Addition of radiotherapy to adjuvant chemotherapy is associated with improved overall survival in resected pancreatic adenocarcinoma: An analysis of the National Cancer Data Base

Recent Developments in the Treatment of Pancreatic Cancer

Pancreatic duct adenocarcinoma is currently the sixth-leading cause of cancer death worldwide and the fourth in Europe, with a continuous increase in annual lethality in Portugal during the last two decades. Surgical en-bloc resection of the tumor with microscopic-negative margins and an adequate lymphadenectomy is the only possibility of long-term survival. As this type of cancer is a systemic disease, there is a high rate of recurrence even after curative resection, turning systemic therapy the core of its management, mostly based on chemotherapy. Neoadjuvant strategies for nonmetastatic disease showed significant improvement in overall survival compared with upfront surgery, namely in borderline resectable disease. Moreover, these strategies provided downstaging in several situations allowing R0 resections. Under these new oncologic strategies, several recent surgical issues were introduced, namely more aggressive vascular resections and even tumor resections in oligometastatic disease. This review revisits the state-of-the-art of surgical and oncological interventions in pancreatic duct adenocarcinoma and highlights recent advances in the field aiming to achieve higher survival rates.

Additional adjuvant radiotherapy improves survival at 1 year after surgical treatment for pancreatic cancer patients with T4, N2 disease, positive resection margin, and receiving adjuvant chemotherapy

Background

While adjuvant chemotherapy has been established as standard practice following radical resection of pancreatic ductal adenocarcinoma (PDAC), the role of adjuvant radiation therapy (RT) and which patients may benefit remains unclear.

Methods

This retrospective study included PDAC patients who received pancreatic surgery from April 2012 to December 2019 in Zhongshan Hospital Fudan University. Patients with carcinoma in situ, distant metastasis, and without adjuvant chemotherapy were excluded. Cox proportional hazards modeling of survival were constructed to find potential prognostic factors. Propensity score matching (PSM) and exploratory subgroup analyses were used to create a balanced covariate distribution between groups and to investigate therapeutic effect of radiotherapy in certain subgroups.

Results

A total of 399 patients were finally included, 93 of them receiving adjuvant chemoradiotherapy (C+R+) and 306 of them receiving chemotherapy only. Patients in C+R+ group were more likely to be male patients with T3-4 disease. Lymph node metastases was the only negative prognostic factor associated with overall survival (OS). Additional adjuvant RT was not associated with an OS benefit both before and after PSM. Surprisingly, a trend towards improved OS with RT among patients with either T4, N2 disease or R1 resection becomes significant in patients alive more than 1 year after surgery.

Conclusion

Adjuvant RT was not associated with an OS benefit across all patients, though did show a possible OS benefit for the subgroup with T4N2 disease or R1 resection at 1 year after surgery.

Deep Learning for Fully Automated Prediction of Overall Survival in Patients Undergoing Resection for Pancreatic Cancer: A Retrospective Multicenter Study

OBJECTIVE

To develop an imaging-derived biomarker for prediction of overall survival (OS) of pancreatic cancer by analyzing preoperative multiphase contrast-enhanced computed topography (CECT) using deep learning.

BACKGROUND

Exploiting prognostic biomarkers for guiding neoadjuvant and adjuvant treatment decisions may potentially improve outcomes in patients with resectable pancreatic cancer.

METHODS

This multicenter, retrospective study included 1516 patients with resected pancreatic ductal adenocarcinoma (PDAC) from 5 centers located in China. The discovery cohort (n=763), which included preoperative multiphase CECT scans and OS data from 2 centers, was used to construct a fully automated imaging-derived prognostic biomarker-DeepCT-PDAC-by training scalable deep segmentation and prognostic models (via self-learning) to comprehensively model the tumor-anatomy spatial relations and their appearance dynamics in multiphase CECT for OS prediction. The marker was independently tested using internal (n=574) and external validation cohorts (n=179, 3 centers) to evaluate its performance, robustness, and clinical usefulness.

RESULTS

Preoperatively, DeepCT-PDAC was the strongest predictor of OS in both internal and external validation cohorts [hazard ratio (HR) for high versus low risk 2.03, 95% confidence interval (CI): 1.50-2.75; HR: 2.47, CI: 1.35-4.53] in a multivariable analysis. Postoperatively, DeepCT-PDAC remained significant in both cohorts (HR: 2.49, CI: 1.89-3.28; HR: 2.15, CI: 1.14-4.05) after adjustment for potential confounders. For margin-negative patients, adjuvant chemoradiotherapy was associated with improved OS in the subgroup with DeepCT-PDAC low risk (HR: 0.35, CI: 0.19-0.64), but did not affect OS in the subgroup with high risk.

CONCLUSIONS

Deep learning-based CT imaging-derived biomarker enabled the objective and unbiased OS prediction for patients with resectable PDAC. This marker is applicable across hospitals, imaging protocols, and treatments, and has the potential to tailor neoadjuvant and adjuvant treatments at the individual level.

The Current Role of Radiation in Pancreatic Cancer and Future Directions

Survival outcomes for localized pancreatic adenocarcinoma remains poor. Multimodality therapeutic regimens are critical to maximizing survival outcomes for these patients, which includes the use of systemic therapy, surgery, and radiation. In this review, the evolution of radiation techniques are discussed with a focus on modern techniques such as intensity modulated radiation and stereotactic body radiation therapy. However, the current role of radiation within the most common clinical scenarios for pancreatic cancer in the neoadjuvant, definitive, and adjuvant settings continues to be highly debated. The role of radiation in these settings is reviewed in the context of historical and modern clinical studies. In addition, emerging concepts including dose-escalated radiation, magnetic resonance-guided radiation therapy, and particle therapy are discussed to promote an understanding of how such concepts may change the role of radiation in the future.

Adjuvant therapy for margin positive pancreatic cancer: A propensity score matched analysis

BACKGROUND

Adjuvant chemotherapy or chemoradiation is often recommended for resected pancreatic adenocarcinoma. We sought to examine the impact of these therapies on R1 resected pancreatic cancer.

METHODS

Utilizing the National Cancer Database we identified patients who underwent pancreatic resection for adenocarcinoma. Patients were stratified by resection status and adjuvant therapy.

RESULTS

We identified 28,440 patients who underwent pancreatic resection. Patients with tumor size >2 cm were more likely to undergo R1 resections, p < 0.001. Adjuvant therapy improved survival in all patients with median and 5-year survival: adjuvant chemotherapy (21.7 months, 17.45%), chemoradiation (23.3 months, 20.9%) vs no adjuvant therapy (19.5 months, 19.1%), p < 0.001. In the R1 resection cohort survival was also improved with adjuvant therapy with chemoradiation demonstrating the most significant improvement: adjuvant chemotherapy (15.9 months, 6.5%), chemoradiation (18.7 months, 11.2%) vs no adjuvant therapy (12.5 months, 8.7%), p < 0.001. Chemoradiation but not adjuvant chemotherapy improved survival in the R1 node negative, p < 0.004, and node positive, p < 0.001. Adjuvant chemotherapy benefited survival in R1 node positive patients, p < 0.001.

CONCLUSIONS

Patients with pancreatic cancer who undergo R1 resection have significant improvement in survival when treated with adjuvant chemoradiation and adjuvant chemotherapy. However, benefits were greater in those receiving adjuvant chemoradiation.

Neoadjuvant Treatment Lowers the Risk of Mesopancreatic Fat Infiltration and Local Recurrence in Patients with Pancreatic Cancer

Simple Summary

After the implementation of an in-depth histopathological pancreas protocol, curative resection rates for pancreatic head cancers have drastically dropped. Standardized extended resections using embryo-anatomic landmarks (MPE), have recently been prooved to increase margin-negative resection rates. The mesopancreatic fat, excised during these extended resections, was infiltrated in the majority of the patients. Neoadjuvant treatment is an emerging topic of interest for pancreatic cancer patients. It remains unclear if these extended resections are still warranted in patients after neoadjuvant treatment. Neoadjuvant treatment lowered the risk for mesopancreatic fat infiltration and patients were less prone to local recurrence and margin positive resections when compared to patients after upfront surgery. However, the majority of the patients are yet diagnosed with mesopancreatic fat infiltration, justifying this extended approach synergistically with the treatment strategies for colorectal cancer.

