Neoadjuvant therapy for unresectable pancreatic adenocarcinoma

Phase II Study of Induction Chemotherapy with Gemcitabine plus 5-Fluorouracil Followed by Gemcitabine-Based Concurrent Chemoradiotherapy for Unresectable Locally Advanced Pancreatic Cancer

Aims and background

To evaluate the efficacy and tolerability of a new treatment approach including induction chemotherapy (CT) and concurrent chemoradiotherapy (CRT) in unresectable, locally advanced pancreatic cancer (LAPC).

Patients and methods

Twenty-four patients with LAPC were enrolled in the study. They first received induction CT consisting of 5-fluorouracil (5FU) (500 mg/m2) and gemcitabine (1000 mg/m2), which were given weekly for 3 weeks of every 4. Patients showing a response or disease stabilization after 2 cycles of induction CT received CRT consisting of external beam radiotherapy (50.4-54 Gy in fractions of 1.8 Gy/day) and gemcitabine (350 mg/m2, weekly for 6 weeks). Patients without disease progression received 2 additional cycles of CT consisting of 5FU plus gemcitabine with the same doses and schedule as given in the induction CT.

Results

After the end of the study, 2 (8%) and 5 (21%) patients showed complete and partial responses, respectively. Five patients (21%) had disease stabilization. The grade 3 and 4 toxicities associated with CT were neutropenia (21%) and thrombocytopenia (4%). The grade 3 and 4 toxicities occurring in patients who received CRT were neutropenia (24%), thrombocytopenia (24%), diarrhea (18%), and nausea (12%). The median progression-free survival for all patients was 6 months (95% CI, 3.6-8.4), and the median overall survival was 11 months (95% CI, 8.16-13.84).

Conclusions

The CRT approach of this study is moderately active and has an acceptable toxicity profile. However, the incor-poration of combination CT into CRT at the present schedule could not produce any additional benefit over CRT alone. Newer agents with more systemic activity are clearly warranted.

Preoperative Chemoradiation and Intra-Operative Radiotherapy for Pancreatic Carcinoma

Aims and background

In recent years, preoperative chemoradiation has received growing interest for the treatment of locally advanced pancreatic cancer. In an attempt to improve resectability and disease control, we used preoperative radiation therapy and concomitant 5-fluorouracil in a combined modality therapy protocol. The aim of the study was to evaluate definitive results in terms of toxicity, response and clinical outcome.

Material and methods

Twenty-eight patients with unresectable (cT4,19 patients) or resectable (cT3, 9 patients) nonmetastatic pancreatic tumors received radiotherapy (39.6 Gy) plus 5-fluorouracil (continuous infusion, days 1-4 at 1000 mg/m2/day). After 4 weeks, patients were evaluated for surgical resection. In 9 resected patients, electron-beam intra-operative radiotherapy (10 Gy) was given before reconstruction. Thereafter, in resected patients, adjuvant chemotherapy was prescribed.

Results

During chemoradiation, 1 patient (3.6%) developed grade 3 acute gastrointestinal toxicity and 2 patients (7.1%) developed grade 3 hematological toxicity. Three of 19 patients with unresectable tumors had tumor downstaging (15.8%). Two patients showed partial response (response rate, 7.1%; 95% CI, 0.2-25.3) and 4 patients (14.3%) had minimal tumor response. Four patients (14.3%) showed progressive disease after chemoradiation. One postoperative death was recorded. The median survival time was 11.3 months (20.5 and 9.0 months in resected and unresected patients, respectively). Only one local failure was recorded in 8 patients resected with negative margins.

Conclusions

Although the response rate is still low, our preliminary results suggest that preoperative 5-fluorouracil chemoradiation is well tolerated and may result in tumor downstaging. Delivery of intra-operative radiotherapy seems to be associated with a low rate of local recurrences.

Adjuvant or Neoadjuvant Therapy in the Treatment in Pancreatic Malignancies: Where Are We?

Since the advent of modern surgery for pancreatic cancer, clinicians have recognized this cancer's propensity to recur locally, metastasize, and cause death. Despite significant efforts to improve patient outcomes with better adjuvant therapy, only modest gains in survival have been observed. An alternative strategy of neoadjuvant therapy followed by surgery has the potential to improve patient selection and survival, and expand the pool of patients eligible for curative surgery. This article summarizes large, randomized trials of adjuvant therapy, explains the limitations imposed by up-front surgery, and suggests neoadjuvant therapy as a rational alternative to initial surgery and adjuvant therapy.

Pancreatic adenocarcinoma: effects of neoadjuvant therapy on post-pancreatectomy outcomes - an American College of Surgeons National Surgical Quality Improvement Program targeted variable review

BACKGROUND

As the incidence of pancreatic adenocarcinoma increases, so has the utilization of neoadjuvant therapy. The objective of this study was to evaluate outcomes in patients undergoing neoadjuvant therapy or surgery first for pancreatic adenocarcinoma.

METHODS

The ACS-NSQIP 2014-2015 targeted pancreatectomy variables were queried for patients with pancreatic adenocarcinoma who underwent resection. Outcomes of those receiving neoadjuvant therapy were compared to surgery first using a multivariate, logistic regression model.

RESULTS

3408 patients underwent pancreatectomy; 2596 proximal pancreatectomies, 741 distal pancreatectomies, 64 total pancreatectomies and 7 other pancreatic procedures were performed. Of the 3408 patients identified, 934 (27.5%) received neoadjuvant therapy: 496 chemotherapy alone, 28 radiation alone, and 410 combined chemotherapy/radiation therapy. Overall morbidity and mortality were similar between patients receiving neoadjuvant therapy versus those who underwent surgery first. Neoadjuvant treatment was associated with lower rates of pancreatic fistulas (10.2% vs. 13.2%, P = 0.017), but higher intra/postoperative transfusion rates (27.4% vs. 20.3%, P < 0.0001).

CONCLUSIONS

Neoadjuvant therapy appeared to be safe prior to operative intervention as no difference in overall postoperative morbidity or mortality rates were identified. There were increased intra/postoperative transfusions in the neoadjuvant therapy group, but neoadjuvant therapy was associated with lower rates of pancreatic fistulas.

Biological determinants of radioresistance and their remediation in pancreatic cancer

Despite recent advances in radiotherapy, a majority of patients diagnosed with pancreatic cancer (PC) do not achieve objective responses due to the existence of intrinsic and acquired radioresistance. Identification of molecular mechanisms that compromise the efficacy of radiation therapy and targeting these pathways is paramount for improving radiation response in PC patients. In this review, we have summarized molecular mechanisms associated with the radio-resistant phenotype of PC. Briefly, we discuss the reversible and irreversible biological consequences of radiotherapy, such as DNA damage and DNA repair, mechanisms of cancer cell survival and radiation-induced apoptosis following radiotherapy. We further describe various small molecule inhibitors and molecular targeting agents currently being tested in preclinical and clinical studies as potential radiosensitizers for PC. Notably, we draw attention towards the confounding effects of cancer stem cells, immune system, and the tumor microenvironment in the context of PC radioresistance and radiosensitization. Finally, we discuss the need for examining selective radioprotectors in light of the emerging evidence on radiation toxicity to non-target tissue associated with PC radiotherapy.

