Long-term results of full-dose gemcitabine with radiation therapy compared to 5-fluorouracil with radiation therapy for locally advanced pancreas cancer

Treatment of primary or recurrent non-resectable pancreatic cancer with proton beam irradiation combined with gemcitabine-based chemotherapy

BACKGROUND

Pancreatic cancer accounts for around 4.6% of cancers deaths worldwide per year. Despite many advances in treatment regimes, the prognosis is still poor. Only 20% of tumors are primarily resectable. Recurrences-both with distant metastasis as well as locoregional-are frequent. For patients with primary nonresectable localized disease or localized recurrences, we offered chemoradiation to achieve local control over a long period of time. We here report our results on combined chemoradiation of pancreatic tumors and local recurrences using proton beam therapy.

MATERIALS AND METHODS

We report on 25 patients with localized nonresectable pancreatic cancer (15 patients) or local recurrent disease (10 patients). All patients were treated with combined proton radiochemotherapy. Overall survival, progression-free survival, local control, and treatment-related toxicity were analyzed using statistically methods.

RESULTS

Median RT dose was 54.0 Gy (RBE) for proton irradiation. The toxicity of treatment was acceptable. Four CTCAE grade III and IV adverse events (bone marrow disfunction, gastrointestinal [GI] disorders, stent dislocation, myocardial infarction) were recorded during or directly after the end of radiotherapy; two of them were related to combined chemoradiation (bone marrow disfunction, GI disorders). Six weeks after radiotherapy, one additional grade IV toxicity was reported (ileus, caused by peritoneal carcinomatosis, not treatment related). The median progression-free survival was 5.9 months and median overall survival was 11.0 months. The pretherapy CA19‑9 level was a statistically significant prognostic factor for enhanced overall survival. Local control at 6 months and 12 months were determined to be 86% and 80%, respectively.

CONCLUSION

Combined proton chemoradiation leads to high local control rates. Unfortunately, PFS and OS are driven by distant metastasis and were not improved compared to historical data and reports. With this in mind, enhanced chemotherapeutical regimes, in combination with local irradiation, should be evaluated.

Radiotherapy in Pancreatic Cancer: To Whom, When, and How?

The diagnosis rate of pancreatic cancer is steadily increasing. The average age of onset is close to 70 years. In most cases, the disease is diagnosed at an advanced stage. The indications for and techniques of radiotherapy are changing over time. The aim of this thesis is to present the role and possibilities of radiotherapy from the perspective of radiation oncologist. The most common cause of treatment failure in pancreatic cancer remains generalisation. The implementation of new systemic treatment regimens contributes to improved treatment outcomes regardless of the stage of the disease. With improved treatment outcomes in terms of the incidence of distant metastases, the impact of local curability on the length and quality of life of patients increases. Modern radiotherapy offers the opportunity to achieve high local cure rates. Postoperative radiotherapy in combination with chemotherapy seems justified in the group of postoperative pancreatic cancer patients with pT3 and pN+ features. In the group of patients with borderline resectable pancreatic cancer, the impact of radiotherapy in combination with the latest chemotherapy regimens is difficult to define clearly. In the setting of a diagnosis of advanced pancreatic cancer, radiotherapy, especially stereotactic radiotherapy, in combination with chemotherapy, contributes to improved local curability and allows to achieve a significantly reduced level of pain.

Comparison of acute gastrointestinal toxicities between 3-dimensional conformal radiotherapy and intensity-modulated radiotherapy including prophylactic regions in chemoradiotherapy with S-1 for pancreatic cancer-importance of dose volume histogram parameters in the stomach as the predictive factors

The purpose of this study was to compare acute gastrointestinal (GI) toxicities in patients who underwent 3-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiotherapy (IMRT) in chemoradiotherapy (CRT) with S-1 including prophylactic regions for pancreatic cancer. We also investigated the predictive factor of acute GI toxicities in dose volume histogram (DVH) parameters. Patients who received CRT with S-1 for pancreatic cancer between January 2014 and March 2021 were included. Radiotherapy (RT) with a total dose of 50-54 Gy was delivered. We examined the differences in the frequencies of acute GI toxicity of grade 2 or higher and DVH parameters of the stomach (ST) and duodenum (DU) between the 3DCRT group and the IMRT group. The RT-related predictive factors of acute GI toxicities were investigated by univariate and multivariate analyses. There were 25 patients in the 3DCRT group and 31 patients in the IMRT group. The frequencies of acute GI toxicity of G2 or higher were 36% in the 3DCRT group and 9.7% in the IMRT group (p = 0.035). ST V50 was the most predictive factor (p = 0.001), and the incidences of acute GI toxicity of G2 or higher in ST V50 ≥ 4.1 cc and < 4.1cc were 43.7% and 7.7%, respectively. ST V40 was also a significant predictive factor of acute GI toxicity (p = 0.002). IMRT could reduce acute GI toxicities in CRT with S-1 including prophylactic regions for pancreatic cancer. Acute GI toxicities may be affected by moderate to high doses to the ST.

Significance of lymphocyte recovery from treatment-related lymphopenia in locally advanced pancreatic cancer

BACKGROUND AND PURPOSE

Radiation-induced lymphopenia is associated with poor prognosis in resected pancreatic cancer and locally advanced pancreatic cancer. However, whether lymphocyte recovery contributes to pancreatic cancer prognosis has not been well-investigated.