Abstract

Background: Survival following surgical treatment of ductal adenocarcinoma of the pancreas (PDAC) remains poor. The recent implementation of the circumferential resection margin (CRM) into standard histopathological evaluation lead to a significant reduction in R0 rates. Mesopancreatic fat infiltration is present in ~80% of PDAC patients at the time of primary surgery and recently, mesopancreatic excision (MPE) was correlated to complete resection. To attain an even higher rate of R0(CRM−) resections in the future, neoadjuvant therapy in patients with a progressive disease seems a promising tool. We analyzed radiographic and histopathological treatment response and mesopancreatic tumor infiltration in patients who received neoadjuvant therapy prior to MPE. The aim of our study was to evaluate the need for MPE following neoadjuvant therapy and if multi-detector computed tomographically (MDCT) evaluated treatment response correlates with mesopancreatic (MP) infiltration. Method: Radiographic, clinicopathological and survival parameters of 27 consecutive patients who underwent neoadjuvant therapy prior to MPE were evaluated. The mesopancreatic fat tissue was histopathologically analyzed and the 1 mm-rule (CRM) was applied. Results: In the study collective, both the rate of R0 resection R0(CRM−) and the rate of mesopancreatic fat infiltration was 62.9%. Patients with MP infiltration showed a lower tumor response. Surgical resection status was dependent on MP infiltration and tumor response status. Patients with MDCT-predicted tumor response were less prone to MP infiltration. When compared to patients after upfront surgery, MP infiltration and local recurrence rate was significantly lower after neoadjuvant treatment. Conclusion: MPE remains warranted after neoadjuvant therapy. Mesopancreatic fat invasion was still evident in the majority of our patients following neoadjuvant treatment. MDCT-predicted tumor response did not exclude mesopancreatic fat infiltration.

Optimal Adjuvant Treatment Approach After Upfront Resection of Pancreatic Cancer: Revisiting the Role of Radiation Based on Pathologic Features

OBJECTIVE

To identify the survival benefit of different adjuvant approaches and factors influencing their efficacy after upfront resection of pancreatic ductal adenocarcinoma (PDAC).

SUMMARY BACKGROUND DATA

The optimal adjuvant approach for PDAC remains controversial.

METHODS

Patients from the National Cancer Database who underwent upfront PDAC resection from 2010 to 2014 were analyzed to determine clinical outcomes of different adjuvant treatment approaches, stratified according to pathologic characteristics. Factors associated with overall survival were identified with multivariable logistic regression and Cox proportional hazards were used to compare overall survival of different treatment approaches in the whole cohort, and propensity score matched groups.

RESULTS

We included 16,709 patients who underwent upfront resection of PDAC. On multivariable analysis, tumor size, grade, positive margin, nodal involvement, lymphovascular invasion (LVI), stage, lymph node ratio, not receiving chemotherapy, and/or radiation were predictors for worse survival. In the presence of at least 1 high-risk pathologic feature (nodal or margin involvement or LVI) chemotherapy with subsequent radiation provided the most significant survival benefit (median survivals: 24.8 vs 21.0 mo for adjuvant chemotherapy; HR = 0.81; 95% CI: 0.77-0.86; P < 0.001 in propensity score matching). The addition of radiation to adjuvant chemotherapy did not significantly improve overall survival in those with no high-risk pathologic features (median survivals: 54.6 vs 42.7 mo for adjuvant chemotherapy; HR=0.90; 95% CI: 0.75-1.08; P = 0.25 in propensity score matching).

CONCLUSIONS

In the presence of any high-risk pathologic features (nodal or margin involvement or LVI), adjuvant chemotherapy followed by radiation provides a better survival advantage over chemotherapy alone after upfront resection of PDAC.

Current and emerging therapeutic strategies in pancreatic cancer: Challenges and opportunities

Pancreatic carcinoma (PC) is one of the leading causes of cancer-related deaths worldwide. Despite early detection and advances in therapeutics, the prognosis remains dismal. The outcome and therapeutic approach are dependent on the stage of PC at the time of diagnosis. The standard of care is surgery, followed by adjuvant chemotherapy. The advent of newer drugs has changed the landscape of adjuvant therapy. Moreover, recent trials have highlighted the role of neoadjuvant therapy and chemoradiotherapy for resectable and borderline resectable PC. As we progress towards a better understanding of tumor biology, genetics, and microenvironment, novel therapeutic strategies and targeted agents are now on the horizon. We have described the current and emerging therapeutic strategies in PC.

Prognostic Factors and Effect of Adjuvant Chemoradiation Following Chemotherapy in Resected Pancreatic Cancer Patients With Lymph Node Metastasis or R1 Resection

Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease with a poor prognosis. In resectable PDAC, the recurrence rate is still high even when surgery and adjuvant chemotherapy (CT) are applied. Regional lymph node metastasis and positive margins are associated with higher recurrence risk and worse survival. Adjuvant radiotherapy has been explored, but its efficacy remains controversial. In recent years, some characteristics have been reported to stratify patients who may benefit from adjuvant chemoradiation (CRT), such as lymph node metastasis and margin status. Adjuvant chemotherapy followed by chemoradiation (CT-CRT) was also proposed. A total of 266 patients with resectable PDAC who have lymph node metastasis or R1 resection after surgery were enrolled. In multivariate Cox regression analyses, pancreatic body or tail tumor location (HR 0.433, p<0.0001, compared with pancreatic head) and adjuvant CT predicted a better survival, while there were no significant differences among the different CT regimens. Higher T stage indicated poor survival (stage I: reference; stage II: HR 2.178, p=0.014; stage III: HR 3.581, p=0.001). Propensity score matching was applied in 122 patients to explore the role of CRT. A cohort of 51 patients (31 and 20 patients in the CT and CT-CRT groups, respectively) was generated by matching. Further analyses revealed adjuvant CT-CRT was associated with prolonged survival compared with CT alone (HR 0.284, p=0.014) and less frequent local recurrences (56.5% vs. 21.4% in the CT and CT-CRT group, respectively). However, no significant differences in disease-free survival among these two groups were observed.

Korean clinical practice guideline for pancreatic cancer 2021: A summary of evidence-based, multi-disciplinary diagnostic and therapeutic approaches

Pancreatic cancer is the eighth most common cancer and the fifth most common cause of cancer-related death in Korea. To enable standardization of management and facilitate improvements in outcome, a total of 53 multi-disciplinary experts in gastroenterology, surgery, medical oncology, radiation oncology, radiology, nuclear medicine, and pathology in Korea developed new recommendations that integrate the most up-to-date, evidence-based research findings and expert opinions. Recommendations were made on imaging diagnosis, endoscopic management, surgery, radiotherapy, palliative chemotherapy, and specific management procedures, including neoadjuvant treatment or adjuvant treatment for patients with resectable, borderline resectable, and locally advanced unresectable pancreatic cancer. This is the English version of the Korean clinical practice guideline for pancreatic cancer 2021. This guideline includes 20 clinical questions and 32 statements. This guideline represents the most standard guideline for the diagnosis and treatment of patients with pancreatic ductal adenocarcinoma in adults at this time in Korea. The authors believe that this guideline will provide useful and informative advice.

Adjuvant Treatment in Pancreatic Cancer: Shaping the Future of the Curative Setting

Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease even in the early stages, despite progresses in surgical and pharmacological treatment in recent years. High potential for metastases is the main cause of therapeutic failure in localized disease, highlighting the current limited knowledge of underlying pathological processes. However, nowadays research is focusing on the search for personalized approaches also in the adjuvant setting for PDAC, by implementing the use of biomarkers and investigating new therapeutic targets. In this context, the aim of this narrative review is to summarize the current treatment scenario and new potential therapeutic approaches in early stage PDAC, from both a preclinical and clinical point of view. Additionally, the review examines the role of target therapies in localized PDAC and the influence of neoadjuvant treatments on survival outcomes.

Impact of Adjuvant Chemoradiotherapy on Survival of Resected Pancreatic Adenocarcinoma Cancer: A Surveillance, Epidemiology and End Results (SEER) Analysis

Background

The benefits of postoperative adjuvant chemoradiotherapy (CRT) for pancreatic cancer remain controversial. The purpose of this study is to determine if adjuvant CRT can improve the overall survival of postoperative pancreatic cancer patients compared to adjuvant chemotherapy (CT).

Methods

Patients with resected pancreas adenocarcinoma were identified in the Surveillance, Epidemiology, and End Results (SEER) database (2004–2016). Multivariate Cox regression was used to determine the factors related to survival rate. Selection bias was reduced to a minimum through propensity matching analysis. Subgroup analyses by clinical characteristics were performed.

