DPC4 gene status of the primary carcinoma correlates with patterns of failure in patients with pancreatic cancer

Tumor-stromal interactions in pancreatic cancer

The tumor associated stroma has been described in recent years as being complicit in tumor growth in pancreatic cancer. The stroma hosts a variety of components of both cellular and molecular makeup. In normal tissues, the stroma provides nutrients and regulatory signals for proper cellular polarity and function. However, following oncogenic transformation, the stromal compartment is conscripted to provide stimulatory signals and protection to tumor cells. It is these tumor-stromal interactions that are currently of great therapeutic interest. Several key reports have suggested that therapeutic targeting of the tumor-stromal interactions in pancreatic cancer has the potential to offer survival benefit. In this review, we will discuss the tumor-stromal interactions that contribute to tumor growth and progression, and ways in which we might counter these interactions.

Prognostic significance of carbohydrate antigen 19-9 in unresectable locally advanced pancreatic cancer treated with dose-escalated intensity modulated radiation therapy and concurrent full-dose gemcitabine: analysis of a prospective phase 1/2 dose escalation study

PURPOSE

Although established in the postresection setting, the prognostic value of carbohydrate antigen 19-9 (CA19-9) in unresectable locally advanced pancreatic cancer (LAPC) is less clear. We examined the prognostic utility of CA19-9 in patients with unresectable LAPC treated on a prospective trial of intensity modulated radiation therapy (IMRT) dose escalation with concurrent gemcitabine.

METHODS AND MATERIALS

Forty-six patients with unresectable LAPC were treated at the University of Michigan on a phase 1/2 trial of IMRT dose escalation with concurrent gemcitabine. CA19-9 was obtained at baseline and during routine follow-up. Cox models were used to assess the effect of baseline factors on freedom from local progression (FFLP), distant progression (FFDP), progression-free survival (PFS), and overall survival (OS). Stepwise forward regression was used to build multivariate predictive models for each endpoint.

RESULTS

Thirty-eight patients were eligible for the present analysis. On univariate analysis, baseline CA19-9 and age predicted OS, CA19-9 at baseline and 3 months predicted PFS, gross tumor volume (GTV) and black race predicted FFLP, and CA19-9 at 3 months predicted FFDP. On stepwise multivariate regression modeling, baseline CA19-9, age, and female sex predicted OS; baseline CA19-9 and female sex predicted both PFS and FFDP; and GTV predicted FFLP. Patients with baseline CA19-9 ≤ 90 U/mL had improved OS (median 23.0 vs 11.1 months, HR 2.88, P<.01) and PFS (14.4 vs 7.0 months, HR 3.61, P=.001). CA19-9 progression over 90 U/mL was prognostic for both OS (HR 3.65, P=.001) and PFS (HR 3.04, P=.001), and it was a stronger predictor of death than either local progression (HR 1.46, P=.42) or distant progression (HR 3.31, P=.004).

CONCLUSIONS

In patients with unresectable LAPC undergoing definitive chemoradiation therapy, baseline CA19-9 was independently prognostic even after established prognostic factors were controlled for, whereas CA19-9 progression strongly predicted disease progression and death. Future trials should stratify by baseline CA19-9 and incorporate CA19-9 progression as a criterion for progressive disease.

Pathology and Genetics of Pancreatic Neoplasms

This is a state-of-the-art review of the molecular genetics of pancreatic neoplasms. Although understanding of the molecular features underlying pancreatic neoplasms is still in its infancy, a strong emphasis on the relevance of these findings for the practicing surgical pathologist is provided. The application of molecular techniques has yielded a wealth of information that may soon enhance diagnostics, and will also lead to the development of safer, more effective targeted therapies. The pathologist will play a key role in integrating the current pathologic classification system with newly validated molecular markers.

Irreversible electroporation in locally advanced pancreatic cancer: potential improved overall survival

BACKGROUND

Locally advanced unresectable pancreatic adenocarcinoma (LAC) is characterized by poor survival despite chemotherapy and conventional radiation therapy. We have recently reported on the safety of using irreversible electroporation (IRE) for the management of LAC. The purpose of this study was to evaluate the overall survival in patients with LAC treated with IRE.

METHODS

A prospective, multi-institutional evaluation of 54 patients who underwent IRE for unresectable pancreatic cancer from December 2009 to October 2010 was evaluated for overall survival and propensity matched to 85 matched stage III patients treated with standard therapy defined as chemotherapy and radiation therapy alone.

RESULTS

A total of 54 LAC patients have undergone IRE successfully, with 21 women, 23 men (median age, 61 (range, 45-80) years). Thirty-five patients had pancreatic head primary and 19 had body tumors; 19 patients underwent margin accentuation with IRE and 35 underwent in situ IRE. Forty-nine (90 %) patients had pre-IRE chemotherapy alone or chemoradiation therapy for a median duration 5 months. Forty (73%) patients underwent post-IRE chemotherapy or chemoradiation. The 90 day mortality in the IRE patients was 1 (2 %). In a comparison of IRE patients to standard therapy, we have seen an improvement in local progression-free survival (14 vs. 6 months, p = 0.01), distant progression-free survival (15 vs. 9 months, p = 0.02), and overall survival (20 vs. 13 months, p = 0.03).

CONCLUSIONS

IRE ablation of locally advanced pancreatic tumors remains safe and in the appropriate patient who has undergone standard induction therapy for a minimum of 4 months can achieve greater local palliation and potential improved overall survival compared with standard chemoradiation-chemotherapy treatments. Validation of these early results will need to be validated in the current multi-institutional Phase 2 IDE study.

