Perineural Invasion is an Important Prognostic Factor in Patients With Radically Resected (R0) and Node-negative (pN0) Pancreatic Cancer.

OBJECTIVE: To investigate the association between perineural invasion (PNI) and overall survival (OS) in a nationwide cohort of patients with resected pancreatic ductal adenocarcinoma (PDAC), stratified for margin negative (R0) or positive (R1) resection and absence or presence of lymph node metastasis (pN0 or pN1-N2, respectively). BACKGROUND: Patients with R0 and pN0 resected PDAC have a relatively favorable prognosis. As PNI is associated with worse OS, this might be a useful factor to provide further prognostic information for patients counselling. METHODS: A nationwide observational cohort study was performed including all patients who underwent PDAC resection in the Netherlands (2014-2019) with complete information on relevant pathological features (PNI, R status, and N status). OS was assessed using Kaplan-Meier curves, and Cox-proportional hazard analyses were performed to calculate hazard ratio's (HR) with corresponding 95% confidence intervals (CI). RESULTS: In total, 1630 patients were included with a median follow-up of 43 (interquartile range 33-58) months. PNI was independently associated with worse OS in both R0 patients (HR 1.49 [95%CI 1.18-1.88]; P<0.001) and R1 patients (HR 1.39 [95% CI 1.06-1.83]; P=0.02), as well as in pN0 patients (HR 1.75 [95%CI 1.27-2.41]; P<0.001) and pN1-N2 patients (HR 1.35 [95% CI 1.10-1.67]; P<0.01). In 315 patients with R0N0, multivariable analysis showed that PNI was the strongest predictor of OS (HR 2.24 [95% CI 1.52-3.30]; P<0.001). CONCLUSION: PNI is strongly associated with worse survival in patients with resected PDAC, in particular in patients with relatively favorable pathological features. These findings may aid patient stratification and counselling and help guide treatment strategies.

Evaluation of Short- and Long-Term Outcomes After Resection in Patients with Locally Advanced versus (Borderline) Resectable Pancreatic Cancer.

OBJECTIVE: This study aims to evaluate short- and long-term outcomes following pancreatectomy in patients with LAPC compared to (B)RPC patients. SUMMARY BACKGROUND DATA: Selected patients diagnosed with locally advanced pancreatic cancer (LAPC) are increasingly undergoing resection following induction chemotherapy. To evaluate the benefit of this treatment approach, it is helpful to compare outcomes in resected patients with primary LAPC to outcomes in resected patients with primary (borderline) resectable pancreatic cancer ((B)RPC). METHODS: Two prospectively maintained nationwide databases were used for this study. Patients with (B)RPC undergoing upfront tumor resection and patients with resected LAPC after induction therapy were included. Outcomes were postoperative pancreas-specific complications, 90-day mortality, pathological outcomes, disease-free interval (DFI), and overall survival (OS). RESULTS: Overall, 879 patients were included; 103 with LAPC (12%) and 776 with (B)RPC (88%). LAPC patients had a lower WHO performance score and CACI. Postoperative pancreas-specific complications were comparable between groups, except delayed gastric emptying grade C, which occurred more often in LAPC patients (9% vs. 3%, P=0.03). Ninety-day mortality was comparable. About half of the patients in both groups (54% in LAPC vs. 48% in (B)RPC), P=0.21) had a radical resection (R0). DFI was 13 months in both groups (P=0.12) and OS from date of diagnosis was 24 months in LAPC patients and 19 months in (B)RPC patients (P=0.34). CONCLUSIONS: In our nationwide prospective databases, pancreas-specific complications, mortality and survival in patients with LAPC following pancreatectomy are comparable with those undergoing resection for (B)RPC. These outcomes suggest that postoperative morbidity and mortality after tumor resection in carefully selected patients with LAPC are acceptable.

The Value of Biological and Conditional Factors for Staging of Patients with Resectable Pancreatic Cancer Undergoing Upfront Resection: A Nationwide Analysis.