The impact of neoadjuvant therapy on the histopathological features of pancreatic ductal adenocarcinoma - A systematic review and meta-analysis

BACKGROUND

Due to increased rates of curative tumor resections exceeding 60% after FOLFIRINOX-treatment, neoadjuvant therapy/NTx is increasingly recognized as an effective therapy option for downstaging borderline or locally advanced pancreatic ductal adenocarcinoma/PDAC. Yet, the effects of NTx on the common histopathological features of PDAC have not been systematically analysed. Therefore, the aim of the current study was to assess the impact of NTx on relevant histopathological features of PDAC.

PATIENTS AND METHODS

Biomedical databases were systematically screened for predefined searching terms related to NTx and PDAC. The Preferred-Reporting-Items-for-Systematic-review-and-Meta-Analysis/PRISMA-guidelines were used to perform a systematic review and meta-analysis. Articles meeting the predefined criteria were analysed on relevance, and a meta-analysis was performed.

RESULTS

A total of 9031 studies could be identified that analysed the effect of NTx on PDAC. Only 35 studies presented comparative data on the histological features of neoadjuvantly treated vs. upfront resected PDAC patients. In meta-analyses, the beneficial effect of NTx was reflected by reduced tumor size (T1/2: RR 2.87, 95%-CI: 1.52-5.42, P=0.001, T3/4: RR 0.78, 95%-CI: 0.69-0.89, P=0.0002), lower N-Stage (N0: RR 2.14, 95%-CI: 1.85-2.46, P<0.00001, N1: RR 0.59, 95%-CI: 0.53-0.65, P<0.00001), higher R0-rates (R0: RR 1.13, 95%-CI: 1.08-1.18, P<0.00001, R1: RR 0.66, 95%-CI: 0.58-0.76, P<0.00001), less perineural invasion (Pn1: RR 0.78, 95%-CI: 0.73-0.83, P<0.00001), less lymphatic vessel invasion (RR: 0.50, 95%-CI: 0.36-0.70, P<0.0001) and fewer G3-tumors (RR 0.82, 95%-CI: 0.71-0.94, P=0.005).

CONCLUSIONS

NTx in PDAC seems to exert its beneficial effect in borderline or locally advanced PDAC over genuine tumor downstaging. Thus, although at least 40% of all NTx treated patients remain unresectable even with modern NTx regimes, neoadjuvantly treated PDAC showed not only increasing resectability rates especially after FOLFIRINOX, but even reach a lower tumor stage than primarily resected PDAC.

Foretinib inhibits angiogenesis, lymphangiogenesis and tumor growth of pancreatic cancer in vivo by decreasing VEGFR-2/3 and TIE-2 signaling

Foretinib, a multiple kinase inhibitor undergoing clinical trials, could suppress the activity of hepatocyte growth factor (HGF) receptor c-MET and vascular endothelial growth factor receptor-2 (VEGFR-2). In addition, Foretinib may inhibit two critical lymphangiogenic signaling receptors VEGFR-3 and TIE-2. However, the effect of Foretinib on lymphatic endothelial cells (LECs) in vitro and lymphangiogenesis in vivo is still unknown. We found Foretinib decreased basal- and HGF-induced c-MET activity at low concentrations. However, Foretinib only reduced the proliferation of pancreatic cancer cells at high concentration reflecting the intrinsic chemoresistance of pancreatic cancer cells. Foretinib inhibited VEGF-A, VEGF-C and Angiopoetin-2 (ANG-2)-stimulated tube formation and sprouting of LECs by reducing VEGFR-2, VEGFR-3 and TIE-2 activation and increased apoptosis of LECs. In xenograft animal study, Foretinib suppressed tumor growth by inhibiting proliferation, angiogenesis and lymphangiogenesis. Additionally, Foretinib inhibited angiogenesis and lymphangiogenesis more significantly and exhibited low detrimental effect in orthotopic animal study. Collectively, we suggested that Foretinib simultaneously inhibits cancer cells and LECs to reduce pancreatic tumor growth in vivo and demonstrated for the first time that Foretinib suppresses angiogenesis and lymphangiogenesis by blocking VEGFR-2/3 and TIE-2 signaling.

Does the use of neoadjuvant therapy for pancreatic adenocarcinoma increase postoperative morbidity and mortality rates?

INTRODUCTION

The impact of neoadjuvant therapy on postpancreatectomy complications is inadequately described.

METHODS

Data from the NSQIP Pancreatectomy Demonstration Project (11/2011 to 12/2012) was used to identify patients with pancreatic adenocarcinoma who did and did not receive neoadjuvant therapy. Neoadjuvant therapy was classified as chemotherapy alone or radiation ± chemotherapy. Outcomes in the neoadjuvant vs. surgery first groups were compared.

RESULTS

Of 1,562 patients identified at 43 hospitals, 199 (12.7%) received neoadjuvant therapy (99 chemotherapy alone and 100 radiation ± chemotherapy). Preoperative biliary stenting (57.9 vs. 44.7%, p = 0.0005), vascular resection (41.5 vs. 17.3%, p < 0.0001), and open resections (94.0 vs. 91.4%, p = 0.008) were more common in the neoadjuvant group. Thirty-day mortality (2.0 vs. 1.5%, p = 0.56) and postoperative morbidity rates (56.3 vs. 52.8%, p = 0.35) were similar between groups. Neoadjuvant therapy patients had fewer organ space infections (3.0 vs. 10.3%, p = 0.001), and neoadjuvant radiation patients had fewer pancreatic fistulas (7.3 vs. 15.4%, p = 0.03).

CONCLUSIONS

Despite evidence for more extensive disease, patients receiving neoadjuvant therapy did not experience more complications. Neoadjuvant radiation was associated with lower pancreatic fistula rates. These data provide evidence against higher postoperative complication rates in patients with pancreatic cancer who are treated with neoadjuvant therapy.

Neoadjuvant therapy for non-metastatic pancreatic ductal adenocarcinoma

Treatment of pancreatic cancer is increasingly multimodal, with patients receiving chemotherapy, radiation, and surgical extirpation in hope of long-term cure. There is ongoing debate over the timing, sequence, and necessity of these treatments as they pertain to the spectrum of local-regional disease. Current guidelines support a neoadjuvant strategy in patients with locally advanced and borderline resectable disease. Although there is currently no high-level evidence to recommend neoadjuvant therapy for all patients, there are data to suggest that wider application of neoadjuvant therapy may be beneficial. Random-assignment prospective trials are ongoing. In this review we examine the literature addressing a neoadjuvant approach to potentially resectable, borderline resectable, and locally advanced pancreatic cancer and highlight the outcomes of preoperative emergence of latent metastatic disease, attempted resection rates, margin negative resection rates, and pathologic response to treatment.