Results

This study identified 10,097 patients who received adjuvant CT (n = 5,454) or adjuvant CRT (n = 4,643). On multivariate analysis, age, sex, tumor size, site, grade, stage, T stage, and lymph node metastasis were independent risk factors for OS. The basic clinical characteristics were well balanced after propensity matching. After propensity matching, CRT can improve the survival rate compared with CT [median OS: 22 months vs 23 months (HR, 0.928; 95% CI, 0.881–0.977; P = 0.004)]. Subgroup analysis indicated that the survival benefit of adjuvant chemoradiotherapy was more significant in patients with female (HR, 0.860; 95% CI, 0.798–0.926; P = 0.005 for interaction) or T3 (HR, 0.905; 95% CI, 0.855–0.957; P = 0.04 for interaction) or lymph nodes positive (HR, 0.883; 95% CI, 0.832–0.938; P = 0.005 for interaction).

Conclusion

Adjuvant CRT was associated with improved survival compared with adjuvant CT in patients with resection of pancreatic ductal adenocarcinoma. The benefit was more significant in patients with female or T3 or lymph nodes positive.

Detailed Analysis of Margin Positivity and the Site of Local Recurrence After Pancreaticoduodenectomy

BACKGROUND

The association between a positive surgical margin and local recurrence after resection of pancreatic adenocarcinoma (PDAC) has been reported. Assessment of the location of the a positive margin and the specific site of local recurrence has not been well described.

METHODS

A prospectively maintained database was queried for patients who underwent R0/R1 pancreaticoduodenectomy for PDAC between 2000 and 2015. The pancreatic, posterior, gastric/duodenal, anterior peritoneal, and bile duct margins were routinely assessed. Postoperative imaging was reviewed for the site of first recurrence, and local recurrence was defined as recurrence located in the remnant pancreas, surgical bed, or retroperitoneal site outside the surgical bed.

RESULTS

During the study period, 891 patients underwent pancreaticoduodenectomy, and 390 patients had an initial local recurrence with or without distant metastases. The 5-year cumulative incidence of local recurrence by site included the remnant pancreas (4%; 95% confidence interval [CI], 3-5%), the surgical bed (35%; 95% CI, 32-39%), and other regional retroperitoneal site (4%; 95% CI, 3-6%). In the univariate analysis, positive posterior margin (hazard ratio [HR], 1.50; 95% CI, 1.17-1.91; p = 0.001) and positive lymph nodes (HR, 1.36; 95% CI, 1.06-1.75; p = 0.017) were associated with surgical bed recurrence, and in the multivariate analysis, positive posterior margin remained significant (HR, 1.40; 95% CI, 1.09-1.81; p = 0.009). An isolated local recurrence was found in 197 patients, and a positive posterior margin was associated with surgical bed recurrence in this subgroup (HR, 1.51; 95% CI, 1.08-2.10; p = 0.016).

CONCLUSION

In this study, the primary association between site of margin positivity and site of local recurrence was between the posterior margin and surgical bed recurrence. Given this association and the limited ability to modify this margin intraoperatively, preoperative assessment should be emphasized.

Adjuvant Pancreatic Cancer Management: Towards New Perspectives in 2021

Adjuvant chemotherapy is currently used in all patients with resected pancreatic cancer who are able to begin treatment within 3 months after surgery. Since the recent publication of the PRODIGE 24 trial results, modified FOLFIRINOX has become the standard-of-care in the non-Asian population with localized pancreatic adenocarcinoma following surgery. Nevertheless, there is still a risk of toxicity, and feasibility may be limited in heavily pre-treated patients. In more frail patients, gemcitabine-based chemotherapy remains a suitable option, for example gemcitabine or 5FU in monotherapy. In Asia, although S1-based chemotherapy is the standard of care it is not readily available outside Asia and data are lacking in non-Asiatic patients. In patients in whom resection is not initially possible, intensified schemes such as FOLFIRINOX or gemcitabine-nabpaclitaxel have been confirmed as options to enhance the response rate and resectability, promoting research in adjuvant therapy. In particular, should oncologists prescribe adjuvant treatment after a long sequence of chemotherapy +/- chemoradiotherapy and surgery? Should oncologists consider the response rate, the R0 resection rate alone, or the initial chemotherapy regimen? And finally, should they take into consideration the duration of the entire sequence, or the presence of limited toxicities of induction treatment? The aim of this review is to summarize adjuvant management of resected pancreatic cancer and to raise current and future concerns, especially the need for biomarkers and the best holistic care for patients.

The benefit of adjuvant radiotherapy on overall survival in resected stage I to II pancreatic cancer: A propensity-adjusted analysis

BACKGROUND

The survival time of patients with early pancreatic cancer (PC) is still disappointing, even after surgical resection. PC has an extremely poor prognosis. Herein, we aimed to investigate the survival effect of postoperative radiotherapy (PORT) on resected stage I to II PC.

MATERIAL AND METHODS

A large eligible sample of patients was identified from 2010 to 2015 from the Surveillance, Epidemiology, and End Results (SEER) registry. Survival analysis was conducted to evaluate the efficiency of PORT. Propensity score matching (PSM) analysis was used to reduce selection bias and to make the groups comparable.

RESULTS

A total of 3219 patients with resected stage I to II PC was included after rigid screening. The median overall survival (OS) was 26 months with PORT (n = 1055) versus 21 months with non-PORT (n = 2164) before matching (p<0.001). By multivariable analysis, PORT remained a favorable prognostic predictor for OS. In PSM analysis, receiving PORT was associated with improved OS (median, 26 months vs. 23 months; at 2 years, 51.7% vs. 46.7%; at 5 years, 23.3% vs. 17.4% (P = 0.006). After further meticulous exploration, only the stage IIB subgroup benefited from PORT (p<0.001). This result was due to the positive lymph node state (N+), whose mortality risk was cut by 23.4% (p<0.001) by PORT.

CONCLUSION

Addition of PORT to the treatment of patients with resected stage I to II PC conveys a survival benefit, particularly among those with N-positive or stage IIB disease.

Outcomes of Neoadjuvant Chemotherapy Versus Chemoradiation in Localized Pancreatic Cancer: A Case-Control Matched Analysis

BACKGROUND

Neoadjuvant therapy is increasingly used for patients with pancreatic ductal adenocarcinoma (PDAC). It is unknown whether neoadjuvant chemoradiotherapy is more effective than chemotherapy (NCRT vs. NAC). We aim to compare pathological and survival outcomes of NCRT and NAC in patients with PDAC.

PATIENTS AND METHODS

Single-center analysis of PDAC patients treated with NCRT or NAC followed by resection between December 2008 and December 2018 was performed. Average treatment effect (ATE) was estimated after case-control matching using Mahalanobis distance nearest-neighbor matching. Inverse probability weighted estimates (IPWE)-based ATE was estimated for disease-free survival (DFS) and overall survival (OS).

RESULTS

Among the 418 patients (mean age 66.8 years, 51% female) included in the study, 327 received NAC and 91 received NCRT. NCRT patients had higher rates of locally advanced disease, number of neoadjuvant chemotherapy cycles, more chemotherapy regimen crossover (gemcitabine and 5-FU based), and were more likely to undergo open surgical procedures and/or vascular resection (all p < 0.05). After matched analysis, NCRT was associated with a significant reduction in lymph node positive disease [ATE = (-)0.24, p = 0.007] and lymphovascular invasion [ATE = (-)0.20, p = 0.02]. While NCRT was associated with significantly improved DFS by 9.5 months (p = 0.006), it did not affect OS by IPWE-based ATE after adjusting for adjuvant therapy (ATE = 5.5 months; p = 0.32).

CONCLUSION

Compared with NAC alone, NCRT is associated with improved pathologic surrogates and disease-free survival, but not overall survival in patients with PDAC.

Evaluating the Impact of ESPAC-1 on Shifting the Paradigm of Pancreatic Cancer Treatment

BACKGROUND

In 2004, the European Study Group for Pancreatic Cancer (ESPAC)-1 long-term data concluded that adjuvant chemotherapy provided a survival benefit for patients with pancreatic ductal adenocarcinoma (PDAC), whereas adjuvant chemoradiation was associated with worse overall survival. In this study, we investigated how long it took for US practice patterns to change following this trial.

METHODS

The National Cancer Database was used to identify patients with stage I-III PDAC who underwent R0 or R1 resection followed by adjuvant chemotherapy or chemoradiation between 1998 and 2015. A multivariate analysis was performed to determine predictors of receiving adjuvant chemoradiation in the post-ESPAC-1 era.

