Phase 2 study of erlotinib combined with adjuvant chemoradiation and chemotherapy in patients with resectable pancreatic cancer. Int J Radiat Oncol Biol Phys. 2013;86:678-685. [PMID: 23773391 DOI: 10.1016/j.ijrobp.2013.03.032]

Insulin receptor substrate 1 is a novel member of EGFR signaling in pancreatic cells

Pancreatic ductal adenocarcinoma is an extremely incurable cancer type characterized by cells with highly proliferative capacity and resistance against the current therapeutic options. Our study reveals that IRS1 acts as a bridging molecule between EGFR and IGFR/InsR signalization providing a potential mechanism for the interplay between signaling pathways and bypassing EGFR-targeted or IGFR/InsR-targeted therapies. The analysis of IRS1 phosphorylation status in four pancreatic cell lines identified the impact of EGFR signaling on IRS1 activation in comparison with InsR/IGFR signaling. Significantly reduced viability was observed in IRS1-silenced cells even upon EGF stimulation showing the critical role of IRS1 in the EGFR signaling network in both malignant and normal pancreatic cells. This study also demonstrated that EGFR binds directly to IRS1 and at least on two tyrosine sites, Y612 and Y896, IRS1 becomes phosphorylated in response to EGF stimulation. Mechanistically, the EGFR-mediated phosphorylation of IRS1 can further activate the MAPK signaling pathway with the recruitment of GRB2 protein. Collectively, in this study, IRS1 was identified as a crucial regulator in the EGFR signaling suggesting IRS1 as a potential target for more durable responses to targeted PDAC therapy.

Erlotinib combination with a mitochondria-targeted ubiquinone effectively suppresses pancreatic cancer cell survival

BACKGROUND

Pancreatic cancer is a leading cause of cancer-related deaths. Increased activity of the epidermal growth factor receptor (EGFR) is often observed in pancreatic cancer, and the small molecule EGFR inhibitor erlotinib has been approved for pancreatic cancer therapy by the food and drug administration. Nevertheless, erlotinib alone is ineffective and should be combined with other drugs to improve therapeutic outcomes. We previously showed that certain receptor tyrosine kinase inhibitors can increase mitochondrial membrane potential (Δψm), facilitate tumor cell uptake of Δψm-sensitive agents, disrupt mitochondrial homeostasis, and subsequently trigger tumor cell death. Erlotinib has not been tested for this effect.

AIM

To determine whether erlotinib can elevate Δψm and increase tumor cell uptake of Δψm-sensitive agents, subsequently triggering tumor cell death.

METHODS

Δψm-sensitive fluorescent dye was used to determine how erlotinib affects Δψm in pancreatic adenocarcinoma (PDAC) cell lines. The viability of conventional and patient-derived primary PDAC cell lines in 2D- and 3D cultures was measured after treating cells sequentially with erlotinib and mitochondria-targeted ubiquinone (MitoQ), a Δψm-sensitive MitoQ. The synergy between erlotinib and MitoQ was then analyzed using SynergyFinder 2.0. The preclinical efficacy of the two-drug combination was determined using immune-compromised nude mice bearing PDAC cell line xenografts.

RESULTS

Erlotinib elevated Δψm in PDAC cells, facilitating tumor cell uptake and mitochondrial enrichment of Δψm-sensitive agents. MitoQ triggered caspase-dependent apoptosis in PDAC cells in culture if used at high doses, while erlotinib pretreatment potentiated low doses of MitoQ. SynergyFinder suggested that these drugs synergistically induced tumor cell lethality. Consistent with in vitro data, erlotinib and MitoQ combination suppressed human PDAC cell line xenografts in mice more effectively than single treatments of each agent.

CONCLUSION

Our findings suggest that a combination of erlotinib and MitoQ has the potential to suppress pancreatic tumor cell viability effectively.

