Surgical management of early-stage pancreatic cancer

Plasma Extracellular Vesicle Characteristics as Biomarkers of Resectability and Radicality of Surgical Resection in Pancreatic Cancer-A Prospective Cohort Study

Due to possible diagnostic misjudgment of tumor resectability, patients with pancreatic ductal adenocarcinoma (PDAC) might be exposed to non-radical resection or unnecessary laparotomy. With small extracellular vesicles (sEV) obtained by liquid biopsy, we aimed to evaluate their potential as biomarkers of tumor resectability, radicality of resection and overall survival (OS). Our prospective study included 83 PDAC patients undergoing surgery with curative intent followed-up longitudinally. sEV were isolated from plasma, and their concentration and size were determined. Fifty patients underwent PDAC resection, and thirty-three had no resection. Preoperatively, patients undergoing resection had higher sEV concentrations than those without resection (p = 0.023). Resection was predicted at the cutoff value of 1.88 × 10⁹/mL for preoperative sEV concentration (p = 0.023) and the cutoff value of 194.8 nm for preoperative mean diameter (p = 0.057). Furthermore, patients with R0 resection demonstrated higher preoperative plasma sEV concentrations than patients with R1/R2 resection (p = 0.014). If sEV concentration was above 1.88 × 10⁹/mL or if the mean diameter was below 194.8 nm, patients had significantly longer OS (p = 0.018 and p = 0.030, respectively). Our proof-of-principle study identified preoperative sEV characteristics as putative biomarkers of feasibility and radicality of PDAC resection that also enable discrimination of patients with worse OS. Liquid biopsy with sEV could aid in PDAC patient stratification and treatment optimization in the future.

Local radicality and survival outcome of pancreatic cancer surgery

Pancreatic cancer remains a therapeutic challenge. Surgical resection in combination with systemic chemotherapy is the only option promising long-term survival and potential cure. However, only about 20% of patients are diagnosed with tumors that are still in a resectable stage. Even after potentially curative resection and modern regimens for adjuvant chemotherapy, the majority of patients develop local and systemic recurrence resulting in median overall survival times of 28-54 months. The predominance of systemic recurrence and its impact on survival may lead to the assumption that surgical radicality and local control play only minor roles in the treatment of pancreatic cancer. This review provides an overview of the recent literature on surgical radicality and survival outcome in pancreatic cancer. The current evidence on the extent of lymphadenectomy, the prognostic impact of the extent of lymph node involvement, and the impact of the resection margin status on postresection survival are reviewed. Data from recent studies performed in the context of modern surgery and adjuvant therapy provide good evidence of a considerable impact of local radicality on survival after pancreatic cancer surgery. Surgical techniques that have been developed to refine oncological resections and to increase local control as well as resectability are highlighted. These techniques include artery-first approaches, level-3 dissection with removal of the periarterial nerve plexus, the triangle operation, and extended resections. Local radicality and quality of surgical resection remain among the most important parameters that determine the chances for survival in patients with non-metastatic pancreatic cancer.

Neoadjuvant Treatment in Locally Advanced Pancreatic Cancer (LAPC) Patients with FOLFIRINOX or Gemcitabine NabPaclitaxel: A Single-Center Experience and a Literature Review

The optimal therapeutic strategy for locally advanced pancreatic cancer patients (LAPC) has not yet been established. Our aim is to evaluate how surgery after neoadjuvant treatment with either FOLFIRINOX (FFN) or Gemcitabine-NabPaclitaxel (GemNab) affects the clinical outcome in these patients. LAPC patients treated at our institution were retrospectively analysed to reach this goal. The group characteristics were similar: 35 patients were treated with the FOLFIRINOX regimen and 21 patients with Gemcitabine Nab-Paclitaxel. The number of patients undergoing surgery was 14 in the FFN group (40%) and six in the GemNab group (28.6%). The median Disease-Free Survival (DFS) was 77.10 weeks in the FFN group and 58.65 weeks in the Gem Nab group (p = 0.625), while the median PFS in the unresected group was 49.4 weeks in the FFN group and 30.9 in the GemNab group (p = 0.0029, 95% CI 0.138-0.862, HR 0.345). The overall survival (OS) in the resected population needs a longer follow up to be completely assessed, while the median overall survival (mOS) in the FFN group was 72.10 weeks and 53.30 weeks for the GemNab group (p = 0.06) in the unresected population. Surgery is a valuable option for LAPC patients and it is able to induce a relevant survival advantage. FOLFIRINOX and Gem-NabPaclitaxel should be offered as first options to pancreatic cancer patients in the locally advanced setting.

