Adjuvant Therapy in Pancreas Cancer: Does It Influence Patterns of Recurrence?

Organ-specific variations in tumor marker dynamics in postoperative pancreatic cancer recurrence: Trends in lung and liver recurrence highlighting biological heterogeneity

BACKGROUND/OBJECTIVES

Although tumor recurrence after surgical resection in pancreatic cancer (PC) is generally considered incurable, it is well-accepted that clinical presentations and outcomes vary according to the recurrent sites (e.g., liver vs. lung recurrence), suggesting a possible biological inhomogeneity of PC recurrence. Understanding the behavior of biological factors, specifically tumor markers (TMs), at different recurrence sites may contribute to individualized treatment strategies. Therefore, this study aimed to compare the dynamics of pre-recurrence TMs at liver and lung recurrence sites.

METHODS

Patients with isolated postoperative liver or lung recurrence as their first recurrence were enrolled. Starting from the recurrence date confirmed by imaging examinations, the values of TMs (carbohydrate antigen 19-9: CA19-9; carcinoembryonic antigen: CEA) were retrospectively evaluated 6 and 3 months before recurrence and at the time of recurrence.

RESULTS

Patients with liver recurrence displayed a significant increase in CA19-9 and CEA levels from as early as 6 months before recurrence. Contrastingly, patients with lung recurrence demonstrated a significant elevation of CA19-9 levels starting from 3 months before recurrence, with no increase in CEA levels, even at the time of recurrence. The relative change in CA19-9 and CEA levels during each period were significantly lower in patients with lung recurrence.

CONCLUSIONS

Both TMs exhibited organ-specific variations in patients with postoperative PC recurrence. This disparity may reflect the biological heterogeneity of PC between recurrence patterns, thereby highlighting the importance of conducting postoperative follow-up with consideration of this fact.

Comparing upfront surgery with neoadjuvant treatments in patients with resectable, borderline resectable or locally advanced pancreatic cancer: a systematic review and network meta-analysis of randomized clinical trials

BACKGROUND

The aim was to explore the optimal neoadjuvant therapy strategy for resectable, borderline resectable, and locally advanced pancreatic cancer, in order to provide a theoretical basis for the development of new neoadjuvant treatment protocols for clinical use.

PATIENTS AND METHODS

The authors reviewed literature titles and abstracts comparing three treatment strategies (neoadjuvant chemoradiotherapy, neoadjuvant chemotherapy, and upfront surgery) in PubMed, Embase, The Cochrane Library, Web of Science from 2009 to 2023 to estimate relative odds ratios for resection rate and hazard ratios (HRs) for overall survival (OS) in all include trials.

RESULTS

A total of nine studies involving 889 patients were included in the analysis. The treatment methods included upfront surgery, neoadjuvant chemotherapy, and neoadjuvant chemoradiotherapy followed by surgery. The network meta-analysis results demonstrated that neoadjuvant chemoradiotherapy followed by surgery was an effective approach in improving OS for resectable and borderline resectable pancreatic cancer (RPC) patients compared to upfront surgery (HR: 0.79, 95% CI: 0.64-0.98) and neoadjuvant chemotherapy (HR: 0.79, 95% CI: 0.64-0.98). Additionally, neoadjuvant chemoradiotherapy significantly increased the margin negative resection (R0) rate and pathological negative lymph node (pN0) rate in patients with resectable and borderline RPC. However, it is worth noting that neoadjuvant chemoradiotherapy increased the risk of grade 3 or higher treatment-related adverse events, including in patients with locally advanced pancreatic cancer.

CONCLUSIONS

The current evidence suggests that neoadjuvant chemoradiotherapy followed by surgery is the optimal choice for treating patients with resectable and borderline RPC. Future research should focus on optimizing neoadjuvant chemoradiotherapy regimens to effectively improve OS while reducing the occurrence of adverse events.

TRIANGLE operation, combined with adequate adjuvant chemotherapy, can improve the prognosis of pancreatic head cancer: A retrospective study

BACKGROUND

The TRIANGLE operation involves the removal of all tissues within the triangle bounded by the portal vein-superior mesenteric vein, celiac axis-common hepatic artery, and superior mesenteric artery to improve patient prognosis. Although previously promising in patients with locally advanced pancreatic ductal adenocarcinoma (PDAC), data are limited regarding the long-term oncological outcomes of the TRIANGLE operation among resectable PDAC patients undergoing pancreaticoduodenectomy (PD).