Neoadjuvant and Adjuvant Treatments for Resectable and Borderline Resectable Pancreatic Ductal Adenocarcinoma: The Current Status of Pancreatic Ductal Adenocarcinoma Treatment in Japan

Resection is the only curative treatment for pancreatic ductal adenocarcinoma (PDAC). Although the outcome of technically resectable PDAC has improved with advances in surgery and adjuvant therapy, the 5-year survival rate remains low at 20% to 40%. More effective therapy is needed. Almost 15 years ago, the National Comprehensive Cancer Network guidelines proposed a resectability classification of PDAC based on preoperative imaging. Since then, treatment strategies for PDAC have been devised based on resectability. The standard of care for resectable PDAC is adjuvant chemotherapy after R0 resection, as shown by the results of pivotal clinical trials. With regard to neoadjuvant treatment, several recent clinical trials comparing neoadjuvant treatment with upfront resection have been conducted on resectable PDAC and borderline resectable PDAC, and the benefits and efficacy of neoadjuvant treatment for pancreatic cancer has become clearer. The significance of neoadjuvant treatment for resectable PDAC remains controversial, but in borderline resectable PDAC the efficacy of neoadjuvant treatment has been further recognised, although the standard of care has not yet been established. Several promising clinical trials for PDAC are ongoing. This review presents previous and ongoing trials of perioperative treatment for resectable and borderline resectable PDAC, focusing on the difference between Asian and Western countries.

Tumour microenvironment and heterotypic interactions in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDA) is a disease with a survival rate of 9%; this is due to its chemoresistance and the large tumour stroma that occupies most of the tumour mass. It is composed of a large number of cells of the immune system, such as Treg cells, tumour-associated macrophages (TAMs), myeloid suppressor cells (MDCs) and tumour-associated neutrophiles (TANs) that generate an immunosuppressive environment by the release of inflammatory cytokines. Moreover, cancer-associated fibroblast (CAFs) provide a protective coverage that would difficult the access of chemotherapy to the tumour. According to this, new therapies that could remodel this heterogeneous tumour microenvironment, such as adoptive T cell therapies (ACT), immune checkpoint inhibitors (ICI), and CD40 agonists, should be developed for targeting PDA. This review organizes the different cell populations found in the tumour stroma involved in tumour progression in addition to the different therapies that are being studied to counteract the tumour.

Future challenges in gastroenterology and hepatology, between innovations and unmet needs: A SIGE Young Editorial Board's perspective

Gastroenterology, Digestive Endoscopy and Hepatology have faced significant improvements in terms of diagnosis and therapy in the last decades. However, many fields still remain poorly explored, and many questions unanswered. Moreover, basic-science, as well as translational and clinical discoveries, together with technology advancement will determine further steps toward a better, refined care for many gastroenterological disorders in the future. Therefore, the Young Investigators of the Italian Society of Gastroenterology (SIGE) joined together, offering a perspective on major future innovations in some hot clinical topics in Gastroenterology, Endoscopy, and Hepatology, as well as the current pitfalls and the grey zones.

Clinical and Preclinical Outcomes of Combining Targeted Therapy With Radiotherapy

In the era of precision medicine, radiation medicine is currently focused on the precise delivery of highly conformal radiation treatments. However, the tremendous developments in targeted therapy are yet to fulfill their full promise and arguably have the potential to dramatically enhance the radiation therapeutic ratio. The increased ability to molecularly profile tumors both at diagnosis and at relapse and the co-incident progress in the field of radiogenomics could potentially pave the way for a more personalized approach to radiation treatment in contrast to the current ‘‘one size fits all’’ paradigm. Few clinical trials to date have shown an improved clinical outcome when combining targeted agents with radiation therapy, however, most have failed to show benefit, which is arguably due to limited preclinical data. Several key molecular pathways could theoretically enhance therapeutic effect of radiation when rationally targeted either by directly enhancing tumor cell kill or indirectly through the abscopal effect of radiation when combined with novel immunotherapies. The timing of combining molecular targeted therapy with radiation is also important to determine and could greatly affect the outcome depending on which pathway is being inhibited.