Pancreatic Adenocarcinoma, version 2.2012: featured updates to the NCCN Guidelines

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Pancreatic Adenocarcinoma discuss the workup and management of tumors of the exocrine pancreas. These NCCN Guidelines Insights provide a summary and explanation of major changes to the 2012 NCCN Guidelines for Pancreatic Adenocarcinoma. The panel made 3 significant updates to the guidelines: 1) more detail was added regarding multiphase CT techniques for diagnosis and staging of pancreatic cancer, and pancreas protocol MRI was added as an emerging alternative to CT; 2) the use of a fluoropyrimidine plus oxaliplatin (e.g., 5-FU/leucovorin/oxaliplatin or capecitabine/oxaliplatin) was added as an acceptable chemotherapy combination for patients with advanced or metastatic disease and good performance status as a category 2B recommendation; and 3) the panel developed new recommendations concerning surgical technique and pathologic analysis and reporting.

Hospital and medical care days in pancreatic cancer

BACKGROUND

Little is known about resource utilization (number of days in the hospital or medical care) between diagnosis and death in patients with pancreatic cancer.

METHODS

Using Surveillance, Epidemiology, and End Results (SEER)-Medicare linked data, we identified 25,476 patients with pancreatic cancer (1992-2005). Hospital and medical care days per person-month from the time of diagnosis were described, stratified by stage, treatment, and survival duration.

RESULTS

Hospital/medical care days vary by length of survival and treatment strategy in patients with pancreatic cancer. For all stages, patients were in the hospital a mean of 6.4 days and received medical care a total of 9.0 days in the first month after diagnosis, decreasing to 1.7 and 3.7 days per month, respectively, by the end of the first year. Hospital/medical care days per month of life were higher in patients with shorter survival but increased sharply at the end of life in all patients, regardless of duration of survival. In patients with locoregional disease, resection was associated with a higher number of hospital/medical care days during the first 4 months after diagnosis, but fewer at the end of the first year. For distant disease, hospital days were similar but days in medical care were higher for patients receiving chemotherapy, increasing especially at the end of life.

CONCLUSIONS

This study is the first to quantify hospital/medical care days in patients with pancreatic cancer by stage, treatment, and survival. This information will provide realistic expectations and allow for treatment decisions based on patient preferences.

Gastrectomy and risk of pancreatic cancer: systematic review and meta-analysis of observational studies

PURPOSE

To investigate the association between gastrectomy and risk of pancreatic cancer (PaC).

METHODS

We identified eligible studies in Medline and EMBASE up to 11 February 2012 and the reference lists of original studies and review articles on this topic. Summary relative risks with their 95 % confidence intervals were calculated with a random-effects model. Between-study heterogeneity was assessed using Cochran Q and I (2) statistics.

RESULTS

Fifteen studies (11 case-control studies and 4 cohort studies) met eligibility criteria. The current data suggest that gastrectomy is associated with a 54 % excess risk of PaC (SRRs = 1.54; 95 % CI, 1.25-1.90; test for heterogeneity Q = 17.94, p < 0.001, I (2) = 22 %). There was no publication bias in the present meta-analysis.

CONCLUSION

A significant increased risk of PaC exists in patients who have undergone gastrectomy, particularly those receiving Billroth II resection with a long postoperative interval.

Pancreatic Adenocarcinoma, version 2.2012: featured updates to the NCCN Guidelines

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Pancreatic Adenocarcinoma discuss the workup and management of tumors of the exocrine pancreas. These NCCN Guidelines Insights provide a summary and explanation of major changes to the 2012 NCCN Guidelines for Pancreatic Adenocarcinoma. The panel made 3 significant updates to the guidelines: 1) more detail was added regarding multiphase CT techniques for diagnosis and staging of pancreatic cancer, and pancreas protocol MRI was added as an emerging alternative to CT; 2) the use of a fluoropyrimidine plus oxaliplatin (e.g., 5-FU/leucovorin/oxaliplatin or capecitabine/oxaliplatin) was added as an acceptable chemotherapy combination for patients with advanced or metastatic disease and good performance status as a category 2B recommendation; and 3) the panel developed new recommendations concerning surgical technique and pathologic analysis and reporting.