Preoperative chemoradiation and IOERT for unresectable or borderline resectable pancreas cancer

BACKGROUND AND OBJECTIVES

Pre-operative chemoradiation (preop CRT) plus intraoperative electron irradiation (IOERT) has been used in the multidisciplinary treatment for patients with locally advanced unresectable or borderline resectable pancreas cancer. This review was performed to evaluate survival, relapse patterns and prognostic factors in patients treated with curative intent.

METHODS

Between January 2002 and December 2010, 48 patients with locally advanced pancreatic ductal adenocarcinoma received preop CRT prior to an attempt at resection and IOERT. 31/48 (65%) patients proceeded to curative-intent surgical resection. Resection status prior to preop CRT was locally unresectable (20 patients) and borderline resectable (11 patients). Preop CRT (45-50.4 Gy/25-28 Fx in 27/31) was delivered with concurrent 5FU or gemcitabine-based regimens. Subsequent gross total resection was achieved in 16 patients (R0, 11; R1, 5). IOERT was delivered in 28 patients (dose, 10-20 Gy). 16 patients also received adjuvant post-operative systemic chemotherapy. Outcomes evaluated include survival, local failure in the EBRT field (LF), central failure in the IOERT field (CF), and distant metastases.

RESULTS

Resection status was predictive for survival and for patterns of relapse. For patients with at least a gross total resection after preop CRT (R0/R1; n=16) vs. no resection (n=15), both median and overall survival were improved (median 23 vs. 10 months; 2-year, 40% vs. 17%; 3-year, 40% vs. 0%; P=0.002). Liver or peritoneal relapse was documented in 22/31 patients (71%); LF/CF in 5/26 (16%).

CONCLUSIONS

Long term survival and disease control are achievable in select patients with borderline resectable or locally unresectable pancreas cancer when gross total surgical resection is achieved after preop CRT. Continued evaluation of curative-intent combined modality therapy is warranted in this high risk population, but additional strategies are needed to improve resectability and disease control.

Self-expanding metal stents (SEMS) for preoperative biliary decompression in patients with resectable and borderline-resectable pancreatic cancer: outcomes in 241 patients

BACKGROUND AND AIM

Obstructive jaundice caused by distal biliary obstruction can present in up to 70 % of patients with localized cancer of the head of the pancreas. The aim of this study was to report our experience in using self-expanding metal stents (SEMS) for preoperative biliary decompression in patients with resectable and borderline resectable carcinoma of the pancreatic head.

METHODS

We performed a retrospective study evaluating patients from two tertiary referral centers. Two-hundred and forty-one patients with resectable and borderline resectable pancreatic carcinoma underwent ERCP with metal biliary stent placement between September 2006 and August 2011. We assessed the effectiveness of SEMS to adequately decompress the biliary tree, procedural success, patient survival, stent patency, and stent-related complications.

RESULTS

Two-hundred and forty-one patients were evaluated [123 male, mean age (± SD) 67.4 ± 9.8 years; resectable 174, borderline resectable 67]. Patients with borderline-resectable cancer underwent neoadjuvant therapy and restaging before possible curative surgery. Successful placement of a metal biliary stent was achieved in all patients and improved jaundice. Patients were followed for mean duration of 6.3 months. The overall survival was 49 % at 27 months. Fourteen (5.8 %) patients experienced stent occlusion; the mean time to stent occlusion was 6.6 (range 1-20) months. Immediate complications included: post-ERCP pancreatitis (n = 14), stent migration (n = 3), and duodenal perforation (n = 3). Long-term complications included stent migration (n = 9) and hepatic abscess (n = 1). A total of 144/174 patients deemed to have resectable cancer at time of diagnosis underwent curative surgery. Due to disease progression or the discovery of metastasis after neoadjuvant therapy, only 22/67 patients with borderline-resectable cancer underwent curative surgery.

CONCLUSIONS

SEMS should be considered for patients with obstructive jaundice and resectable or borderline resectable pancreatic cancer, especially if surgery is not planned immediately as a result of preoperative chemoradiation. These stents appear to be safe and effective.

Role of neoadjuvant therapy and adjuvant therapy in treatment of pancreatic cancer

Pancreatic cancer is a highly malignant tumor that has a low resection rate. In Western countries, pancreatic cancer is the fourth cause of death in malignant tumors. Combined therapy is particularly important for the treatment of pancreatic cancer. Preoperative neoadjuvant therapy and postoperative adjuvant therapy are important parts of combined treatment for pancreatic cancer. Adjuvant therapy can improve survival and quality of life of patients with pancreatic cancer, and neoadjuvant therapy can reduce the primary lesion and lymph node metastasis, provide patients with the possibility of surgery to improve radical resection, decrease intraoperative bleeding and postoperative complications, and improve postoperative survival and life quality of patients. This article reviews the role of adjuvant therapy and neoadjuvant therapy in the management of pancreatic cancer.

Prospective efficacy and safety study of neoadjuvant gemcitabine with capecitabine combination chemotherapy for borderline-resectable or unresectable locally advanced pancreatic adenocarcinoma

BACKGROUND

To determine the safety and efficacy of neoadjuvant gemcitabine/capecitabine followed by surgery for the treatment of locally advanced pancreatic adenocarcinoma (LAPC).

METHODS

Patients with histologically confirmed LAPC were given 3-6 cycles of fixed-dose rate gemcitabine/capecitabine every 3 weeks. At the end of chemotherapy, patients were restaged and underwent surgery if the disease was not classified as unresectable. Our institutional criteria were used to classify respectability, which was recategorized on the basis of National Comprehensive Cancer Network (NCCN) criteria retroactively. The primary end point was rate of microscopic curative resection.

RESULTS

Forty-three eligible patients (18 with borderline resectable disease and 25 with unresectable disease on the basis of NCCN criteria) were enrolled. The radiologic response rate was 18.6%. Grade three or worse adverse events were mainly hand-foot syndrome (11%), and there were no grade four adverse events. Surgery was performed in 17 patients (39.5%); pathologic curative resection (R0) was achieved in 14 patients (32.5%) among total 43 patients, and 82.3% (14/17) among the 17 resected patients. With 43-month follow-up, the median overall was 16.6 months with a median progression-free survival of 10.0 months. Median overall survival was 23.1 months in patients who underwent surgery and 13.2 months in patients who could not complete the surgery (P = .017).

CONCLUSION

A subset of patients with borderline or unresectable pancreatic cancer could be performed curative tumor resection after neoadjuvant chemotherapy. Some patients might be benefit on survival from neoadjuvant chemotherapy after surgical resection.

