the case of venous tumor involvement, guidelines mostly recommend upfront resection, when technically possible; whereas arterial involvement is regarded as an indication for chemotherapy or chemoradiotherapy first. Furthermore, in locally advanced PDAC, neoadjuvant treatment approaches have recently resulted in high rates of secondary resection, thus allowing "conversion" surgery in an otherwise palliative treatment situation. The present review gives an overview on the current literature of treatment concepts in these situations and additionally focuses of evaluation of resectability after neoadjuvant therapy as well as technical aspects in this specific situation.

Gemcitabine in Combination with a Second Cytotoxic Agent in the First-Line Treatment of Locally Advanced or Metastatic Pancreatic Cancer: a Systematic Review and Meta-Analysis

BACKGROUND

It remains controversial whether the addition of a second cytotoxic agent can further improve the therapeutic effect of gemcitabine monotherapy in advanced or metastatic pancreatic cancer (LA/MPC).

OBJECTIVE

The objective of the present systematic review and meta-analysis was to investigate the efficacy and safety of gemcitabine-based doublet chemotherapy regimens compared to single-agent gemcitabine in the first-line treatment of unresectable LA/MPC.

METHODS

We searched for randomized controlled trials (RCTs) of gemcitabine monotherapy versus gemcitabine in combination with a second cytotoxic agent in patients with LA/MPC. The last search date was December 31, 2016.

RESULTS

Twenty-seven RCTs were identified and included in the present systematic review and meta-analysis, involving a total of 7343 patients. The meta-analysis showed that gemcitabine-based combination therapy significantly improved overall survival (OS) (HR: 0.89; 95% confidence interval (CI): 0.85-0.94; P < 0.0001), progression-free survival (PFS) (HR: 0.80; 95% CI: 0.73-0.88; P < 0.0001), and overall response rate (ORR) (RR: 1.83; 95% CI: 1.62-2.07; P < 0.0001) in comparison to single-agent gemcitabine. Subgroup analysis suggested that the antitumor activity differed between gemcitabine-based combination regimens: doublet regimens of gemcitabine plus a taxoid, and gemcitabine plus a fluoropyrimidine, in particular an oral fluoropyrimidine, resulted in a significant OS benefit for the patients. However, the combination of gemcitabine with other cytotoxic agents, such as platinum compounds or topoisomerase inhibitors failed to reduce the mortality risk. Combination therapy caused more grade 3/4 toxicities, including neutropenia, thrombocytopenia, vomiting, diarrhea, and fatigue.

CONCLUSIONS

Gemcitabine-based doublet regimens demonstrated superiority over gemcitabine monotherapy in overall efficacy, but were associated with increased toxicity. Different gemcitabine-based combinations showed different antitumor activity, and doublet regimens of gemcitabine in combination with a taxoid or a fluoropyrimidine, in particular an oral fluoropyrimidine provided significant survival benefits in the first-line treatment of unresectable LA/MPC.

The high stromal SPARC expression is independently associated with poor survival of patients with resected pancreatic ductal adenocarcinoma treated with adjuvant gemcitabine in combination with S-1 or adjuvant gemcitabine alone

BACKGROUND

Although postoperative adjuvant chemotherapy for pancreatic ductal adenocarcinoma (PDAC) improves survival, its efficacy varies among individuals. Identification of biomarkers that can predict the efficacy of adjuvant chemotherapy for PDAC is essential.

OBJECTIVES

To investigate the predictive value of secreted protein acidic and rich in cysteine (SPARC) expression in patients with PDAC treated with adjuvant gemcitabine in combination with S-1 (adjuvant GS) or adjuvant gemcitabine alone (adjuvant G alone).

METHODS

Stromal SPARC and cytoplasmic SPARC were examined immunohistochemically in 211 PDAC patients treated with adjuvant GS or G alone after resection. The association of SPARC expression with clinicopathological factors, disease-free survival (DFS) and overall survival (OS) were analyzed.

RESULTS

In multivariate analysis, borderline resectable with arterial contact (BR-A) (P = .002), higher preoperative CA 19-9 level (≥91 U/ml) (P = .005), moderately or poorly (P = .003), presence of lymph node metastasis (P = .012) and high stromal SPARC expression (P = .013) were independent predictors of poor DFS. Moreover, BR-A (P = .003), higher preoperative CA 19-9 level (≥91 U/ml) (P = .007) and high stromal SPARC expression (P < .001) were identified as independent predictors of poor OS. In contrast, cytoplasmic SPARC expression did not affect DFS and OS.