Advances in biomarker research for pancreatic cancer

Pancreatic cancer (PC) is a leading cause of cancer related deaths in United States. The lack of early symptoms results in latestage detection and a high mortality rate. Currently, the only potentially curative approach for PC is surgical resection, which is often unsuccessful because the invasive and metastatic nature of the tumor masses makes their complete removal difficult. Consequently, patients suffer relapses from remaining cancer stem cells or drug resistance that eventually lead to death. To improve the survival rate, the early detection of PC is critical. Current biomarker research in PC indicates that a serum carbohydrate antigen, CA 19-9, is the only available biomarker with approximately 90% specificity to PC. However, the efficacy of CA 19-9 for assessing prognosis and monitoring patients with PC remains contentious. Thus, advances in technology and the detection of new biomarkers with high specificity to PC are needed to reduce the mortality rate of pancreatic cancer.

Concurrent insulinoma and pancreatic adenocarcinoma: report of a rare case and review of the literature

Pancreatic adenocarcinoma is the 5th leading cause of cancer-related death in Western countries and insulinomas are rare endocrine neoplasms of the pancreas. The concurrent appearance of pancreatic adenocarcinoma and insulinoma is very rare and to the best of our knowledge has never been reported again. Herein, we present such an occurrence in a 74-year-old man. Resection of a mass in the uncinate process of the pancreas revealed pancreatic adenocarcinoma with severe desmoplastic reaction. Two years later, due to symptomatology persistence the patient was re-examined and a new 2cm mass in the uncinate process was found leading to surgery, which demonstrated a 2cm endocrine islet-cell tumor. Establishing a diagnosis in patients with insulinoma is difficult and the imaging studies still have low sensitivity and specificity except for intra-operative ultrasonography, which is the most accurate method detecting 90% of these lesions.

Guidelines for the Surgical Management of Pancreatic Adenocarcinoma

Pancreaticoduodenectomy remains the most formidable operative procedure for the surgical treatment of gastrointestinal malignancy. Improved outcomes after the Whipple procedure have been attributed to better preoperative patient selection, advances in three-dimensional radiographic imaging, and regionalization of referrals to high-volume, tertiary care centers. Despite these advances, morbidity and mortality after pancreaticoduodenectomy are not insignificant and the overall prognosis following resection for adenocarcinoma of the pancreas remains poor. Improvements in endoscopic decompression of malignant biliary obstruction have decreased the need for palliative bypass operations and have focused current surgical issues on ways to improve clinical outcomes following potentially curative resections. Controversies such as whether or not to perform extended lymph node dissections, and standard versus pylorus-preserving resections have been addressed by randomized, prospective clinical trials. Major venous resections secondary to local tumor extension are now performed without an increase in morbidity or mortality and with survival rates comparable to standard resections. This has led to even more aggressive resections following neoadjuvant therapy for lesions previously considered unresectable and now perhaps better categorized as borderline resectable. The impact of surgical specialization and regionalization of referrals to tertiary care centers is evident in markedly improved perioperative mortality rates. This article will attempt to describe current guidelines for the preoperative, intraoperative, and postoperative management of patients with localized pancreatic adenocarcinoma.

EphA4 receptor, overexpressed in pancreatic ductal adenocarcinoma, promotes cancer cell growth

To isolate novel diagnostic markers and drug targets for pancreatic ductal adenocarcinoma (PDAC), we previously performed expression profile analysis of PDAC cells using a genome-wide cDNA microarray combined with laser microdissection. Among dozens of up-regulated genes identified in PDAC cells, we herein focused on one tyrosine kinase receptor, Eph receptor A4 (EphA4), as a molecular target for PDAC therapy. Immunohistochemical analysis validated EphA4 overexpression in approximately half of the PDAC tissues. To investigate its biological function in PDAC cells, we knocked down EphA4 expression by siRNA, which drastically attenuated PDAC cell viability. In concordance with the siRNA experiment, PDAC-derivative cells that were designed to constitutively express exogenous EphA4 showed a more rapid growth rate than cells transfected with mock vector, suggesting a growth-promoting effect of EphA4 on PDAC cells. Furthermore, the expression analysis for ephrin ligand family members indicated the coexistence of ephrinA3 ligand in PDAC cells with EphA4 receptor, and knockdown of ephrinA3 by siRNA also attenuated PDAC cell viability. These results suggest that the EphA4-ephrinA3 pathway is likely to be a promising molecular target for pancreatic cancer therapy.