Acquisition of resistance of pancreatic cancer cells to 2-methoxyestradiol is associated with the upregulation of manganese superoxide dismutase

Acquired resistance of cancer cells to anticancer drugs or ionizing radiation (IR) is one of the major obstacles in cancer treatment. Pancreatic cancer is an exceptional aggressive cancer, and acquired drug resistance in this cancer is common. Reactive oxygen species (ROS) play an essential role in cell apoptosis, which is a key mechanism by which radio- or chemotherapy induce cell killing. Mitochondria are the major source of ROS in cells. Thus, alterations in the expression of mitochondrial proteins, involved in ROS production or scavenging, may be closely linked to the resistance of cancer cells to radio- or chemotherapy. In the present study, we generated a stable cell line by exposing pancreatic cancer cells to increasing concentrations of ROS-inducing, anticancer compound 2-methoxyestradiol (2-ME) over a 3-month period. The resulting cell line showed strong resistance to 2-ME and contained an elevated level of ROS. We then used a comparative proteomics method to profile the differential expression of mitochondrial proteins between the parental and the resistant cells. One protein identified to be upregulated in the resistant cells was manganese superoxide dismutase (SOD2), a mitochondrial protein that converts superoxide radicals to hydrogen peroxides. Silencing of SOD2 resensitized the resistant cells to 2-ME, and overexpression of SOD2 led the parental cells to 2-ME resistance. In addition, the 2-ME-resistant cells also showed resistance to IR. Our results suggest that upregulation of SOD2 expression is an important mechanism by which pancreatic cancer cells acquire resistance to ROS-inducing, anticancer drugs, and potentially also to IR.

Adjuvant and neoadjuvant treatment in pancreatic cancer

Pancreatic adenocarcinoma is one of the most aggressive human malignancies, ranking 4th among causes for cancer-related death in the Western world including the United States. Surgical resection offers the only chance of cure, but only 15 to 20 percent of cases are potentially resectable at presentation. Different studies demonstrate and confirm that advanced pancreatic cancer is among the most complex cancers to treat and that these tumors are relatively resistant to chemotherapy and radiotherapy. Currently there is no consensus around the world on what constitutes “standard” adjuvant therapy for pancreatic cancer. This controversy derives from several studies, each fraught with its own limitations. Standards of care also vary somewhat with regard to geography and economy, for instance chemo-radiotherapy followed by chemotherapy or vice versa is considered the optimal therapy in North America while chemotherapy alone is the current standard in Europe. Regardless of the efforts in adjuvant and neoadjuvant improved therapy, the major goal to combat pancreatic cancer is to find diagnostic markers, identifying the disease in a pre-metastatic stage and making a curative treatment accessible to more patients. In this review, authors examined the different therapy options for advanced pancreatic patients in recent years and the future directions in adjuvant and neoadjuvant treatments for these patients.

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.

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.

A systematic review and meta-analysis of survival and surgical outcomes following neoadjuvant chemoradiotherapy for pancreatic cancer

INTRODUCTION

This systematic review and meta-analysis aims to characterize the surgically important benefits and complications associated with the use of neoadjuvant chemoradiotherapy for the treatment of both resectable and initially unresectable pancreatic cancer. Studies were identified through a systematic literature search and analyzed by two independent reviewers. Survival, peri-operative complications, death rate, pancreatic fistula rate, and the incidence of involved surgical margins were analyzed and subject to meta-analysis.

METHODS

Nineteen studies, involving 2,148 patients were identified. Only cohort studies were included.

RESULTS

The meta-analysis found that patients with unresectable pancreatic cancer who underwent neoadjuvant chemoradiotherapy achieved similar survival outcomes to patients with resectable disease, even though only 40% were ultimately resected. Neoadjuvant chemoradiotherapy was not associated with a statistically significant increase in the rate of pancreatic fistula formation or total complications.

CONCLUSION

Patients receiving neoadjuvant chemoradiotherapy were less likely to have a positive resection margin, although there was an increase in the risk of peri-operative death.

A systematic review and meta-analysis of survival and surgical outcomes following neoadjuvant chemoradiotherapy for pancreatic cancer

INTRODUCTION

This systematic review and meta-analysis aims to characterize the surgically important benefits and complications associated with the use of neoadjuvant chemoradiotherapy for the treatment of both resectable and initially unresectable pancreatic cancer. Studies were identified through a systematic literature search and analyzed by two independent reviewers. Survival, peri-operative complications, death rate, pancreatic fistula rate, and the incidence of involved surgical margins were analyzed and subject to meta-analysis.

METHODS

Nineteen studies, involving 2,148 patients were identified. Only cohort studies were included.

RESULTS

The meta-analysis found that patients with unresectable pancreatic cancer who underwent neoadjuvant chemoradiotherapy achieved similar survival outcomes to patients with resectable disease, even though only 40% were ultimately resected. Neoadjuvant chemoradiotherapy was not associated with a statistically significant increase in the rate of pancreatic fistula formation or total complications.

CONCLUSION

Patients receiving neoadjuvant chemoradiotherapy were less likely to have a positive resection margin, although there was an increase in the risk of peri-operative death.

Chemoradiation therapy in the management of gastrointestinal malignancies

Concurrent administration of chemotherapy and radiotherapy has been increasingly used in cancer treatment, leading to improvements in survival as well as quality of life. Currently, it is a feasible preference, often regarded as the standard therapeutic option, for many locally confined solid tumors, including anal, bladder, cervical, esophageal, gastric, head and neck, lung, pancreatic and rectal cancers. In patients with these tumors, combined modality therapy improves local tumor control and survival while, in some instances, obviating the need for surgical removal of the organ of origin. The scientific rationale for the use of chemoradiation derives from the preclinical and clinical observations of synergistic interactions between radiotherapy and chemotherapy. When chemotherapy and radiotherapy are administered together, the chemotherapeutic agents can sensitize the cancer cells to the effects of ionizing radiation, leading to increased tumor-killing effects within the radiotherapy field. This, in turn, can improve local control of the primary tumor and, in some cancers, render surgical resection unnecessary. In other cases, patients with tumors that were initially considered unresectable are able to undergo curative interventions after completing chemoradiation. The chemotherapy component can address any potential micrometastatic disease that, without therapy, leads to an increased risk of distant recurrence. A large body of evidence exists that supports the use of chemoradiotherapy in gastrointestinal cancers. In fact, one of the first tumor types in which the superior efficacy of chemoradiation was described was anal cancer. Since then, chemoradiotherapy has been explored in other gastrointestinal malignancies with superior outcomes when compared with either radiation or chemotherapy alone. This article aims to recapitulate the clinical evidence supporting the use of chemoradiotherapy in a variety of gastrointestinal tumor types.

Neoadjuvant therapy in patients with pancreatic cancer: a disappointing therapeutic approach?