RESULTS

Between 1998 and 2015, adjuvant chemotherapy use increased from 2.9% to 51.6%, whereas adjuvant chemoradiation decreased from 49.5% to 22.9%. In 2010, adjuvant chemotherapy utilization surpassed that of chemoradiation. For patients diagnosed in the post-ESPAC-1 era, adjuvant chemotherapy (n = 7733) and chemoradiation (n = 6969) groups were compared. Patients who underwent adjuvant chemoradiation were younger, had private insurance, underwent surgery at nonacademic centers, and had more pathologically advanced cancers (all P < 0.01). After 2010, R1 resection was the strongest independent predictor of adjuvant chemoradiation use by multivariate analysis (OR 2.05, CI 1.8-2.3, P < 0.01).

CONCLUSIONS

Adjuvant chemotherapy use exceeded that of adjuvant chemoradiation 6 y after the final publication of ESPAC-1 in 2004, highlighting the challenges of disseminating and adopting clinical data. After 2010, R1 disease was the most significant predictor of receiving adjuvant chemoradiation. Prospective studies are underway to definitively address the role of adjuvant chemoradiation in PDAC.

Comparison of efficacy between adjuvant chemotherapy and chemoradiation therapy for pancreatic cancer: AJCC stage-based approach

BACKGROUND

The adjuvant treatment for patients with resected pancreatic cancer (PC) is not yet standardized. Because the prognosis differs according to the American Joint Committee on Cancer (AJCC) stage, a tailored approach to establish more aggressive treatment plans in high-risk patients is necessary. However, studies comparing the efficacy of adjuvant treatment modalities according to the AJCC stage are largely lacking.

AIM

To compare the efficacy of chemotherapy and chemoradiation therapy according to AJCC 8th staging system in patients with PC who underwent surgical resection.

METHODS

A total of 335 patients who underwent surgical resection and adjuvant treatment for PC were included. Patients were divided into three groups: Chemoradiation therapy (CRT) group, systemic chemotherapy (SCT) group and combined treatment of chemoradiation plus chemotherapy therapy (CRT-SCT) group. The primary outcomes were differences in overall survival (OS) between the three groups. The secondary outcomes were differences in recurrence-free survival, recurrence pattern and adverse events between the three groups.

RESULTS

Patients received CRT (n = 65), SCT (n = 62) and CRT-SCT (n = 208). Overall median OS was 33.3 mo (95% confidence interval (CI): 27.4-38.6). In patients with stage I/II, the median OS was 27.0 mo (95%CI: 2.06-89.6) in the CRT group, 35.8 mo (95%CI: 26.9-NA) in the SCT group and 38.6 mo (95%CI: 33.3-55.7) in the CRT-SCT group. Among them, there was no significant difference in OS between the three groups. In 59 patients with stage III, median OS in the SCT group [19.0 mo (95%CI: 12.6-NA)] and the CRT-SCT group [23.4 mo (95%CI: 22.0-44.4)] was significantly longer than that in the CRT group [17.7 mo (95%CI: 6.8-NA); P = 0.011 and P < 0.001, respectively]. There were no significant differences in incidence of locoregional and distant recurrences between the three groups (P = 0.158 and P = 0.205, respectively). Incidences of grade 3 or higher hematologic adverse events were higher in the SCT and CRT-SCT groups than in the CRT group.

CONCLUSION

SCT and CRT-SCT showed significantly longer OS and recurrence-free survival than CRT in patients with AJCC stage III, while there was no significant difference in OS between the CRT, SCT and CRT-SCT groups in patients with AJCC stage I/II. Different adjuvant therapy according to AJCC stage can be applied in patients with PC.

Multidisciplinary standards of care and recent progress in pancreatic ductal adenocarcinoma

Despite tremendous gains in the molecular understanding of exocrine pancreatic cancer, the prognosis for this disease remains very poor, largely because of delayed disease detection and limited effectiveness of systemic therapies. Both incidence rates and mortality rates for pancreatic cancer have increased during the past decade, in contrast to most other solid tumor types. Recent improvements in multimodality care have substantially improved overall survival, local control, and metastasis-free survival for patients who have localized tumors that are amenable to surgical resection. The widening gap in prognosis between patients with resectable and unresectable or metastatic disease reinforces the importance of detecting pancreatic cancer sooner to improve outcomes. Furthermore, the developing use of therapies that target tumor-specific molecular vulnerabilities may offer improved disease control for patients with advanced disease. Finally, the substantial morbidity associated with pancreatic cancer, including wasting, fatigue, and pain, remains an under-addressed component of this disease, which powerfully affects quality of life and limits tolerance to aggressive therapies. In this article, the authors review the current multidisciplinary standards of care in pancreatic cancer with a focus on emerging concepts in pancreatic cancer detection, precision therapy, and survivorship.

Survival benefit of adjuvant chemoradiotherapy for positive or close resection margin after curative resection of pancreatic adenocarcinoma

BACKGROUND

This study was conducted to identify patients who may benefit from adjuvant chemoradiotherapy (CRT) for positive or close resection margin (RM) after curative resection of pancreatic adenocarcinoma.

METHODS

From 2004 to 2015, total of 472 patients with pancreatic adenocarcinoma underwent curative resection. After excluding patients with RM > 2 mm or unknown, remaining 217 patients were retrospectively analyzed. Forty-six (21.2%) patients were treated with adjuvant chemotherapy alone (CTx; mainly gemcitabine-based), 142 (65.4%) with adjuvant CRT (mainly upfront), and 29 (13.4%) patients didn't receive any adjuvant therapy (noTx group).

RESULTS

Locoregional recurrence rate was significantly lower in the CRT group (43.7%) than in the CTx group (71.7%) or noTx group (65.5%) (p = 0.001). Significant survival benefits of CRT over CTx (HR 0.602, p = 0.020 for overall survival (OS); HR 0.599, p = 0.016 for time to any recurrence (TTR)) were demonstrated in multivariate analysis. CRT group had more 5-year survivors than other groups. In the subgroup analysis, such benefits of adjuvant CRT over CTx was observed only in patients with head tumor & vascular RM > 0.5 mm, but not in patients with body/tail tumor or vascular RM ≤ 0.5 mm. In the CRT group, radiation dose≥54 Gy was significantly associated with better TTR and OS.

CONCLUSIONS

Adjuvant CRT could improve TTR and OS compared to adjuvant CTx alone in patients with close RM under 2 mm. Radiation dose escalation may be beneficial when feasible. Modern CRT regimen-based randomized evidence is needed for these high-risk patients.

Pancreatic Ductal Adenocarcinoma and Its Variants: Pearls and Perils

Pancreatic ductal adenocarcinoma (PDAC), an epithelial neoplasm derived from the pancreatic ductal tree, is the most common histologic type of pancreatic cancer and accounts for 85%-95% of all solid pancreatic tumors. As a highly lethal malignancy, it is the seventh leading cause of cancer death worldwide and is responsible for more than 300 000 deaths per year. PDAC is highly resistant to current therapies, affording patients a 5-year overall survival rate of only 7.2%. It is characterized histologically by its highly desmoplastic stroma embedding tubular and ductlike structures. On images, it typically manifests as a poorly defined hypoenhancing mass, causing ductal obstruction and vascular involvement. Little is known about the other histologic subtypes of PDAC, mainly because of their rarity and lack of specific patterns of disease manifestation. According to the World Health Organization, these variants include adenosquamous carcinoma, colloid carcinoma, hepatoid carcinoma, medullary carcinoma, signet ring cell carcinoma, undifferentiated carcinoma with osteoclast-like giant cells, and undifferentiated carcinoma. Depending on the subtype, they can confer a better or even worse prognosis than that of conventional PDAC. Thus, awareness of the existence and differentiation of these variants on the basis of imaging and histopathologic characteristics is crucial to guide clinical decision making for optimal treatment and patient management.

Patterns of Care and Outcomes of Adjuvant Chemoradiation for Node-Positive Pancreatic Adenocarcinoma

PURPOSE

The literature has been conflicting on the superiority of adjuvant chemoradiation over chemotherapy for node-positive adenocarcinoma of the pancreas following definitive surgery. We aimed to evaluate the patterns of care and outcomes of these two treatment options using the National Cancer Database (NCDB).

METHODS

Patients diagnosed with non-metastatic, node-positive adenocarcinoma of the pancreas from 2006 to 2014 who received oncologic resection with negative margins were identified in the NCDB. Patient- and clinical-related factors were compared between those who received adjuvant chemotherapy alone (aC) versus adjuvant chemoradiation (aCRT). Univariable and multivariable logistic regression was performed to assess for predictors of adjuvant chemoradiation use. The Kaplan-Meier method was used to assess overall survival (OS) and Cox regression analysis was used to assess impact of covariables on OS.

