Chemoradiation in pancreatic adenocarcinoma: a literature review

Radiotherapy for Locally Advanced Pancreatic Adenocarcinoma-A Critical Review of Randomised Trials

Pancreatic cancer is rising as one of the leading causes of cancer-related death worldwide. Patients often present with advanced disease, limiting curative treatment options and therefore making management of the disease difficult. Systemic chemotherapy has been an established part of the standard treatment in patients with both locally advanced and metastatic pancreatic cancer. In contrast, the use of radiotherapy has no clear defined role in the treatment of these patients. With the evolving imaging and radiation techniques, radiation could become a plausible intervention. In this review, we give an overview over the available data regarding radiotherapy, chemoradiation, and stereotactic body radiation therapy. We performed a systematic search of Embase and the PubMed database, focusing on studies involving locally advanced pancreatic cancer (or non-resectable pancreatic cancer) and radiotherapy without any limitation for the time of publication. We included randomised controlled trials involving patients with locally advanced pancreatic cancer, including radiotherapy, chemoradiation, or stereotactic body radiation therapy. The included articles represented mainly small patient groups and had a high heterogeneity regarding radiation delivery and modality. This review presents conflicting results concerning the addition of radiation and modality in the treatment regimen. Further research is needed to improve outcomes and define the role of radiation therapy in pancreatic cancer.

Advances in stent therapy for malignant biliary obstruction

Malignant biliary obstruction (MBO), result of pancreatobiliary diseases is a challenging condition. Most patients with MBO are inoperable at the time of diagnosis, and the disease is poorly controlled using external-beam radiotherapy and chemotherapy. Biliary stent therapy emerged as a promising strategy for alleviating MBO and prolonging life. However, physicians find it difficult to determine the optimal type of biliary stent for the palliation of MBO. Here, we review the safety and efficacy of available biliary stents, used alone or in combination with brachytherapy, photodynamic therapy and advanced chemotherapeutics, in patients with pancreatobiliary malignancies and put forward countermeasures involving stent obstruction. Furthermore, 3D-printing stents and nanoparticle-loaded stents have broad application prospects for fabricating tailor-made biliary stents.

Gemcitabine-induced haemolytic uraemic syndrome in pancreatic adenocarcinoma

A woman in her mid-70s with metastatic pancreatic adenocarcinoma presented with fatigue, nausea and bilateral leg swelling, 4 days after an intravenous gemcitabine infusion. Additional examination and laboratory tests showed mild hypertension, low haemoglobin, high lactate dehydrogenase, low platelet count and high serum creatinine. The patient was subsequently diagnosed with haemolytic uraemic syndrome (HUS), and gemcitabine administration was immediately ceased. The patient received a 5-day course of methylprednisolone, with a full recovery being made 10 days after diagnosis. Clinicians should be aware of the rare but serious complication of gemcitabine-induced HUS (GiHUS), as early diagnosis and management, which includes prompt discontinuation of gemcitabine, are crucial in promptly resolving this condition. This case report describes one treatment that can be used for the treatment of GiHUS, while briefly covering some other novel treatments that have been described in other studies.

Identification of the Factors Responsible for the Selective in vitro Cytotoxic Activity of Isoprenylated Coumarin Derivatives under Nutrient-deprived Conditions

Pancreatic cancer is one of the most devastating forms of human cancer. The lack of effective clinical treatments for pancreatic cancer has led to one of the lowest five-year survival rates among all cancers. Recently, our laboratory has developed a novel series of isoprenylated coumarin derivatives that have exhibited anti-pancreatic cancer activity exclusively under nutrient-deprived conditions. In this study, we report the effect of the various cell culture medium components on the preferential cytotoxicity of our lead isoprenylated coumarin compound against the pancreatic adenocarcinoma cell line PANC-1. In particular, our findings show a clear link between observed cytotoxicity and glucose deprivation, suggesting that our compound targets a salvage pathway when glycolysis is no longer an option for cancer cell survival. The cytotoxicity of our lead compound was also examined in vitro against two other pancreatic cancer cell lines, BxPC-3 and Capan-2 under both nutrient-rich and nutrient-deprived conditions.