MATERIALS AND METHODS

We evaluated 497 locally advanced pancreatic cancer patients who underwent concurrent chemoradiotherapy (CCRT). Complete blood counts of patients were obtained before, during, and after CCRT until the 12-month follow-up visit. Patients were categorized into 3 groups according to the development of and recovery from acutte severe lymphopenia (ASL): no ASL (group A, n = 198), recovery from ASL (group B, n = 141), and no recovery from ASL (group C, n = 89). Prognostic factors of overall survival (OS) and progression-free survival (PFS) were determined using Cox regression analyses.

RESULTS

In groups A, B, and C, the 2-year OS rates were 40.4%, 31.9%, and 14.6%, respectively, and the 2-year PFS rates were 23.7%, 18.4%, and 10.1%, respectively. OS and PFS were comparable between Groups A and B, while group C had poor OS and PFS (p < 0.001). Recovery from ASL was associated with superior OS (HR 0.42, 95% CI: 0.32-0.55, p < 0.001) and PFS (HR 0.53, 95% CI: 0.41-0.70, p < 0.001). The baseline lymphocyte counts and target volume independently predicted development and recovery from ASL.

CONCLUSION

Recovery from ASL was associated with both superior OS and PFS in patients who received CCRT for locally advanced pancreatic cancer. Baseline lymphocyte counts and target volume were associated with both the development of and recovery from treatment-related ASL.

White paper on pancreatic ductal adenocarcinoma from society of abdominal radiology's disease-focused panel for pancreatic ductal adenocarcinoma: Part I, AJCC staging system, NCCN guidelines, and borderline resectable disease

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive gastrointestinal malignancy with a poor 5-year survival rate. Accurate staging of PDAC is an important initial step in the development of a stage-specific treatment plan. Different staging systems/consensus statements convened by different societies and academic practices are currently used. The most recent version of the American Joint Committee on Cancer (AJCC) tumor/node/metastases (TNM) staging system for PDAC has shifted its focus from guiding management to assessing prognosis. In order to preoperatively define the resectability of PDAC and to guide management, additional classification systems have been developed. The National Comprehensive Cancer Network (NCCN) guidelines, one of the most commonly used systems, provide recommendations on the management and the determination of resectability for PDAC. The NCCN divides PDAC into three categories of resectability based on tumor-vessel relationship: 'resectable,' 'borderline resectable,' and 'unresectable'. Among these, the borderline disease category is of special interest given its evolution over time and the resulting variations in the definition and the associated recommendations for management between different societies. It is important to be familiar with the evolving criteria, and treatment and follow-up recommendations for PDAC. In this article, the most current AJCC staging (8th edition), NCCN guidelines (version 2.2019-April 9, 2019), and challenges and controversies in borderline resectable PDAC are reviewed.

Management of unresectable, locally advanced pancreatic adenocarcinoma

The diagnosis of unresectable locally advanced pancreatic adenocarcinoma (LAPC) requires confirmation, through imaging tests, of the unfeasibility of achieving a complete surgical resection, in the absence of metastatic spread. The increase in overall survival (OS), together with an appropriate symptom management is the therapeutic target in LAPC, maintaining an acceptable quality of life and, if possible, increasing the time until the appearance of metastasis. Chemoradiation (CRT) improves OS compared to best support treatment or radiotherapy (RT) but with greater toxicity. No significant increase in OS has been achieved with CRT when compared to chemotherapy (QT) alone in patients without disease progression after four months of treatment with QT. However, a significantly better local control, that is, a significant increase in the time to disease progression was associated with this approach. The greater effectiveness of the schemes FOLFIRINOX and gemcitabine (Gem) + Nab-paclitaxel compared to gemcitabine alone, has been extrapolated from metastatic disease to LAPC, representing a possible alternative for patients with good performance status (ECOG 0-1). In the absence of randomized clinical trials, Gem is the standard treatment in LAPC. If disease control is achieved after 4-6 cycles of QT, the use of CRT for consolidation can be considered an option vs QT treatment maintenance. Capecitabine has a better toxicity profile and effectiveness compared to gemcitabine as a radiosensitizer. After local progression, and without evidence of metastases, treatment with RT or CRT, in selected patients, can support to maintain the regional disease control.

Pancreatic adenocarcinoma response to chemotherapy enhanced with non-invasive radio frequency evaluated via an integrated experimental/computational approach

Although chemotherapy combined with radiofrequency exposure has shown promise in cancer treatment by coupling drug cytotoxicity with thermal ablation or thermally-induced cytotoxicity, limited access of the drug to tumor loci in hypo-vascularized lesions has hampered clinical application. We recently showed that high-intensity short-wave capacitively coupled radiofrequency (RF) electric-fields may reach inaccessible targets in vivo. This non-invasive RF combined with gemcitabine (Gem) chemotherapy enhanced drug uptake and effect in pancreatic adenocarcinoma (PDAC), notorious for having poor response and limited therapeutic options, but without inducing thermal injury. We hypothesize that the enhanced cytotoxicity derives from RF-facilitated drug transport in the tumor microenvironment. We propose an integrated experimental/computational approach to evaluate chemotherapeutic response combined with RF-induced phenotypic changes in tissue with impaired transport. Results show that RF facilitates diffusive transport in 3D cell cultures representing hypo-vascularized lesions, enhancing drug uptake and effect. Computational modeling evaluates drug vascular extravasation and diffusive transport as key RF-modulated parameters, with transport being dominant. Assessment of hypothetical schedules following current clinical protocol for Stage-IV PDAC suggests that unresponsive lesions may be growth-restrained when exposed to Gem plus RF. Comparison of these projections to experiments in vivo indicates that synergy may result from RF-induced cell phenotypic changes enhancing drug transport and cytotoxicity, thus providing a potential baseline for clinically-focused evaluation.