RESULTS

There were 3609 patients who met the study criteria, of which 2988 (82.8%) received chemotherapy alone and 621 (17.2%) who received chemoradiation. Median follow up for living patients was 33.8 months (IQR 22-51). On multivariable logistic regression, those who received treatment in more recent years of diagnoses (OR 0.21-0.37, p < 0.001) were less likely to receive aCRT over aC. Two-year OS for those who received chemo alone was 44.9% and for chemoradiation was 42.6% (p = 0.169). This finding was sustained on multivariable survival analysis (HR 0.99, p = 0.867).

CONCLUSIONS

Adjuvant chemotherapy alone for adenocarcinoma of the pancreas is the predominant treatment of choice among US hospitals. There was no overall survival benefit noted in those who were treated with adjuvant chemoradiation.

Adjuvant treatment of pancreatic cancer

PURPOSE OF REVIEW

Pancreatic cancer will soon become one of the most common causes of cancer death. Early detection of pancreatic cancer remains impossible and only 20% of patients are suitable for surgery once diagnosed. Even in this specific subgroup of patients, and despite improvements in surgery, overall survival remains poor, with an 80% recurrence rate. Consequently, many attempts have been made to prevent recurrence by adding chemotherapy, radiotherapy, or both.

RECENT FINDINGS

Here, we will focus on results of randomized trials evaluating the role of different postoperative treatments. Over 15 years ago, a trial demonstrated that chemoradiotherapy has a deleterious effect on survival. The same trial recommended adjuvant chemotherapy with fluorouracil as standard of care. Subsequent trials sought to identify better chemotherapy regimens. Two recently published trials evaluated the role of combination therapies for resected pancreatic cancer and demonstrated better outcomes with a gemcitabine and capecitabine combination and a fluorouracil, oxaliplatin, and irinotecan combination (FOLFIRINOX) versus gemcitabine alone.

SUMMARY

Results from recent trials suggest that FOLFIRINOX should be considered standard of care for fit patients.

A microRNA-based signature predicts local-regional failure and overall survival after pancreatic cancer resection

Resectable pancreatic adenocarcinoma (PC) is generally managed with surgery followed by chemotherapy, but the role of postoperative chemoradiation (pCRT) is controversial. We sought to identify a microRNA (miRNA) expression profile associated with higher risk for local-regional recurrence (LRR), which might help identify patients that may benefit from pCRT. Total RNA was isolated from viable tumor from 88 patients who underwent PC resection with or without chemotherapy, but did not receive radiation. Digital miRNA expression profiling was performed and risk scores were calculated based on the expression levels of the four most significantly correlated miRNAs, and dichotomized about the median to detect correlations between risk group, LRR and overall survival (OS). Two cohorts from The Cancer Genome Atlas (TCGA) and Seoul National University (SNU) were used for validation. Patients with high-risk scores had significantly worse LRR (p = 0.001) and worse OS (p = 0.034). Two-year OS rates for the high- and low-risk groups were 27.7% and 52.2%, respectively. On multivariable analysis, the risk score remained significantly associated with LRR (p = 0.018). When validated on TCGA data, a high-risk score was associated with worse OS on univariate (p = 0.03) and multivariable analysis (p = 0.017). When validated on the SNU cohort, a high-risk score was likewise associated with worse OS (p = 0.042). We have developed a 4-miRNA molecular signature that is associated with risk of LRR and OS after PC resection and validated on two separate cohorts. This signature has the potential to select patients most likely to benefit from pCRT, and should be tested further.

Metabolism of pancreatic cancer: paving the way to better anticancer strategies

Pancreatic cancer is currently one of the most lethal diseases. In recent years, increasing evidence has shown that reprogrammed metabolism may play a critical role in the carcinogenesis, progression, treatment and prognosis of pancreatic cancer. Affected by internal or external factors, pancreatic cancer cells adopt extensively distinct metabolic processes to meet their demand for growth. Rewired glucose, amino acid and lipid metabolism and metabolic crosstalk within the tumor microenvironment contribute to unlimited pancreatic tumor progression. In addition, the metabolic reprogramming involved in pancreatic cancer resistance is also closely related to chemotherapy, radiotherapy and immunotherapy, and results in a poor prognosis. Reflective of the key role of metabolism, the number of preclinical and clinical trials about metabolism-targeted therapies for pancreatic cancer is increasing. The poor prognosis of pancreatic cancer patients might be largely improved after employing therapies that regulate metabolism. Thus, investigations of metabolism not only benefit the understanding of carcinogenesis and cancer progression but also provide new insights for treatments against pancreatic cancer.

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

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

Is There a Standard Adjuvant Therapy for Resected Pancreatic Cancer?

Surgical resection remains the only treatment that offers a potential chance of long-term survival. Unfortunately, about 80% of patients treated with curative intent will develop recurrence. Since 2001, adjuvant therapy with gemcitabine or 5-fluorouracyle was recommended. This approach allows a median overall survival (OS) of around 23 months, and 5-year survival of 22%. In recent years, two phase-3 trials investigating new chemotherapy regimens resulted in considerably improved survival times. The doublet gemcitabine-capecitabine has shown improvement in OS from 25.5 to 28 months (p = 0.032) compared to gemcitabine, in the ESPAC-4 trial. Later, preliminary results of PRODIGE 24 trial presented at the 2018 ASCO meeting showed a superiority of a combination chemotherapy regimen with fluorouracil, leucovorin, irinotecan, and oxaliplatin (mFOLFIRINOX) when compared to gemcitabine alone, both in terms of median disease-free survival (21.6 vs. 12.8 months, p < 0.0001) and OS (54.4 vs. 35 months, p = 0.003). Contrary to chemotherapy, the role of adjuvant radiotherapy is still controversial, even in the case of R1 surgery. A randomized trial exploring the role of chemoradiotherapy in this setting is now ongoing in the US (RTOG-0848). Overall, the management of localized pancreatic adenocarcinoma is evolving. In this review, we summarize the current status and the most up-to-date developments in adjuvant treatment.

Adjuvant chemotherapy versus chemoradiation in high-risk pancreatic adenocarcinoma: A propensity score-matched analysis

PURPOSE

The American Society of Clinical Oncology guidelines recommend adjuvant chemoradiation (ACR) for margin-positive (R1) and/or node-positive (N+) pancreatic cancers. Our goal was to investigate if there is evidence of superiority of adjuvant chemoradiation (ACR) over adjuvant chemotherapy (AC).

METHODS

We utilized data from the National Cancer Database (NCDB) for N+ and/or R1 pancreatic adenocarcinoma patients diagnosed from 2004 to 2012 who underwent ACR or AC. Patients who received neoadjuvant radiation, no adjuvant treatment, or adjuvant radiation alone were excluded. Propensity score nearest-neighbor 1:1 matching (PSM) was performed between ACR and AC groups based on age, sex, race, insurance, year of diagnosis, comorbidities, tumor site and size, T-stage, nodal status, margin status, grade, and treatment facility. Primary outcome was overall survival (OS).

RESULTS

A total of 8297 patients were eligible. After PSM, two well-balanced groups of 3244 patients each were analyzed. ACR resulted in superior OS compared with AC alone (Hazard ratio [HR] 0.83, 95% CI 0.79-0.87; median OS 22 vs 19 months, P < .0001). Subset analyses demonstrated OS benefit of ACR compared with AC in N+, R0 patients (HR: 0.82, 95% CI 0.77-0.88; Median OS 24 vs 20 months, P < .001) as well as N+, R1 patients (HR: 0.77, 95% CI 0.68-0.87; Median OS 17 vs 15 months, P < .001); but not in node-negative, R1 patients (HR: 1.12, 95% CI 0.84-1.48; Median OS 18 vs 22 months, P = .63).

CONCLUSION

The addition of radiation to AC was associated with a clinically small but meaningful increase in survival of patients undergoing curative-intent pancreatic resections. This association was not evident in patients with microscopically positive margins but node-negative disease and larger studies will be needed.

An update on treatment options for pancreatic adenocarcinoma

Pancreatic cancer is one of the most lethal solid organ tumors. Due to the rising incidence, late diagnosis, and limited treatment options, it is expected to be the second leading cause of cancer deaths in high income countries in the next decade. The multidisciplinary treatment of this disease depends on the stage of cancer at diagnosis (resectable, borderline, locally advanced, and metastatic disease), and combines surgery, chemotherapy, chemoradiotherapy, and supportive care. The landscape of multidisciplinary pancreatic cancer treatment is changing rapidly, especially in locally advanced disease, and the number of treatment options in metastatic disease, including personalized medicine, innovative targets, immunotherapy, therapeutic vaccines, adoptive T-cell transfer, or stemness inhibitors, will probably expand in the near future. This review summarizes the current literature and provides an overview of how new therapies or new therapeutic strategies (neoadjuvant therapies, conversion surgery) will guide multidisciplinary disease management, future clinical trials, and, hopefully, will increase overall survival.