Pancreatic cancer is a devastating disease. It is the fourth leading cause of cancer-related death in Germany. The incidence in 2003/2004 was 16 cases per 100.000 inhabitants. Of all carcinomas, pancreatic cancer has the highest mortality rate, with one- and five-year survival rates of 25% and less than 5%, respectively, regardless of the stage at diagnosis. These low survival rates demonstrate the poor prognosis of this carcinoma. Previous therapeutic approaches including surgical resection combined with adjuvant therapy or palliative chemoradiation have not achieved satisfactory results with respect to overall survival. Therefore, it is necessary to evaluate new therapeutic approaches. Neoadjuvant therapy is an interesting therapeutic option for patients with pancreatic cancer. For selected patients with borderline or unresectable disease, neoadjuvant therapy offers the potential for tumor downstaging, increasing the probability of a margin-negative resection and decreasing the occurrence of lymph node metastasis. Currently, there is no universally accepted approach for treating patients with pancreatic cancer in the neoadjuvant setting. In this review, the most common neoadjuvant strategies will be described, compared and discussed.

Neoadjuvant GTX chemotherapy and IMRT-based chemoradiation for borderline resectable pancreatic cancer

BACKGROUND AND OBJECTIVES

To improve the likelihood of achieving a margin-free resection, neoadjuvant induction chemotherapy with GTX (gemcitabine, docetaxel, and capecitabine) followed by 5-FU-IMRT was administered to patients with borderline resectable pancreatic cancer. The utility of computed tomography (CT), endoscopic ultrasound (EUS), positron emission tomography (PET), and CA 19-9 during diagnostic workup and assessment of response was also examined.

METHODS

Seventeen patients with borderline resectable pancreatic cancer received a median of three cycles of neoadjuvant GTX induction chemotherapy followed by 5-FU-IMRT with dose painting. CA 19-9, CT mass size, and PET SUV were examined before and after neoadjuvant treatment.

RESULTS

Diagnostic EUS and CT scans displayed similar mean mass sizes and extent of vascular involvement. Eight of the 17 patients achieved an R0 resection. Median CA 19-9 levels, CT mass size, and PET SUV all significantly decreased after neoadjuvant therapy. The median progression-free survival and overall survival were 10.48 and 15.64 months, respectively. Six patients are still alive.

CONCLUSIONS

Neoadjuvant GTX induction chemotherapy followed by 5-FU-IMRT shows promise in improving the likelihood of resectability with negative margins in borderline resectable pancreatic cancer. CT and EUS play complimentary roles during diagnostic workup. CT scans, CA 19-9, and PET scans are useful in judging response to neoadjuvant therapy.

Molecular characteristics of pancreatic ductal adenocarcinoma

Pancreatic cancer is an almost universally lethal disease and despite extensive research over the last decades, this has not changed significantly. Nevertheless, much progress has been made in understanding the pathogenesis of pancreatic ductal adenocarcinoma (PDAC) suggesting that different therapeutic strategies based on these new insights are forthcoming. Increasing focus exists on designing the so-called targeted treatment strategies in which the genetic characteristics of a tumor guide therapy. In the past, the focus of research was on identifying the most frequently affected genes in PDAC, but with the complete sequencing of the pancreatic cancer genome the focus has shifted to defining the biological function that the altered genes play. In this paper we aimed to put the genetic alterations present in pancreatic cancer in the context of their role in signaling pathways. In addition, this paper provides an update of the recent advances made in the development of the targeted treatment approach in PDAC.

Current surgical aspects of palliative treatment for unresectable pancreatic cancer

Despite all improvements in both surgical and other conservative therapies, pancreatic cancer is steadily associated with a poor overall prognosis and remains a major cause of cancer mortality. Radical surgical resection has been established as the best chance these patients have for long-term survival. However, in most cases the disease has reached an incurable state at the time of diagnosis, mainly due to the silent clinical course at its early stages. The role of palliative surgery in locally advanced pancreatic cancer mainly involves patients who are found unresectable during open surgical exploration and consists of combined biliary and duodenal bypass procedures. Chemical splanchnicectomy is another modality that should also be applied intraoperatively with good results. There are no randomized controlled trials evaluating the outcomes of palliative pancreatic resection. Nevertheless, data from retrospective reports suggest that this practice, compared with bypass procedures, may lead to improved survival without increasing perioperative morbidity and mortality. All efforts at developing a more effective treatment for unresectable pancreatic cancer have been directed towards neoadjuvant and targeted therapies. The scenario of downstaging tumors in anticipation of a future oncological surgical resection has been advocated by trials combining gemcitabine with radiation therapy or with the tyrosine kinase inhibitor erlotinib, with promising early results.

Preoperative capecitabine and concurrent radiation for borderline resectable pancreatic cancer

BACKGROUND

Patients with borderline resectable pancreatic ductal adenocarcinoma (PDA) represent a high-risk group of patients due to tumor or patient-related characteristics. The optimal management of these patients has not been fully defined.

MATERIALS AND METHODS

All patients undergoing evaluation for PDA between 2005 and 2008 were identified. Clinical, radiographic, and pathological data were retrospectively reviewed. Patients were staged as borderline resectable using the M.D. Anderson Cancer Center (MDACC) classification.

RESULTS

A total of 170 patients with PDA were identified, 40 with borderline resectable disease. Of these, 34 borderline resectable patients (85%) completed neoadjuvant therapy and were restaged; pancreatic resection was completed in 16 patients (46%). Also, 8 patients completed 50 Gy of radiation in 28 fractions in 6 weeks, whereas 8 patients received 50 Gy in 20 fractions in 4 weeks plus chronomodulated capecitabine. An R0 resection was achieved in 12 of the 16 patients (75%). Also, 5 patients (63%) treated in 20 fractions had >90% pathologic response versus 1 (13%) treated in 28 fractions (P < .05). Borderline resectable patients completing surgery had similar survival to patients with resectable disease who underwent surgery. Patients receiving accelerated fractionation radiation had improved survival compared with patients treated with standard fractionation protocol.

CONCLUSIONS

A neoadjuvant approach to borderline resectable PDA identifies patients who are most likely to benefit from pancreatic resection. Preoperative capecitabine-based chemoradiation is an effective, well-tolerated treatment for these patients. Neoadjuvant therapy for borderline resectable PDA warrants further investigation using treatment schedules that can safely intensify irradiation dose.

Current and emerging therapies for the treatment of pancreatic cancer

Pancreatic adenocarcinoma carries a dismal prognosis and remains a significant cause of cancer morbidity and mortality. Most patients survive less than 1 year; chemotherapeutic options prolong life minimally. The best chance for long-term survival is complete resection, which offers a 3-year survival of only 15%. Most patients who do undergo resection will go on to die of their disease. Research in chemotherapy for metastatic disease has made only modest progress and the standard of care remains the purine analog gemcitabine. For resectable pancreatic cancer, presumed micrometastases provide the rationale for adjuvant chemotherapy and chemoradiation (CRT) to supplement surgical management. Numerous randomized control trials, none definitive, of adjuvant chemotherapy and CRT have been conducted and are summarized in this review, along with recent developments in how unresectable disease can be subcategorized according to the potential for eventual curative resection. This review will also emphasize palliative care and discuss some avenues of research that show early promise.