AIM

To evaluate the safety of the TRIANGLE operation during PD and the prognosis in patients with resectable PDAC.

METHODS

This retrospective cohort study included patients who underwent PD for pancreatic head cancer between January 2017 and April 2023, with or without the TRIANGLE operation. Patients were divided into the PDTRIANGLE and PDnon-TRIANGLE groups. Surgical and survival outcomes were compared between the two groups. Adequate adjuvant chemotherapy was defined as adjuvant chemotherapy ≥ 6 months.

RESULTS

The PDTRIANGLE and PDnon-TRIANGLE groups included 52 and 55 patients, respectively. There were no significant differences in the baseline characteristics or perioperative indexes between the two groups. Furthermore, the recurrence rate was lower in the PDTRIANGLE group than in the PDnon-TRIANGLE group (48.1% vs 81.8%, P < 0.001), and the local recurrence rate of PDAC decreased from 37.8% to 16.0%. Multivariate Cox regression analysis revealed that PDTRIANGLE (HR = 0.424; 95%CI: 0.256-0.702; P = 0.001), adequate adjuvant chemotherapy ≥ 6 months (HR = 0.370; 95%CI: 0.222-0.618; P < 0.001) and margin status (HR = 2.255; 95%CI: 1.252-4.064; P = 0.007) were found to be independent factors for the recurrence rate.

CONCLUSION

The TRIANGLE operation is safe for PDAC patients undergoing PD. Moreover, it reduces the local recurrence rate of PDAC and may improve survival in patients who receive adequate adjuvant chemotherapy.

Molecular pathology and protein markers for pancreatic cancer: relevance in staging, in adjuvant therapy, in determination of minimal residual disease, and follow-up

The diagnosis and monitoring of disease through the detection of circulating protein biomarkers is a growing field in the practice of oncology. The search for more effective protein biomarkers to aid in the diagnosis and treatment of patients with pancreatic ductal adenocarcinoma (PDAC) remains a valuable area of study, given the aggressive and often occult nature of this malignancy. Liquid biopsies are attractive, as they offer a minimally invasive and cost-effective approach when compared to traditional biopsy methods and imaging modalities used for diagnosis and surveillance. Carbohydrate antigen (CA) 19-9 is currently the most commonly used serum protein biomarker for the diagnosis and monitoring of patients with PDAC, but due to its sensitivity and specificity, its utility remains limited. In this review, we examine how circulating protein biomarkers are used in the diagnosis, prognostication, and surveillance of PDAC. We also highlight protein biomarkers that are currently under investigation that have the potential to enhance our ability to detect early-stage malignancies, predict response to therapy, and monitor for recurrence, but these markers require larger prospective validation studies before they can be widely implemented. Continued efforts to identify and validate novel biomarkers will be crucial for improving the management and outcomes of patients with this challenging disease.

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.

Identification of Nectin Family Interactive Gene Panel and Stratification of Clinical Outcomes in Patients with Pancreatic Cancer

BACKGROUND

Although patient-risk stratification is important for selecting individualized treatment for pancreatic ductal adenocarcinoma (PDAC), predicting the oncologic outcomes after surgery remains a challenge. In this study, we identified a nectin family gene panel (NFGP) that can accurately stratify oncologic outcomes in patients with PDAC.

STUDY DESIGN

Comprehensive analysis of the expression of 9 nectin family genes identified the NFGP, which was assessed for predictive performance in 2 independent public cohorts (The Cancer Genome Atlas [TCGA] n = 176; International Cancer Genome Consortium [ICGC] n = 89). It was subsequently trained and validated for the in-house training cohort without neo-adjuvant therapy (NAT, n = 213) and the validation cohort with NAT (n = 307).

