Neoadjuvant treatment for resectable pancreatic cancer: Time for phase III testing?

The Role of Endoscopic Ultrasonography in the Diagnosis and Staging of Pancreatic Cancer

Pancreatic cancer is the fourth leading cause of cancer-related death and the second gastrointestinal cancer-related death in the United States. Early detection and accurate diagnosis and staging of pancreatic cancer are paramount in guiding treatment plans, as surgical resection can provide the only potential cure for this disease. The overall prognosis of pancreatic cancer is poor even in patients with resectable disease. The 5-year survival after surgical resection is ~10% in node-positive disease compared to ~30% in node-negative disease. The advancement of imaging studies and the multidisciplinary approach involving radiologists, gastroenterologists, advanced endoscopists, medical, radiation, and surgical oncologists have a major impact on the management of pancreatic cancer. Endoscopic ultrasonography is essential in the diagnosis by obtaining tissue (FNA or FNB) and in the loco-regional staging of the disease. The advancement in EUS techniques has made this modality a critical adjunct in the management process of pancreatic cancer. In this review article, we provide an overall description of the role of endoscopic ultrasonography in the diagnosis and staging of pancreatic cancer.

β-catenin plus PROX1 immunostaining stratifies disease progression and patient survival in neoadjuvant-treated pancreatic cancer

BACKGROUND

Wnt/β-catenin signaling is a highly conserved signaling pathway that regulates the transcription factor PROX1. The role of β-catenin and PROX1 in pancreatic cancer is ambiguous, as some studies have associated their expression with tumor regression and some with tumor progression.

OBJECTIVE

We have investigated their expression in surgically treated pancreatic cancer patients receiving neoadjuvant therapy (NAT), and patients treated upfront with surgery (US). We furthermore compared the expression of β-catenin and PROX1 between patients who had a good or poor response to NAT.

METHODS

We evaluated β-catenin and PROX1 expression through immunohistochemistry in 88 neoadjuvant and 144 upfront surgery patients by scoring the intensity of the immunopositivity as 0-3, corresponding to negative, weak, moderate, or strong. We developed a six-tier grading scheme for the neoadjuvant responses by analyzing the remaining tumor cells in surgical specimen histological sections.

RESULTS

Strong β-catenin immunopositivity associated with improved survival in the patients with good NAT-response (≤10% residual tumor cells) (Hazard ratio [HR] 0.26 95%, confidence interval [CI] 0.07-0.88 p = 0.030). Additionally, the combined moderate β-catenin and PROX1 expression associated with improved survival (HR 0.20 95% CI 0.05-0-76 p = 0.018) among the good responders. Among the patients with a poor NAT-response (> 10% residual tumor cells), both strong β-catenin immunopositivity and strong combined β-catenin and PROX1 associated with shorter survival (HR 2.03 95% CI 1.16-3.55 p = 0.013, and HR 3.1 95% CI 1.08-8.94 p = 0.03, respectively). PROX1 alone was not associated with survival.

CONCLUSIONS

Strong β-catenin immunopositivity and combined strong or moderate β-catenin and PROX1 immunopositivity associated with improved survival among the good NAT-responders and worse survival among the poor NAT-responders.

Neoadjuvant Therapy is Essential for Resectable Pancreatic Cancer

BACKGROUND

Awareness of the benefits of neoadjuvant therapy is increasing, but its use as an initial therapeutic option for patients with resectable pancreatic cancer remains controversial, especially for those patients without high-risk prognostic features. Even for patients with high-risk features who are candidates to receive neoadjuvant therapy, no standard regimen exists.

METHODS

In this review, we examined available data on the neoadjuvant therapy in patients with resectable pancreatic cancer, including prospective studies, retrospective studies, and ongoing clinical trials, by searching PubMed/MEDLINE, ClinicalTrials.gov, Web of Science, and Cochrane Library. The characteristics and results of screened studies were described.

RESULTS

Retrospective and prospective studies with reported results and ongoing randomized studies were included. For patients with resectable pancreatic cancer, neoadjuvant therapy provides benefits such as increased survival, decreased risk of comorbidities and mortality, and improved cost-effectiveness due to an increased completion rate of multimodal treatment. Highly active regimens such as FOLFIRINOX (folinic acid, fluorouracil, irinotecan, and oxaliplatin) or gemcitabine plus nab-paclitaxel are considered acceptable therapeutic regimens. Additionally, platinum-containing regimens other than FOLFIRINOX are acceptable for selected patients. Other therapies, such as chemoradiation treatment, immuno-oncology agents, and targeted therapies are being explored and the results are highly anticipated.