Current Clinical Strategies of Pancreatic Cancer Treatment and Open Molecular Questions

Pancreatic cancer is one of the most lethal malignancies and is associated with a poor prognosis. Surgery is considered the only potential curative treatment for pancreatic cancer, followed by adjuvant chemotherapy, but surgery is reserved for the minority of patients with non-metastatic resectable tumors. In the future, neoadjuvant treatment strategies based on molecular testing of tumor biopsies may increase the amount of patients becoming eligible for surgery. In the context of non-metastatic disease, patients with resectable or borderline resectable pancreatic carcinoma might benefit from neoadjuvant chemo- or chemoradiotherapy followed by surgeryPatients with locally advanced or (oligo-/poly-)metastatic tumors presenting significant response to (neoadjuvant) chemotherapy should undergo surgery if R0 resection seems to be achievable. New immunotherapeutic strategies to induce potent immune response to the tumors and investigation in molecular mechanisms driving tumorigenesis of pancreatic cancer may provide novel therapeutic opportunities in patients with pancreatic carcinoma and help patient selection for optimal treatment.

Identifying Clinical Factors Which Predict for Early Failure Patterns Following Resection for Pancreatic Adenocarcinoma in Patients Who Received Adjuvant Chemotherapy Without Chemoradiation

OBJECTIVES

The role of radiation therapy (RT) in resected pancreatic cancer (PC) remains incompletely defined. We sought to determine clinical variables which predict for local-regional recurrence (LRR) to help select patients for adjuvant RT.

MATERIALS AND METHODS

We identified 73 patients with PC who underwent resection and adjuvant gemcitabine-based chemotherapy alone. We performed detailed radiologic analysis of first patterns of failure. LRR was defined as recurrence of PC within standard postoperative radiation volumes. Univariate analyses (UVA) were conducted using the Kaplan-Meier method and multivariate analyses (MVA) utilized the Cox proportional hazard ratio model. Factors significant on UVA were used for MVA.

RESULTS

At median follow-up of 20 months, rates of local-regional recurrence only (LRRO) were 24.7%, LRR as a component of any failure 68.5%, metastatic recurrence (MR) as a component of any failure 65.8%, and overall disease recurrence (OR) 90.5%. On UVA, elevated postoperative CA 19-9 (>90 U/mL), pathologic lymph node positive (pLN+) disease, and higher tumor grade were associated with increased LRR, MR, and OR. On MVA, elevated postoperative CA 19-9 and pLN+ were associated with increased MR and OR. In addition, positive resection margin was associated with increased LRRO on both UVA and MVA.

CONCLUSIONS

About 25% of patients with PC treated without adjuvant RT develop LRRO as initial failure. The only independent predictor of LRRO was positive margin, while elevated postoperative CA 19-9 and pLN+ were associated with predicting MR and overall survival. These data may help determine which patients benefit from intensification of local therapy with radiation.

Natural History and Treatment Trends in Pancreatic Cancer Subtypes

BACKGROUND

While pancreatic ductal adenocarcinoma is the most common form of pancreatic cancer, many other histologic forms of pancreatic cancer are also recognized. These histologic variants portray unique characteristics in terms of patient demographics, tumor behavior, survival, and responsiveness to treatments.

MATERIALS AND METHODS

Patients who underwent surgical resection of the pancreas for non-metastatic, invasive pancreatic cancer between 2004 and 2014 were selected from the National Cancer Data Base and categorized by histologic variant according to WHO classification guidelines. Patient demographics, tumor variables, treatment characteristics, and survival were compared between histologic groups and subgroups.

RESULTS

A total of 57,804 patients met inclusion and exclusion criteria and were grouped into eight major histologic categories. Survival analysis by the histologic group showed median overall survival of 20.2 months for ductal adenocarcinoma, 20.5 months for squamous cell carcinoma, 26.8 months for mixed acinar-neuroendocrine carcinomas, 52.6 months for cystic mucinous neoplasms with an associated invasive carcinoma, 67.5 months for acinar cell carcinoma, and 69.3 months for mesenchymal tumors. Median survival was not reached for neuroendocrine tumors and solid-pseudopapillary neoplasms, with 5-year overall survival rates of 84% and 97% respectively.

CONCLUSIONS

Rare subtypes of pancreatic cancer present unique clinicopathologic characteristics and display distinct tumor biologies. This study presents data on demographic, prognostic, treatment, and survival outcomes between rare forms of pancreatic neoplasms in order to aid understanding of the natural history and behavior of these neoplasms, with the hope of serving as a reference in clinical decision-making and ability to provide accurate prognostic information to patients.

Diagnostic and therapeutic recommendations in pancreatic ductal adenocarcinoma. Recommendations of the Working Group of the Polish Pancreatic Club

These recommendations refer to the current management in pancreatic ductal adenocarcinoma (PDAC), a neoplasia characterised by an aggressive course and extremely poor prognosis. The recommendations regard diagnosis, surgical, adjuvant and palliative treatment, with consideration given to endoscopic and surgical methods. A vast majority of the statements are based on data obtained in clinical studies and experts' recommendations on PDAC management, including the following guidelines: International Association of Pancreatology/European Pancreatic Club (IAP/EPC), American Society of Clinical Oncology (ASCO), European Society for Medical Oncology (ESMO), National Comprehensive Cancer Network (NCCN) and Polish Society of Gastroenterology (PSG) and The National Institute for Health and Care Excellence (NICE). All recommendations were voted on by members of the Working Group of the Polish Pancreatic Club. Results of the voting and brief comments are provided with each recommendation.

Chemotherapy Versus Chemoradiation as Preoperative Therapy for Resectable Pancreatic Ductal Adenocarcinoma: A Propensity Score Adjusted Analysis

OBJECTIVES

Although the use of neoadjuvant therapy for resectable pancreatic ductal adenocarcinoma is increasing, the optimal preoperative treatment regimen remains poorly defined.

METHODS

All patients with resectable pancreatic ductal adenocarcinoma who received preoperative chemotherapy alone (12%) or chemoradiation therapy (CRT) alone (88%) before pancreatectomy between 1999 and 2014 were included. Propensity score matching with inverse probability weighting was conducted based on age, baseline carbohydrate antigen 19-9, and procedure type.

RESULTS

Patients who received preoperative CRT were more likely to undergo a margin negative (91% vs 79%, P < 0.01) and node negative (53% vs 23%, P < 0.01) resection and experience less locoregional recurrence (LR; 16% vs 33%, P < 0.01) but similar median overall survival (OS; 33.6 vs 26.4 months, P = 0.09). On multivariate analysis, carbohydrate antigen 19-9 (hazard ratio, 1.2; 95% confidence interval [CI], 1.1-1.3) and positive lymph nodes (hazard ratio, 1.5; 95% CI, 1.0-2.2) were associated with OS, whereas tumor size (odds ratio [OR], 1.5; 95% CI, 1.3-1.8), positive lymph nodes (OR, 3.1; 95% CI, 1.8-5.6), and preoperative chemotherapy (OR, 1.8; 95% CI, 1.1-2.9) were associated with LR.

CONCLUSIONS

Preoperative CRT is associated with less margin and lymph node positivity, reduced LR, and similar OS compared with preoperative chemotherapy.

Adjuvant chemotherapy followed by concurrent chemoradiation is associated with improved survival for resected stage I-II pancreatic cancer

Background

This National Cancer Database (NCDB) analysis evaluates the clinical outcomes of postoperative chemotherapy followed by concurrent chemoradiation (C + CRT) compared to concurrent chemoradiation (CRT) alone or adjuvant chemotherapy alone (C) for resected pancreatic cancer.

Methods

The NCDB was queried for primary stage I‐II, cT1‐3N0‐1M0, resected pancreatic adenocarcinoma treated with adjuvant C, CRT, or C + CRT (2004‐2015). Patients treated with C + CRT were compared with those treated with C (cohort C) and CRT (cohort CRT). Baseline patient, tumor, and treatment characteristics were examined. Kaplan‐Meier analysis, multivariable Cox proportional hazards method, forest plot, and propensity score matching were used.