Cancer immunotherapy for pancreatic cancer utilizing α-gal epitope/natural anti-Gal antibody reaction

Pancreatic ductal adenocarcinoma (PDAC) has the poorest prognosis of all malignancies and is largely resistant to standard therapy. Novel treatments against PDAC are desperately needed. Anti-Gal is the most abundant natural antibody in humans, comprising about 1% of immunoglobulins and is also naturally produced in apes and Old World monkeys. The anti-Gal ligand is a carbohydrate antigen called “α-gal epitopes” with the structure Galα1-3Galβ1-4GlcNAc-R. These epitopes are expressed as major carbohydrate antigens in non-primate mammals, prosimians, and New World monkeys. Anti-Gal is exploited in cancer vaccines to increase the immunogenicity of antigen-presenting cells (APCs). Cancer cells or PDAC tumor lysates are processed to express α-gal epitopes. Vaccination with these components results in in vivo opsonization by anti-Gal IgG in PDAC patients. The Fc portion of the vaccine-bound anti-Gal interacts with Fcγ receptors of APCs, inducing uptake of the vaccine components, transport of the vaccine tumor membranes to draining lymph nodes, and processing and presentation of tumor-associated antigens (TAAs). Cancer vaccines expressing α-gal epitopes elicit strong antibody production against multiple TAAs contained in PDAC cells and induce activation of multiple tumor-specific T cells. Here, we review new areas of clinical importance related to the α-gal epitope/anti-Gal antibody reaction and the advantages in immunotherapy against PDAC.

Isoquercitrin inhibits the progression of pancreatic cancer in vivo and in vitro by regulating opioid receptors and the mitogen-activated protein kinase signalling pathway

Pancreatic cancer is a common malignant tumour that affects individuals worldwide. In recent years, the incidence and mortality rates of pancreatic cancer have continuously increased. Currently, the primary clinical treatment methods for pancreatic cancer include surgical resection, chemotherapy and radiotherapy. However, these treatment methods rarely produce satisfactory therapeutic outcomes. Extensive research has also proven that the effective components of several traditional Chinese medicines, particularly flavonoids extracted from plants, have significant antitumour effects. Isoquercitrin, which is one of the flavonoids found in Bidens pilosa extracts, has a significant antitumour effect. However, the antitumour effect of isoquercitrin and its mechanism of action remain unclear. The objective of the present study was to investigate the effect of isoquercitrin on the progression of pancreatic cancer and to further understand the biological characteristics of the participation of isoquercitrin in the progression of pancreatic cancer. In vitro, we found that a therapeutic dose of isoquercitrin significantly inhibited proliferation, promoted apoptosis and induced cell cycle arrest within the G1 phase in pancreatic cancer cells. Isoquercitrin activated caspase-3, -8 and -9 and reduced the mitochondrial membrane potential. In addition, isoquercitrin inhibited the expression level of the δ opioid receptor; however, isoquercitrin had no effect on the κ and µ opioid receptors. Furthermore, isoquercitrin inhibited extracellular signal-regulated kinase (ERK) phosphorylation and promoted c-Jun N-terminal kinase (JNK) phosphorylation. In vivo, we found that a therapeutic dose of isoquercitrin significantly inhibited xenograft growth in nude mice. In summary, the present study demonstrated that isoquercitrin inhibits human pancreatic cancer progression in vivo and in vitro and that its molecular mechanism may be closely related to opioid receptors and to the activation of the mitogen-activated protein kinase (MAPK) signalling pathway.

Vaccine therapy for pancreatic cancer

Pancreatic cancer is a lethal disease and currently available therapies have significant limitations. Pancreatic cancer is thus an ideal setting for the development of novel treatment modalities such as immunotherapy. However, relevant obstacles must be overcome for immunotherapeutic regimens against pancreatic cancer to be successful. Vaccine therapy relies on the administration of biological preparations that include an antigen that (at least ideally) is specifically expressed by malignant cells, boosting the natural ability of the immune system to react against neoplastic cells. There are a number of ways to deliver anticancer vaccines. Potent vaccines stimulate antigen presentation by dendritic cells, hence driving the expansion of antigen-specific effector and memory T cells. Unlike vaccines given as a prophylaxis against infectious diseases, anticancer vaccines require the concurrent administration of agents that interfere with the natural predisposition of tumors to drive immunosuppression. The safety and efficacy of vaccines against pancreatic cancer are nowadays being tested in early phase clinical trials.

