Trials and tribulations of neoadjuvant therapy in pancreatic cancer

Management of Advanced Pancreatic Cancer through Stromal Depletion and Immune Modulation

Pancreatic cancer is one of the leading causes of cancer-related deaths worldwide. Unfortunately, therapeutic gains in the treatment of other cancers have not successfully translated to pancreatic cancer treatments. Management of pancreatic cancer is difficult due to the lack of effective therapies and the rapid development of drug resistance. The cytotoxic agent gemcitabine has historically been the first-line treatment, but combinations of other immunomodulating and stroma-depleting drugs are currently undergoing clinical testing. Moreover, the treatment of pancreatic cancer is complicated by its heterogeneity: analysis of genomic alterations and expression patterns has led to the definition of multiple subtypes, but their usefulness in the clinical setting is limited by inter-tumoral and inter-personal variability. In addition, various cell types in the tumor microenvironment exert immunosuppressive effects that worsen prognosis. In this review, we discuss current perceptions of molecular features and the tumor microenvironment in pancreatic cancer, and we summarize emerging drug options that can complement traditional chemotherapies.

Outcome of neoadjuvant treatment for pancreatic cancer in elderly patients: comparative, observational cohort study

BACKGROUND

Use of neoadjuvant therapy for elderly patients with pancreatic cancer has been debatable. With FOLFIRINOX (folinic acid, 5-fluorouracil, irinotecan, oxaliplatin) or gemcitabine plus nab-paclitaxel (GnP) showing tremendous effects in improving the overall survival of patients with borderline resectable and locally advanced pancreatic cancer, there is no definitive consensus regarding the use of this regimen in the elderly.

METHODS

This study evaluated the eligibility of elderly patients with borderline resectable or locally advanced pancreatic cancer for neoadjuvant therapy. Patients registered in the database of pancreatic cancer at the University of Colorado Cancer Center, who underwent neoadjuvant treatment between January 2011 and March 2019, were separated into three age groups (less than 70, 70-74, 75 or more years) and respective treatment outcomes were compared.

RESULTS

The study included 246 patients with pancreatic cancer who underwent neoadjuvant treatment, of whom 154 and 71 received chemotherapy with FOLFIRINOX and GnP respectively. Among these 225 patients, 155 were younger than 70 years, 36 were aged 70-74 years, and 34 were aged 75 years or older. Patients under 70 years old received FOLFIRINOX most frequently (124 of 155 versus 18 of 36 aged 70-74 years, and 12 of 34 aged 75 years or more; P < 0.001). Resectability was similar among the three groups (60.0, 58.3, and 55.9 per cent respectively; P = 0.919). Trends towards shorter survival were observed in the elderly (median overall survival time 23.6, 18.0, and 17.6 months for patients aged less than 70, 70-74, and 75 or more years respectively; P = 0.090). After adjusting for co-variables, age was not a significant predictive factor.

CONCLUSION

The safety and efficacy of multiagent chemotherapy in patients aged 75 years or over were similar to those in younger patients. Modern multiagent regimens could be a safe and viable treatment option for clinically fit patients aged at least 75 years.

Impact of Neoadjuvant Systemic Therapy on Pancreatic Fistula Rates Following Pancreatectomy: a Population-Based Propensity-Matched Analysis

INTRODUCTION

Postoperative pancreatic fistula (POPF) drives morbidity and mortality following pancreatectomy. Use of neoadjuvant chemotherapy (NAC) has recently increased in the treatment of potentially resectable pancreatic ductal adenocarcinoma (PDAC). This study examined the effect of NAC on POPF rates and postoperative outcomes in PDAC.

METHODS

The American College of Surgeons-National Surgical Quality Improvement Program (NSQIP) Targeted Pancreatectomy dataset was queried to identify PDAC patients who underwent curative-intent pancreatectomies. Propensity score matching was used to stratify patients by receipt of NAC. Postoperative outcomes were compared and logistic regression applied to identify POPF predictors.

RESULTS

Six thousand eight hundred sixty-three patients met the inclusion criteria; of those, 1908 (27.8%) received NAC and 4955 (72.2%) did not (NNAC). Two thousand sixty-two patients were matched 1:1 from each group. NAC patients had significantly lower POPF rates (9.0% vs. 14.5%; P < 0.001); the majority were categorized as grade A (5.1% vs. 9.5%). Overall 30-day morbidity was lower with NAC (40.4% vs. 49.5%; P < 0.001). Specifically, pneumonia (2.3% vs. 4.1%), organ space infections (7.9% vs. 13.2%), sepsis (5.2% vs. 8.0%), and delayed gastric emptying (10.1% vs. 14.8%) occurred less frequently in the NAC group. Postoperative mortality and unplanned reoperations were similar. On multivariate analysis, receipt of NAC was an independent predictor of decreased POPF rates (HR, 0.73 [0.56-0.94]; P = 0.016). Other factors included gland texture, duct size, male gender, and lower BMI.