BACKGROUND: Novel definitions suggest that resectability status for pancreatic ductal adenocarcinoma (PDAC) should be assessed beyond anatomical criteria, considering both biological and conditional factors. This has, however, yet to be validated on a nationwide scale. This study evaluated the prognostic value of biological and conditional factors for staging of patients with resectable PDAC. PATIENTS AND METHODS: A nationwide observational cohort study was performed, including all consecutive patients who underwent upfront resection of National Comprehensive Cancer Network resectable PDAC in the Netherlands (2014-2019) with complete information on preoperative carbohydrate antigen (CA) 19-9 and Eastern Cooperative Oncology Group (ECOG) performance status. PDAC was considered biologically unfavorable (RB+) if CA19-9 ≥ 500 U/mL and favorable (RB-) otherwise. ECOG ≥ 2 was considered conditionally unfavorable (RC+) and favorable otherwise (RC-). Overall survival (OS) was assessed using Kaplan-Meier and Cox-proportional hazard analysis, presented as hazard ratios (HRs) with 95% confidence interval (CI). RESULTS: Overall, 688 patients were analyzed with a median overall survival (OS) of 20 months (95% CI 19-23). OS was 14 months (95% CI 10 months-median not reached) in 20 RB+C+ patients (3%; HR 1.61, 95% CI 0.86-2.70), 13 months (95% CI 11-15) in 156 RB+C- patients (23%; HR 1.86, 95% CI 1.50-2.31), and 21 months (95% CI 12-41) in 47 RB-C+ patients (7%; HR 1.14, 95% CI 0.80-1.62) compared with 24 months (95% CI 22-27) in 465 patients with RB-C- PDAC (68%; reference). CONCLUSIONS: Survival after upfront resection of anatomically resectable PDAC is worse in patients with CA19-9 ≥ 500 U/mL, while performance status had no impact. This supports consideration of CA19-9 in preoperative staging of resectable PDAC.

Predicting Long-term Disease-free Survival After Resection of Pancreatic Ductal Adenocarcinoma: A Nationwide Cohort Study.

OBJECTIVE: To develop a prediction model for long-term (≥5 years) disease-free survival (DFS) after the resection of pancreatic ductal adenocarcinoma (PDAC). BACKGROUND: Despite high recurrence rates, ~10% of patients have long-term DFS after PDAC resection. A model to predict long-term DFS may aid individualized prognostication and shared decision-making. METHODS: This nationwide cohort study included all consecutive patients who underwent PDAC resection in the Netherlands (2014-2016). The best-performing prognostic model was selected by Cox-proportional hazard analysis and Akaike's Information Criterion, presented by hazard ratios (HRs) with 95% confidence intervals (CIs). Internal validation was performed, and discrimination and calibration indices were assessed. RESULTS: In all, 836 patients with a median follow-up of 67 months (interquartile range 51-79) were analyzed. Long-term DFS was seen in 118 patients (14%). Factors predictive of long-term DFS were low preoperative carbohydrate antigen 19-9 (logarithmic; HR 1.21; 95% CI 1.10-1.32), no vascular resection (HR 1.33; 95% CI 1.12-1.58), T1 or T2 tumor stage (HR 1.52; 95% CI 1.14-2.04, and HR 1.17; 95% CI 0.98-1.39, respectively), well/moderate tumor differentiation (HR 1.44; 95% CI 1.22-1.68), absence of perineural and lymphovascular invasion (HR 1.42; 95% CI 1.11-1.81 and HR 1.14; 95% CI 0.96-1.36, respectively), N0 or N1 nodal status (HR 1.92; 95% CI 1.54-2.40, and HR 1.33; 95% CI 1.11-1.60, respectively), R0 resection margin status (HR 1.25; 95% CI 1.07-1.46), no major complications (HR 1.14; 95% CI 0.97-1.35) and adjuvant chemotherapy (HR 1.74; 95% CI 1.47-2.06). Moderate performance (concordance index 0.68) with adequate calibration (slope 0.99) was achieved. CONCLUSIONS: The developed prediction model, readily available at www.pancreascalculator.com, can be used to estimate the probability of long-term DFS after resection of pancreatic ductal adenocarcinoma.