CONCLUSION

This review highlights the benefits of neoadjuvant therapy for resectable pancreatic cancer. Some regimens are currently acceptable, but need more evidence from well-designed clinical trials or should be used after being carefully examined by a multidisciplinary team.

Neoadjuvant radiation followed by resection versus upfront resection for locally advanced pancreatic cancer patients: a propensity score matched analysis

BACKGROUND AND AIM

To compare cancer-specific survival (CSS) between patients who received neoadjuvant radiation followed by resection (NRR) and those who received upfront resection (UR) for locally advanced pancreatic cancer (LAPC).

METHODS

A total of 772 LAPC patients who underwent curative-intent surgical resection with or without neoadjuvant radiation from 2004 to 2013 were identified from the Surveillance, Epidemiology, and End Result (SEER) database. Propensity score matching (PSM) was conducted to eliminate possible bias. Kaplan-Meier method was used to analyze long-term outcome. Independent risk factors of CSS were predicted by Cox proportional hazards model. Subgroup analyses were done according to 5 variables.

RESULTS

The propensity score model matched 196 patients from the whole cohort. Neoadjuvant radiation was an independent predictor of CSS no matter before or after PSM. After PSM, the 1-, 3-, 5-year CSS rates of NRR group were 82.7%, 39.2% and 17.1%, while 64.3%, 19.9% and 12.4% for UR group. The median CSS for NRR group was 25 months, while 17 months for UR group. In subgroup analyses, CSS rates or median CSS of NRR group were still superior to those of UR group in married, unmarried, pancreatic adenocarcinoma, G1+G2, G3+G4, N0 stage, N1 stage and M0 stage subgroups, but no differences were found in other histological types and M1 stage subgroups. Other predictors of CSS included histological type, tumor grade and marital status.

CONCLUSIONS

Neoadjuvant radiation followed by resection has a significant survival benefit compared with upfront resection in LAPC patients. Therapeutic strategy for LAPC patients should be further explored.

Clinical and pathological features of five-year survivors after pancreatectomy for pancreatic adenocarcinoma

BACKGROUND

Clinical factors determining short-term survival after pancreatectomy have been well studied, but factors predicting long-term survival with curative resection are poorly understood in pancreatic carcinoma. Our objective was to identify clinical and pathological features of five-year disease-free survivors after surgical resection of pancreatic adenocarcinoma.

METHODS

The clinical and pathological data from 147 patients who underwent a potentially curative resection for pancreatic adenocarcinoma at our institution between 1988 and 2012 were retrospectively analyzed.

RESULTS

Of 147 patients, 18 survived for more than five years after surgery without disease recurrence. A univariate analyses demonstrated that: two or fewer lymph node metastases (P=0.014), a preoperative serum carbohydrate antigen 19-9 (CA19-9) level of 40 U/mL or less (P=0.0018), an absence of intrapancreatic nerve invasion (P=0.028), and undergoing an R0 resection (P=0.011) were significantly associated with five-year survival. A logistic regression model identified the following independent cancer-related predictors of five-year survivors: having two or fewer lymph node metastases (odds ratio (OR): 6.02; 95% confidence interval (CI): 1.08 to 112.98; P=0.0385), a preoperative serum CA19-9 level of 40 U/mL or less (OR: 5.02; 95% CI: 1.68 to 16.48; P=0.0036), and undergoing an R0 resection (OR: 3.63; 95% CI: 1.12 to 14.28; P=0.0316).

CONCLUSIONS

We conclude that number of lymph node metastases being two or less, a preoperative serum CA19-9 level of 40 U/mL or less, and undergoing an R0 resection may be independent predictive factors to identify actual five-year survivors after pancreatectomy for pancreatic adenocarcinoma.

Influence of preoperative anti-cancer therapy on resectability and perioperative outcomes in patients with pancreatic cancer: project study by the Japanese Society of Hepato-Biliary-Pancreatic Surgery

BACKGROUND

Little is known about the effects of neoadjuvant therapy on outcomes in patients with pancreatic cancer. This study evaluated the effects of neoadjuvant therapy on resectability and perioperative outcomes.