CONCLUSIONS

High stromal SPARC expression was an independent predictor of poor DFS and OS in patients treated with adjuvant GS or G alone. Stromal SPARC expression could be a relevant biomarker for prediction of prognosis in PDAC patients after resection treated with adjuvant GS or G alone.

FAK and paxillin, two potential targets in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is a devastating cancer in large part due to late diagnosis and a lack of effective screening tests. In spite of recent progress in imaging, surgery and new therapeutic options for pancreatic cancer, the overall five-year survival still remains unacceptably low. Numerous studies have shown that focal adhesion kinase (FAK) is activated in many cancers including PDAC and promotes cancer progression and metastasis. Paxillin, an intracellular adaptor protein that plays a key role in cytoskeletal organization, connects integrins to FAK and plays a key role in assembly and disassembly of focal adhesions. Here, we have reviewed evidence in support of FAK as a potential therapeutic target and summarized related combinatorial therapies.

Recent advances in genetic modification of adenovirus vectors for cancer treatment

Adenoviruses are widely used to deliver genes to a variety of cell types and have been used in a number of clinical trials for gene therapy and oncolytic virotherapy. However, several concerns must be addressed for the clinical use of adenovirus vectors. Selective delivery of a therapeutic gene by adenovirus vectors to target cancer is precluded by the widespread distribution of the primary cellular receptors. The systemic administration of adenoviruses results in hepatic tropism independent of the primary receptors. Adenoviruses induce strong innate and acquired immunity in vivo. Furthermore, several modifications to these vectors are necessary to enhance their oncolytic activity and ensure patient safety. As such, the adenovirus genome has been engineered to overcome these problems. The first part of the present review outlines recent progress in the genetic modification of adenovirus vectors for cancer treatment. In addition, several groups have recently developed cancer-targeting adenovirus vectors by using libraries that display random peptides on a fiber knob. Pancreatic cancer-targeting sequences have been isolated, and these oncolytic vectors have been shown by our group to be associated with a higher gene transduction efficiency and more potent oncolytic activity in cell lines, murine models, and surgical specimens of pancreatic cancer. In the second part of this review, we explain that combining cancer-targeting strategies can be a promising approach to increase the clinical usefulness of oncolytic adenovirus vectors.

Role of Notch signaling pathway in pancreatic cancer

Pancreatic cancer (PC) is one of the highly aggressive malignancies in the United States. It has been shown that multiple signaling pathways are involved in the pathogenesis of PC, such as JNK, PI3K/AKT, Rho GTPase, Hedgehog (Hh) and Skp2. In recent years, accumulated evidence has demonstrated that Notch signaling pathway plays critical roles in the development and progression of PC. Therefore, in this review we discuss the recent literature regarding the function and regulation of Notch in the pathogenesis of PC. Moreover, we describe that Notch signaling pathway could be down-regulated by its inhibitors or natural compounds, which could be a novel approach for the treatment of PC patients.

Association of genetic polymorphisms with survival of pancreatic ductal adenocarcinoma patients

Germline genetic variability might contribute, at least partially, to the survival of pancreatic ductal adenocarcinoma (PDAC) patients. Two recently performed genome-wide association studies (GWAS) on PDAC overall survival (OS) suggested (P < 10(-5)) the association between 30 genomic regions and PDAC OS. With the aim to highlight the true associations within these regions, we analyzed 44 single-nucleotide polymorphisms (SNPs) in the 30 candidate regions in 1722 PDAC patients within the PANcreatic Disease ReseArch (PANDoRA) consortium. We observed statistically significant associations for five of the selected regions. One association in the CTNNA2 gene on chromosome 2p12 [rs1567532, hazard ratio (HR) = 1.75, 95% confidence interval (CI) 1.19-2.58, P = 0.005 for homozygotes for the minor allele] and one in the last intron of the RUNX2 gene on chromosome 6p21 (rs12209785, HR = 0.88, 95% CI 0.80-0.98, P = 0.014 for heterozygotes) are of particular relevance. These loci do not coincide with those that showed the strongest associations in the previous GWAS. In silico analysis strongly suggested a possible mechanistic link between these two SNPs and pancreatic cancer survival. Functional studies are warranted to confirm the link between these genes (or other genes mapping in those regions) and PDAC prognosis in order to understand whether these variants may have the potential to impact treatment decisions and design of clinical trials.