The significance of Trk receptors in pancreatic cancer

This study investigated the Trk receptor family as a therapeutic target in pancreatic ductal adenocarcinoma and assessed their prognostic significance. Global gene expression analysis was investigated in prospectively collected pancreatic ductal adenocarcinomas that had either undergone neoadjuvant chemoradiation or were treated by surgery. PANC-1 and MIA-PaCa-2 cell lines were investigated to establish whether fractionated radiation altered expression of four neuroendocrine genes and whether this resulted in subsequent changes in radiosensitivity. A specific inhibitor of TrkA, B, and C, AstraZeneca 1332, was investigated in vitro and in vivo in combination with radiation. A tissue microarray was constructed from 77 pancreatic ductal adenocarcinoma patients who had undergone neoadjuvant chemoradiation and the Trk receptor, and neurogenic differentiation 1 expression was assessed and correlated with overall survival. A total of 99 genes were identified that were differentially expressed in the chemoradiation patients with neuroendocrine genes and pathways, in particular the neurogenic differentiation 1 and Trk receptor family, being prominent. Fractionated radiation upregulated the expression of neuroendocrine genes, and AstraZeneca 1332 treatment in vitro enhanced radiosensitivity. No added effect of AstraZeneca 1332 was observed in vivo. Trk receptor expression varied between isoforms but did not correlate significantly with clinical outcome. Radiation treatment upregulated neuroendocrine gene expression but the Trk receptor family does not appear to be a promising treatment target.

A Comparison of Gastrointestinal Toxicities between Intensity-Modulated Radiotherapy and Three-Dimensional Conformal Radiotherapy for Pancreatic Cancer

Background/Aims

Concurrent chemoradiotherapy (CCRT) is considered the treatment option for locally advanced pancreatic cancer, but accompanying gastrointestinal toxicities are the most common complication. With the introduction of three-dimensional conformal radiotherapy (3-D CRT) and intensity-modulated radiotherapy (IMRT), CCRT-related adverse events are expected to diminish. Here, we evaluated the benefits of radiation modalities by comparing gastrointestinal toxicities between 3-D CRT and IMRT.

Methods

Patients who received CCRT between July 2010 and June 2012 in Severance Hospital, Yonsei University College of Medicine, were enrolled prospectively. The patients underwent upper endoscopy before and 1 month after CCRT.

Results

A total of 84 patients were enrolled during the study period. The radiotherapy modalities delivered included 3D-CRT (n=40) and IMRT (n=44). The median follow-up period from the start of CCRT was 10.6 months (range, 3.8 to 29.9 months). The symptoms of dyspepsia, nausea/vomiting, and diarrhea did not differ between the groups. Upper endoscopy revealed significantly more gastroduodenal ulcers in the 3-D CRT group (p=0.003). The modality of radiotherapy (3D-CRT; odds ratio [OR], 11.67; p=0.011) and tumor location (body of pancreas; OR, 11.06; p=0.009) were risk factors for gastrointestinal toxicities.

Conclusions

IMRT is associated with significantly fewer gastroduodenal injuries among patients treated with CCRT for pancreatic cancer.

Comparative evaluation of respiratory-gated and ungated FDG-PET for target volume definition in radiotherapy treatment planning for pancreatic cancer

OBJECTIVE

The purpose of this study was to evaluate the usefulness of respiratory-gated positron emission tomography (4D-PET) in pancreatic cancer radiotherapy treatment planning (RTTP).

MATERIALS AND METHODS

Fourteen patients with 18F-fluorodeoxyglucose (FDG)-avid pancreatic tumours were evaluated between December 2013 and March 2015. Two sets of volumes were contoured for the pancreatic tumour of each patient. The biological target volume in three-dimensional RTTP (BTV3D) was contoured using conventional respiratory un-gated PET. The BTV3D was then expanded using population-based margins to generate a series of internal target volume 3D (ITV3D) values. The ITV 4D (ITV4D) was contoured using 4D-PET. Each of the five phases of 4D-PET was used for 4D contouring, and the ITV4D was constructed by summing the volumes defined on the five individual 4D-PET images. The relative volumes and normalized volumetric overlap were computed between ITV3D and ITV4D.

RESULTS

On average, the FDG-avid tumour volumes were 1.6 (range: 0.8-2.3) fold greater in the ITV4D than in the BTV3D. On average, the ITV3D values were 2.0 (range: 1.1-3.4) fold larger than the corresponding ITV4D values.

CONCLUSION

The ITV generated from 4D-PET can be used to improve the accuracy or reduce normal tissue irradiation compared with conventional un-gated PET-based ITV.

Hypofractionated Conformal Radiotherapy with Concurrent Full-Dose Gemcitabine Versus Standard Fractionation Radiotherapy with Concurrent Fluorouracil for Unresectable Pancreatic Cancer: a Multi-Institution Experience

PURPOSE/OBJECTIVE(S)

The purpose of this study was to compare oncologic outcomes and toxicity profile of hypofractionated conformal radiotherapy (RT) with concurrent full-dose gemcitabine versus standard fractionation RT with concurrent 5-fluorouracil (5-FU) in the treatment of unresectable non-metastatic pancreatic cancer.