CONCLUSIONS

In this propensity-matched, population-based cohort study of PDAC patients, NAC was associated with lower POPF rates and overall major complications. Those findings suggest a modest protective effect of NAC from POPF.

Neoadjuvant and Adjuvant Therapy in Operable Pancreatic Cancer: Both Honey and Milk (but No Bread?)

Pancreatic cancer has a dismal prognosis. Resection is the best option for cure, supported by multimodal therapy to treat the systemic disease. While adjuvant therapy has become standard in those who are fit and who can tolerate the given regimen, the concept of perioperative (neoadjuvant) therapy is building momentum. The concepts of “borderline” and “locally advanced” have changed the previous dichotomized “resectable/non-resectable” into subcategories for which new algorithms have emerged, with neoadjuvant therapy discussed both for upfront resectable pancreatic cancer, for those deemed borderline resectable, and as “induction or conversion” therapy for locally advanced disease. The purpose of this invited commentary is to discuss some of the changing paradigms in multimodal therapy for operable pancreatic cancer. The PREOPANC trial presented randomized data on the role of neoadjuvant therapy for resectable and borderline cancers, but new questions have emerged. The role of combination therapy in the preoperative setting is discussed in the light of this trial. FOLFIRINOX has emerged as the most potent treatment regimen in the metastatic and adjuvant setting, but with no level I data to support neoadjuvant use yet. Several trials are ongoing to arrive at the best answer.

Postoperative pancreatic fistulas decrease the survival of pancreatic cancer patients treated with surgery after neoadjuvant chemoradiotherapy: A retrospective analysis

BACKGROUND AND OBJECTIVES

A postoperative pancreatic fistula (POPF) is a critical complication after surgery for pancreatic cancer. Whether a POPF affects the long-term prognosis of pancreatic cancer cases remains controversial. This study aimed to clarify the effect of a POPF on the long-term prognosis of pancreatic cancer patients, especially after neoadjuvant chemoradiotherapy (NACRT).

METHODS

Patients who underwent curative pancreatectomy for pancreatic cancer between January 2012 and June 2019 at Kyoto University Hospital were retrospectively investigated. A fistula ≥ Grade B was considered a POPF.

RESULTS

During the study period, 148 patients underwent upfront surgery (Upfront group), and 52 patients underwent surgery after NACRT (NACRT group). A POPF developed in 16% of patients in the Upfront group and 13% in the NACRT group (p = 0.824). In the Upfront group, development of a POPF did not have a significant effect on recurrence-free survival (p = 0.766) or overall survival (p = 0.863). However, in the NACRT group, development of a POPF significantly decreased recurrence-free survival (HR 5.856, p = 0.002) and overall survival (HR 7.097, p = 0.020) on multivariate analysis.

CONCLUSIONS

The development of a POPF decreases the survival of pancreatic cancer patients treated by surgery after NACRT.

Therapeutic resistance of pancreatic cancer: Roadmap to its reversal

Pancreatic cancer is a lethal disease with limited opportunity for resectable surgery as the first choice for cure due to its late diagnosis and early metastasis. The desmoplastic stroma and cellular genetic or epigenetic alterations of pancreatic cancer impose physical and biological barriers to effective therapies, including chemotherapy, radiotherapy, targeted therapy, and immunotherapy. Here, we review the current therapeutic options for pancreatic cancer, and underlying mechanisms and potential reversal of therapeutic resistance, a hallmark of this deadly disease.

Vascular Resections for Pancreatic Ductal Adenocarcinoma: Vascular Resections for PDAC

BACKGROUND AND AIMS

It has become clear that vein resection and reconstruction for pancreatic ductal adenocarcinoma (PDAC) is the standard of care as supported by multiple guidelines. However, resection of large peri-pancreatic arteries remains debatable.

MATERIALS AND METHODS

This review examines the current state of vascular resection with curative intent for PDAC in the last 5 years. Herein, we consider venous (superior mesenteric vein, portal vein), as well as arterial (superior mesenteric artery, celiac trunk, hepatic artery) resection or both with or without reconstruction.

RESULTS

Improvement of multidrug chemotherapy has revolutionized care for PDAC that should shift traditional surgical thinking from an anatomical classification of resectability to a prognostic and biological classification.

CONCLUSION

The present review gives an overview on the results of pancreatectomy associated with vascular resection, with consideration of new perspectives offered by the availability of better systemic therapies.