Pancreatic Cancer: Pathogenesis and Diagnosis

Pancreatic cancer is a fatal malignancies which is predominantly seen in men and at advanced age (40-85 years) and has an aggressive course. Its frequency is gradually increasing over the past years. It accounts for 2% of all cancers and 5% of cancer-related deaths. Pancreatic cancer takes the first place among asymptomatic cancers. Ninety percent of cases are adenocarcinomas. Ten percent of the patients have a familial disposition. The disease is very difficult to detect as it has no early signs and spreads rapidly to surrounding organs is one of the most deadly types of cancer. Pancreatic cancer may result from hereditary germline or somatic acquired mutations in cancer-related genes and mutations also cause cancer progression and metastasis.

Autologous Islet Transplantation in Patients Requiring Pancreatectomy: A Broader Spectrum of Indications Beyond Chronic Pancreatitis

Islet autotransplantation (IAT) is usually performed in patients undergoing pancreatic surgery for chronic pancreatitis. In the present series, IAT was offered also to patients undergoing pancreatic surgery for both nonmalignant and malignant diseases, having either completion pancreatectomy as treatment for severe pancreatic fistulas (n = 21) or extensive distal pancreatectomy for neoplasms of the pancreatic neck (n = 19) or pancreatoduodenectomy because of the high risk of pancreatic fistula (n = 32). Fifty-eight of 72 patients who were eligible to this broader spectrum of indication actually received IAT. There was no evidence of a higher-than-expected rate of major complications for pancreatectomy. Forty-five patients receiving IAT were still alive at the time of the last scheduled follow-up (1375 ± 365 days). Eighteen (95%) of 19 and 11 (28%) of 39 patients reached insulin independence after partial or total pancreatectomy, respectively. The metabolic results were dependent on the transplanted islet mass. Thirty-one of 58 patients had malignant diseases of the pancreas or periampullary region, and only three patients developed ex novo liver metastases after IAT (median follow-up 914 ± 382 days). Our data demonstrate the feasibility, efficacy, and safety of IAT for a broader spectrum of clinical indications beyond chronic pancreatitis.

Innovations in macroscopic evaluation of pancreatic specimens and radiologic correlation

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The axial slicing technique offers many advantages in accurate estimation of tumors extend and staging.

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Cross-sectional axial imaging is the best technique for accurate radiologic-pathologic correlation.

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Correlation may explain any discrepancies between radiological and histopathological findings.

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Pathology correlation may offer a better understanding of the missed findings by imaging or pitfalls

The purpose of this study was to evaluate the feasibility of a novel dissection technique of surgical specimens in different cases of pancreatic tumors and provide a radiologic pathologic correlation. In our hospital, that is a referral center for pancreatic diseases, the macroscopic evaluation of the pancreatectomy specimens is performed by the pathologists using the axial slicing technique (instead of the traditional procedure with longitudinal opening of the main pancreatic and/or common bile duct and slicing along the plane defined by both ducts). The specimen is sliced in an axial plane that is perpendicular to the longitudinal axis of the descending duodenum. The procedure results in a large number of thin slices (3–4 mm). This plane is identical to that of CT or MRI and correlation between pathology and imaging is straightforward. We studied 70 cases of suspected different solid and cystic pancreatic tumors and we correlated the tumor size and location, the structure—consistency (areas of necrosis—hemorrhage—fibrosis—inflammation), the degree of vessels’ infiltration, the size of pancreatic and common bile duct and the distance from resection margins. Missed findings by imaging or pitfalls were recorded and we tried to explain all discrepancies between radiology evaluation and the histopathological findings. Radiologic-pathologic correlation is extremely important, adding crucial information on imaging limitations and enabling quality assessment of surgical specimens. The deep knowledge of different pancreatic tumors’ consistency and way of extension helps to improve radiologists’ diagnostic accuracy and minimize the radiological-surgical mismatching, preventing patients from unnecessary surgery.

Borderline resectable pancreatic cancer

Surgery followed by adjuvant chemotherapy remains the only treatment option for pancreatic ductal adenocarcinoma (PDAC) with the chance of long-term survival. If a radical tumor resection is possible, 5-year survival rates of 20-25% can be achieved. Pancreatic surgery has significantly changed during the past years and resection approaches have been extended beyond standard procedures, including vascular and multivisceral resections. Consequently, borderline resectable pancreatic ductal adenocarcinoma (BR-PDAC), which has recently been defined by the International Study Group for Pancreatic Surgery (ISGPS), has become a controversial issue with regard to its management in terms of upfront resection vs. neoadjuvant treatment and sequential resection. Preoperative diagnostic accuracy to define resectability of PDAC is a keypoint in this context as well as the surgical and interdisciplinary expertise to perform advanced pancreatic surgery and manage complications. The present mini-review summarizes the current state of definition, management and outcome of BR-PDAC. Furthermore, the topic of ongoing and future studies on neoadjuvant treatment which is closely related to borderline resectability in PDAC is discussed.