MATERIALS/METHODS

Patients with unresectable non-metastatic adenocarcinoma of the pancreas treated at three institutions were included. All patients were treated with chemoradiotherapy (CRT) consisting of either hypofractionated RT to the gross disease concurrent with a full-dose gemcitabine-based regimen versus standard fractionation RT to the tumor and elective nodes concurrent with 5-FU. End points included rates of gastrointestinal (GI) toxicities, overall survival (OS), and distant metastasis free survival (DMFS).

RESULTS

From January 1999 to December 2009, 170 patients were identified (118 RT/gemcitabine, 52 RT/5-FU). There were no differences in demographic or clinical factors. Acute GI toxicities (grades <3 versus ≥3) were 82.2 and 17.8 %, respectively, for patients treated with RT/gemcitabine and 78.9 and 21.2 % for those treated with RT/5-FU (p = 0.67). Late GI toxicities (grades <3 versus ≥3) were 88.1 and 11.9 %, respectively, for RT/gemcitabine and 80.8 and 19.2 % for RT/5-FU (p = 0.23). OS for RT/gemcitabine and RT/5-FU were 52 versus 36 % at 1 year and 14 versus 6 % at 2 years favoring the RT/gemcitabine group (p = 0.02). DMFS at 1 and 2 years for RT/gemcitabine were 41 and 11 % versus 24 and 4 % for RT/5-FU (p = 0.02).

CONCLUSIONS

RT/gemcitabine was equivalent in toxicity to RT/5-FU but was associated with superior OS and DMFS. When RT is used in the treatment of unresectable pancreatic cancer, hypofractionated conformal RT with concurrent full-dose gemcitabine may be the preferred approach.

Locally Advanced, Unresectable Pancreatic Cancer: American Society of Clinical Oncology Clinical Practice Guideline

PURPOSE

To provide evidence-based recommendations to oncologists and others for treatment of patients with locally advanced, unresectable pancreatic cancer.

METHODS

American Society of Clinical Oncology convened an Expert Panel of medical oncology, radiation oncology, surgical oncology, gastroenterology, palliative care, and advocacy experts and conducted a systematic review of the literature from January 2002 to June 2015. Outcomes included overall survival, disease-free survival, progression-free survival, and adverse events.

RESULTS

Twenty-six randomized controlled trials met the systematic review criteria.

RECOMMENDATIONS

A multiphase computed tomography scan of the chest, abdomen, and pelvis should be performed. Baseline performance status and comorbidity profile should be evaluated. The goals of care, patient preferences, psychological status, support systems, and symptoms should guide decisions for treatments. A palliative care referral should occur at first visit. Initial systemic chemotherapy (6 months) with a combination regimen is recommended for most patients (for some patients radiation therapy may be offered up front) with Eastern Cooperative Oncology Group performance status 0 or 1 and a favorable comorbidity profile. There is no clear evidence to support one regimen over another. The gemcitabine-based combinations and treatments recommended in the metastatic setting (eg, fluorouracil, leucovorin, irinotecan, and oxaliplatin and gemcitabine plus nanoparticle albumin-bound paclitaxel) have not been evaluated in randomized controlled trials involving locally advanced, unresectable pancreatic cancer. If there is local disease progression after induction chemotherapy, without metastasis, then radiation therapy or stereotactic body radiotherapy may be offered also with an Eastern Cooperative Oncology Group performance status ≤ 2 and an adequate comorbidity profile. If there is stable disease after 6 months of induction chemotherapy but unacceptable toxicities, radiation therapy may be offered as an alternative. Patients with disease progression should be offered treatment per the ASCO Metastatic Pancreatic Cancer Treatment Guideline. Follow-up visits every 3 to 4 months are recommended. Additional information is available at www.asco.org/guidelines/LAPC and www.asco.org/guidelines/MetPC and www.asco.org/guidelineswiki.

Localized Pancreatic Cancer: Multidisciplinary Management

Pancreatic cancer is an aggressive cancer that continues to have single-digit 5-year mortality rates despite advancements in the field. Surgery remains the only curative treatment; however, most patients present with late-stage disease deemed unresectable, either due to extensive local vascular involvement or the presence of distant metastasis. Resection guidelines that include a borderline resectable group, as well as advancements in neoadjuvant chemotherapy and radiation that improve resectability of locally advanced disease, may improve outcomes for patients with more invasive disease. Multi-agent chemotherapy regimens fluorouracil, leucovorin, irinotecan, and oxaliplatin (FOLFIRINOX) and nab-paclitaxel with gemcitabine improved response rates and survival in metastatic pancreatic cancer and are now being used in earlier stages for patients with localized potentially resectable and unresectable disease, with goals of downstaging tumors to allow margin-negative resection and reducing systemic recurrence. Chemoradiotherapy, although still controversial for both resectable and unresectable pancreatic cancer, is being used in the context of contemporary chemotherapy backbone regimens, and novel radiation techniques such as stereotactic body frame radiation therapy (SBRT) are studied on the premise of maintaining or improving efficacy and reducing treatment duration. Patient selection for optimal treatment designation is currently provided by multidisciplinary tumor boards, but biomarker discovery, in blood, tumors, or through novel imaging, is an area of intense research. Results to date suggest that some patients with unresectable disease at the outset have survival rates as good as those with initially resectable disease if able to undergo surgical resection. Long-term follow-up and improved clinical trials options are needed to determine optimal treatment modalities for patients with localized pancreatic cancer.