METHODS

A total of 992 patients were enrolled, with 971 deemed eligible. Of these, 582 had resectable tumors and 389 had borderline resectable tumors, and 388 patients received neoadjuvant therapy. Demographic characteristics and peri- and postoperative parameters were assessed by a questionnaire survey.

RESULTS

The R0 rate was significantly higher in patients with resectable tumors who received neoadjuvant therapy than in those who underwent surgery first, but no significant difference was noted in patients with borderline resectable tumors. Operation time was significantly longer and blood loss was significantly greater in patients who received neoadjuvant therapy than in those who underwent surgery first, but there were no significant differences in specific complications and mortality rates. The node positivity rate was significantly lower in the neoadjuvant than in the surgery-first group, indicating that the former had significantly lower stage tumors.

CONCLUSIONS

Neoadjuvant therapy may not increase the mortality and morbidity rate and may be able to increase the chance for curative resection against resectable tumor.

Neoadjuvant chemotherapy with gemcitabine and S-1 for resectable and borderline pancreatic ductal adenocarcinoma: results from a prospective multi-institutional phase 2 trial

BACKGROUND

Surgical resection is the only curative strategy for pancreatic ductal adenocarcinoma (PDAC), but recurrence rates are high even after purported curative resection. First-line treatment with gemcitabine and S-1 (GS) is associated with promising antitumor activity with a high response rate. The aim of this study was to assess the feasibility and efficacy of GS in the neoadjuvant setting.

METHODS

In a multi-institutional single-arm phase 2 study, neoadjuvant chemotherapy (NAC) with gemcitabine and S-1, repeated every 21 days, was administered for two cycles (NAC-GS) to patients with resectable and borderline PDAC. The primary end point was the 2-year survival rate. Secondary end points were feasibility, resection rate, pathological effect, recurrence-free survival, and tumor marker status.

RESULTS

Of 36 patients enrolled, 35 were eligible for this clinical trial conducted between 2008 and 2010. The most common toxicity was neutropenia in response to 90% of the relative dose intensity. Responses to NAC included radiological tumor shrinkage (69%) and decreases in CA19-9 levels (89%). R0 resection was performed for 87% in resection, and the morbidity rate (40%) was acceptable. The 2-year survival rate of the total cohort was 45.7%. Patients who underwent resection without metastases after NAC-GS (n = 27) had an increased median overall survival (34.7 months) compared with those who did not undergo resection (P = 0.0017).

CONCLUSIONS

NAC-GS was well tolerated and safe when used in a multi-institutional setting. The R0 resection rate and the 2-year survival rate analysis are encouraging for patients with resectable and borderline PDAC.

Combined modality treatments in pancreatic cancer

INTRODUCTION

Of all the carcinomas, pancreatic carcinoma (PC) has the highest mortality rate, with a 1- and 5-year survival rate of 25% and less than 5% respectively. This is regardless of the stage at diagnosis.

AREAS COVERED

In this review relevant literature assessing the evidence regarding preoperative and adjuvant chemoradiotherapy (CRT) is discussed. Furthermore, new therapeutic approaches are summarized, while the future direction regarding the multimodality approach to PC is also discussed.

EXPERT OPINION

The role of combined-modality therapy for PC is continuously evolving. There have been several recent developments, as well as the completion of major, multi-institutional clinical trials. One of the challenges for the busy clinician is to appreciate the variation in staging, surgical expertise, and application of either definitive CRT or neo-adjuvant CRT for local and/or borderline disease.