Suppression of the Epidermal Growth Factor-like Domain 7 and Inhibition of Migration and Epithelial-Mesenchymal Transition in Human Pancreatic Cancer PANC-1 Cells

BACKGROUND

Epidermal growth factor-like domain multiple 7 (EGFL7), a secreted protein specifically expressed by endothelial cells during embryogenesis, recently was identified as a critical gene in tumor metastasis. Epithelial-mesenchymal transition (EMT) was found to be closely related with tumor progression. Accordingly, it is important to investigate the migration and EMT change after knock-down of EGFL7 gene expression in human pancreatic cancer cells.

MATERIALS AND METHODS

EGFL7 expression was firstly testified in 4 pancreatic cancer cell lines by real-time polymerase chain reaction (Real-time PCR) and western blot, and the highest expression of EGFL7 was found in PANC-1 cell line. Then, PANC-1 cells transfected with small interference RNA (siRNA) of EGFL7 using plasmid vector were named si-PANC-1, while transfected with negative control plasmid vector were called NC-PANC-1. Transwell assay was used to analyze the migration of PANC-1 cells. Real-time PCR and western blotting were used to detect the expression change of EGFL7 gene, EMT markers like E-Cadherin, N-Cadherin, Vimentin, Fibronectin and transcription factors like snail, slug in PANC-1, NC- PANC-1, and si-PANC-1 cells, respectively.

RESULTS

After successful plasmid transfection, EGFL7 gene were dramatically knock-down by RNA interference in si-PANC-1 group. Meanwhile, migration ability decreased significantly, compared with PANC-1 and NC-PANC-1 group. Meanwhile, the expression of epithelial phenotype marker E-Cadherin increased and that of mesenchymal phenotype markers N-Cadherin, Vimentin, Fibronectin dramatically decreased in si-PANC-1 group, indicating a reversion of EMT. Also, transcription factors snail and slug decreased significantly after RNA interference.

CONCLUSIONS

Current study suggested that highly-expressed EGFL7 promotes migration of PANC-1 cells and acts through transcription factors snail and slug to induce EMT, and further study is needed to confirm this issue.

Epidermal growth factor-like domain 7 promotes cell invasion and angiogenesis in pancreatic carcinoma

Epidermal growth factor-like domain 7 (EGFL7), also known as vascular endothelial stain, was firstly identified as a modulator of smooth muscle cell migration. Though the expression of EGFL7 was reported to be up-regulated during tumorigenesis, the clinical and biological functions of EGFL7 in pancreatic carcinoma (PC) were still not fully elucidated. In this study, we found that the serum EGFL7 level in PC tissues was statistically higher than that in normal subjects (p<0.001), and its level in non-resectable patients was also higher than that in resectable ones (p=0.013). Among these resectable PC patients, the postoperative EGFL7 expression was significantly down-regulated when tumors were resected (p=0.018). Using the immunohistochemistry method, our results demonstrated that the positive expression of EGFL7 was significantly associated with the TNM stage (p=0.024), lymph node metastasis (p=0.003) and local invasion (p=0.022), and the EGFL7 expression closely correlated to the micro-vessel density (MVD) in PC tissues by Spearman analysis (r=0.941, p=0.000). In vitro, EGFL7 was silenced by the small interference RNA in PC cells, and our data indicated that down-regulation of EGFL7 did not influence the cycle progression, proliferation, colony formation and apoptosis of PC cells (p>0.05), whereas inhibition of EGFL7 expression could decrease PaCa-2 cell invasion (p<0.05). More interestingly, by tubular formation, Chick embryo chorioallantoic membrane (CAM) and ELISA assays, our results revealed that silencing EGFL7 expression represented a strong inhibiting effect on tubular formation of micro-vessels through down-regulating the protein levels of VEGF and Ang-2 (p<0.05). Our results raised the possibility of using EGFL7as a potential prognostic biomarker and therapy target of PC, and down-regulation of EGFL7 might be considered to be a potentially important molecular treatment strategy for patients with PC.