Results

Among 5667 patients, median follow‐up was 34.7, 45.2, and 39.7 months for the C, CRT, and C + CRT cohorts, respectively. By multivariable analysis for all patients, C and CRT had worse OS compared to C + CRT. Treatment interactions were seen among pathologically node‐positive disease. C + CRT was favored in 1‐3 and 4+ positive lymph node diseases when compared to C or CRT alone, but none of the treatment options were significantly favored in node negative disease. Using propensity score matching, 2152 patients for cohort C and 1774 patients for cohort CRT were matched. C + CRT remained significant for improved OS for both cohort C (median OS 23.3 vs 20.0 months) and cohort CRT (median OS 23.4 vs 20.8 months).

Conclusion

This NCDB study using propensity score matched analysis suggests an OS benefit for C + CRT compared to C or CRT alone following surgical resection of pancreatic cancer, particularly for patients with pathologically positive lymph nodes.

Large database utilization in health outcomes research in pancreatic cancer: an update

We sought to review published aggregate dataset studies on pancreatic cancer in the national and international settings, discuss the advantages and disadvantages these datasets possess, and possible future directions. A combination of Google Scholar, PubMed, and MEDLINE were used with search terms "pancreatic cancer" + "resectable" + "national cancer database", "pancreatic cancer" + "unresectable" + "national cancer database" and more broadly "borderline resectable pancreatic cancer", "locally advanced pancreatic cancer", "unresectable pancreatic cancer", and "resectable pancreatic cancer". Original articles and abstracts from this search were included, including data from the Surveillance, Epidemiology, and End Results (SEER) database, National Cancer Database (NCDB), and SEER-Medicare within the United States (US), as well as international database studies. Multiple database studies have been published regarding the role for radiotherapy in resected pancreatic cancer (n=6), the timing of additional therapy in resectable pancreatic cancer (n=4), and the role for radiotherapy and resection in locally advanced pancreatic cancer (LAPC) (n=4). Studies from both SEER and NCDB found a survival benefit to post-operative radiotherapy. In resectable pancreatic cancer, neoadjuvant treatment was found to be superior to adjuvant (NCDB). Chemoradiotherapy was found to be more beneficial than chemotherapy alone in LAPC, and patients who received highly-conformal or stereotactic body radiotherapy (SBRT) had improved survival compared to either conformal radiotherapy or chemotherapy alone. These studies also found that up to 10% of patients underwent resection, with a 90% margin-negative rate, and either one-half to one-third the risk of death of non-surgical patients. Criticism of large datasets includes lack of granularity of performance status, diagnosis, treatment, and outcomes-related data compared to properly administered prospective trials, as well as cross-over between treatment arms that cannot be accounted for, and concerns over quality of data represented. The US has witnessed a growing number of comparative effectiveness studies in pancreatic cancer. When taken together, certain themes emerge that are consistent with both single-institution data and clinical trials. These studies have also provided insight into questions not readily answerable by clinical trials. However, they require caution in interpretation.

Adjuvant therapeutic strategies for resectable pancreatic adenocarcinoma

Of all patients diagnosed with pancreatic adenocarcinoma, only 15-20% present with resectable disease. Despite curative-intent resection, the prognosis remains poor with the majority of patients recurring, prompting the need for adjuvant therapy. Historical data support the use of adjuvant 5-fluorouracil (5-FU) or gemcitabine, but recent data suggest either gemcitabine plus capecitabine or modified FOLFIRINOX can improve overall survival when compared to gemcitabine alone. The use of adjuvant chemoradiation therapy remains controversial, primarily due to limitations in study design and mixed results of historical trials. The ongoing Radiation Therapy Oncology Group (RTOG)-0848 trial hopes to further define the role of adjuvant chemoradiation therapy. Intraoperative radiation therapy (IORT) and adjuvant immunotherapy represent additional possibilities to improve outcomes, but evidence supporting their use is limited. This article reviews adjuvant therapeutic strategies for resectable pancreatic adenocarcinoma, including chemotherapy, chemoradiation therapy, IORT and immunotherapy.

Adjuvant radiotherapy and chemotherapy improve survival in patients with pancreatic adenocarcinoma receiving surgery: adjuvant chemotherapy alone is insufficient in the era of intensity modulation radiation therapy

In the era of intensity modulation radiation therapy (IMRT), no prospective randomized trial has evaluated the efficacy of adjuvant therapies such as adjuvant concurrent chemoradiotherapy (CCRT), adjuvant sequential chemotherapy and radiotherapy (CT-RT), and adjuvant CT alone in resectable pancreatic adenocarcinoma (PA). Through propensity score matching, we designed a nationwide, population-based, head-to-head cohort study to determine the effects of dissimilar adjuvant treatments on resectable PA. We minimized the confounding of various adjuvant treatment outcomes among the following resectable PA groups of patients from the Taiwan Cancer Registry database: group 1, adjuvant CCRT; group 2, adjuvant sequential CT-RT; and group 3, adjuvant CT alone. All the studied techniques are IMRTs. The matching process yielded a final cohort of 588 patients (196, 196, and 196 patients in groups 1, 2, and 3, respectively). In both univariate and multivariate Cox regression analyses, adjusted hazard ratios (aHRs; 95% confidence interval [CI]) of death derived for the adjuvant CCRT and adjuvant sequential CT-RT cohorts compared with the adjuvant CT alone cohort were 0.398 (0.314-0.504) and 0.307 (0.235-0.402), respectively. A combination of adjuvant IMRT and CT for resectable PA treatment improves survival to a greater extent than does adjuvant CT alone.

Nonmetastatic pancreatic cancer : Improved survival with chemoradiotherapy > 40 Gy after systemic treatment

Purpose

The role of radiotherapy (RT) for nonmetastatic pancreatic cancer is still a matter of debate since randomized control trials have shown inconsistent results. The current retrospective single-institution study includes both resected and unresected patients with nonmetastasized pancreatic cancer. The aim is to analyze overall survival (OS) after irradiation combined with induction chemotherapy.

Patients and methods

Of the 73 patients with nonmetastatic pancreatic cancer eligible for the present analysis, 42 (58%) patients had adjuvant chemoradiotherapy (CRT), while 31 (42%) received CRT as primary treatment. In all, 65 (89%) had chemotherapy at any time before, during, or after RT, and 39 (53%) received concomitant CRT. The median total dose was 50 Gy (range 12–77 Gy), while 61 (84%) patients received >40 Gy.

Results

With a median follow-up of 22 months (range 1.2–179.8 months), 14 (19%) are still alive and 59 (81%) of the patients have died, whereby 51 (70%) were cancer-related deaths. Median OS and the 2‑year survival rate were 22.9 months (1.2–179.8 months) and 44%, respectively. In addition, 61 (84%) patients treated with >40 Gy had a survival advantage (median OS 23.7 vs. 17.3 months, p = 0.026), as had patients with 4 months minimum of systemic treatment (median OS 27.5 vs. 14.3 months, p = 0.0004).

Conclusion

CRT with total doses >40 Gy after induction chemotherapy leads to improved OS in patients with nonmetastatic pancreatic cancer.

Electronic supplementary material

The online version of this article (10.1007/s00066-018-1281-7) contains supplementary material, which is available to authorized users.

Does adjuvant radiation provide any survival benefit after an R1 resections for pancreatic cancer?

BACKGROUND

The benefit of adding external beam radiation to adjuvant chemotherapy in patients that have undergone a margin positive resection for early stage, pancreatic ductal adenocarcinoma has not been determined definitively.

METHODS

The National Cancer Data Base was queried to evaluate the utility of adjuvant radiation in patients with pathologic stage I-II pancreatic ductal adenocarcinoma who underwent upfront pancreatoduodenectomy with a positive margin (margin positive resection) between 2004 and 2013.

RESULTS

In the study, 1,392 patients met inclusion criteria, of whom 263 (18.9%) were lymph node-negative (pathologic stages IA, IB, IIA) and 1,129 (81.1%) were node-positive (pathologic stage IIB); 938 (67.4%) patients received adjuvant radiation and chemotherapy, while 454 (32.6%) received adjuvant chemotherapy alone. Cox modeling stratified by nodal status demonstrated the benefit of radiation to be statistically significant only in node positive patients (hazard ratio 0.81, 95% confidence interval, 0.71-0.93). Node-positive patients receiving adjuvant radiation and chemotherapy had an adjusted median survival of 17.5 months vs 15.2 months for those receiving adjuvant chemotherapy alone (P=.003). In patients who had negative nodes, there was no difference in overall survival with radiation (22.5 vs 23.6 months, P=.511).