Risk Models for Developing Pancreatic Fistula After Pancreatoduodenectomy: Validation in a Nationwide Prospective Cohort.

OBJECTIVE: To evaluate the performance of published fistula risk models by external validation, and to identify independent risk factors for postoperative pancreatic fistula (POPF). BACKGROUND: Multiple risk models have been developed to predict POPF after pancreatoduodenectomy. External validation in high-quality prospective cohorts is, however, lacking or only performed for individual models. METHODS: A post hoc analysis of data from the stepped-wedge cluster cluster-randomized Care After Pancreatic Resection According to an Algorithm for Early Detection and Minimally Invasive Management of Pancreatic Fistula versus Current Practice (PORSCH) trial was performed. Included were all patients undergoing pancreatoduodenectomy in the Netherlands (January 2018-November 2019). Risk models on POPF were identified by a systematic literature search. Model performance was evaluated by calculating the area under the receiver operating curves (AUC) and calibration plots. Multivariable logistic regression was performed to identify independent risk factors associated with clinically relevant POPF. RESULTS: Overall, 1358 patients undergoing pancreatoduodenectomy were included, of whom 341 patients (25%) developed clinically relevant POPF. Fourteen risk models for POPF were evaluated, with AUCs ranging from 0.62 to 0.70. The updated alternative fistula risk score had an AUC of 0.70 (95% confidence intervals [CI]: 0.69-0.72). The alternative fistula risk score demonstrated an AUC of 0.70 (95% CI: 0.689-0.71), whilst an AUC of 0.70 (95% CI: 0.699-0.71) was also found for the model by Petrova and colleagues. Soft pancreatic texture, pathology other than pancreatic ductal adenocarcinoma or chronic pancreatitis, small pancreatic duct diameter, higher body mass index, minimally invasive resection and male sex were identified as independent predictors of POPF. CONCLUSION: Published risk models predicting clinically relevant POPF after pancreatoduodenectomy have a moderate predictive accuracy. Their clinical applicability to identify high-risk patients and guide treatment strategies is therefore questionable.

Short- and Long-Term Outcomes of Pancreatic Cancer Resection in Elderly Patients: A Nationwide Analysis.

BACKGROUND: The number of elderly patients with pancreatic cancer is growing, however clinical data on the short-term outcomes, rate of adjuvant chemotherapy, and survival in these patients are limited and we therefore performed a nationwide analysis. METHODS: Data from the prospective Dutch Pancreatic Cancer Audit were analyzed, including all patients undergoing pancreatic cancer resection between January 2014 and December 2016. Patients were classified into two age groups: <75 and ≥75 years. Major complications (Clavien-Dindo grade 3 or higher), 90-day mortality, rates of adjuvant chemotherapy, and survival were compared between age groups. Factors associated with start of adjuvant chemotherapy and survival were evaluated with logistic regression and multivariable Cox regression analysis. RESULTS: Of 836 patients, 198 were aged ≥75 years (24%) and 638 were aged <75 years (76%). Median follow-up was 38 months (interquartile range [IQR] 31-47). Major complications (31% vs. 28%; p = 0.43) and 90-day mortality (8% vs. 5%; p = 0.18) did not differ. Adjuvant chemotherapy was started in 37% of patients aged ≥75 years versus 69% of patients aged <75 years (p < 0.001). Median overall survival (OS) was 15 months (95% confidence interval [CI] 14-18) versus 21 months (95% CI 19-24; p < 0.001). Age ≥75 years was not independently associated with OS (hazard ratio 0.96, 95% CI 0.79-1.17; p = 0.71), but was associated with a lower rate of adjuvant chemotherapy (odds ratio 0.27, 95% CI 0.18-0.40; p < 0.001). CONCLUSIONS: The rate of major complications and 90-day mortality after pancreatic resection did not differ between elderly and younger patients; however, elderly patients were less often treated with adjuvant chemotherapy and their OS was shorter.