The past, present, and future status of multimodality treatment for resectable/borderline resectable pancreatic ductal adenocarcinoma

A multimodal approach to treating pancreatic ductal adenocarcinoma (PDAC) is now widely accepted. Improvements in radiological assessment have enabled us to define resectability in detail. Multimodality treatment is essential for patients, especially for those with PDAC in the borderline resectable (BR) stage. Even for disease in a resectable (R) stage, adjuvant and neoadjuvant therapies have demonstrated beneficial outcomes in several trials and analyses. Thus, there is growing interest in optimization of the perioperative therapeutic strategy. We discuss the transition of resectability criteria and the global standard of adjuvant and neoadjuvant treatments for patients with R/BR-PDAC.

EGFR, but not COX-2, protein in resected pancreatic ductal adenocarcinoma is associated with poor survival

The effects of EGFR and COX-2 protein overexpression on clinical outcomes in pancreatic ductal adenocarcinoma (PDAC) patients remains unclear. Therefore, the aim of the present study was to evaluate the protein expression of epithelial growth factor receptor (EGFR) and cyclooxygenase-2 (COX-2) in tumor cells in surgically resected PDAC, in comparison with clinicopathological characteristics and clinical outcomes. Immunohistochemical staining of formalin-fixed paraffin-embedded tissue derived from surgically resected tumors was performed. Tissue slides were evaluated for membrane wild-type EGFR and cytoplasmic COX-2 staining using a histoscore system. Statistical associations between EGFR and COX-2 staining and clinicopathological characteristics were examined to predict survival. In a cohort of 32 resected PDAC patients, high EGFR protein expression in tumor cells was significantly associated with shorter median overall survival (7.9 vs. 39.2 months, P=0.0038). The corresponding hazard ratio (HR) for patients with high EGFR protein expression in tumor cells was 3.12 [95% confidence interval (CI): 1.39–7.00, P=0.006]. COX-2 protein expression was not associated with survival (22.6 vs. 24.5 months P=0.60; HR 1.22 95% CI: 0.59–2.51, P=0.60). Following multivariate Cox regression analysis, high EGFR protein expression in tumor cells (P=0.043) remained as significant independent prognostic factor for survival. In conclusion, high wild-type EGFR protein expression, but not COX-2 protein expression, in tumor cells is a prognostic factor for reduced overall survival following pancreatic tumor resection, supporting a role for EGFR in identifying resected patients that may benefit from EGFR-targeted therapy.

Combination of novel systemic agents and radiotherapy for solid tumors - Part II: An AIRO (Italian association of radiotherapy and clinical oncology) overview focused on treatment toxicity

Clinical development and use of novel systemic agents in combination with radiotherapy (RT) is at nowadays most advanced in the field of treatment of solid tumors. Although for many of these substances preclinical studies provide sufficient evidences on their principal capability to enhance radiation effects, the majority of them have not been investigated in even phase I clinical trials for safety in the context of RT. In clinical practice, unexpected acute and late side effects may emerge especially in combination with RT. As a matter of fact, despite combined modality treatment holds potential for enhancing the therapeutic ratio, some concerns are raised from the lack of high-quality clinical data to guide the care of patients who are treated with novel compounds in conjunction with RT. The aim of this review is to provide, from a radio-oncological point of view, an overview of the most advanced combined treatment concepts for solid tumors focusing on treatment toxicity.

Combination of novel systemic agents and radiotherapy for solid tumors - part I: An AIRO (Italian association of radiotherapy and clinical oncology) overview focused on treatment efficacy

Over the past century, technologic advances have promoted the evolution of radiation therapy into a precise treatment modality allowing for the maximal administration of dose to tumors while sparing normal tissues. In parallel with this technological maturation, the rapid expansion in understanding the basic biology and heterogeneity of cancer has led to the development of several compounds that target specific pathways. Many of them are in advanced steps of clinical development for combination treatments with radiotherapy, and can be incorporated into radiation oncology practice for a personalized approach to maximize the therapeutic gain. This review describes the rationale for combining novel agents with radiation, and provides an overview of the current landscape focused on treatment efficacy.