Human correlates of provocative questions in pancreatic pathology

Studies of cell lines and of animal models of pancreatic cancer have raised a number of provocative questions about the nature and origins of human pancreatic cancer and have provided several leads into exciting new approaches for the treatment of this deadly cancer. In addition, clinicians with little or no contact with human pathology have challenged the way that pancreatic pathology is practiced, suggesting that "genetic signals" may be more accurate than today's multimodal approach to diagnoses. In this review, we consider 8 provocative issues in pancreas pathology, with an emphasis on "the evidence derived from man."

Overview of whole body gamma knife for locally advanced pancreatic cancer

Pancreatic cancer is a disease that seriously threatens the health of human beings. The treatment options currently available for pancreatic cancer are still limited. In this article, we describe the principle of whole body gamma knife and SBRT (a treatment similar to whole body gamma knife) for the treatment of advanced pancreatic cancer. By improving the absorbed dose in the lesion, whole body gamma knife can control tumor progression and improve survival in patients with pancreatic cancer with low side effects. Despite that controversy still exists, the advantages of SBRT in the treatment of pancreatic cancer have been gradually recognized in foreign countries.

Dose-painted intensity modulated radiation therapy improves local control for locally advanced pancreas cancer

Background. To evaluate the outcomes, adverse events, and therapeutic role of Dose-Painted Intensity-Modulated Radiation Therapy (DP-IMRT) for locally advanced pancreas cancer (LAPC). Methods. Patients with LAPC were treated with induction chemotherapy (n = 25) and those without metastasis (n = 20) received DP-IMRT consisting of 45 Gy to Planning Treatment Volume 1 (PTV1) including regional lymph nodes with a concomitant boost to the PTV2 (gross tumor volume + 0.5 cm) to either 50.4 Gy (n = 9) or 54 Gy (n = 11) in 25 fractions. DP-IMRT cases were compared to three-dimensional conformal radiation therapy (3D-CRT) plans to assess the potential relationship of radiation dose to adverse events. Kaplan-Meier and Cox regression analyses were used to calculate survival probabilities. The Fisher exact test and t-test were utilized to investigate potential prognostic factors of toxicity and survival. Results. Median overall and progression-free survivals were 11.6 and 5.9 months, respectively. Local control was 90%. Post-RT CA-19-9 levels following RT were predictive of survival (P = 0.02). Grade 2 and ≥grade 3 GI toxicity were 60% and 20%, respectively. In comparison to 3D-CRT, DP-IMRT plans demonstrated significantly lower V45 values of small bowel (P = 0.0002), stomach (P = 0.007), and mean liver doses (P = 0.001). Conclusions. Dose-escalated DP-IMRT offers improved local control in patients treated with induction chemotherapy for LAPC. Radiation-related morbidity appears reduced with DP-IMRT compared to 3D-CRT techniques, likely due to reduction in RT doses to organs at risk.

Clinical significance of the genetic landscape of pancreatic cancer and implications for identification of potential long-term survivors

PURPOSE

Genetic alterations of KRAS, CDKN2A, TP53, and SMAD4 are the most frequent events in pancreatic cancer. We determined the extent to which these 4 alterations are coexistent in the same carcinoma, and their impact on patient outcome.

EXPERIMENTAL DESIGN

Pancreatic cancer patients who underwent an autopsy were studied (n = 79). Matched primary and metastasis tissues were evaluated for intragenic mutations in KRAS, CDKN2A, and TP53 and immunolabeled for CDKN2A, TP53, and SMAD4 protein products. The number of altered driver genes in each carcinoma was correlated to clinicopathologic features. Kaplan-Meier estimates were used to determine median disease free and overall survival, and a Cox proportional hazards model used to compare risk factors.

RESULTS

The number of genetically altered driver genes in a carcinoma was variable, with only 29 patients (37%) having an alteration in all 4 genes analyzed. The number of altered driver genes was significantly correlated with disease free survival (P = 0.008), overall survival (P = 0.041), and metastatic burden at autopsy (P = 0.002). On multivariate analysis, the number of driver gene alterations in a pancreatic carcinoma remained independently associated with overall survival (P = 0.046). Carcinomas with only 1 to 2 driver alterations were enriched for those patients with the longest survival (median 23 months, range 1 to 53).

CONCLUSIONS

Determinations of the status of the 4 major driver genes in pancreatic cancer, and specifically the extent to which they are coexistent in an individual patients cancer, provides distinct information regarding disease progression and survival that is independent of clinical stage and treatment status.

Radiation dose ≥54 Gy and CA 19-9 response are associated with improved survival for unresectable, non-metastatic pancreatic cancer treated with chemoradiation

BACKGROUND

Unresectable pancreatic cancer (UPC) has low survival. With improving staging techniques and systemic therapy, local control in patients without metastatic disease may have increasing importance. We investigated whether the radiation dose used in chemoradiation (CRT) as definitive treatment for UPC and the CA 19-9 response to therapy have an impact on overall survival (OS).

METHODS

From 1997-2009 46 patients were treated with CRT for non-metastatic UPC. Median prescribed RT dose was 54 Gy (range 50.4-59.4 Gy). All patients received concurrent chemotherapy (41: 5-fluorouracil, 5: other) and 24 received adjuvant chemotherapy.

RESULTS

41 patients were inoperable due to T4 disease and 5 patients with T3 disease were medically inoperable. Five patients did not complete CRT due to progressive disease or treatment-related toxicity (median RT dose 43.2 Gy). Overall, 42 patients were dead of disease at the time of last follow-up. The median and 12 month OS were 8.8 months and 35%, respectively. By univariate analysis, minimum CA 19-9 post-CRT <90 U/mL was favorably associated with OS (12.3 versus 8.8 months, p = 0.012). Radiotherapy dose ≥54 Gy trended towards improved OS (11.3 versus 6.8 months, p = 0.089). By multivariable analysis, a delivered RT dose of ≥54 Gy (HR 0.47, p = 0.028) and minimum CA 19-9 post-CRT of <90 U/mL (HR 0.35, p = 0.008) were associated with OS.