Differential gene expression in patients genetically predisposed to pancreatic cancer

BACKGROUND

Nearly 10% of all pancreatic cancer (PCA) results from genetic predisposition. Although abnormalities in sporadic PCA have been described, little is known about the genetics of heritable PCA. The purpose of this study was to identify novel genes expressed in patients with a presumed genetic predisposition or "familial" PCA.

PATIENTS AND METHODS

We defined "familial" PCA as patients having one or more first-degree relatives with biopsy-proven adenocarcinoma of the pancreas. Using a PCR-based subtractive and enrichment procedure, representational difference analysis (RDA), pancreatic tumor cDNA was reverse-transcribed from pooled poly(A)+ mRNA from six such patients (tester) and compared to pooled cDNA from five normal pancreata (driver). Tumor-specific gene fragments were identified and confirmed to be overexpressed in familial PCA by comparative RT-PCR. Six PCA cell lines, 11 sporadic tumors, 5 neuroendocrine tumors, and 3 chronic pancreatitis tissues were screened to determine the specificity of these genes.

RESULTS

Sequence analysis revealed several sequences of unknown significance and six genes previously described in neoplasia/carcinogenesis: Apolipoprotein A4, CEA, Keratin 19, Stratifin (14-3-3 sigma), Trefoil Factor, and Calcium Binding Protein S100 A6. Screening of cell lines and pancreatic tissue types showed varying degrees of specificity for familial and sporadic PCA. The APO-A4 gene was up-regulated in familial PCA.

CONCLUSIONS

The pattern of frequency in all screened tissue suggests that these genes are associated with conditions that produce significant desmoplastic responses and are difficult to differentiate from chronic inflammatory processes. Apolipoprotein A4 is preferentially expressed in familial patients, suggesting that the importance of fatty acid synthesis in carcinogenesis be investigated further.

EGF receptor antagonism improves survival in a murine model of pancreatic adenocarcinoma

INTRODUCTION

The purpose of this study was to determine whether inhibition of the epidermal growth factor receptor (EGFR) is a plausible therapeutic strategy in pancreatic cancer.

METHODS

A human pancreatic cancer cell line (HPAC) was evaluated for the presence of EGFR with rtPCR and immunohistochemistry. Cells were grown in the presence of either 50 or 100 microM of erlotinib (EGFRI) for 72 hours and evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Eighty-six athymic nude/nude mice underwent orthotopic implantation of 10(7) HPAC cells and were blindly randomized into four groups: (1) Control; (2) Batimastat, a matrix metalloproteinase inhibitor (MMPI) at 400 ng/ml qod; (3) EGFRI at 100 mg/kg qd; and (4) MMPI and EGRRI (both). In vitro and in vivo effects of EGFRI with and without MMPI were compared.

RESULTS

HPAC demonstrated high levels of expression of both the EGFR gene and the gene product. In vitro, both doses of EGFRI significantly reduced proliferation of HPAC at 48 (50 microM: 1.15 + 0.05 [st dev] versus 0.63 + 0.09 abs, P < 0.001) and 72 h (50 microM: 1.48 +/- 0.09 versus 0.73 +/- 0.05 abs, P < 0.001, paired Student's t-test). In vivo, each treatment group demonstrated a significant survival advantage (P = 0.0002 group 2, P = 0.0001 group 3, P = 0.012 group 4, log rank test) over controls. Mice treated with EGFRI showed reduced tumor implantation, size, weight, metastatic potential, and jaundice as compared to controls and MMPI-treated mice (all P < 0.05, Fisher's exact test).

CONCLUSION

EGF receptor antagonism is not only a plausible therapy for treatment of ductal adenocarcinoma of the pancreas, but is also superior to matrix metalloproteinase inhibition alone or in combination.

Prognostic significance of new onset ascites in patients with pancreatic cancer

Background

The purpose of this study was to determine risk factors for development of malignant ascites and its prognostic significance in patients with pancreatic cancer.