Vascular Resection in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignant tumors and represents the fifth most common cause of cancer-related deaths. It is associated with a poor prognosis, likely due to the tendency of the tumor for early local and distant spread. One of the major obstacles of effectively treating PDAC is the often late diagnosis. Among all options currently available for PDAC, surgical resection offers the only potential cure with 5-year survival rate of approximately 15-20 %. However, in the absence of metastatic disease, which precludes resection, assessment of vascular invasion is an important parameter for determining resectability for pancreatic cancer. The vascular involvement in patients with pancreatic carcinoma ranges between 21 and 64 %. Historically, vascular involvement has been considered a contraindication to resective cure. Meanwhile, the surgical approach of pancreatoduodenectomy (PD) combined with vascular resection and reconstruction has been widely applied in clinical practice to remove the tumor completely. Therefore, vascular invasion is no longer a surgical contraindication and the rate of surgical resection has greatly increased. Moreover, PD combined with vascular resection can account for 20 to 25 % of the total cases of PD surgery in a number of the larger pancreas treatment centers. The aim of this review is to provide an overview of management and outcome of vascular resection in PDAC surgery.

Surgery for oligometastasis of pancreatic cancer

The incidence of pancreatic adenocarcinoma (PDAC) has steadily increased over the past several decades. The majority of PDAC patients will present with distant metastases, limiting surgical management in this population. Hepatectomy and pulmonary metastasectomy (PM) has been well established for colorectal cancer patients with isolated, resectable hepatic or pulmonary metastatic disease. Recent advancements in effective systemic therapy for PDAC have led to the selection of certain patients where metastectomy may be potentially indicated. However, the indication for resection of oligometastases in PDAC is not well defined. This review will discuss the current literature on the surgical management of metastatic disease for PDAC with a specific focus on surgical resection for isolated hepatic and pulmonary metastases.

Research gaps in pancreatic cancer research and comparative effectiveness research methodologies

Despite advances in cancer care, pancreatic adenocarcinoma remains one of the most lethal tumors. Most patients with pancreatic cancer are diagnosed with late stage disease, and approximately 6 % of patients are alive 5 years after diagnosis. Of the 10-20 % of patients who are candidates for resection and multi-modality therapy, most will succumb to the disease with 5-year survival rates only reaching approximately 25 % (Lim et al. in Annals of surgery 237(1):74-85, 2003 [1]; Trede et al. in Annals of surgery 211(4):447-458, 1990 [2]; Crist et al. in Annals of surgery 206(3):358-365, 1987 [3]). Clearly, there is a need to improve the management of this disease. To identify gaps in research and formulate strategies to address these issues, we designed a framework to encompass the scope of research for pancreatic cancer. In this chapter, we will examine each topic heading within this framework for gaps in knowledge and present research strategies focusing on diverse comparative effectiveness research (CER) methodologies to address the identified gaps.

Diabetes after pancreatic surgery: novel issues

In the developed world, pancreatic surgery is becoming more common, with an increasing number of patients developing diabetes because of either partial or total pancreatectomy, with a significant impact on quality of life and survival. Although these patients are expected to consume increasing health care resources in the near future, many aspects of diabetes after pancreatectomy are still not well defined. The treatment of diabetes in these patients takes advantage of the therapies used in type 1 and 2 diabetes; however, no specific guidelines for its management, both immediately after pancreatic surgery or in the long term, have been developed. In this article, on the basis of both the literature and our clinical experience, we address the open issues and discuss the most appropriate therapeutic options for patients with diabetes after pancreatectomy.

How early can pancreatic cancer be recognized? A case report and review of the literature

The early symptoms of pancreatic cancer are often very vague. They may precede the diagnosis by years and go unrecognized. This makes pancreatic cancer one of the cancers with the worst survival rates. The progression rate of the early phase might be slower than previously thought. Here, we report a case where symptoms, including thromboembolism and new-onset diabetes mellitus, preceded the diagnosis of pancreatic cancer by 6 years or longer. The awareness of the early symptoms of pancreatic cancer is required for being vigilant and further diagnostic tests. A simple clinical model utilizing certain risk factors and symptoms for pancreatic cancer will help stratify the patients for further screening tests.

Circulating tumor cells in pancreatic cancer patients: Enrichment and cultivation

AIM: To investigate the feasibility of separation and cultivation of circulating tumor cells (CTCs) in pancreatic cancer (PaC) using a filtration device.