CONCLUSIONS

CRT as definitive treatment for UPC had low survival. However, our retrospective data suggest that patients treated to ≥54 Gy or observed to have a minimum post-CRT CA 19-9 <90 U/mL had improved likelihood of long-term survival.

Clinical implications of biological markers in Pancreatic Ductal Adenocarcinoma

Pancreatic Ductal Adenocarcinoma (PDAC) is a malignant neoplasm and is the fourth leading cause of cancer-related deaths in US with a 5-year survival rate less than 5%. Surgery is the only potentially curative treatment even though the result is a palliation in the majority of cases and the majority of lesions are lately diagnosed. Progression from normal pancreatic epithelium to metastatic disease is now a well-characterized sequence of events. Research has shown that pancreatic cancer is fundamentally a genetic disease with several biological pathway implied in apoptosis, cell proliferation and self-sufficiency in growth signaling, but how those findings could be applied in daily clinical practice remain unknown. Several studies tried to characterize diagnostic and prognostic biomarkers in PDAC to make it possible an earlier diagnosis, guarantee a more effective treatment and reach a better prognosis even though the results remain contrasting. The main limit of the published researches is the small number of patients studied, but even the heterogeneity of the used methods of analysis. Examining critically the research of the last years future trials may be addressed toward a translational models integrating "the bench and the bed" with the clinical experience and drive the basic research toward the clinical applications.

Contribution of CXCR4 and SMAD4 in predicting disease progression pattern and benefit from adjuvant chemotherapy in resected pancreatic adenocarcinoma

BACKGROUND

Prognosis of patients with pancreatic adenocarcinoma is poor. Many prognostic biomarkers have been tested, but most studies included heterogeneous patients. We aimed to investigate the prognostic and/or predictive values of four relevant biomarkers in a multicentric cohort of patients.

PATIENTS AND METHODS

A total of 471 patients who had resected pancreatic adenocarcinoma were included. Using tissue microarray, we assessed the relationship of biomarker expressions with the overall survival: Smad4, type II TGF-β receptor, CXCR4, and LKB1.

RESULTS

High CXCR4 expression was found to be the only independent negative prognostic biomarker [hazard ratio (HR) = 1.74; P < 0.0001]. In addition, it was significantly associated with a distant relapse pattern (HR = 2.19; P < 0.0001) and was the strongest prognostic factor compared with clinicopathological factors. In patients who did not received adjuvant treatment, there was a trend toward decrease in the overall survival for negative Smad4 expression. Loss of Smad4 expression was not correlated with recurrence pattern but was shown to be predictive for adjuvant chemotherapy (CT) benefit (HR = 0.59; P = 0.002).

CONCLUSIONS

CXCR4 is a strong independent prognostic biomarker associated with distant metastatic recurrence and appears as an attractive target to be evaluated in pancreatic adenocarcinoma. Negative SMAD4 expression should be considered as a potential predictor of adjuvant CT benefit.

Preoperative therapies for resectable and borderline resectable pancreatic cancer

In the era of multidetector high quality CT imaging, it is feasible and critical to use objective criteria to define resectable pancreatic cancer. This allows accurate pretreatment staging and the development of stage-specific therapy. Tumors of borderline resectability have emerged as a distinct subset and the definition has been expanded in the last few years. Borderline resectable tumors are defined as those with tumor abutment of <180degrees (< 50%) of the SMA or celiac axis, short segment abutment or encasement of the common hepatic artery typically at the gastroduodenal artery origin, SMV-PV abutment with impingement and narrowing or segmental venous occlusion with sufficient venous flow above and below the occlusion to allow an option for venous reconstruction. Most of the patients whose cancer meet these CT criteria are candidates for preoperative systemic chemotherapy followed by chemoradiation since they are at a high risk for margin positive resection with upfront surgery. Patients whose imaging studies show radiographic stability or regression proceed to pancreaticoduodenectomy (or pancreatectomy) and this may require vascular resection and reconstruction. Prospective biomarker and functional imaging enriched studies are warranted to determine the best overall treatment strategy for these patients.

The role of chemoradiation for patients with resectable or potentially resectable pancreatic cancer

Conflicting data and substantial controversy exist regarding optimal adjuvant treatment for those patients with resectable or potentially resectable adenocarcinoma of the pancreas. Despite improvements in short-term surgical outcomes, the use of newer chemotherapeutic agents, development of targeted agents and more precise delivery of radiation, the 5-year survival rates for early-stage patients remains less than 25%. This article critically reviews the existing data for various adjuvant treatment approaches for patients with surgically resectable pancreatic cancer. Our review confirms that despite several randomized clinical trials, the optimal adjuvant treatment approach for these patients remains unclear.

Adjuvant therapy for pancreas adenocarcinoma

Adjuvant therapy for pancreas adenocarcinoma in 2012 includes consideration of systemic therapy based on high level evidence and combined chemoradiotherapy based on less robust data. Current major adjuvant questions are examining the role of the addition of a second agent, either cytotoxic or targeted agent, to gemcitabine and whether or not the utilization of combined chemoradiotherapy improves overall survival. Progress to date has been modest and incremental in the adjuvant setting.