Management of borderline resectable pancreatic cancer

Borderline resectable pancreatic cancer is an emerging stage of disease defined by computed tomogrpahy criteria, patient (Katz type B), or disease characteristics (Katz type C). These patients are particularly well suited to a surgery-last strategy with induction therapy consisting of chemotherapy (gemcitabine alone or in combination) followed by chemoradiation. With appropriate selection and preoperative planning, many patients with borderline resectable disease derive clinical benefit from multimodality therapy. The use of a standardized system for the staging of localized pancreatic cancer avoids indecision and allows for the optimal treatment of all patients guided by the extent of their disease. In this article, 2 case reports are presented, and the term borderline resectable pancreatic cancer is discussed. The advantages of neoadjuvant therapy and surgery are also discussed.

Phase I trial of gemcitabine dose escalation with concurrent radiotherapy for patients with locally advanced pancreatic cancer

AIM

The safety and efficacy, and the dose-limiting toxicity (DLT) of the chemotherapeutic agent gemcitabine administered in conjunction with radiotherapy in patients with locally advanced pancreatic cancer are not yet established. Here, we evaluated the safety and efficacy, DLT, and maximum tolerated dose of gemcitabine with concurrent radiotherapy in patients with unresectable locally advanced pancreatic cancer. Tumor response and time to progression were also assessed.

PATIENTS AND METHODS

Patients with previously untreated pancreatic cancer (n = 12) received gemcitabine intravenously on days 1, 8, and 15. Concurrent radiation therapy was initiated on day 1 (40 Gy in 2 Gy/day x 20 fractions, days 1-5, 8-12, 15-19, 22-26). Patients received limited-field irradiation with three-dimensional radiotherapy. Dose escalation included dose levels 1-3 (gemcitabine 400, 600, and 800 mg/m(2)).

RESULTS

No patient developed DLT in this study. Of the 12 patients, there were 11 sustained responses, 0 partial responses, and 1 progressive disease. Two patients with a sustained response underwent surgery after re-evaluation. The median progression-free survival was 8 months, not including the patients that underwent surgery.

CONCLUSION

Weekly gemcitabine at a dose of 800 mg/m(2) with concurrent radiation therapy in patients with locally advanced pancreatic cancer was well tolerated. and IAP.

External beam radiotherapy plus 24-hour continuous infusion of gemcitabine in unresectable pancreatic carcinoma: long-term results of a phase II study

PURPOSE

To evaluate the efficacy of gemcitabine-based chemoradiation (CT-RT) in treating patients (pts) affected by locally advanced pancreatic cancers (LAPC).

METHODS AND MATERIALS

Weekly gemcitabine (100 mg/m(2)) was given as a 24-hour infusion during the course of three-dimensional radiotherapy (50.4 Gy to the tumor, 39.6 Gy to the nodes). After CT-RT, pts received five cycles of sequential chemotherapy with gemcitabine (1000 mg/m(2); 1, 8, q21). Response rate was assessed according to World Health Organization criteria 6 weeks after the end of CT-RT. Local control (LC), time to progression (TTP), metastases-free survival (MFS), and overall survival (OS) were analyzed by the Kaplan Meier method.

RESULTS

Forty pts (male/female 22/18; median age 62 years, range, 36-76) were treated from 2000 to 2005. The majority had T4 tumour (n = 34, 85%), six pts (15%) had T3 tumour. Sixteen pts (40%) were node positive at diagnosis. Grade 3-4 acute toxicity was observed in 21 pts (52.5%). Thirty pts (75%) completed the treatment schedule. A clinical response was achieved in 12 pts (30%). With a median follow-up of 76 months (range, 32-98), 2-year LC was 39.6% (median, 12 months), 2-year TTP was 18.4% (median, 10 months), and 2-year MFS was 29.7% (median, 10 months). Two-year OS (25%; median, 15.5 months) compared with our previous study on 5-fluorouracil-based CT-RT (2.8%) was significantly improved (p <0.001).

CONCLUSIONS

Gemcitabine CT-RT seems correlated with improved outcomes. Healthier patients who are likely to complete the treatment schedule may benefit most from this therapy.

Pancreatic cancer: advances in medical therapy

Progress in the treatment of pancreatic cancer has been notably slow and modest in contrast to other cancers of the GI tract over the last 5 years. Pancreatic cancer still continues to be a devastating illness that is marked by the appearance of early metastatic disease, despite curative surgery and the relative chemoresistance of the disease. However, small incremental benefits have been seen, and point to areas of research and development over the subsequent years. Developments in adjuvant chemotherapy and the use of gemcitabine in combination with other cytotoxic agents or with biological agents have changed clinical practice. Given its poor outlook and the paucity of active therapies, even modest gains can lead to regulatory approval and, therefore, pancreatic cancer represents a common target for pharmaceutical companies. Newer agents are in development with the promise of further refinement in treatment selection based on molecular tumor characteristics.

Borderline resectable pancreatic cancer: on the edge of survival

BACKGROUND

Patients with borderline resectable pancreatic cancer are at high risk of having positive surgical margins due to involvement of the tumor with adjacent vasculature. This article reviews the management of this subset of pancreatic cancer patients.

METHODS

The authors review the current definitions of borderline resectable pancreatic cancer and how it is diagnosed and staged. The history, current approaches, and future directions in neoadjuvant therapy for borderline resectable pancreatic cancer are also reviewed with emphasis on various chemotherapy regimens that have been used. The application of intensity-modulated radiation therapy and image-guided radiation therapy that accounts for respiratory motion to targeting the gross tumor volume in the pancreas are discussed, and the promise of integrating targeted therapies in neoadjuvant treatment programs is highlighted.

RESULTS

The use of neoadjuvant treatment programs that employ gemcitabine-based chemotherapy regimens followed by chemoradiation increases the likelihood of subsequent margin-negative resection in borderline resectable pancreatic cancer.

CONCLUSIONS

There has been progress in the imaging, staging, surgical technique, and the use of chemotherapy and chemoradiotherapy in the management of borderline resectable pancreatic cancer. Patients can benefit from multidisciplinary management at high-volume pancreatic cancer treatment centers.