CONCLUSION

Addition of radiation to adjuvant chemotherapy after a margin positive resection confers a survival benefit albeit limited (about 2 months) in patients with node-positive pancreatic head cancer. (Surgery 2017;160:XXX-XXX.).

Dose-escalated radiotherapy for unresectable or locally recurrent pancreatic cancer: Dose volume analysis, toxicity and outcome of 28 consecutive patients

PURPOSE

The role of radiotherapy for unresectable pancreatic cancer is controversial. A benefit of additional radiotherapy is supported by some observations. A dose-effect relationship was recently found by dose escalation employing image guided and intensity modulated radiotherapy.

METHODS

We retrospectively evaluated 28 consecutive patients, all with history of extensive prior therapies for unresectable locally advanced/ recurrent pancreatic cancer (LAPC/LRPC). Treatment was delivered by helical tomotherapy after daily position verification with computed tomography. Dose to the planned target volume (PTV) was 51 Gy, while the dose to the macroscopic tumor was escalated by a simultaneous integrated boost to a median cumulative dose of 66 Gy (60-66 Gy). Concomitant chemotherapy consisted mainly of capecitabine (n = 23).

RESULTS

10 of 28 patients presented acute toxicities > grade 2, one patient succumbed to gastrointestinal bleeding after treatment. No correlations of toxicities and dose volume histograms (DVH) of retrospectively delineated small bowel loops were observed, although average small bowel volume receiving ≥ 20 Gy was 374 ml. DVH analyses revealed a correlation of splenic parameters and acute toxicity: Vomiting, anorexia, dehydration, hematologic toxicity, fatigue, combined gastro-intestinal toxicity wit R-values between 0.392 and 0.561 (all p-values > 0.05). Only one patient developed late toxicities > grade 2. With an average follow-up time in surviving patients of 14 months median overall survival time was 19 months and median time to local recurrence 13 months. In 8 patients with available imaging of local recurrence: 5 in field recurrences, 2 marginal recurrences and one lymph node recurrence outside the high dose radiation field were observed. In univariate analysis only ΔCA-19-9 during radiotherapy was associated with local control (p = 0.029) and overall survival (p = 0.049).

CONCLUSION

Dose escalated normo-fractionated radiotherapy for LAPC/LRPC seems feasible and suitable to prolong local control and in consequence long-term survival. However, in-field local progression is still frequently observed and possibilities to increase the local effectiveness should be evaluated. Exposure of the spleen was predictive for acute toxicity and should be further investigated.

Evolving treatment landscape for early and advanced pancreatic cancer

Pancreatic ductal adenocarcinoma is an infrequent cancer with a high disease related mortality rate, even in the context of early stage disease. Until recently, the rate of death from pancreatic cancer has remained largely similar whereby gemcitabine monotherapy was the mainstay of systemic treatment for most stages of disease. With the discovery of active multi-agent chemotherapy regimens, namely FOLFIRINOX and gemcitabine plus nab-paclitaxel, the treatment landscape of pancreatic cancer is slowly evolving. FOLFIRINOX and gemcitabine plus nab-paclitaxel are now considered standard first line treatment options in metastatic pancreatic cancer. Studies are ongoing to investigate the utility of these same regimens in the adjuvant setting. The potential of these treatments to downstage disease is also being actively examined in the locally advanced context since neoadjuvant approaches may improve resection rates and surgical outcomes. As more emerging data become available, the management of pancreatic cancer is anticipated to change significantly in the coming years.

Neoadjuvant therapy in pancreatic cancer: a systematic review and meta-analysis of prospective studies

There is a strong rationale and many theoretical advantages for neoadjuvant therapy in pancreatic cancer (PC). However, study results have varied significantly. In this study, a systematic review and meta‐analysis of prospective studies were performed in order to evaluate safety and effectiveness of neoadjuvant therapy in PC. Thirty‐nine studies were selected (n = 1458 patients), with 14 studies focusing on patients with resectable disease (group 1), and 19 studies focusing on patients with borderline resectable and locally advanced disease (group 2). Neoadjuvant chemotherapy was administered in 97.4% of the studies, in which 76.9% was given radiotherapy and 74.4% administered with chemoradiation. The complete and partial response rate was 3.8% and 20.9%. The incidence of grade 3/4 toxicity was 11.3%. The overall resection rate after neoadjuvant therapy was 57.7% (group 1: 73.0%, group 2: 40.2%). The R0 resection rate was 84.2% (group 1: 88.2%, group 2: 79.4%). The overall survival for all patients was 16.79 months (resected 24.24, unresected 9.81; group 1: 17.76, group 2: 16.20). Our results demonstrate that neoadjuvant therapy has not been proven to be beneficial and should be considered with caution in patients with resectable PC. Patients with borderline resectable or locally advanced disease may benefit from neoadjuvant therapy, but further research is needed.

Insurance Status Is Related to Receipt of Therapy and Survival in Patients with Early-Stage Pancreatic Exocrine Carcinoma

Objectives. The study objective was to determine how insurance status relates to treatment receipt and overall survival for patients with early-stage pancreatic exocrine carcinoma. Methods. SEER data were evaluated for 17,234 patients diagnosed with Stage I/II pancreatic exocrine carcinoma. Multivariate regression models controlled for personal characteristics to determine whether insurance status was independently associated with overall survival and receipt of radiation/surgery. Results. Odds of receiving radiation were 1.50 and 1.75 times higher for insured patients compared to Medicaid and uninsured patients, respectively (p < 0.01). Insured patients had 1.68 and 1.57 times increased odds of receiving surgery compared to Medicaid and uninsured patients (p < 0.01). Risk of death was 1.33 times greater (p < 0.01) in Medicaid patients compared to insured patients; when further adjusted for treatment, the risk of death was attenuated but remained significant (HR = 1.16, p < 0.01). Risk of death was 1.16 times higher for uninsured patients compared to insured patients (p = 0.02); when further adjusted for treatment, the risk of death was no longer significant (HR = 1.01, p = 0.83). Conclusions. Uninsured and Medicaid-insured patients experience lower treatment rates compared to patients who have other insurances. The increased likelihood of treatment appears to explain the insured group's survival advantage.

Value of apparent diffusion coefficient prior to neoadjuvant therapy is a predictor of histologic response in patients with borderline resectable pancreatic carcinoma

BACKGROUND

The parameters to predict histological response to neoadjuvant therapy remain controversial in borderline resectable pancreatic carcinoma (BRPC).

METHODS

Twenty-four patients who underwent diffusion-weighted magnetic resonance imaging (DW-MRI) prior to expected neoadjuvant chemo/chemoradiotherapy and surgery were reviewed retrospectively. Analyses for correlation between percent tumor cell destruction and the following was performed to investigate the parameter and cut off value: tumor size, whole tumor apparent diffusion coefficient (ADC) value of DW-MRI, maximum standardized uptake value of 18 F-fluorodeoxyglucose positron emission tomography, carbohydrate antigen 19-9, and their change ratios. The selected parameter was assessed for prediction ability of the histological response to neoadjuvant chemo/chemoradiotherapy and R0 curability.

RESULTS

Pre-treatment ADC value was correlated with tumor cell destruction rate among all parameters (R = 0.625, P = 0.001). The ADC cut-off value for discriminating between nonresponders (grade I) and responders (grade IIa and more) after treatment was determined as 1.20 × 10-3  mm2 /s and the sensitivity, 100%; specificity, 75%; accuracy, 83% for responder, and the sensitivity, 100%; specificity, 63%; accuracy, 71% for R0 curability.

CONCLUSIONS

Pre-treatment ADC value appeared to be a predictor of R0 curability in BRPC patients because of effective histological response to neoadjuvant therapy, and there was a significant correlation between the baseline ADC value and histological tumor cell destruction rate.

Multimodal treatment of resectable pancreatic ductal adenocarcinoma

After a timing preoperative staging, treatment of resectable pancreatic adenocarcinoma (PDAC) includes surgery and adjuvant therapies, the former representing the initial therapeutic option and the latter aiming to reduce the incidence of both distant metastases (chemotherapy) and locoregional failures (chemoradiotherapy). Herein, we provide a critical overview on the role of multimodal treatment in PDAC and on new opportunities related to current more active poli-chemotherapy regimens, targeted therapies, and the more recent immunotherapy approaches. Moreover, an analysis of pathological markers and clinical features able to help clinicians in the selection of the best therapeutic strategy will be discussed. Lastly, the role of neoadjuvant treatment of initially resectable disease will be considered mostly in patients whose malignancy shows morphological but not clinical or biological criteria of resectability. Depending on the results of these investigational studies, today a multidisciplinary approach can offer the best address therapy for these patients.