Neoadjuvant multimodal treatment of pancreatic ductal adenocarcinoma

Treatment of pancreatic ductal adenocarcinoma (PDAC) is increasingly multidisciplinary, with neoadjuvant strategies (chemotherapy, radiation, and surgery) administered in patients with resectable, borderline resectable, or locally advanced disease. The rational supporting this management is the achievement of both higher margin-negative resections and conversion rates into potentially resectable disease and in vivo assessment of novel therapeutics. International guidelines suggest an initial staging of the disease followed by a multidisciplinary approach, even considering the lack of a treatment approach to be considered as standard in this setting. This review will focus on both literature data supporting these guidelines and on new opportunities related to current more active chemotherapy regimens. An analysis of the pathological assessment of response to therapy and the potential role of target therapies and translational biomarkers and ongoing clinical trials of significance will be discussed.

Concurrent radiotherapy with oral fluoropyrimidine versus gemcitabine in locally advanced pancreatic cancer: a systematic review and meta-analysis

Background

Gemcitabine (GEM) is the most widely utilized systemic agent in combination with radiation therapy (RT) for treating locally advanced pancreatic cancer (LAPC) in the concurrent setting. Despite recent interest in using two novel oral fluoropyrimidines (FUs), capecitabine and S-1, in this setting, there is a lack of randomized controlled trials (RCTs) to support this approach.

Methods

Trials published between 1994 and 2014 were identified by an electronic search of public databases (Medline, Embase, and the Cochrane Library). All prospective studies were independently identified by two authors for inclusion. Demographic data, treatment response, objective response rate (ORR), progression-free and overall survival (PFS and OS, respectively), and toxicities were extracted and analyzed using comprehensive meta-analysis software (version 2.0).

Results

Twenty-three cohorts with 843 patients were included: 497 patients were treated with GEM and 346 patients were treated with oral FU. Pooled OS was significantly higher at 1 and 2 years for S-1 plus RT than for GEM plus RT (relative risk [RR] 1.27; 95% confidence interval [CI], 1.00–1.65; P=0.03; and RR 1.75; 95% CI, 1.18–2.60, P=0.002, respectively), while 1-year PFS and ORR were not significantly different between S-1 and GEM-based chemoradiotherapy (P=0.37 and P=0.06, respectively). Additionally, comparable efficacy was found between capecitabine and GEM-based chemoradiotherapy in terms of OS, PFS, and ORR. As for grade 3 and 4 acute toxicity, oral FU plus RT significantly reduced the risk of developing hematologic toxicities, nausea, and vomiting when compared to GEM plus RT (P<0.001).

Conclusions

Oral FU plus RT may be a safe and feasible regimen for patients with LAPC, with similar efficacy and low rate of toxicities compared with GEM plus RT. Our findings support the need to compare S-1 with GEM in the concurrent setting in large prospective RCTs due to its potential survival benefits.

Intensity modulated radiation therapy reduces gastrointestinal toxicity in locally advanced pancreas cancer

PURPOSE

We compared gastrointestinal (GI) and hematologic toxicity in patients with locally advanced pancreas cancer (LAPC) undergoing definitive chemoradiation using intensity modulated radiation therapy (IMRT) or 3-dimensional conformal radiation therapy (3D-CRT) planning.

METHODS AND MATERIALS

We retrospectively studied 205 patients with LAPC undergoing IMRT (n = 134) and 3D-CRT (n = 71) between May 2003 and March 2012. Patient, tumor, and treatment characteristics and acute GI/hematology toxicity according to the Common Terminology Criteria for Adverse Events, version 3.0, were recorded. Multivariable logistic regression models were used to test association between acute grade 2+ GI and hematologic toxicity outcomes and predictors. Propensity score analysis for grade 2+ GI toxicity was performed to reduce bias for confounding variables: age, gender, radiation dose, field size, and chemotherapy type.

RESULTS

Median follow-up time for survivors was 22 months and was similar between groups. Median RT dose was significantly higher for IMRT versus 3D-CRT (5600 cGy vs 5040 cGy, P < .001); concurrent chemotherapy was mainly gemcitabine (56%) or 5-fluorouracil (38%). Grade 2+ GI toxicity occurred in 34% (n = 24) of 3D-CRT compared with 16% (n = 21) of IMRT patients. Using propensity score analysis, 3D-CRT had significantly higher grade 2+ GI toxicity (odds ratio, 1.26; 95% confidence interval, 1.08-1.45; P = .001). Grade 2+ hematologic toxicity was similar between IMRT and 3D-CRT groups, but was significantly greater in recipients of concurrent gemcitabine than in 5-fluorouracil (62% vs 29%, P < .0001).

CONCLUSIONS

IMRT is associated with significant lower grade 2+ GI toxicity versus 3D-CRT for patients undergoing definitive chemoradiation therapy for LAPC. Because IMRT is better tolerated at higher doses and may allow further dose escalation, potentially improving local control for this aggressive disease. Further prospective studies of dose-escalated chemoradiation using IMRT are warranted.