RESULTS

Using the Cox regression model, NFGP derived from 9 nectin family genes accurately stratified overall survival (OS) in TCGA (p = 0.038) and ICGC (p = 0.005). We subsequently optimized NFGP, which robustly discriminated postoperative prognosis, OS (p = 0.014) and relapse-free survival ([RFS] p = 0.006) in the training cohort. The NFGP was successfully validated in an independent validation cohort (OS: p < 0.001; RFS: p = 0.004). Multivariate analysis demonstrated the NFGP was an independent prognostic factor for OS and RFS in the training (p = 0.028 and 0.008, respectively) and validation (p < 0.001 and 0.013, respectively) cohorts. The subcohort analyses showed that the predictive performance of NFGP is applicable to the patients' subcohort according to resectability or adjuvant therapy status. Additionally, a combination model of NFGP score and CA19-9 level emerged with improved accuracy for predicting prognosis.

CONCLUSIONS

This study established the predictive significance of NFGP for oncologic outcomes after surgery in PDAC. Our data demonstrate its clinical impact as a potent biomarker for optimal patient selection for individualized treatment strategies.

Peritoneal Cell-Free Tumor DNA is a Biomarker of Locoregional and Peritoneal Recurrence in Resected Pancreatic Ductal Adenocarcinomas

BACKGROUND

Recurrence after curative-intent pancreatectomy for pancreatic ductal adenocarcinomas (PDAC) is quite frequent with locoregional and peritoneal recurrence in about one-third of cases. We hypothesize that peritoneal cell-free tumor DNA (ptDNA) present in the intraoperative peritoneal lavage (PL) fluid may be used as a predictive biomarker of locoregional and peritoneal recurrence.

PATIENTS AND METHODS

Under institutional review board (IRB)-approved protocol, pre- and postresection PL fluids were collected from PDAC patients undergoing curative-intent pancreatectomy. PL fluids from PDAC patients with pathologically proven peritoneal metastasis were also collected as positive controls. Cell-free DNA was extracted from PL fluids. Droplet digital PCR (ddPCR) was performed using ddPCR KRAS G12/G13 screening kit. Recurrence-free survival (RFS) based on KRAS-mutant ptDNA level was determined using Kaplan-Meier methods.

RESULTS

KRAS-mutant ptDNA was detected in PL fluids from all PDAC patients. KRAS-mutant ptDNA was detected in 11/21 (52%) preresection and 15/18 (83%) postresection PL fluid samples. With a median follow-up of 23.6 months, 12 patients developed recurrence (8 locoregional/peritoneal recurrence, 9 pulmonary/hepatic recurrence); 5/8 (63%) and 6/6 (100%) patients with mutant allele frequency (MAF) of > 0.10% in pre- and postresection PL fluids, respectively, developed recurrence. Using a cutoff value of 0.10% MAF, the presence of KRAS-mutant ptDNA in postresection PL fluid predicted a significantly shortened time to locoregional and peritoneal recurrence (median RFS of 8.9 months versus not reached, P = 0.003).

CONCLUSIONS

This study suggests that ptDNA in postresection PL fluids may be a useful biomarker to predict locoregional and peritoneal recurrence in resected PDAC patients.

Cancer "Avatars": Patient-Derived Xenograft Growth Correlation with Postoperative Recurrence and Survival in Pancreaticobiliary Cancer

BACKGROUND

Pancreaticobiliary (PB) cancers are a diverse group of cancers with poor prognoses and high rates of recurrence after resection. Patient-derived xenografts (PDX), created from surgical specimens, provide a reliable preclinical research platform and high-fidelity cancer model from which to study these malignancies with consistent recapitulation of their original patient tumors in vivo. However, the relationship between PDX engraftment success (growth or no growth) and patient oncologic outcomes has not been well studied. We sought to evaluate the correlation between successful PDX engraftment and survival in several PB exocrine carcinomas, including the pancreatic and biliary tract.

STUDY DESIGN

In accordance with IRB and Institutional Animal Care and Use Committee protocols and with appropriate consent and approval, excess tumor tissue obtained from surgical patients was implanted into immunocompromised mice. Mice were monitored for tumor growth to determine engraftment success. PDX tumors were verified to recapitulate their tumors of origin by a hepatobiliary pathologist. Xenograft growth was correlated with clinical recurrence and overall survival data.