Molecular pathways in pancreatic carcinogenesis

Pancreatic cancer is a genetic disease. Pancreatic cancers develop from one of three precursor lesions, pancreatic intraepithelial neoplasia (PanIN), intraductal papillary mucinous neoplasms (IPMNs), and mucinous cystic neoplasms (MCNs), and each arises in association with distinct genetic alterations. These alterations not only provide insight into the fundamental origins of pancreatic cancer but provide ample opportunity for improving early diagnosis and management of cystic precursors.

Genetically defined subsets of human pancreatic cancer show unique in vitro chemosensitivity

PURPOSE

Pancreatic cancer is the fourth cause of death from cancer in the western world. Majority of patients present with advanced unresectable disease responding poorly to most chemotherapeutic agents. Chemotherapy for pancreatic cancer might be improved by adjusting it to individual genetic profiles. We attempt to identify genetic predictors of chemosensitivity to broad classes of anticancer drugs.

EXPERIMENTAL DESIGN

Using a panel of genetically defined human pancreatic cancer cell lines, we tested gemcitabine (antimetabolite), docetaxel (antimicrotubule), mitomycin C (MMC; alkylating), irinotecan (topoisomerase I inhibitor), cisplatin (crosslinking), KU0058948 (Parp1 inhibitor), triptolide (terpenoid drug), and artemisinin (control).

RESULTS

All pancreatic cancer cell lines were sensitive to triptolide and docetaxel. Most pancreatic cancer cells were also sensitive to gemcitabine and MMC. The vast majority of pancreatic cancer cell lines were insensitive to cisplatin, irinotecan, and a Parp1 inhibitor. However, individual cell lines were often sensitive to these compounds in unique ways. We found that DPC4/SMAD4 inactivation sensitized pancreatic cancer cells to cisplatin and irinotecan by 2- to 4-fold, but they were modestly less sensitive to gemcitabine. Pancreatic cancer cells were all sensitive to triptolide and 18% were sensitive to the Parp1 inhibitor. P16/CDKN2A-inactivated pancreatic cancer cells were 3- to 4-fold less sensitive to gemcitabine and MMC.

CONCLUSIONS

Chemosensitivity of pancreatic cancer cells correlated with some specific genetic profiles. These results support the hypothesis that genetic subsets of pancreatic cancer exist, and these genetic backgrounds may permit one to personalize the chemotherapy of pancreatic cancer in the future. Further work will need to confirm these responses and determine their magnitude in vivo.

Diagnostic, prognostic, and predictive biomarkers in pancreatic cancer

Serum CA 19-9 is the only FDA approved biomarker recommended for use in the routine management of pancreatic ductal adenocarcinoma (PDA). Over 2,000 biomarker studies related to pancreatic cancer appear in the literature, highlighting the need to discover and develop improved tests. Diagnostic biomarkers have implications for early detection of PDA, prognostic markers predict patient survival and recurrence patterns, and predictive markers can help personalize treatment regimens.

Inhibition of non-homologous end joining repair impairs pancreatic cancer growth and enhances radiation response

Pancreatic ductal adenocarcinoma (PDAC) is amongst the deadliest of human cancers, due to its late diagnosis as well as its intense resistance to currently available therapeutics. To identify mechanisms as to why PDAC are refractory to DNA damaging cytoxic chemotherapy and radiation, we performed a global interrogation of the DNA damage response of PDAC. We find that PDAC cells generally harbor high levels of spontaneous DNA damage. Inhibition of Non-Homologous End Joining (NHEJ) repair either pharmacologically or by RNAi resulted in a further accumulation of DNA damage, inhibition of growth, and ultimately apoptosis even in the absence of exogenous DNA damaging agents. In response to radiation, PDAC cells rely on the NHEJ pathway to rapidly repair DNA double strand breaks. Mechanistically, when NHEJ is inhibited there is a compensatory increase in Homologous Recombination (HR). Despite this upregulation of HR, DNA damage persists and cells are significantly more sensitive to radiation. Together, these findings support the incorporation of NHEJ inhibition into PDAC therapeutic approaches, either alone, or in combination with DNA damaging therapies such as radiation.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

The deubiquitinase USP9X suppresses pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDA) remains a lethal malignancy despite much progress concerning its molecular characterization. PDA tumours harbour four signature somatic mutations in addition to numerous lower frequency genetic events of uncertain significance. Here we use Sleeping Beauty (SB) transposon-mediated insertional mutagenesis in a mouse model of pancreatic ductal preneoplasia to identify genes that cooperate with oncogenic Kras(G12D) to accelerate tumorigenesis and promote progression. Our screen revealed new candidate genes for PDA and confirmed the importance of many genes and pathways previously implicated in human PDA. The most commonly mutated gene was the X-linked deubiquitinase Usp9x, which was inactivated in over 50% of the tumours. Although previous work had attributed a pro-survival role to USP9X in human neoplasia, we found instead that loss of Usp9x enhances transformation and protects pancreatic cancer cells from anoikis. Clinically, low USP9X protein and messenger RNA expression in PDA correlates with poor survival after surgery, and USP9X levels are inversely associated with metastatic burden in advanced disease. Furthermore, chromatin modulation with trichostatin A or 5-aza-2'-deoxycytidine elevates USP9X expression in human PDA cell lines, indicating a clinical approach for certain patients. The conditional deletion of Usp9x cooperated with Kras(G12D) to accelerate pancreatic tumorigenesis in mice, validating their genetic interaction. We propose that USP9X is a major tumour suppressor gene with prognostic and therapeutic relevance in PDA.

A phase I/II trial of intensity modulated radiation (IMRT) dose escalation with concurrent fixed-dose rate gemcitabine (FDR-G) in patients with unresectable pancreatic cancer

PURPOSE

Local failure in unresectable pancreatic cancer may contribute to death. We hypothesized that intensification of local therapy would improve local control and survival. The objectives were to determine the maximum tolerated radiation dose delivered by intensity modulated radiation with fixed-dose rate gemcitabine (FDR-G), freedom from local progression (FFLP), and overall survival (OS).