Smad4 Loss Correlates With Higher Rates of Local and Distant Failure in Pancreatic Adenocarcinoma Patients Receiving Adjuvant Chemoradiation

OBJECTIVES

The tumor suppressor gene SMAD4 (DPC4) is genetically inactivated in approximately half of pancreatic ductal adenocarcinomas (PDAs). We examined whether Smad4 tumor status was associated with outcomes after adjuvant chemoradiation (CRT) for resected PDAs.

METHODS

Patients treated with adjuvant CRT were identified (N = 145). Smad4 status was determined by immunolabeling and graded as intact or lost. Kaplan-Meier method and multivariable competing risk analyses were performed.

RESULTS

On multivariate competing risk analysis, Smad4 loss was associated with increased risk of local recurrence (LR) (hazard ratio, 2.37; 95% confidence interval, 1.10-5.11; P = 0.027), distant failure (DF) (hazard ratio, 1.71; 95% confidence interval, 1.03-2.83; P = 0.037), and synchronous LR and DF at first recurrence (14.9 % vs 5.3%, P = 0.07) compared with Smad4 intact cancers. Smad4 loss was not associated with median overall survival (22 vs 22 months; P = 0.63) or disease-free survival (lost [13.6 months] vs intact [13.5 months], P = 0.79).

CONCLUSIONS

After PDA resection and adjuvant CRT, Smad4 loss correlated with higher risk of LR and DF, but not with survival. Smad4 loss may help predict which surgical patients are at higher risk for failure after definitive management and may benefit from intensified adjuvant therapy.

Successes and Failures of Combined Modalities in Upper Gastrointestinal Malignancies: New Directions

Upper gastrointestinal malignancies generally have moderate to poor cure rates, even in the earliest stages, thereby implying that both local and systemic treatments have room for improvement. Therapeutic options are broadening, however, with the development of new immunotherapies and targeted agents, which can have synergistic effects with radiotherapy. Here we discuss the current state of combined modality therapy for upper gastrointestinal malignancies, specifically recent successes and setbacks in trials of radiation therapy with targeted therapies, vaccines, immunotherapies, and chemotherapies.

Neoadjuvant therapy versus upfront surgical strategies in resectable pancreatic cancer: A Markov decision analysis

BACKGROUND

Neoadjuvant therapy is gaining acceptance as a valid treatment option for borderline resectable pancreatic cancer; however, its value for clearly resectable pancreatic cancer remains controversial. The aim of this study was to use a Markov decision analysis model, in the absence of adequately powered randomized trials, to compare the life expectancy (LE) and quality-adjusted life expectancy (QALE) of neoadjuvant therapy to conventional upfront surgical strategies in resectable pancreatic cancer patients.

METHODS

A Markov decision model was created to compare two strategies: attempted pancreatic resection followed by adjuvant chemoradiotherapy and neoadjuvant chemoradiotherapy followed by restaging with, if appropriate, attempted pancreatic resection. Data obtained through a comprehensive systematic search in PUBMED of the literature from 2000 to 2015 were used to estimate the probabilities used in the model. Deterministic and probabilistic sensitivity analyses were performed.

RESULTS

Of the 786 potentially eligible studies identified, 22 studies met the inclusion criteria and were used to extract the probabilities used in the model. Base case analyses of the model showed a higher LE (32.2 vs. 26.7 months) and QALE (25.5 vs. 20.8 quality-adjusted life months) for patients in the neoadjuvant therapy arm compared to upfront surgery. Probabilistic sensitivity analyses for LE and QALE revealed that neoadjuvant therapy is favorable in 59% and 60% of the cases respectively.

CONCLUSION(S)

Although conceptual, these data suggest that neoadjuvant therapy offers substantial benefit in LE and QALE for resectable pancreatic cancer patients. These findings highlight the value of further prospective randomized trials comparing neoadjuvant therapy to conventional upfront surgical strategies.