Adjuvant therapy for pancreatic cancer: a review

Pancreatic cancer is uniformly fatal unless it can be surgically resected. Survival rates for the 15% to 20% of patients who have resectable disease, however, are a disappointing 10% to 30%, depending on the status of margins and surrounding lymph nodes. In the mid-1980s, a landmark study by the Gastrointestinal Tumor Study Group was the first to demonstrate a survival benefit from adjuvant therapy in the form of chemoradiation. Since then, several studies in both North America and Europe have tested the role of adjuvant chemotherapy or chemoradiation in pancreatic cancer, and the results have stirred great controversy. For this review, the evidence for adjuvant therapy in pancreatic cancer was examined, and the significant practice differences that exist between North American and European oncologists were highlighted. The authors investigated the results from the European Study Group for Pancreatic Cancer-1 trial and the reasons why that study has served to reinforce rather than resolve these trans-Atlantic differences. They also reviewed preliminary data from more recent adjuvant trials and explored the possible benefits of a neoadjuvant approach.

Neoadjuvant chemotherapy and radiation for patients with locally unresectable pancreatic adenocarcinoma: feasibility, efficacy, and survival

BACKGROUND

We evaluated the feasibility and efficacy of neoadjuvant chemotherapy and radiation for patients with locally unresectable pancreatic cancer.

MATERIALS AND METHODS

From October 2000 to August 2006, 245 patients with pancreatic adenocarcinoma underwent surgical exploration at our institution. Of these, 78 patients (32%) had undergone neoadjuvant therapy for initially unresectable disease, whereas the remaining patients (serving as the control group) were explored at presentation (n=167). All neoadjuvant patients received gemcitabine-based chemotherapy, often in conjunction with docetaxal and capecitabine in a regimen called GTX (81%). Seventy-five percent of neoadjuvant patients also received preoperative abdominal radiation (5,040 rad).

RESULTS

Neoadjuvant patients were younger than control-group patients (60.8 vs 66.2 years, respectively, p<0.002). Seventy-six percent of neoadjuvant patients were resected as compared to 83% of control patients (NS). Concomitant vascular resection was required in 76% of neoadjuvant patients but only 20% of NS (p<0.01). Complications were more frequent in the neoadjuvant group (44.1 vs 30.9%, p<0.05), and mortality was higher (10.2 vs 2.9%, p<0.03). Among the neoadjuvant patients, all but one of the deaths were in patients that underwent arterial reconstruction. Mortality for patients undergoing a standard pancreatectomy without vascular resection was 0.8% in this series. Of patients resected, negative margins were achieved in 84.7% of neoadjuvant patients and 72.7% of NS. Within the cohort of neoadjuvant patients, radiation significantly increased the complication rate (13.3 vs 54.6%, p<0.006), but did not affect median survival (512 vs 729 days, NS). Median survival for patients who received neoadjuvant therapy (503 days) was longer than NS that were found to be unresectable at surgery (192 days, p<0.001) and equivalent to NS that were resected (498 days).

CONCLUSIONS

Resection rate, margin status, and median survivals were equivalent when neoadjuvant patients were compared to patients considered resectable by traditional criteria, demonstrating equal efficacy. Surgical resection with venous reconstruction following neoadjuvant therapy for patients with locally advanced pancreatic cancer can be performed with acceptable morbidity and mortality. This approach extended the boundaries of surgical resection and greatly increased median survival for the "inoperable" patient with advanced pancreatic cancer.

Primary advanced unresectable pancreatic cancer

Median as well as overall survival of pancreatic cancer patients in the advanced stage is extremely low despite advances in cancer therapy regarding tumor cell biology, therapy resistance, and diagnosis. In matters of chemoradiation therapy (CRT) in locally advanced pancreatic cancer, favorable positive effect has been reached with different radiotherapy proceedings such as intraoperative radiation therapy with or without external chemo-/radiation therapy or with CRT alone with regard to local tumor pain, local tumor remission, or local control of disease and overall survival. Primary (chemo-) radiation therapy only rarely leads to local remission. Intraoperative radiation therapy (IORT) merely reaches pain palliation in most cases. By administering up-to-date primary CRT, especially with gemcitabine-associated CRT, local remission in up to 50% of patients can be observed. By applying neoadjuvant CRT, better resectability and the reduction of postoperative positive lymph node metastasis has been seen in patients with resectable or possibly resectable pancreatic cancer. With primary CRT, resectability can also be achieved in patients with primary unresectable pancreatic cancer. It has been shown at the evaluation of patients' progression samples--either treated with neoadjuvant or primarily with radiotherapy (with conventional radiation technique)--that the rate of local recurrence or local progression can be reduced in comparison with historical cohorts. By contrast, the rate on distant metastases was not affected. Whereas concurrent CRT leads to favorable local tumor control, this procedure has a minor effect as to the survival in most of the studies. Because metastases occur mostly out of the irradiation field and because of partly advanced local tumor progression, the concept of combined CRT with continuing chemotherapy was developed. Median survival of pancreatic patients in the advanced stage is approx. 3-5 months, with a 12-month survival probability of 10% despite advances in cancer therapy. On the other hand, the 5-year survival probability is 0.4%-3.0%. The causes of such a dismal prognosis can be understood first of all in the commonly late diagnosis, second in the aggressive tumor cell biology with continuing therapy resistance, and finally because an acceptable resection rate can be achieved only in specialized centers. Only 10%-15% of patients can be resected after the diagnosis of pancreatic cancer. Resection is considered a potential curative therapy. However, median survival of these patients amounts to only 13-18 months, with a 5-year survival of 10%-20%. The survival rate did not improve with a radical resection and extended lymphadenectomy. Furthermore, 15%-30% of primary nonmetastatic pancreatic cancer is unresectable due to extended vessel infiltration at time of diagnosis. The prognosis for these patients is very dismal due to lack of specific therapy; moreover, median overall survival is a maximum of 6-8 months.

Future chemoradiation strategies in pancreatic cancer

Although not universally accepted, 5-fluorouracil (5-FU)-based chemoradiation is considered a standard treatment for patients with localized pancreatic cancer. Randomized trials have indicated that chemoradiation improves median survival of both locally advanced and resected pancreatic cancer. While the use of adjuvant chemoradiation in pancreatic cancer has been called into question since the publication of the European Study Group for Pancreatic Cancer (ESPAC)-1 trial, this study has not changed standard practice in the United States. All randomized trials investigating adjuvant chemoradiation have reported significant local as well as distant disease control limitations, making the study of novel chemoradiation and adjuvant chemotherapy important. Selected centers are investigating neoadjuvant chemoradiation in radiographically resectable patients. Advantages of neoadjuvant chemoradiation compared to postoperative therapy include increased local control, increased access to therapy, addressing the systemic disease recurrence risk without delay, and optimal patient selection for pancreaticoduodenectomy through exclusion of patients with rapidly progressive metastatic disease. In the years since it was approved for use in pancreatic cancer, gemcitabine has stood the test of time as a systemic agent but has not been widely adopted as a radiosensitzer in pancreatic cancer. Single-arm clinical trials that initially explored gemcitabine as a radiosensitzer in locally advanced pancreatic cancer demonstrated the potential for significant toxicity without dramatic improvements in efficacy. Recent strategies for improving the efficacy of chemoradiation include improved chemoradiation sensitization through the concurrent incorporation of molecular targeted agents, and the use of new radiation technology such as intensity-modulated radiotherapy (IMRT) and stereotactic radiotherapy. Herein, we discuss the relative merits of strategies that seek to improve outcome through these novel means and present recent data from novel strategies that will provide the background for future trials.