Methods

A prospective database was queried to identify patients with pancreatic cancer who develop ascites. Stage at presentation, size, and location of primary tumor, treatment received and length of survival after onset of ascites were determined.

Results

A total of 15 patients were identified. Of which 4 patients (1 stage II, 3 stage III) underwent pancreaticoduodenectomy and manifested with ascites 2, 3, 24 and 47 months after surgery (tumor size 2.9 ± 1.32 cm). All but one of the remaining 11 patients (tumor size 4.4 ± 3.38 cm) presented with metastatic disease, and all developed malignant ascites 9 months after diagnosis, dying 2 months later. Resected patients lived longer before the onset of ascites, but not after.

Conclusion

Once diagnosed, ascites in pancreatic cancer patients heralds imminent death. Limited survival should be considered when determining the aggressiveness of further intervention.

Cytokeratin 20 expression identifies a subtype of pancreatic adenocarcinoma with decreased overall survival

BACKGROUND

Cytokeratins are markers of epithelial cell differentiation useful in determining histogenesis for malignancies with an unknown primary. Application of this principle to a single malignancy may identify cancer subtypes with altered developmental programs. Herein, we investigate the relevance of two widely used cytokeratins (CKs), 7 and 20, to subtype pancreas cancer and identify associations with clinical features.

METHODS

A tissue microarray was constructed using tumor specimens from 103 patients who underwent resection for pancreatic adenocarcinoma with curative intent. A subset of resection specimens was evaluated for pancreatic intraepithelial neoplasia (PanIN) lesions. Tissues were immunostained by using specific anticytokeratin 7 and 20 monoclonal antibodies.

RESULTS

CK 7 and 20 expression was present in 96% and 63% cases of pancreatic adenocarcinoma, respectively. Ubiquitous CK 7 expression precluded further analysis. Tumoral CK 20 expression was not associated with any histopathologic parameter but correlated with worse prognosis when considered as either a dichotomous (P=0.0098) or continuous (P=0.007) variable. In a multivariate model, tumoral CK 20 expression remained a significant independent prognosticator. CK 20 expression was absent in all PanIN lesions from eight resection specimens in which the tumor component was negative for CK 20. In contrast, presence of tumoral CK 20 was highly concordant with its expression in corresponding PanINs.

CONCLUSIONS

CK 20 expression defines a subtype of pancreas cancer with important biologic properties. When present, CK 20 expression is an early event in pancreatic carcinogenesis identifiable in precursor lesions. Further studies to identify the underlying genetic changes associated with this altered developmental pathway are warranted.

CEACAM6 is a novel biomarker in pancreatic adenocarcinoma and PanIN lesions

OBJECTIVE

The purpose of this study was to test the hypothesis that CEACAM6 expression is an indicator of adverse pathologic features and clinical outcome in pancreatic adenocarcinoma.

SUMMARY BACKGROUND DATA

Previously, we have demonstrated carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) to be an oncoprotein that plays an important role in the biology of pancreatic adenocarcinoma. Suppression of CEACAM6 expression reduces tumorigenesis and metastasis in vivo.

METHODS

A tissue microarray was constructed using tumor specimens obtained from 89 consecutive patients who had undergone pancreatic resection for pancreatic adenocarcinoma with curative intent. A second microarray containing 54 pancreatic intraepithelial neoplasia (PanIN) lesions was constructed using tissues from a separate cohort of 44 patients. Both arrays were immunostained using a specific anti-CEACAM6 monoclonal antibody. Tumoral CEACAM6 expression was dichotomized into negative and positive immunoreactivity groups. The log-rank test was used to evaluate univariate associations of CEACAM6 expression with prognosis. Survival curves were derived using the Kaplan-Meier method.

RESULTS

Tumoral CEACAM6 expression was detected in 82 (92%) pancreatic adenocarcinoma specimens. CEACAM6 expression was more prevalent in high-grade than in low-grade PanIN lesions (P = 0.0002). Negative tumoral CEACAM6 expression was associated with absence of lymph node metastases (P = 0.012), lower disease stage (P = 0.008), and longer postoperative survival (P = 0.047).

CONCLUSIONS

CEACAM6 is a novel biomarker for pancreatic adenocarcinoma. CEACAM6 warrants further evaluation as both a prognostic factor and a therapeutic target in pancreatic cancer.