Phase I Trial of Consolidative Radiotherapy with Concurrent Bevacizumab, Erlotinib and Capecitabine for Unresectable Pancreatic Cancer

Purpose

To determine the safety, tolerability and maximum tolerated dose (MTD) of addition of erlotinib to bevacizumab and capecitabine-based definitive chemoradiation (CRT) in unresectable pancreatic cancer.

Methods

Seventeen patients with CT-staged, biopsy-proven unresectable pancreatic cancer were enrolled between 3/2008 and 10/2010. Prior chemotherapy was permitted. Two patients each were enrolled at dose levels (DLs) 1–4 and 9 patients at DL 5. All patients received 50.4 Gy (GTV only) in 28 fractions with concurrent capecitabine, bevacizumab and erlotinib. Dose of each drug was escalated in 5 DLs using the continual reassessment method. Bevacizumab was escalated from 5mg/Kg q2weeks (DLs 1–4) to 10mg/Kg q2weeks (DL 5); daily erlotinib from 100mg/day (DLs 1–2) to 150 mg/Kg (DLs 3–5); and capecitabine from 400mg/m² twice daily on days of radiation (DL 1) to 650mg/m² (DLs 2–3) to 825 mg/m² (DLs 4–5). Reassessment for potential resection was performed 6–8 weeks later.

Results

Sixteen patients received gemcitabine-based chemotherapy prior to CRT. With a median clinical follow-up of 10 months, no grade 3 toxicities were observed in DLs 1–4. Three (33%) patients at DL 5 developed a grade 3 acute toxicity (2 diarrhea, 1 rash). No grade 4 or 5 toxicities were seen. DL 4 was selected as the MTD; therefore, the recommended doses in combination with radiation are: bevacizumab, 5mg/Kg q2weeks; erlotinib, 150 mg/Kg daily; and capecitabine, 825mg/m² BID. Median survival was 17.4 months. Of the five patients who underwent resection, 4 were originally deemed locally advanced and 1 was borderline resectable. Three patients had excellent pathological response (2 complete response and 20% viable tumor) at surgery, and the 2 patients with complete response are still alive at 61 and 67 months of follow up with no local or distant failures.

Conclusions

This chemoradiation regimen at the recommended dose levels is safe and tolerable for patients with unresectable pancreatic cancer and merits further evaluation.

Recent Advances and Prospects for Multimodality Therapy in Pancreatic Cancer

The outcomes for treatment of pancreatic cancer have not improved dramatically in many decades. However, the recent promising results with combination chemotherapy regimens for metastatic disease increase optimism for future treatments. With greater control of overt or occult metastatic disease, there will likely be an expanding role for local treatment modalities, especially given that nearly a third of pancreatic cancer patients have locally destructive disease without distant metastatic disease at the time of death. Technical advances have allowed for the safe delivery of dose-escalated radiation therapy, which can then be combined with chemotherapy, targeted agents, immunotherapy, and nanoparticulate drug delivery techniques to produce novel and improved synergistic effects. Here we discuss recent advances and future directions for multimodality therapy in pancreatic cancer.

Identification of Poor-outcome Biliopancreatic Carcinoma Patients With Two-marker Signature Based on ATF6α and p-p38 "STARD Compliant"

Biliopancreatic cancer is one of the most aggressive solid neoplasms, and incidence is rising worldwide. It is known that ATF6α is one of the transmembrane proteins that acts crucially in endoplasmic reticulum stress response, and knockdown induces apoptosis of pancreatic cells. Apart from this, p-p38 has been previously correlated with better outcome in pancreatic cancer. Interestingly, ATF6α knockdown pancreatic cells showed increased p-p38. The aim of this study was to evaluate the expression of these 2 proteins, p-p38 and ATF6α, and their correlation with the outcome of biliopancreatic adenocarcinoma patients. Samples from patients with biliopancreatic adenocarcinoma that underwent pancreaticoduodenectomy from 2007 to 2013 were used to construct a tissue microarray to evaluate p-p38 and ATF6α proteins by immunohistochemistry. We observed that both markers showed a tendency to impact in the time to recurrence; then a combination of these 2 proteins was analyzed. Combination of ATF6α(high) and p-p38(low) was strongly associated with a higher risk of recurrence (hazard ratio 2.918, P = 0.013). This 2-protein model remained significant after multivariate adjustment.We proposed a 2-protein signature based on ATF6α(high) and p-p38(low) as a potential biomarker of risk of recurrence in resected biliopancreatic adenocarcinoma patients.