Definitive Chemoradiation With Full-dose Gemcitabine for Unresectable Pancreatic Cancer: Efficacy of Involved-Field Radiotherapy

OBJECTIVES

Definitive chemoradiotherapy for unresectable pancreatic cancer has traditionally involved 5-fluorouracil-based chemotherapy. Our institution has a long history of combining gemcitabine and radiotherapy (RT), and performed a retrospective review of all patients treated in this manner.

MATERIALS AND METHODS

We reviewed the records of 180 patients treated from 1999 to 2012. Mean RT dose was 40.9 Gy in 2.2-Gy fractions, and targeted only radiographically apparent disease. Ninety-six percent of patients received full-dose gemcitabine-based chemotherapy with RT. Kaplan-Meier was used to analyze time-to-event endpoints, and Cox regression models were used to assess significant prognostic variables.

RESULTS

Eighty-nine percent of patients completed RT without a toxicity-related treatment break. Median follow-up was 10.2 months. Twenty-nine percent of patients had a radiographic decrease in primary tumor size following treatment. Median overall survival was 11.8 months, time to distant metastasis (TDM) was 6.7 months, and time to local recurrence (TLR) was 8.3 months. On multivariate analysis, male sex, lower performance status, and higher posttreatment CA 19-9 level predicted for worse overall survival. Posttreatment, CA 19-9 was also associated with TDM and TLR, and radiographic tumor response was associated with better TLR.

CONCLUSION

Definitive chemoradiation using full-dose gemcitabine is well tolerated and achieves survival outcomes comparable to reported trials in the literature.

Modeling Combined Chemotherapy and Particle Therapy for Locally Advanced Pancreatic Cancer

Pancreatic ductal adenocarcinoma is the only cancer for which deaths are predicted to increase in 2014 and beyond. Combined radiochemotherapy protocols using gemcitabine and hypofractionated X-rays are ongoing in several clinical trials. Recent results indicate that charged particle therapy substantially increases local control of resectable and unresectable pancreas cancer, as predicted from previous radiobiology studies considering the high tumor hypoxia. Combination with chemotherapy improves the overall survival (OS). We compared published data on X-ray and charged particle clinical results with or without adjuvant chemotherapy calculating the biological effective dose. We show that chemoradiotherapy with protons or carbon ions results in 1 year OS significantly higher than those obtained with other treatment schedules. Further hypofractionation using charged particles may result in improved local control and survival. A comparative clinical trial using the standard X-ray scheme vs. the best current standard with carbon ions is crucial and may open new opportunities for this deadly disease.

Neoadjuvant gemcitabine, docetaxel, and capecitabine followed by gemcitabine and capecitabine/radiation therapy and surgery in locally advanced, unresectable pancreatic adenocarcinoma

BACKGROUND

This prospective study was undertaken to assess toxicity, resectability, and survival in pancreatic adenocarcinoma patients presenting with locally advanced, unresectable disease treated with neoadjuvant gemcitabine, docetaxel, and capecitabine (GTX) and gemcitabine and capecitabine (GX)/radiation therapy (RT).

METHODS

All patients presenting to the Pancreas Center were evaluated for eligibility. Forty-five patients (mean age, 64 years; range, 44-83 years)-34 patients deemed unresectable because of arterial involvement and 11 patients deemed unresectable because of extensive venous involvement-were treated with 6 cycles of GTX. Those with arterial involvement were treated with GX/RT after chemotherapy.

RESULTS

The GTX and GX/RT treatments were tolerated with the expected drug-related toxicities. There were no bowel perforations, cases of pancreatitis, or delayed strictures. Among those with arterial involvement, 29 underwent subsequent resection, with 20 (69%) achieving R0 resections. All 11 patients with venous-only involvement underwent resection, with 8 achieving R0 resections and 3 achieving complete pathologic responses. For the arterial arm, the 1-year survival rate was 71% (24 of 34 patients), and the median survival was 29 months (95% confidence interval, 21-38 months). Thirteen patients (38%) have not relapsed (range, 5-49+ months). For the venous arm, the median survival has not been reached at more than 42 months. Six patients (55%) in the venous arm did not experience recurrence (range, 6.2-42+ months).

CONCLUSIONS

GTX plus GX/RT is an effective neoadjuvant regimen that can be safely administered to patients up to at least the age of 83 years. It is associated with a high response rate, a high rate of R0 resections, and prolonged overall survival.

Histopathological effects of preoperative chemoradiotherapy for pancreatic cancer: an analysis for the impact of radiation and gemcitabine doses

BACKGROUND AND PURPOSE

Histopathological findings of patients who underwent resection for pancreatic adenocarcinoma (PC) after preoperative chemoradiotherapy (CRT) reportedly showed beneficial effects. The purpose of our study was to evaluate the correlation between histopathological effects (HE) of preoperative CRT and treatment parameters [radiation and gemcitabine (GEM) doses].

MATERIAL AND METHODS

HE of CRT were assessed on 158 primary lesions of 157 patients with PC who underwent pancreatic resection after preoperative CRT with GEM between January 2006 and December 2011. The radiation dose delivered to the primary tumor site and surrounding regional nodal areas was 50 Gy until September 2009 followed by the dose escalation of a 10 Gy boost added for delivery with the field-in-field technique to the roots of the celiac and superior mesenteric arteries. Intravenous administration of GEM (1000 /m(2)) was initiated concurrently on days 1, 8, and 15, every 4 weeks and generally repeated for 3 cycles. HE of CRT on the primary tumor were categorized based on the number of tumor cells destroyed.