Pancreatic intraepithelial neoplasia and histological changes in non-neoplastic pancreas associated with neoadjuvant therapy in patients with pancreatic ductal adenocarcinoma

AIMS

To study the histological changes in non-neoplastic pancreas and the effects on pancreatic intraepithelial neoplasia (PanIN) after neoadjuvant chemoradiation therapy (NCRT) for pancreatic ductal adenocarcinoma (PDAC).

METHODS AND RESULTS

We reviewed the archival H&E slides from 218 patients with PDAC who completed NCRT and pancreaticoduodenectomy. Sixty-five patients who underwent pancreaticoduodenectomy for PDAC without NCRT were used as controls. Various histological features were reviewed and correlated with NCRT and survival. The NCRT group had lower densities of PanIN2 (P = 0.004) and PanIN3 (P = 0.02) than the control group. The extent of fibrosis, the frequency of neuroma-like nerve proliferation and the frequency of islet cell aggregation were significantly higher in the NCRT group than in the control group (P < 0.05). The intensity of inflammation was less in the NCRT group than in the control group (P = 0.02). In the NCRT group, patents with moderate to severe fibrosis or grade 2 inflammation had poorer survival than those with mild fibrosis (P = 0.04) or those with grade 0 or grade 1 inflammation (P = 0.003), respectively.

CONCLUSIONS

Non-neoplastic pancreatic tissue from patients who received NCRT had a reduced density of high-grade PanIN lesions, more pancreatic fibrosis, and higher frequencies of neuroma-like nerve proliferation and islet cell aggregation, but less inflammation, compared to tissue from those who did not receive NCRT.

Adjuvant treatments for resected pancreatic adenocarcinoma: a systematic review and network meta-analysis

BACKGROUND

Major adjuvant treatments for pancreatic adenocarcinoma include fluorouracil, gemcitabine, chemoradiation, and chemoradiation plus fluorouracil or gemcitabine. Since the optimum regimen remains inconclusive, we aimed to compare these treatments in terms of overall survival after tumour resection and in terms of grade 3-4 toxic effects with a systematic review and random-effects Bayesian network meta-analysis.

METHODS

We searched PubMed, trial registries, and related reviews and abstracts for randomised controlled trials comparing the above five treatments with each other or observation alone before April 30, 2013. We estimated relative hazard ratios (HRs) for death and relative odds ratios (ORs) for toxic effects among different therapies by combining HRs for death and survival durations and ORs for toxic effects of included trials. We assessed the effects of prognostic factors on survival benefits of adjuvant therapies with meta-regression.

FINDINGS

Ten eligible articles reporting nine trials were included. Compared with observation, the HRs for death were 0·62 (95% credible interval 0·42-0·88) for fluorouracil, 0·68 (0·44-1·07) for gemcitabine, 0·91 (0·55-1·46) for chemoradiation, 0·54 (0·15-1·80) for chemoradiation plus fluorouracil, and 0·44 (0·10-1·81) for chemoradiation plus gemcitabine. The proportion of patients with positive lymph nodes was inversely associated with the survival benefit of adjuvant treatments. After adjustment for this factor, fluorouracil (HR 0·65, 0·49-0·84) and gemcitabine (0·59, 0·41-0·83) improved survival compared with observation, whereas chemoradiation resulted in worse survival than fluorouracil (1·69, 1·12-2·54) or gemcitabine (1·86, 1·04-3·23). Chemoradiation plus gemcitabine was ranked the most toxic, with significantly higher haematological toxic effects than second-ranked chemoradiation plus fluorouracil (OR 13·33, 1·01-169·36).

INTERPRETATION

Chemotherapy with fluorouracil or gemcitabine is the optimum adjuvant treatment for pancreatic adenocarcinoma and reduces mortality after surgery by about a third. Chemoradiation plus chemotherapy is less effective in prolonging survival and is more toxic than chemotherapy.

FUNDING

None.

Role of α-gal epitope/anti-Gal antibody reaction in immunotherapy and its clinical application in pancreatic cancer