Adjuvant therapy for pancreatic cancer

Pancreatic cancer is a challenging malignancy to treat, as less than one-fifth of diagnosed cases are resectable, surgery is complex and postoperative recovery slow, treated patients tend to relapse and overall survival rates are low. It is one of the leading causes of cancer-related mortality. Adjuvant therapy has been employed in resectable disease, to target micrometastases and improve prognosis. Chemotherapy, chemoradiotherapy (chemoRT) and chemoradiotherapy (chemoRT) followed on by chemotherapy have been evaluated in randomised controlled trials. The European Study Group for Pancreatic Cancer (ESPAC)-1 and CONKO-001 trials clearly established the survival advantage of adjuvant chemotherapy with 5 fluorouracil (5FU) plus folinic acid and gemcitabine respectively over no chemotherapy. The ESPAC-3 (version 2) trial demonstrated equivalence between 5FU plus folinic acid and gemcitabine in terms of survival parameters, though gemcitabine had a better toxicity profile. The results of these key studies, together with smaller ones have been subjected to meta-analyses, with confirmation of improved survival with adjuvant systemic chemotherapy. The EORTC-40891 and ESPAC-1 trials found no survival advantage with adjuvant chemoRT compared to observation, and this has been reflected in a subsequent meta-analysis. The popularisation of chemoRT, with follow on chemotherapy (versus observation) was based on the small underpowered GITSG trial. The ESPAC-1 trial was unable to find a survival benefit for chemoRT, with follow on chemotherapy compared to observation. The RTOG-9704 trial assessed chemoRT with follow on chemotherapy in both arms and found no difference between survival in the gemcitabine and 5FU arms. There has never been a published head-to-head randomised comparison of adjuvant chemotherapy to chemoRT, with follow on chemotherapy. Ongoing randomised trials are looking into adjuvant combination chemotherapy, chemotherapy with follow on chemoRT, and neoadjuvant therapy. Novel agents continue to be assessed in early phase trials with a major emphasis on predictive and prognostic biomarkers. Based on the available evidence, adjuvant chemotherapy with gemcitabine or 5FU/folinic acid is the current recommended gold standard in the management of resected pancreatic cancer.

Neoadjuvant therapy in pancreatic adenocarcinoma: a meta-analysis of phase II trials

BACKGROUND

Neoadjuvant treatment has proven beneficial for many gastrointestinal (GI) malignancies, but no phase III trials have been completed examining this approach in pancreatic cancer. This meta-analysis examines the best available phase II trials using neoadjuvant treatment for resectable and borderline/unresectable pancreatic adenocarcinoma.

METHODS

Phase II trials were identified using a MEDLINE search, and the Cochrane Central Register of Controlled Trials from 1960 to July 2010. Patients were divided into 2 groups: Patients with initially resectable tumors (group A), and patients with borderline/unresectable tumors (group B). Primary outcome measures were rate of resection and survival. Pooled proportions and 95% confidence intervals (CIs) were calculated using random-effects or fixed-effects models based on the heterogeneity of included studies.

RESULTS

A total of 14 phase II clinical trials including 536 patients were analyzed. After treatment, resectability was 65.8% (95% CI, 55.4-75.6%) compared with 31.6% in group B (95% CI, 14.0-52.5%). A partial response was observed in patients with borderline/unresectable tumors; 31.8 (95% CI, 24.2-39.8%) in group B and 9.5% (95% CI, 2.9-19.4%) in group A (P = .003). Progressive disease was seen in 17.0% (95% CI, 11.9-22.7) of patients in group A versus 21.8% (95% CI, 10.1-36.5%) in group B (P = .006). Median survival in resected patients was 23 months for group A and 22 months for group B.

CONCLUSION

Neoadjuvant treatment seems to have some activity in patients with borderline/unresectable pancreatic adenocarcinoma. Nearly one third of tumors initially deemed marginal for operative intervention were able to be ultimately resected after treatment. Until more effective targeted chemotherapeutics are developed, the only group of patients with pancreatic cancer that may benefit from neoadjuvant treatment are those with locally advanced disease.

Pancreatic cancer biomarkers and their implication in cancer diagnosis and epidemiology

Pancreatic cancer is the fourth most common cause of cancer-related mortality in the United States. Biomarkers are needed to detect this cancer early during the disease development and for screening populations to identify those who are at risk. In cancer, “biomarker” refers to a substance or process that is indicative of the presence of cancer in the body. A biomarker might be either a molecule secreted by a tumor or it can be a specific response of the body to the presence of cancer. Genetic, epigenetic, proteomic, glycomic, and imaging biomarkers can be used for cancer diagnosis, prognosis, and epidemiology. A number of potential biomarkers have been identified for pancreatic cancer. These markers can be assayed in non-invasively collected biofluids. These biomarkers need analytical and clinical validation so that they can be used for the purpose of screening and diagnosing pancreatic cancer and determining disease prognosis. In this article, the latest developments in pancreatic cancer biomarkers are discussed.