RESULTS

The median overall survival time was 74.5 months and 3-year and 5-year survival rates were 64.3% and 54.5%, respectively. Dose-volume parameters of radiation such as D33 with a cut-off value of 51.6 Gy were correlated significantly with HE (p=.0230). Lesions having received GEM>7625 mg/m(2) before surgical resection more frequently showed positive HE (p=.0002). Multivariate logistic regression analysis demonstrated that both D33 and cumulative GEM dose were significant predictors of definite HE (p=.0110 and <.0001, respectively).

CONCLUSIONS

Our retrospective analysis showed that dose intensity of radiation and GEM is significantly related to HE of preoperative CRT for PC.

Management options in locally advanced pancreatic cancer

Pancreatic ductal adenocarcinoma is a highly lethal cancer that is rarely curable at the time of presentation. Unfortunately, most patients are diagnosed with either metastatic or locally advanced disease, which is not amenable to surgery owing to the high likelihood of incomplete resection. Given the generally poor prognosis with propensity for metastatic failure greater than that for local failure, treatment options are variable, and include chemotherapy, radiotherapy, targeted therapies, and combinations thereof. This review summarizes the current evidence for definitive management of locally advanced pancreatic adenocarcinoma, as well as the role of palliative therapies. Future directions, including the development of predictive biomarkers and novel systemic agents, are also discussed.

Locally advanced pancreatic cancer: the role of definitive chemoradiotherapy

At the time of diagnosis, around 20% of patients with pancreatic cancer present at a resectable stage, 50% have metastatic disease and 30% have locally advanced tumour, non-metastatic but unresectable because of superior mesenteric artery or coeliac encasement. Despite advances in chemoradiotherapy and improved systemic chemotherapeutic agents, patients with locally advanced pancreatic cancer suffer from high rates of distant metastatic failure and from local progression, with a median survival time ranging from 5 to 11 months. In the past 30 years, modest improvements in median survival have been attained for these patients treated by chemoradiotherapy or chemotherapy protocols. The optimal therapy for patients with locally advanced pancreatic carcinoma remains controversial. This review aims to evaluate the role of radiotherapy for these patients.

Full-Dose Gemcitabine Is a More Effective Chemotherapeutic Agent Than 5-Fluorouracil for Concurrent Chemoradiotherapy as First-Line Treatment in Locally Advanced Pancreatic Cancer

<b><i>Objectives:</i></b> To compare the efficacy of full-dose gemcitabine-based concurrent chemoradiotherapy (FG-CCRT) and conventional 5-fluorouracil CCRT (5FU-CCRT) for locally advanced pancreatic cancer (LAPC). <b><i>Methods:</i></b> 109 LAPC cases treated with FG-CCRT (n = 89) or 5FU-CCRT (n = 20) were reviewed retrospectively. The FG-CCRT group was composed of a full-dose gemcitabine monotherapy (1,000 mg/m²) arm and a combination therapy with cisplatin (70 mg/m²) arm. The 5FU-CCRT group used a radiosensitizing dose of 5-FU (500 mg/m²) plus leucovorin (20 mg/m²). Concurrent radiotherapy was targeted at the tumor with a 5-mm margin without lymph node irradiation. <b><i>Results:</i></b> Objective response rate (ORR) and disease control rate (DCR) was significantly higher in the FG-CCRT group (ORR: 32.6 vs. 5%, p = 0.013; DCR: 79.8 vs. 50.0%, p = 0.006). FG-CCRT showed remarkable superiority to 5FU-CCRT for suppressing distant metastasis (18.0 vs. 45.0%, p = 0.017). Neutropenia (34.8 vs. 10%, p = 0.032) and thrombocytopenia (21.3 vs. 0.0%, p = 0.021) were more frequent in the FG-CCRT group as originally expected. When dividing the FG-CCRT group to gemcitabine monotherapy (GEM) and gemcitabine plus cisplatin, toxicities of the GEM subgroup were not different than those of the 5FU-CCRT group. <b><i>Conclusion:</i></b> FG-CCRT, especially full-dose gemcitabine monotherapy-based CCRT was more effective for the initial control of LAPC than 5FU-CCRT, and also relatively safe.

Dosimetric and clinical predictors of toxicity following combined chemotherapy and moderately hypofractionated rotational radiotherapy of locally advanced pancreatic adenocarcinoma

BACKGROUND AND PURPOSE

Hypofractionated radiotherapy (RT) of pancreatic adenocarcinoma is limited by the tolerance of adjacent normal tissues. A better understanding of the influence of dosimetric variables on the rate of toxicity after RT must be considered an important goal.

METHODS AND MATERIALS

Sixty-one patients with histologically proven locally advanced disease (LAPD) were analyzed. The therapeutic strategy consisted of induction chemotherapy (ChT) followed by concurrent chemoradiotherapy (CRT). In 39 out of 61 patients the target volume was based on a four-dimensional CT (4D-CT) procedure. Delivered dose was 44.25Gy in 15 fractions to PTV2, which consisted of pancreatic tumor and regional lymph nodes considered radiologically involved; 23 out of 61 patients received a simultaneous integrated boost (SIB) to a tumor sub-volume infiltrating the great abdominal vessels (PTV1) with dose in the range of 48-58Gy. RT was delivered with Helical Tomotherapy. Dose-volume histograms (DVHs) of target volumes and organs at risk (OARs) were collected for analysis. The predictive value of clinical/dosimetric parameters was tested by univariate/multivariate analyses.