Molecular Targeted Intervention for Pancreatic Cancer

Pancreatic cancer (PC) remains one of the worst cancers, with almost uniform lethality. PC risk is associated with westernized diet, tobacco, alcohol, obesity, chronic pancreatitis, and family history of pancreatic cancer. New targeted agents and the use of various therapeutic combinations have yet to provide adequate treatments for patients with advanced cancer. To design better preventive and/or treatment strategies against PC, knowledge of PC pathogenesis at the molecular level is vital. With the advent of genetically modified animals, significant advances have been made in understanding the molecular biology and pathogenesis of PC. Currently, several clinical trials and preclinical evaluations are underway to investigate novel agents that target signaling defects in PC. An important consideration in evaluating novel drugs is determining whether an agent can reach the target in concentrations effective to treat the disease. Recently, we have reported evidence for chemoprevention of PC. Here, we provide a comprehensive review of current updates on molecularly targeted interventions, as well as dietary, phytochemical, immunoregulatory, and microenvironment-based approaches for the development of novel therapeutic and preventive regimens. Special attention is given to prevention and treatment in preclinical genetically engineered mouse studies and human clinical studies.

New targeted therapies in pancreatic cancer

Patients with pancreatic cancer have a poor prognosis with a median survival of 4-6 mo and a 5-year survival of less than 5%. Despite therapy with gemcitabine, patient survival does not exceed 6 mo, likely due to natural resistance to gemcitabine. Therefore, it is hoped that more favorable results can be obtained by using guided immunotherapy against molecular targets. This review summarizes the new leading targeted therapies in pancreatic cancers, focusing on passive and specific immunotherapies. Passive immunotherapy may have a role for treatment in combination with radiochemotherapy, which otherwise destroys the immune system along with tumor cells. It includes mainly therapies targeting against kinases, including epidermal growth factor receptor, Ras/Raf/mitogen-activated protein kinase cascade, human epidermal growth factor receptor 2, insulin growth factor-1 receptor, phosphoinositide 3-kinase/Akt/mTOR and hepatocyte growth factor receptor. Therapies against DNA repair genes, histone deacetylases, microRNA, and pancreatic tumor tissue stromal elements (stromal extracellular matric and stromal pathways) are also discussed. Specific immunotherapies, such as vaccines (whole cell recombinant, peptide, and dendritic cell vaccines), adoptive cell therapy and immunotherapy targeting tumor stem cells, have the role of activating antitumor immune responses. In the future, treatments will likely include personalized medicine, tailored for numerous molecular therapeutic targets of multiple pathogenetic pathways.

Growth inhibition and apoptosis induction by alternol in pancreatic carcinoma cells

AIM: To investigate the effect of alternol on pancreatic cancer cells.

METHODS: Pancreatic cancer cells PANC-1 and BxPC3 were treated with various concentrations of alternol for 24, 48 and 72 h. Cell proliferation was measured by cell counting. Cell cycle distribution and mitochondrial membrane potential were determined by flow cytometry. Apoptosis was determined by a TdT-mediated dUTP nick end labeling assay and Hoechst staining. Expression of caspase 3, Bcl-2, p53 and p21 was measured by western blotting.

RESULTS: Alternol showed dose- and time-dependent inhibition of the proliferation of PANC-1 and BxPC3 cells in vitro. Alternol induced apoptosis and cell cycle arrest at S phase and decreased mitochondrial membrane potential. Alternol activated caspase 3, upregulated p53 and p21 expression, and downregulated Bcl-2 expression in a dose-dependent manner.