METHODS AND MATERIALS

Eligibility included pathologic confirmation of adenocarcinoma, radiographically unresectable, performance status of 0-2, absolute neutrophil count of ≥ 1,500/mm(3), platelets ≥ 100,000/mm(3), creatinine <2 mg/dL, bilirubin <3 mg/dL, and alanine aminotransferase/aspartate aminotransferase ≤ 2.5 × upper limit of normal. FDR-G (1000 mg/m(2)/100 min intravenously) was given on days -22 and -15, 1, 8, 22, and 29. Intensity modulated radiation started on day 1. Dose levels were escalated from 50-60 Gy in 25 fractions. Dose-limiting toxicity was defined as gastrointestinal toxicity grade (G) ≥ 3, neutropenic fever, or deterioration in performance status to ≥ 3 between day 1 and 126. Dose level was assigned using TITE-CRM (Time-to-Event Continual Reassessment Method) with the target dose-limiting toxicity (DLT) rate set to 0.25.

RESULTS

Fifty patients were accrued. DLTs were observed in 11 patients: G3/4 anorexia, nausea, vomiting, and/or dehydration (7); duodenal bleed (3); duodenal perforation (1). The recommended dose is 55 Gy, producing a probability of DLT of 0.24. The 2-year FFLP is 59% (95% confidence interval [CI]: 32-79). Median and 2-year overall survival are 14.8 months (95% CI: 12.6-22.2) and 30% (95% CI 17-45). Twelve patients underwent resection (10 R0, 2 R1) and survived a median of 32 months.

CONCLUSIONS

High-dose radiation therapy with concurrent FDR-G can be delivered safely. The encouraging efficacy data suggest that outcome may be improved in unresectable patients through intensification of local therapy.

Role of radiation therapy in the management of pancreatic cancer

Local failure remains a major issue for patients with both resectable and locally advanced pancreatic cancer. The role of radiation therapy in the management of this disease is less clear and represents an area of some controversy. The objective of this review is to present the rationale for radiation therapy in pancreatic cancer, as well as to discuss the potential limitations and caveats of the currently available studies.

Evaluation of predictive variables in locally advanced pancreatic adenocarcinoma patients receiving definitive chemoradiation

PURPOSE

To analyze a single-center experience with locally advanced pancreatic cancer (LAPC) patients treated with chemoradiation (CRT) and to evaluate predictive variables of outcome.

METHODS AND MATERIALS

LAPC patients at our institution between 1997 and 2009 were identified (n = 109). Progression-free survival (PFS) and overall survival (OS) were assessed using Kaplan-Meier analysis. Cox proportional hazard models were used to evaluate predictive factors for survival. Patterns of failure were characterized, and associations between local progression and distant metastasis were explored.

RESULTS

Median OS was 12.1 months (2.5-34.7 months) and median PFS was 6.7 months (1.1-34.7 months). Poor prognostic factors for OS include Karnofsky performance status ≤80 (P = .0062), treatment interruption (P = .0474), and locally progressive disease at time of first post-therapy imaging (P = .0078). Karnofsky performance status ≤80 (P = .0128), pretreatment CA19-9 >1000 U/mL (P = .0224), and treatment interruption (P = .0009) were poor prognostic factors for PFS. Both local progression (36%) and distant failure (62%) were common. Local progression was associated with a higher incidence of metastasis (P < .0001) and decreased time to metastasis (P < .0001).

CONCLUSIONS

LAPC patients who suffer local progression following definitive CRT may experience inferior OS and increased risk of metastasis, warranting efforts to improve control of local disease. However, patients with poor pretreatment performance status, elevated CA19-9 levels, and treatment interruptions may experience poor outcomes despite aggressive management with CRT, and may optimally be treated with induction chemotherapy or supportive care. Novel therapies aimed at controlling both local and systemic progression are needed for patients with LAPC.

Radiotherapy in the adjuvant management of pancreatic adenocarcinoma: is it helpful?

Curative-intent management for pancreatic adenocarcinoma requires gross total resection. Only 15-20% of patients are eligible for resection and of these only approximately 20% are long-term survivors. Adjuvant and neoadjuvant approaches have been, and are being, sought to improve upon surgical results. Radiotherapy has a role in the adjuvant management of many gastrointestinal malignancies and historically has also had a role in the adjuvant management of pancreatic adenocarcinoma. However, the role of radiotherapy in the management of pancreatic adenocarcinoma has been called into question. This review examines this controversy and the underlying issues and considers current efforts towards resolving them, as well as some likely future developments.

Combined modality treatments in pancreatic cancer

INTRODUCTION

Of all the carcinomas, pancreatic carcinoma (PC) has the highest mortality rate, with a 1- and 5-year survival rate of 25% and less than 5% respectively. This is regardless of the stage at diagnosis.

AREAS COVERED

In this review relevant literature assessing the evidence regarding preoperative and adjuvant chemoradiotherapy (CRT) is discussed. Furthermore, new therapeutic approaches are summarized, while the future direction regarding the multimodality approach to PC is also discussed.

EXPERT OPINION

The role of combined-modality therapy for PC is continuously evolving. There have been several recent developments, as well as the completion of major, multi-institutional clinical trials. One of the challenges for the busy clinician is to appreciate the variation in staging, surgical expertise, and application of either definitive CRT or neo-adjuvant CRT for local and/or borderline disease.