Management of isolated recurrence after surgery for pancreatic adenocarcinoma

BACKGROUND

Recurrence of pancreatic cancer after primary pancreatectomy occurs in the vast majority of patients. The role of surgical treatment for recurrent pancreatic cancer is not well established.

METHODS

Patients who underwent primary pancreatectomy with curative intent from 2000 to 2014 at a single large-volume centre were evaluated retrospectively. CT or PET was used to select patients with an isolated recurrence. The clinicopathological features and survival outcomes were compared according to treatment modalities.

RESULTS

Of the 1610 patients with pancreatic cancer who underwent resection, 1346 (83·6 per cent) were diagnosed with recurrent pancreatic cancer. Recurrence was locoregional in 366 patients (27·2 per cent), distant multifocal in 251 (18·6 per cent), distant isolated in 188 (14·0 per cent), locoregional plus distant in 153 (11·4 per cent) and peritoneal seeding in 388 (28·8 per cent). Of the 1346 patients with recurrence, 197 (14·6 per cent) had isolated recurrence; of these, 48 (24·4 per cent of all isolated recurrences; 3·6 per cent of all recurrences) underwent resection. Median survival of the 197 patients after diagnosis of isolated recurrence was 14·7 months; it was longer in patients who underwent surgical resection than among those treated non-surgically (23·5 versus 12·0 months; P = 0·014). Multivariable analysis showed that chemotherapy and resection for recurrence were associated with better prognosis. Median survival after recurrence was longest in the 23 patients with isolated pulmonary recurrence (33·3 months). Survival after recurrence was better in patients who underwent resection of isolated recurrence in the remnant pancreas (median 28·0 versus 12·0 months, P = 0·010) and lung (median 36·5 versus 9·5 months; P = 0·010) than in those who did not undergo resection.

CONCLUSION

Surgical resection may be considered an option for treatment of patients with isolated recurrent pancreatic cancer.

Association Between Pancreatic Fistula and Long-term Survival in the Era of Neoadjuvant Chemotherapy

Importance

In the past decade, the use of neoadjuvant therapy (NAT) has increased for patients with borderline and locally advanced pancreatic ductal adenocarcinoma (PDAC). Data on pancreatic fistula and related overall survival (OS) in this setting are limited.

Objective

To compare postoperative complications in patients undergoing either upfront resection or pancreatectomy following NAT, focusing on clinically relevant postoperative pancreatic fistula (CR-POPF) and potential associations with OS.

Design, Setting, and Participants

This retrospective cohort study was conducted on data from patients who underwent pancreatic resection for PDAC at the Massachusetts General Hospital from January 1, 2007, to December 31, 2017.

Exposures

Pancreatic cancer surgery with or without NAT.

Main Outcomes and Measures

Overall morbidity and CR-POPF rates were compared between NAT and upfront resection. Factors associated with CR-POPF were assessed with univariate and multivariate analysis. Survival data were analyzed by Kaplan-Meier curves and a Cox proportional hazards regression model.

Results

Of 753 patients, 364 were men (48.3%); median (interquartile range) age was 68 (61-75) years. A total of 346 patients (45.9%) received NAT and 407 patients (54.1%) underwent upfront resection. At pathologic examination, NAT was associated with smaller tumor size (mean [SD], 26.0 [15.3] mm vs 32.7 [14.4] mm; P < .001), reduced nodal involvement (102 [25.1%] vs 191 [55.2%]; P < .001), and higher R0 rates (257 [74.3%] vs 239 [58.7%]; P < .001). There were no significant differences in severe complication rate or 90-day mortality. The rate of CR-POPF was 3.6-fold lower in patients receiving NAT vs upfront resection (13 [3.8%] vs 56 [13.8%]; P < .001). In addition, factors associated with CR-POPF changed after NAT, and only soft pancreatic texture was associated with a higher risk of CR-POPF (38.5% vs 6.3%; P < .001). Survival analysis showed no differences between patients with or without CR-POPF after upfront resection (26 vs 25 months; P = .66), but after NAT, a worse overall survival rate was observed in patients with CR-POPF (17 vs 34 months; P = .002). This association was independent of other established predictors of overall survival by multivariate analysis (hazard ratio, 2.80; 95% CI, 1.44-5.45; P < .002).

Conclusions and Relevance

Neoadjuvant therapy may be associated with a significant reduction in the rate of CR-POPF. In addition, standard factors associated with CR-POPF appear to be no longer applicable following NAT. However, once CR-POPF occurs, it is associated with a significant reduction in long-term survival. Patients with CR-POPF may require closer follow-up and could benefit from additional therapy.