CONCLUSION: Our results suggested that alternol is a candidate for treatment of pancreatic cancer.

Trial Watch: Radioimmunotherapy for oncological indications

During the past two decades, it has become increasingly clear that the antineoplastic effects of radiation therapy do not simply reflect the ability of X-, β- and γ-rays to damage transformed cells and directly cause their permanent proliferative arrest or demise, but also involve cancer cell-extrinsic mechanisms. Indeed, among other activities, radiotherapy has been shown to favor the establishment of tumor-specific immune responses that operate systemically, underpinning the so-called 'out-of-field' or 'abscopal' effect. Thus, ionizing rays appear to elicit immunogenic cell death, a functionally peculiar variant of apoptosis associated with the emission of a particularly immunostimulatory combination of damage-associated molecular patterns. In line with this notion, radiation therapy fosters, and thus exacerbates, the antineoplastic effects of various treatment modalities, including surgery, chemotherapy and various immunotherapeutic agents. Here, we summarize recent advances in the use of ionizing rays as a means to induce or potentiate therapeutically relevant anticancer immune responses. In addition, we present clinical trials initiated during the past 12 months to test the actual benefit of radioimmunotherapy in cancer patients.

Adjuvant therapy in pancreatic cancer

Pancreatic cancer remains one of the leading causes of cancer related death worldwide with an overall five-year survival of less than 5%. Potentially curative surgery, which alone can improve 5-year survival to 10%, is an option for only 10%-20% of patients at presentation owing to local invasion of the tumour or metastatic disease. Adjuvant chemotherapy has been shown to improve 5-year survival to 20%-25% but conflicting evidence remains with regards to chemoradiation. In this article we review the current evidence available from published randomised trials and discuss ongoing phase III trials in relation to adjuvant therapy in pancreatic cancer.

Adjuvant chemoradiation for pancreatic cancer: what does the evidence tell us?

The role of adjuvant chemoradiation (CRT) for pancreas cancer remains unclear. A handful of randomized trials conducted decades of ago ignited a debate that continues today about whether CRT improves survival after surgery. The many flaws in these trials are well described in the literature, which include the use of antiquated radiation delivery techniques and suboptimal doses. Recent prospective randomized data is lacking, and we eagerly await the results the ongoing Radiation Therapy Oncology Group (RTOG) 0848 trial that is evaluating the utility of high quality adjuvant CRT in resected pancreas cancer patients. Until the results of RTOG 0848 are available we should look to other studies from the modern era to guide adjuvant treatment recommendations. Here we review the current state of the art for adjuvant pancreas CRT with respect to patient selection, radiation techniques, radiation dose, and integration with novel systemic agents.

Radiosensitizers in pancreatic cancer--preclinical and clinical exploits with molecularly targeted agents

There has been an explosion in the number of molecularly targeted agents engineered to inhibit specific molecular pathways driving the tumorigenic phenotype in cancer cells. Some of these molecularly targeted agents have demonstrated robust clinical effects, but few result in meaningful durable responses. Therapeutic radiation is used to treat a majority of cancer patients with recent technologic and pharmacologic enhancements, leading to improvements in the therapeutic ratio for cancer care. Radiotherapy has a very specific role in select cases of postoperative and locally advanced pancreatic cancer patients, but control of metastatic disease still appears to be the major limiting factor behind improvements in cure. Recent rapid autopsy pathologic findings suggest a sub-group of advanced pancreatic cancer patients where death is caused from local disease progression and who would thus benefit from improved local control. One promising approach is to combine molecularly targeted agents with radiotherapy to improve tumor response rates and likelihood of durable local control. We review suggested recommendations on the investigation of molecularly targeted agents as radiosensitizers from preclinical studies to implementation in phase I–II clinical trials. We then discuss a select set of molecularly targeted therapies that we believe show promise as radiosensitizers in the treatment of pancreatic cancer.