RESULTS

A total of 384 PB xenografts were implanted. The successful engraftment rate was 41% (158/384). We found that successful PDX engraftment was highly associated with both recurrence-free survival (p < 0.001) and overall survival (p < 0.001) outcomes. Successful PDX tumor generation occurs significantly in advance of clinical recurrences in their corresponding patients (p < 0.001).

CONCLUSIONS

Successful PB cancer PDX models predict recurrence and survival across tumor types and may provide critical lead time to alter patients' surveillance or treatment plans before cancer recurrence.

Photodynamic Stromal Depletion in Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest solid malignancies, with a five-year survival of less than 10%. The resistance of the disease and the associated lack of therapeutic response is attributed primarily to its dense, fibrotic stroma, which acts as a barrier to drug perfusion and permits tumour survival and invasion. As clinical trials of chemotherapy (CT), radiotherapy (RT), and targeted agents have not been successful, improving the survival rate in unresectable PDAC remains an urgent clinical need. Photodynamic stromal depletion (PSD) is a recent approach that uses visible or near-infrared light to destroy the desmoplastic tissue. Preclinical evidence suggests this can resensitise tumour cells to subsequent therapies whilst averting the tumorigenic effects of tumour-stromal cell interactions. So far, the pre-clinical studies have suggested that PDT can successfully mediate the destruction of various stromal elements without increasing the aggressiveness of the tumour. However, the complexity of this interplay, including the combined tumour promoting and suppressing effects, poses unknowns for the clinical application of photodynamic stromal depletion in PDAC.

The impact of resection margin distance on survival and recurrence in pancreatic ductal adenocarcinoma in a retrospective cohort analysis

BACKGROUND

The prognostic effect of resection margin status following pancreatoduodenectomy for pancreatic ductal adenocarcinoma (PDAC) remains controversial, even with the implementation of standardized pathological assessment. We therefore investigated the impact of resection margin (RM) status and RM distance in curative resected PDAC on overall survival (OS), disease-free survival (DFS) and recurrence.

METHOD

108 patients were retrieved from a prospectively maintained database of a certified pancreatic cancer center. Distribution and relationships between circumferential resection margin (CRM) involvement (CRM≤1mm; CRM>1mm; CRM≥2mm) and their prognostic impact on OS and DFS were assessed using Kaplan-Meier statistics and the Log-Rank test. Multivariate logistic regression was used explain the development of a recurrence 12 months after surgery.

RESULTS

63 out of 108 patients had medial RM and 32 posterior RM involvement. There was no significant difference in OS and DFS between CRM≤1mm and CRM>1mm resections. Clearance at the medial margin of ≥2mm had an impact on OS and DFS, (RM≥2mm vs. RM<2mm: median OS 29.8 vs 16.8 months, median DFS 19.6 vs. 10.3 months). Multivariate analysis demonstrated that age, medial RM ≥2mm, lymph node status and chemotherapy were prognostic factors for OS and DFS. Posterior RM had no influence on OS or DFS.

CONCLUSION

Not all RM seem to have the same impact on OS and DFS, and a clearance of 1mm for definition of a negative RM (i.e. CRM>1mm) seems not sufficient. Future studies should include more patients to stratify for potential confounders we could not account for.

TRIAL REGISTRATION

This study was registered with the German Clinical Trials Registry (reference number DRKS0017425).

Current Treatment of Potentially Resectable Pancreatic Ductal Adenocarcinoma: A Medical Oncologist's Perspective

Pancreatic cancer has traditionally been associated with a dismal prognosis, even in early stages of the disease. In recent years, the introduction of newer generation chemotherapy regimens in the adjuvant setting has improved the survival of patients treated with upfront resection. However, there are multiple theoretical advantages to deliver early systemic therapy in patients with localized pancreatic cancer. So far, the evidence supports the use of neoadjuvant therapy for patients with borderline resectable pancreatic cancer. The benefit of this treatment sequence for patients with resectable disease remains elusive. In this review, we summarize the data on adjuvant therapy for pancreatic cancer and describe which evidence backs the use of neoadjuvant therapy. Additionally, we address important issues faced in clinical practice when treating patients with localized pancreatic cancer.