Nationwide Validation of the 8th American Joint Committee on Cancer TNM Staging System and Five Proposed Modifications for Resected Pancreatic Cancer.

BACKGROUND: The prognostic value of four proposed modifications to the 8th American Joint Committee on Cancer (AJCC) TNM staging system has yet to be evaluated. This study aimed to validate five proposed modifications. METHODS: Patients who underwent pancreatic ductal adenocarcinoma resection (2014-2016), as registered in the prospective Dutch Pancreatic Cancer Audit, were included. Stratification and prognostication of TNM staging systems were assessed using Kaplan-Meier curves, Cox proportional hazard analyses, and C-indices. A new modification was composed based on overall survival (OS). RESULTS: Overall, 750 patients with a median OS of 18 months (interquartile range 10-32) were included. The 8th edition had an increased discriminative ability compared with the 7th edition {C-index 0.59 (95% confidence interval [CI] 0.56-0.61) vs. 0.56 (95% CI 0.54-0.58)}. Although the 8th edition showed a stepwise decrease in OS with increasing stage, no differences could be demonstrated between all substages; stage IIA vs. IB (hazard ratio [HR] 1.30, 95% CI 0.80-2.09; p  = 0.29) and stage IIB vs. IIA (HR 1.17, 95% CI 0.75-1.83; p  = 0.48). The four modifications showed comparable prognostic accuracy (C-index 0.59-0.60); however, OS did not differ between all modified TNM stages (ns). The new modification, migrating T3N1 patients to stage III, showed a C-index of 0.59, but did detect significant survival differences between all TNM stages (p  < 0.05). CONCLUSIONS: The 8th TNM staging system still lacks prognostic value for some categories of patients, which was not clearly improved by four previously proposed modifications. The modification suggested in this study allows for better prognostication in patients with all stages of disease.

Treatment strategies and clinical outcomes in consecutive patients with locally advanced pancreatic cancer: A multicenter prospective cohort.

INTRODUCTION: Since current studies on locally advanced pancreatic cancer (LAPC) mainly report from single, high-volume centers, it is unclear if outcomes can be translated to daily clinical practice. This study provides treatment strategies and clinical outcomes within a multicenter cohort of unselected patients with LAPC. MATERIALS AND METHODS: Consecutive patients with LAPC according to Dutch Pancreatic Cancer Group criteria, were prospectively included in 14 centers from April 2015 until December 2017. A centralized expert panel reviewed response according to RECIST v1.1 and potential surgical resectability. Primary outcome was median overall survival (mOS), stratified for primary treatment strategy. RESULTS: Overall, 422 patients were included, of whom 77% (n = 326) received chemotherapy. The majority started with FOLFIRINOX (77%, 252/326) with a median of six cycles (IQR 4-10). Gemcitabine monotherapy was given to 13% (41/326) of patients and nab-paclitaxel/gemcitabine to 10% (33/326), with a median of two (IQR 3-5) and three (IQR 3-5) cycles respectively. The mOS of the entire cohort was 10 months (95%CI 9-11). In patients treated with FOLFIRINOX, gemcitabine monotherapy, or nab-paclitaxel/gemcitabine, mOS was 14 (95%CI 13-15), 9 (95%CI 8-10), and 9 months (95%CI 8-10), respectively. A resection was performed in 13% (32/252) of patients after FOLFIRINOX, resulting in a mOS of 23 months (95%CI 12-34). CONCLUSION: This multicenter unselected cohort of patients with LAPC resulted in a 14 month mOS and a 13% resection rate after FOLFIRINOX. These data put previous results in perspective, enable us to inform patients with more accurate survival numbers and will support decision-making in clinical practice.