Neoadjuvant therapy in pancreatic cancer

Pancreatic cancer is the fourth leading cause of cancer deaths in the United States. Surgical resection offers the only hope of cure, though the addition of chemoradiation in the adjuvant setting has been shown to improve survival over surgery alone. Many patients are unable to receive adjuvant therapy due to prolonged postoperative recovery. For this reason, administration of chemoradiation preoperatively (neoadjuvant) has been proposed as an alternative to postoperative treatment. In patients with resectable disease, neoadjuvant therapy results in similar survivals compared to postoperative therapy, with a greater proportion of patients able to complete treatment. For selected patients with borderline or unresectable disease, neoadjuvant therapy offers the potential for tumor downstaging and increasing the likelihood of a margin-negative resection. This article reviews the use of neoadjuvant therapy in the treatment of pancreatic cancer.

Dosimetric Feasibility of Hypofractionated Proton Radiotherapy for Neoadjuvant Pancreatic Cancer Treatment

PURPOSE

To evaluate tumor and normal tissue dosimetry of a 5 cobalt gray equivalent (CGE) x 5 fraction proton radiotherapy schedule, before initiating a clinical trial of neoadjuvant, short-course proton radiotherapy for pancreatic adenocarcinoma.

METHODS AND MATERIALS

The first 9 pancreatic cancer patients treated with neoadjuvant intensity-modulated radiotherapy (1.8 Gy x 28) at the Massachusetts General Hospital had treatment plans generated using a 5 CGE x 5 fraction proton regimen. To facilitate dosimetric comparisons, clinical target volumes and normal tissue volumes were held constant. Plans were optimized for target volume coverage and normal tissue sparing.

RESULTS

Hypofractionated proton and conventionally fractionated intensity-modulated radiotherapy plans both provided acceptable target volume coverage and dose homogeneity. Improved dose conformality provided by the hypofractionated proton regimen resulted in significant sparing of kidneys, liver, and small bowel, evidenced by significant reductions in the mean doses, expressed as percentage prescribed dose, to these structures. Kidney and liver sparing was most evident in low-dose regions (< or =20% prescribed dose for both kidneys and < or =60% prescribed dose for liver). Improvements in small-bowel dosimetry were observed in high- and low-dose regions. Mean stomach and duodenum doses, expressed as percentage prescribed dose, were similar for the two techniques.

CONCLUSIONS

A proton radiotherapy schedule consisting of 5 fractions of 5 CGE as part of neoadjuvant therapy for adenocarcinoma of the pancreas seems dosimetrically feasible, providing excellent target volume coverage, dose homogeneity, and normal tissue sparing. Hypofractionated proton radiotherapy in this setting merits Phase I clinical trial investigation.

[The role of neoadjuvant chemoradiation in pancreatic cancer]

Although complete surgical resection, when possible, leads to prolonged survival in pancreatic cancer, if used alone, its results remain sub-optimal. Neoadjuvant strategies are recent in pancreatic cancer: in primary resectable tumors, they ensure that all patients obtain additional treatment to complete surgery; in locally advanced tumors, they allow a better selection of candidates for curative resection. By delaying surgery, neoadjuvant strategies modify the initial diagnostic process and the symptomatic treatment of pancreatic cancer. Several recent phase I-II studies have confirmed the feasibility and efficacy of the association of chemotherapy and radiotherapy, which is well-tolerated and is associated with better local control and survival. Due to the aggressiveness of pancreatic cancers, most recent cytotoxic agents should be associated with modern radiation techniques. Neoadjuvant chemoradiation is under evaluation in pancreatic cancers, and no randomized phase III trials comparing neoadjuvant and adjuvant therapeutic sequences has been reported. Moreover, radiological and pathological evaluations, not only at diagnosis, but also after preoperative chemoradiation, must be standardized to improve the selection of patients who will benefit from this multi-modal treatment.

Suppression of the malignant phenotype in pancreatic cancer by overexpression of phospholipid hydroperoxide glutathione peroxidase

Phospholipid glutathione peroxidase (PhGPx) reduces lipid hydroperoxides generated in biomembranes and also uses a wide range of reducing cofactors in addition to glutathione. PhGPx is synthesized as a mitochondrial PhGPx form (L-form) and as a nonmitochondrial PhGPx form (S-form). Our aims were to determine whether overexpression of PhGPx altered pancreatic tumor cell behavior. Pancreatic cancer cell lines were found by Western blotting to have diminished levels of PhGPx-immunoreactive protein compared with normal human pancreas. To normalize the levels of this protein, PhGPx was overexpressed in MIA PaCa-2 and AsPC-1 human pancreatic cancer cells by infection with an adenovirus-PhGPx L-form construct (AdPhGPx- L-form) (0-200 MOI) or with an adenovirus-PhGPx S-form construct (AdPhGPx-S-form) (0-200 MOI), and cell growth, plating efficiency, and growth in soft agar were determined. Pancreatic cancer cells were also injected subcutaneously into nude mice and tumor volume was calculated. Single direct injections of the adenoviral- PhGPx constructs were made into preestablished tumors. In vitro, AdPhGPx-S-form demonstrated 80% tumor growth inhibition, whereas AdPhGPx-L-form demonstrated 95% tumor growth inhibition. Ad- PhGPx-L-form or AdPhGPx-S-form also decreased plating efficiency and growth in soft agar. AdPhGPx-Lform decreased in vivo tumor growth to a greater extent than did AdPhGPx-S-form. Because of the growthinhibitory effects of PhGPx, lipid hydroperoxides may play an important role in the growth of pancreatic cancer.

Pancreaticoduodenectomy after Neoadjuvant Therapy in a Jehovah's Witness with Locally Advanced Pancreatic Cancer: Case Report and Approach to Avoid Transfusion

Although the morbidity and mortality rates associated with pancreaticoduodenectomy (PD) have been improving over the past several decades, perioperative transfusions are often needed. Here, we review the preoperative planning and overall management of a Jehovah's Witness patient with locally advanced pancreatic cancer who would not accept blood transfusion. Management of this case is reviewed, along with the relevant literature regarding major surgery in the Jehovah's Witness population. The use of neoadjuvant chemoradiation was used successfully in locally advanced disease, allowing surgical resection. In addition, we outline a cogent strategy using pre-, intra-, and postoperative techniques to minimize blood loss and maintain hemoglobin at acceptable levels thereby preventing the need for transfusion. These strategies, once in place, may be able to reduce transfusions in all patients having major resections for malignancy.