Clinical significance and functional role of adhesion G-protein-coupled receptors in human pancreatic ductal adenocarcinoma

BACKGROUND

The adhesion G-protein-coupled receptors (GPCRs) play crucial roles in tumour pathogenesis, however, their clinical significance in pancreatic ductal adenocarcinoma (PDAC) remains unclear.

METHODS

We analysed 796 PDAC patients, including 331 from public data sets (TCGA, ICGC and GSE57495) and 465 from independent cohorts (training: n = 321, validation: n = 144). Using in-vitro studies, we confirmed the biological function of the candidate GPCRs.

RESULTS

Analysis of all 33 adhesion GPCRs, led to identify GPR115, as the only significant prognostic factor in all public data sets. The patients with high GPR115 expression exhibited significantly poorer prognosis for OS and RFS, in training (P < 0.01, P < 0.01) and validation cohort (P < 0.01, P = 0.04). Multivariate analysis indicated that GPR115 high expression was an independent prognostic factor in both cohorts (HR = 1.43; P = 0.01, HR = 2.55; P < 0.01). A risk-prediction model using Cox regression by incorporating GPR115 and clinicopathological factors accurately predicted 5-year survival following surgery. In addition, GPR115 silencing inhibited cell proliferation and migration in PDAC cells.

CONCLUSION

We demonstrated that GPR115 has important prognostic significance and functional role in tumour progression; providing a rationale that this may be a potential therapeutic target in patients with PDAC.

Transcriptomic Profiling Identifies an Exosomal microRNA Signature for Predicting Recurrence Following Surgery in Patients With Pancreatic Ductal Adenocarcinoma

OBJECTIVE

We performed genome-wide expression profiling to develop an exosomal miRNA panel for predicting recurrence following surgery in patients with PDAC.

SUMMARY OF BACKGROUND DATA

Pretreatment risk stratification is essential for offering individualized treatments to patients with PDAC, but predicting recurrence following surgery remains clinically challenging.

METHODS

We analyzed 210 plasma and serum specimens from 4 cohorts of PDAC patients. Using a discovery cohort (n = 25), we performed genome-wide sequencing to identify candidate exosomal miRNAs (exo-miRNAs). Subsequently, we trained and validated the predictive performance of the exo-miRNAs in two clinical cohorts (training cohort: n = 82, validation cohort: n = 57) without neoadjuvant therapy (NAT), followed by a post-NAT clinical cohort (n = 46) as additional validation.

RESULTS

We performed exo-miRNA expression profiling in plasma specimens obtained before any treatment in a discovery cohort. Subsequently we optimized and trained a 6-exo-miRNA risk-prediction model, which robustly discriminated patients with recurrence [area under the curve (AUC): 0.81, 95% confidence interval (CI): 0.70-0.89] and relapse-free survival (RFS, P < 0.01) in the training cohort. The identified exo-miRNA panel was successfully validated in an independent validation cohort (AUC: 0.78, 95% CI: 0.65- 0.88, RFS: P < 0.01), where it exhibited comparable performance in the post-NAT cohort (AUC: 0.72, 95% CI: 0.57-0.85, RFS: P < 0.01) and emerged as an independent predictor for RFS (hazard ratio: 2.84, 95% CI: 1.30-6.20).

CONCLUSIONS

We identified a novel, noninvasive exo-miRNA signature that robustly predicts recurrence following surgery in patients with PDAC; highlighting its potential clinical impact for optimized patient selection and improved individualized treatment strategies.

A nationwide randomized controlled trial on additional treatment for isolated local pancreatic cancer recurrence using stereotactic body radiation therapy (ARCADE)

BACKGROUND

Disease recurrence is the main cause of mortality after resection of pancreatic ductal adenocarcinoma (PDAC). In 20-30% of resected patients, isolated local PDAC recurrence occurs. Retrospective studies have suggested that stereotactic body radiation therapy (SBRT) might lead to improved local control in these patients, potentially having a beneficial effect on both survival and quality of life. The "nationwide randomized controlled trial on additional treatment for isolated local pancreatic cancer recurrence using stereotactic body radiation therapy" (ARCADE) will investigate the value of SBRT in addition to standard of care in patients with isolated local PDAC recurrence compared to standard of care alone, regarding both survival and quality of life outcomes.