METHODS: In total, 24 PaC patients who were candidates for surgical treatment were enrolled into the study. Peripheral blood samples were collected before an indicated surgery. For each patient, approximately 8 mL of venous blood was drawn from the antecubital veins. A new size-based separation MetaCell^® technology was used for enrichment and cultivation of CTCs in vitro. (Separated CTCs were cultured on a membrane in FBS enriched RPMI media and observed by inverted microscope. The cultured cells were analyzed by means of histochemistry and immunohistochemistry using the specific antibodies to identify the cell origin.

RESULTS: CTCs were detected in 16 patients (66.7%) of the 24 evaluable patients. The CTC positivity did not reflect the disease stage, tumor size, or lymph node involvement. The same percentage of CTC positivity was observed in the metastatic and non-metastatic patients (66.7% vs 66.7%). We report a successful isolation of CTCs in PaC patients capturing proliferating cells. The cells were captured by a capillary action driven size-based filtration approach that enabled cells cultures from the viable CTCs to be unaffected by any antibodies or lysing solutions. The captured cancer cells displayed plasticity which enabled some cells to invade the separating membrane. Further, the cancer cells in the “bottom fraction”, may represent a more invasive CTC-fraction. The CTCs were cultured in vitro for further downstream applications.

CONCLUSION: The presented size-based filtration method enables culture of CTCs in vitro for possible downstream applications.

A targeting ligand enhances infectivity and cytotoxicity of an oncolytic adenovirus in human pancreatic cancer tissues

The addition of a targeting strategy is necessary to enhance oncolysis and secure safety of a conditionally replicative adenovirus (CRAd). We have constructed an adenovirus library displaying random peptides on the fiber, and have successfully identified a pancreatic cancer-targeting ligand (SYENFSA). Here, the usefulness of cancer-targeted CRAd for pancreatic cancer was examined as a preclinical study. First, we constructed a survivin promoter-regulated CRAd expressing enhanced green fluorescent protein gene (EGFP), which displayed the identified targeting ligand (AdSur-SYE). The AdSur-SYE resulted in higher gene transduction efficiency and oncolytic potency than the untargeted CRAd (AdSur) in several pancreatic cancer cell lines. An intratumoral injection of AdSur-SYE significantly suppressed the growth of subcutaneous tumors, in which AdSur-SYE effectively proliferated and spread. An ectopic infection in adjacent tissues and organs of intratumorally injected AdSur-SYE was decreased compared with AdSur. Then, to examine whether the targeting ligand actually enhanced the infectivity of CRAd in human pancreatic cancer tissues, tumor cells prepared from surgical specimens were infected with viruses. The AdSur-SYE increased gene transduction efficiency 6.4-fold higher than did AdSur in single cells derived from human pancreatic cancer, whereas the infectivity of both vectors was almost the same in the pancreas and other cancers. Immunostaining showed that most EGFP(+) cells were cytokeratin-positive in the sliced tissues, indicating that pancreatic cancer cells but not stromal cells were injected with AdSur-SYE. AdSur-SYE resulted in a stronger oncolysis in the primary pancreatic cancer cells co-cultured with mouse embryonic fibroblasts than AdSur did. CRAd in combination with a tumor-targeting ligand is promising as a next-generation of oncolytic virotherapy for pancreatic cancer.

A mathematical model for pancreatic cancer growth and treatments

Pancreatic cancer is one of the most deadly types of cancer and has extremely poor prognosis. This malignancy typically induces only limited cellular immune responses, the magnitude of which can increase with the number of encountered cancer cells. On the other hand, pancreatic cancer is highly effective at evading immune responses by inducing polarization of pro-inflammatory M1 macrophages into anti-inflammatory M2 macrophages, and promoting expansion of myeloid derived suppressor cells, which block the killing of cancer cells by cytotoxic T cells. These factors allow immune evasion to predominate, promoting metastasis and poor responsiveness to chemotherapies and immunotherapies. In this paper we develop a mathematical model of pancreatic cancer, and use it to qualitatively explain a variety of biomedical and clinical data. The model shows that drugs aimed at suppressing cancer growth are effective only if the immune induced cancer cell death lies within a specific range, that is, the immune system has a specific window of opportunity to effectively suppress cancer under treatment. The model results suggest that tumor growth rate is affected by complex feedback loops between the tumor cells, endothelial cells and the immune response. The relative strength of the different loops determines the cancer growth rate and its response to immunotherapy. The model could serve as a starting point to identify optimal nodes for intervention against pancreatic cancer.