Pancreatic cancer is one of the most common causes of death from cancer. Despite the availability of various treatment modalities, such as surgery, chemotherapy and radiotherapy, the 5-year survival remains poor. Although gemcitabine-based chemotherapy is typically offered as the standard care, most patients do not survive longer than 6 months. Therefore, new therapeutic approaches are needed. The α-gal epitope (Galα1-3Galβ1-4GlcNAc-R) is abundantly synthesized from glycoproteins and glycolipids in non-primate mammals and New World monkeys, but is absent in humans, apes and Old World monkeys. Instead, they produce anti-Gal antibody (Ab) (forming approximately 1% of circulating immunoglobulins), which specifically interacts with α-gal epitopes. Anti-Gal Ab can be exploited in cancer immunotherapy as vaccines that target antigen-presenting cells (APC) to increase their immunogenicity. Tumor cells or tumor cell membranes from pancreatic cancer are processed to express α-gal epitopes. Subsequent vaccination with such processed cell membranes results in in vivo opsonization by anti-Gal IgG in cancer patients. The interaction of the Fc portion of the vaccine-bound anti-Gal with Fcγ receptors of APC induces effective uptake of the vaccinating tumor cell membranes by the APC, followed by effective transport of the vaccinating tumor membranes to the regional lymph nodes, and processing and presentation of the tumor-associated antigens. Activation of tumor-specific B and T cells could elicit an immune response that in some patients is potent enough to eradicate the residual cancer cells that remain after completion of standard therapy. This review addresses these topics and new avenues of clinical importance related to this unique antigen/antibody system (α-gal epitope/anti-Gal Ab) and advances in immunotherapy in pancreatic cancer.

Novel multimodality treatment sequencing for extrahepatic (mid and distal) cholangiocarcinoma

Neoadjuvant chemoradiation has demonstrated significant advantages in the management of pancreatic adenocarcinoma. A similar tumor in a nearby anatomical location is extrahepatic cholangiocarcinoma, which has proven to be largely unresponsive to current forms of therapy. Neoadjuvant therapy for hilar cholangiocarcinoma has been combined with surgical resection and/or liver transplantation with a 25-33 % complete pathological response rate. We propose a wider application of neoadjuvant chemoradiation for patients with distal cholangiocarcinoma and present our rationale for this form of treatment sequencing.

A novel biliary stent loaded with (125)I seeds in patients with malignant biliary obstruction: preliminary results versus a conventional biliary stent

BACKGROUND & AIMS

Stenting is a palliative therapy method for relieving malignant biliary obstruction. The aim of this study was to evaluate the safety and effectiveness of an irradiation stent compared to a conventional biliary stent in patients with biliary obstruction caused by both primary and metastatic adenocarcinomas.

METHODS

Participants were randomly assigned to receive treatment with a biliary irradiation stent (irradiation stent group) or a conventional biliary stent (control group). After stent implantation, the outcomes were measured in terms of relief of obstructive jaundice, survival time, complications related to the procedure. A p value of less than 0.05 indicated a significant difference.

RESULTS

The stents were successfully placed in all the 23 patients. The obstructive jaundice was relieved in all patients except three in the control group. The median and mean overall survivals in the irradiation stent group were higher than those in the control group (7.40 months versus 2.50 months, 8.03 months versus 3.36 months, p=0.006). The patients with stent patent at 3, 6, and 12 months in the irradiation stent group were 11 (91.7%), 7 (58.3%), and 1 (8.3%), respectively. While in the control group, 4 (36.4%), 1 (9.1%), and 0 (0%), respectively. There were no significant differences in the complications related to stent insertion between the two groups.

CONCLUSIONS

This interim analysis shows that treatment with the biliary intraluminal irradiation stent in patients with biliary obstruction caused by adenocarcinomas appears safe and technically feasible, has benefits in relieving jaundice, and seems to extend survival when compared to a conventional biliary stent.

Assessing treatment effect in pancreatic cancer

CONTEXT

Pancreatic cancer is one of the most deadly forms of cancer (43,140 new cases per year; 36,800 deaths), and most people with pancreatic cancer do not survive past 5 years. New therapeutic regimens are constantly being evaluated in an attempt to reduce the rapid progression of this disease. Although some patients receive neoadjuvant therapy in an attempt to make a nonresectable or borderline-resectable tumor resectable, more patients with resectable disease are being enrolled in clinical trials that provide neoadjuvant therapy. This means more pancreatic resections must be evaluated for therapy effect. Histologic grading schemes for the assessment of posttherapy response have been described, but difficulties associated with determining the histologic features of treatment effect in pancreatic cancer have not been addressed.

OBJECTIVES

To critically review the diagnostic criteria for proposed grading schemes for pancreatic cancer treated with neoadjuvant chemoradiation therapy and to provide guidance to surgical pathologists who encounter treated pancreatic cancer resections.

DATA SOURCES

Published peer-reviewed literature and the personal experience of the authors.