RESULTS

The crude incidence of acute gastrointestinal (GI) grade 2 toxicity was 33%. The 12-month actuarial rate of "anatomical" (gastro-duodenal mucosa damage) toxicity was 13% (95% CI: 4-22%). On univariate analysis, several stomach and duodenum DVH endpoints are predictive of toxicity after moderately hypofractionated radiotherapy. Multivariate analysis confirmed that baseline performance status and the stomach V20[%] were strong independent predictors of acute GI grade ⩾2 toxicity. The high-dose region of duodenum DVH (V45[%]; V40[%]) was strongly correlated with grade ⩾2 "anatomical" toxicity; the best V40[%] and V45[%] cut-off values were 16% and 2.6% respectively.

CONCLUSION

Regarding dosimetric indices, stomach V20[%] correlates with a higher rate of acute toxicity; more severe acute and late anatomical toxicities are related to the high dose region of duodenum DVH.

Chemoradiation in patients with isolated recurrent pancreatic cancer - therapeutical efficacy and probability of re-resection

Background

In the present retrospective analysis we analysed the therapeutic outcome of a set of patients, who were treated with chemoradiation (CRT) for recurrent pancreatic cancer (RPC) in a single institution.

Patients and Methods

Forty-one patients had a history of primary resection for pancreatic cancer. In case of an unresectable recurrency patients were treated with CRT at our institution between 2002 and 2010 with a median dose of 48.4 Gy (range 39.6–54 Gy). Concurrent chemotherapy regimes included Gemcitabine (GEM) in 37/41 patients (90%) and Fluorouracil (FU) or Capecitabine (CAP) in 4/41 patients (10%). Patients were re-evaluated after CRT with computed tomography and/or explorative laparotomy. During re-resection or laparotomy 15 patients received an additional intraoperative radiotherapy (IORT) with a median dose of 15 Gy (range 12–15 Gy). Median age was 65 years (range 39–76 years) and there were 26 male and 15 female patients.

Results

The median overall survival (mOS), local control (LC) and progression-free survival (PFS) were 16.1, 13.8 and 6.9 months respectively for all patients after the first day of CRT. Re-resection was possible in five patients (12%) and a complete remission (CR) as defined by tumor-free biopsy was seen in 6 patients (15%). When re-resection could be achieved after CRT mOS was improved to 28.3 months (n = 5 patients, 95%-CI 10.2 – 46.3 months). Patients receiving IORT had a significantly improved mOS compared to no IORT (p = 0.034). Fifteen patients (37%) experienced a local tumour progression and main site of distant metastasis was the liver (11 patients, 27%).Overall treatment-related toxicity was mild, grade III hematologic toxicity was observed in 11 patients (27%).

Conclusion

In summary we observed a good therapeutic response with mild to moderate toxicity levels for CRT in RPC. Overall survival and PFS were clearly improved in case of induction of a complete remission (tumor-free biopsies) or after achieving a re-resection, thus providing a curative intended therapy even in case of disease recurrence.

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

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

Dose-volume analysis of predictors for gastrointestinal toxicity after concurrent full-dose gemcitabine and radiotherapy for locally advanced pancreatic adenocarcinoma

PURPOSE

To identify dosimetric predictors for the development of gastrointestinal (GI) toxicity in patients with locally advanced pancreatic adenocarcinoma (LAPC) treated with concurrent full-dose gemcitabine and radiotherapy (GemRT).

METHODS AND MATERIALS

From June 2002 to June 2009, 46 LAPC patients treated with definitive GemRT were retrospectively analyzed. The stomach and duodenum were retrospectively contoured separately to determine their dose-volume histogram (DVH) parameters. GI toxicity was defined as Grade 3 or higher GI toxicity. The follow-up time was calculated from the start of RT to the date of death or last contact. Univariate analysis (UVA) and multivariate analysis (MVA) using Kaplan-Meier and Cox regression models were performed to identify risk factors associated with GI toxicity. The receiver operating characteristic curve and the area under the receiver operating characteristic curve (AUC) were used to determine the best DVH parameter to predict for GI toxicity.

RESULTS

Of the patients, 28 (61%) received concurrent gemcitabine alone, and 18 (39%) had concurrent gemcitabine with daily erlotinib. On UVA, only the V(20Gy) to V(35Gy) of duodenum were significantly associated with GI toxicity (all p ≤ 0.05). On MVA, the V(25Gy) of duodenum and the use of erlotinib were independent risk factors for GI toxicity (p = 0.006 and 0.02, respectively). For the entire cohort, the V(25Gy) of duodenum is the best predictor for GI toxicity (AUC = 0.717), and the 12-month GI toxicity rate was 8% vs. 48% for V(25Gy) ≤ 45% and V(25Gy) > 45%, respectively (p = 0.03). However, excluding the erlotinib group, the V(35Gy) is the best predictor (AUC = 0.725), and the 12-month GI toxicity rate was 0% vs. 41% for V(35Gy) ≤ 20% and V(35Gy) > 20%, respectively (p = 0.04).

CONCLUSIONS

DVH parameters of duodenum may predict Grade 3 GI toxicity after GemRT for LAPC. Concurrent use of erlotinib during GemRT may increase GI toxicity.