Energy metabolism and proliferation in pancreatic carcinogenesis

INTRODUCTION

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer entity with a high proliferative potential. Uncontrolled cell proliferation is mediated by a number of core signaling pathways. Recently, novel data of PDAC biology suggest that these core signal pathways affect cell proliferation and metabolism simultaneously.

METHODS

Here, we reviewed the literature on core metabolic signaling pathways in pancreatic carcinogenesis.

RESULTS

Results obtained from mouse genetics and in vitro experiments have demonstrated the significance of the Kras, p53, c-Myc, and Lkb1 networks in the proliferation of pancreatic epithelial and cancer cells. At the same time, these major pathways also affect energy metabolism by influencing glucose and glutamine utilization. In particular, Kras-mediated metabolic changes seem to be directly involved in carcinogenesis. However, there is a lack of solid evidence on how metabolism and proliferation are connected in pancreatic carcinogenesis.

CONCLUSION

Understanding early and subtle changes in cellular metabolism of pancreatic epithelial-and specifically of acinar-cells, which accompany or directly influence malignant transformation and uncontrolled proliferation, will be paramount to define novel imaging and other modalities for earlier detection of PDAC.

Understanding metastasis in pancreatic cancer: a call for new clinical approaches

Although metastasis is a major cause of morbidity and mortality in patients with pancreatic cancer, the requisite events are currently unknown. In this issue of Cell, Haeno et al. and Rhim et al. propose that metastasis occurs much earlier than previously anticipated, with clear implications for improving patient care.

Computational modeling of pancreatic cancer reveals kinetics of metastasis suggesting optimum treatment strategies

Pancreatic cancer is a leading cause of cancer-related death, largely due to metastatic dissemination. We investigated pancreatic cancer progression by utilizing a mathematical framework of metastasis formation together with comprehensive data of 228 patients, 101 of whom had autopsies. We found that pancreatic cancer growth is initially exponential. After estimating the rates of pancreatic cancer growth and dissemination, we determined that patients likely harbor metastases at diagnosis and predicted the number and size distribution of metastases as well as patient survival. These findings were validated in an independent database. Finally, we analyzed the effects of different treatment modalities, finding that therapies that efficiently reduce the growth rate of cells earlier in the course of treatment appear to be superior to upfront tumor resection. These predictions can be validated in the clinic. Our interdisciplinary approach provides insights into the dynamics of pancreatic cancer metastasis and identifies optimum therapeutic interventions.

Computational modeling of pancreatic cancer reveals kinetics of metastasis suggesting optimum treatment strategies

Pancreatic cancer is a leading cause of cancer-related death, largely due to metastatic dissemination. We investigated pancreatic cancer progression by utilizing a mathematical framework of metastasis formation together with comprehensive data of 228 patients, 101 of whom had autopsies. We found that pancreatic cancer growth is initially exponential. After estimating the rates of pancreatic cancer growth and dissemination, we determined that patients likely harbor metastases at diagnosis and predicted the number and size distribution of metastases as well as patient survival. These findings were validated in an independent database. Finally, we analyzed the effects of different treatment modalities, finding that therapies that efficiently reduce the growth rate of cells earlier in the course of treatment appear to be superior to upfront tumor resection. These predictions can be validated in the clinic. Our interdisciplinary approach provides insights into the dynamics of pancreatic cancer metastasis and identifies optimum therapeutic interventions.

Small cell and large cell neuroendocrine carcinomas of the pancreas are genetically similar and distinct from well-differentiated pancreatic neuroendocrine tumors

Poorly differentiated neuroendocrine carcinomas (NECs) of the pancreas are rare malignant neoplasms with a poor prognosis. The aim of this study was to determine the clinicopathologic and genetic features of poorly differentiated NECs and compare them with other types of pancreatic neoplasms. We investigated alterations of KRAS, CDKN2A/p16, TP53, SMAD4/DPC4, DAXX, ATRX, PTEN, Bcl2, and RB1 by immunohistochemistry and/or targeted exomic sequencing in surgically resected specimens of 9 small cell NECs, 10 large cell NECs, and 11 well-differentiated neuroendocrine tumors (PanNETs) of the pancreas. Abnormal immunolabeling patterns of p53 and Rb were frequent (p53, 18 of 19, 95%; Rb, 14 of 19, 74%) in both small cell and large cell NECs, whereas Smad4/Dpc4, DAXX, and ATRX labeling was intact in virtually all of these same carcinomas. Abnormal immunolabeling of p53 and Rb proteins correlated with intragenic mutations in the TP53 and RB1 genes. In contrast, DAXX and ATRX labeling was lost in 45% of PanNETs, whereas p53 and Rb immunolabeling was intact in these same cases. Overexpression of Bcl-2 protein was observed in all 9 small cell NECs (100%) and in 5 of 10 (50%) large cell NECs compared with only 2 of 11 (18%) PanNETs. Bcl-2 overexpression was significantly correlated with higher mitotic rate and Ki67 labeling index in neoplasms in which it was present. Small cell NECs are genetically similar to large cell NECs, and these genetic changes are distinct from those reported in PanNETs. The finding of Bcl-2 overexpression in poorly differentiated NECs, particularly small cell NEC, suggests that Bcl-2 antagonists/inhibitors may be a viable treatment option for these patients.

Two sides of the story? Smad4 loss in pancreatic cancer versus head-and-neck cancer

TGFβ signaling Smads (Smad2, 3, and 4) were suspected tumor suppressors soon after their discovery. Nearly two decades of research confirmed this role and revealed other divergent and cancer-specific functions including paradoxical tumor promotion effects. Although Smad4 is the most potent tumor suppressor, its functions are highly context-specific as exemplified by pancreatic cancer and head-and-neck cancer: in pancreatic cancer, Smad4 loss cannot initiate tumor formation but promotes metastases while in head-and-neck cancer Smad4 loss promotes cancer progression but also initiates tumor formation, likely through effects on genomic instability. The differing consequences of impaired Smad signaling in human cancers and the molecular mechanisms that underpin these differences will have important implications for the design and application of novel targeted therapies.