CONCLUSIONS

Assessment of treatment effect in pancreatic cancer is difficult. Pathologists need to be aware that some histologic features of treatment effect overlap with histologic features seen in untreated pancreatic cancer, such as tumor cell anaplasia, necrosis, and fibrosis. Careful assessment of pancreatic resections, including detailed gross examination and thorough histologic sampling, is important in accurately assessing treatment effect and improving patient outcomes.

Post-therapy pathologic stage and survival in patients with pancreatic ductal adenocarcinoma treated with neoadjuvant chemoradiation

BACKGROUND

Neoadjuvant chemoradiation before surgery is an emerging treatment modality for pancreatic ductal adenocarcinoma (PDAC). However, analysis of prognostic factors is limited for patients with PDAC treated with neoadjuvant chemoradiation and pancreaticoduodenectomy (PD).

METHODS

The study population was comprised of 240 consecutive patients with PDAC who received neoadjuvant chemoradiation and PD and was compared with 60 patients who had no neoadjuvant therapy between 1999 and 2007. Clinicopathologic features were correlated with disease-free survival (DFS) and overall survival (OS).

RESULTS

Among the 240 treated patients, the 1-year and 3-year DFS rates were 52% and 32%, with a median DFS of 15.1 months. The 1-year and 3-year OS rates were 95% and 47%, with a median OS of 33.5 months. By univariate analysis, DFS was associated with age, post-therapy tumor stage (ypT), lymph node status (ypN), number of positive lymph nodes, and American Joint Committee on Cancer (AJCC) stage, whereas OS was associated with intraoperative blood loss, margin status, ypT, ypN, number of positive lymph nodes, and AJCC stage. By multivariate analysis, DFS was independently associated with age, number of positive lymph nodes, and AJCC stage, and OS was independently associated with differentiation, margin status, number of positive lymph nodes, and AJCC stage. In addition, the treated patients had better OS and lower frequency of lymph node metastasis than those who had no neoadjuvant therapy.

CONCLUSIONS

In patients with PDAC who received neoadjuvant chemoradiation and subsequent PD, post-therapy pathologic AJCC stage and number of positive lymph nodes are independent prognostic factors.

Potential targets for pancreatic cancer immunotherapeutics

Pancreatic adenocarcinoma is the fourth leading cause of cancer death with an overall 5-year survival of less than 5%. As there is ample evidence that pancreatic adenocarcinomas elicit antitumor immune responses, identification of pancreatic cancer-associated antigens has spurred the development of vaccination-based strategies for treatment. While promising results have been observed in animal tumor models, most clinical studies have found only limited success. As most trials were performed in patients with advanced pancreatic cancer, the contribution of immune suppressor mechanisms should be taken into account. In this article, we detail recent work in tumor antigen vaccination and the recently identified mechanisms of immune suppression in pancreatic cancer. We offer our perspective on how to increase the clinical efficacy of vaccines for pancreatic cancer.

Genetic effects and modifiers of radiotherapy and chemotherapy on survival in pancreatic cancer

OBJECTIVES

Germ-line genetic variation may affect clinical outcomes of cancer patients. We applied a candidate-gene approach to evaluate the effect of putative markers on survival of patients with pancreatic cancer. We also examined gene-radiotherapy and gene-chemotherapy interactions, aiming to explain interindividual differences in treatment outcomes.

METHODS

In total, 211 patients with pancreatic cancer were recruited in a population-based study. Sixty-four candidate genes associated with cancer survival or treatment response were selected from existing publications. Genotype information was obtained from a previous genome-wide association study data set. The main effects of genetic variation and gene-specific treatment interactions on overall survival were examined by proportional hazards regression models.

RESULTS

Fourteen genes showed evidence of association with pancreatic cancer survival. Among these, rs1760217, located at the DPYD gene; rs17091162 at SERPINA3; and rs2231164 at ABCG2 had the lowest P of 10(-4.60), 0.0013, and 0.0023, respectively. We also observed that 2 genes, RRM1 and IQGAP2, had significant interactions with radiotherapy in association with survival, and 2 others, TYMS and MET, showed evidence of interaction with 5-fluorouracil and erlotinib, respectively.

CONCLUSIONS

Our study suggested significant associations between germ-line genetic polymorphisms and overall survival in pancreatic cancer, as well as survival interactions between various genes and radiotherapy and chemotherapy.