Perineural invasion and lymph node involvement as indicators of surgical outcome and pattern of recurrence in the setting of preoperative gemcitabine-based chemoradiation therapy for resectable pancreatic cancer

OBJECTIVE

To analyze the histopathological indicators significantly associated with surgical outcome and the pattern of recurrence in the setting of preoperative gemcitabine-based chemoradiation therapy (CRT) and subsequent pancreatectomy.

BACKGROUND

Clinicopathological assessment of the resected specimen is an indispensable tool for predicting patient prognosis and localizing high-risk sites for tumor relapse. This procedure is also essential for the establishment of efficient postoperative follow-up protocols in the setting of a preoperative CRT strategy.

METHODS

In a prospective phase II clinical trial at our hospital, 110 patients received preoperative CRT and subsequent resection. All 110 resected cases were included in this study. We employed disease-free survival (DFS) as a surgical outcome, and the pattern of recurrence was divided into 2 categories: (1) recurrence in the abdominal cavity (RAC), defined as either a locoregional or a peritoneal recurrence; or (2) distant recurrence (DR), defined as cancer recurrence in a distant organ. Clinicopathological variables were analyzed in association with DFS, RAC, and DR.

RESULTS

Positive nodal involvement and perineural invasion were independent factors that were significantly associated with an unfavorable DFS (P = 0.021 and P = 0.026, respectively). The presence of perineural invasion was the single independent variable significantly associated with an increased risk of RAC (P = 0.002), whereas the status of nodal involvement was the single independent variable significantly associated with an increased risk of DR (P = 0.013).

CONCLUSIONS

The status of nodal involvement and perineural invasion in resected specimens are significantly associated with DFS and clearly predict the pattern of recurrence in the setting of a preoperative gemcitabine-based CRT strategy. This study is registered at UMIN-CTR and carries the ID number UMIN000001804.

EUS or percutaneously guided intratumoral TNFerade biologic with 5-fluorouracil and radiotherapy for first-line treatment of locally advanced pancreatic cancer: a phase I/II study

BACKGROUND

TNFeradeBiologic (AdGVEGR.TNF.11D) is a replication-deficient adenoviral vector that expresses tumor necrosis factor-α (TNF-α) under the control of the Egr-1 promoter, which is inducible by chemotherapy and radiation.

OBJECTIVE

This study was conducted to determine the maximal tolerated dose of TNFeradeBiologic with standard chemoradiotherapy and preliminary activity and safety of the combination in the treatment of locally advanced pancreatic cancer (LAPC).

DESIGN

TNFeradeBiologic was injected into locally advanced pancreatic carcinomas by using EUS or percutaneous administration once a week for 5 weeks together with 50.4 Gy radiation and 5-fluorouracil (5-FU) 200 mg/m(2) daily over 5.5 weeks. Dose levels from 4 × 10(9) to 1 × 10(12) particle units (PU) were studied.

SETTING

Multicentered, academic institutions.

PATIENTS

Fifty patients with LAPC were treated.

INTERVENTIONS

Doses of TNFerade Biologic were administered to patients.

MAIN OUTCOME MEASUREMENTS

Toleration of TNFerade Biologic was measured through toxicity and tumor response, by using the criteria of the Response Evaluation Criteria in Solid Tumors and the World Health Organization, and was reviewed by a central radiology facility. Overall survival and progression-free survival were also measured.

RESULTS

Dose-limiting toxicities of pancreatitis and cholangitis were observed in 3 patients at the 1 × 10(12) PU dose, making 4 × 10(11) PU the maximum tolerated dose. One complete response, 3 partial responses, and 12 patients with stable disease were noted. Seven patients eventually went to surgery, 6 had clear margins, and 3 survived >24 months.

LIMITATIONS

This is a Phase 1/2 non-randomized study.

CONCLUSIONS

Intratumoral delivery of TNFerade Biologic by EUS with fine-needle viral injection or percutaneously, combined with chemoradiation, shows promise in the treatment of LAPC. There appeared to be better clinical outcome at the maximal tolerated dose than at lower doses. The dose of 4 ×10(11) PU TNFerade Biologic was generally well tolerated, with encouraging indications of activity, and will be tested in the randomized phase of this study. Delivery of TNFerade Biologic did not interfere with subsequent surgical resection.

Failure to adhere to protocol specified radiation therapy guidelines was associated with decreased survival in RTOG 9704--a phase III trial of adjuvant chemotherapy and chemoradiotherapy for patients with resected adenocarcinoma of the pancreas

PURPOSE

In Radiation Therapy Oncology Group 9704, as previously published, patients with resected pancreatic adenocarcinoma received continuous infusion 5-FU and concurrent radiotherapy (5FU-RT). 5FU-RT treatment was preceded and followed by randomly assigned chemotherapy, either 5-FU or gemcitabine. This analysis explored whether failure to adhere to specified RT guidelines influenced survival and/or toxicity.

METHODS AND MATERIALS

RT requirements were protocol specified. Adherence was scored as per protocol (PP) or less than per protocol (

RESULTS

RT was scored for 416 patients: 216 PP and 200

CONCLUSIONS

This is the first Phase III, multicenter, adjuvant protocol for pancreatic adenocarcinoma to evaluate the impact of adherence to specified RT protocol guidelines on protocol outcomes. Failure to adhere to specified RT guidelines was associated with reduced survival and, for patients receiving gemcitabine, trend toward increased nonhematologic toxicity.

Collapse

Key Words

• radiotherapy
• quality assurance
• pancreatic adenocarcinoma
• adjuvant therapy
• chemoradiotherapy

Collapse

MESH Headings

• Adenocarcinoma/mortality
• Adenocarcinoma/pathology
• Adenocarcinoma/therapy
• Adult
• Aged
• Aged, 80 and over
• Antimetabolites, Antineoplastic/therapeutic use
• Chemoradiotherapy/adverse effects
• Chemoradiotherapy/methods
• Chemotherapy, Adjuvant/adverse effects
• Deoxycytidine/adverse effects
• Deoxycytidine/analogs & derivatives
• Deoxycytidine/therapeutic use
• Female
• Fluorouracil/adverse effects
• Fluorouracil/therapeutic use
• Guideline Adherence
• Humans
• Male
• Middle Aged
• Multivariate Analysis
• Pancreatic Neoplasms/mortality
• Pancreatic Neoplasms/pathology
• Pancreatic Neoplasms/therapy
• Survival Analysis
• Gemcitabine

Collapse

Grants

• UL1 RR025741 NCRR NIH HHS
• CA21661 NCI NIH HHS
• U10 CA021661 NCI NIH HHS
• U10 CA037422 NCI NIH HHS
• CA37422 NCI NIH HHS

Collapse

Affiliation(s)

Ross A. Abrams Rush University Medical Center, Chicago, IL
Kathryn A. Winter Radiation Therapy Oncology Group Statistical Center, Philadelphia, PA
William F. Regine University of Maryland, Baltimore, MD
Howard Safran Brown University, Providence, RI
John P. Hoffman Fox Chase Cancer Center, Philadelphia, PA
Robert Lustig Radiation Therapy Oncology Group Statistical Center, Philadelphia, PA
Andre A. Konski Wayne State Medical Center, Detroit, MI
Al B. Benson Northwestern University, Chicago, IL
John S. Macdonald St. Vincent's Cancer Care Center, New York, NY
Tyvin A. Rich University of Virginia, Charlottesville, VA
Christopher G. Willett Duke University, Durham, NC

Collapse

Collaborators Collapse

A novel survival-based tissue microarray of pancreatic cancer validates MUC1 and mesothelin as biomarkers

BACKGROUND

One-fifth of patients with seemingly 'curable' pancreatic ductal adenocarcinoma (PDA) experience an early recurrence and death, receiving no definable benefit from a major operation. Some patients with advanced stage tumors are deemed 'unresectable' by conventional staging criteria (e.g. liver metastasis), yet progress slowly. Effective biomarkers that stratify PDA based on biologic behavior are needed. To help researchers sort through the maze of biomarker data, a compendium of ∼2500 published candidate biomarkers in PDA was compiled (PLoS Med, 2009. 6(4) p. e1000046).

METHODS AND FINDINGS

Building on this compendium, we constructed a survival tissue microarray (termed s-TMA) comprised of short-term (cancer-specific death <12 months, n = 58) and long-term survivors (>30 months, n = 79) who underwent resection for PDA (total, n = 137). The s-TMA functions as a biological filter to identify bona fide prognostic markers associated with survival group extremes (at least 18 months separate survival groups). Based on a stringent selection process, 13 putative PDA biomarkers were identified from the public biomarker repository. Candidates were tested against the s-TMA by immunohistochemistry to identify the best markers of tumor biology. In a multivariate model, MUC1 (odds ratio, OR = 28.95, 3+ vs. negative expression, p = 0.004) and MSLN (OR = 12.47, 3+ vs. negative expression, p = 0.01) were highly predictive of early cancer-specific death. By comparison, pathologic factors (size, lymph node metastases, resection margin status, and grade) had ORs below three, and none reached statistical significance. ROC curves were used to compare the four pathologic prognostic features (ROC area = 0.70) to three univariate molecular predictors (MUC1, MSLN, MUC2) of survival group (ROC area = 0.80, p = 0.07).

CONCLUSIONS

MUC1 and MSLN were superior to pathologic features and other putative biomarkers as predicting survival group. Molecular assays comparing cancers from short and long survivors are an effective strategy to screen biomarkers and prioritize candidate cancer genes for diagnostic and therapeutic studies.

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.

Effect of neoadjuvant chemoradiation and surgical technique on recurrence of localized pancreatic cancer

OBJECTIVES

To determine the influence of neoadjuvant chemoradiation and standardized dissection of the superior mesenteric artery upon the oncologic outcome of patients with localized pancreatic adenocarcinoma.

METHODS

One hundred ninety-four patients with pancreatic adenocarcinoma who underwent pancreaticoduodenectomy between 2004 and 2008 were evaluated. The retroperitoneal dissection was performed directly along the superior mesenteric artery in all cases. A standard histopathologic protocol that measured the "superior mesenteric artery (SMA) margin distance" between cancer cells and the superior mesenteric artery was employed.

RESULTS

Seventy-six percent of patients received neoadjuvant chemoradiation. The SMA margin was positive in 4% of patients but an additional 22% of patients with a negative margin had a SMA margin distance of ≤1 mm. Preoperative CT images overestimated the SMA margin distance in 73% of cases. Patients who received chemoradiation had longer SMA margin distances than those who did not. Patients who received chemoradiation and had a SMA margin of >1 mm had the lowest recurrence rates. Administration of neoadjuvant chemoradiation and lower estimated blood loss were independently associated with longer progression-free survival on multivariate analysis.

CONCLUSIONS

Preoperative chemoradiation and meticulous dissection of the superior mesenteric artery maximize the distance between cancer cells and the SMA margin and may influence locoregional control.