METHODS

The ARCADE trial is nested within a prospective cohort (Dutch Pancreatic Cancer Project; PACAP) according to the 'Trials within Cohorts' design. All PACAP participants with isolated local PDAC recurrence after primary resection who provided informed consent for being randomized in future studies are eligible. Patients will be randomized for local therapy (5 fractions of 8 Gy SBRT) in addition to standard of care or standard of care alone. In total, 174 patients will be included. The main study endpoint is survival after recurrence. The most important secondary endpoint is quality of life.

DISCUSSION

It is hypothesized that additional SBRT, compared to standard of care alone, improves survival and quality of life in patients with isolated local recurrence after PDAC resection.

TRIAL REGISTRATION

ClinicalTrials.gov registration NCT04881487 . Registered on May 11, 2021.

Analysis of preoperative risk factors for early recurrence after curative pancreatoduodenectomy for resectable pancreatic adenocarcinoma

Objectives

To investigate the risk factors for early recurrence after curative pancreatoduodenectomy for resectable pancreatic ductal adenocarcinoma.

Methods

All data were retrospectively collected from patients with resectable pancreatic ductal adenocarcinoma who had undergone pancreatoduodenectomy at the Department of Surgery, Phramongkutklao Hospital, from January 2015 to December 2020. The preoperative and perioperative risk factors were included into the analysis.

Results

In total, 34 patients were included in the study. The median time for recurrence and median survival time were 17 and 20 months, respectively. The 1, 3, and 5 year disease-free survival rates were 59.6%, 23.87%, and 23.87%, respectively, while the 1, 3, and 5 year overall survival rates were 81%, 24.7%, and 12.4%, respectively. Seventeen patients (50%) from a total of 34 patients had recurrence, and ten patients (29.41%) had recurrence within 12 months. The independent preoperative risk factor associated with adverse disease-free survival was tumor size > 4 cm (hazard ratio [HR], 14.34, p=0.022). The perioperative risk factors associated with adverse disease-free survival were pathological lymphovascular invasion (HR, 4.31; p=0.048) and non-hepatopancreatobiliary surgeon (HR, 5.9; p=0.022). Risk factors associated with poor overall survival were microscopical margin positive (R1) resection (HR, 3.68; p=0.019) and non-hepatopancreatobiliary surgeon (HR, 3.45; p=0.031).

Conclusions

Tumor size > 4 cm from the preoperative imaging study was a poor prognostic factor for early recurrence after curative pancreatoduodenectomy for resectable pancreatic adenocarcinoma indicated that they may have radiological occult metastasis, thus, staging laparoscopy may reduce the number of unnecessary laparotomies and avoid missing radiologically negative metastases.

KRAS mutation allele frequency threshold alters prognosis in right-sided resected pancreatic cancer

BACKGROUND

Next-generation sequencing (NGS) provides information on genetic mutations and mutant allele frequency in tumor specimens. We investigated the prognostic significance of KRAS mutant allele frequency in patients with right-sided pancreatic ductal adenocarcinoma (PDAC) treated with surgical resection.

METHODS

A retrospective study reviewed patients who underwent surgical resection for PDAC and analyzed tumors with an in-house mutational panel. Microdissected samples were studied using an NGS-based assay to detect over 200 hotspot mutations in 42 genes (Pan42) commonly involved in PDAC.

RESULTS

A total of 144 PDAC right-sided surgical patients with a Pan42 panel were evaluated between 2015 and 2020; 121 patients (84%) harbored a KRAS mutation. Detected mutant allele frequencies were categorized as less than 20% (low mKRAS, n = 92) or greater than or equal to 20% (high mKRAS, n = 29). High mKRAS (KRAS ≥ 20%) patients were noted to have shorter disease-free survival after surgery (11.5 ± 2.1 vs. 19.5 ± 3.5 months, p = 0.03), more advanced tumor stage (p = 0.02), larger tumors (3.6 vs. 2.7 cm, p = 0.001), greater tumor cellularity (26% vs. 18%, p = 0.001), and higher rate of distant recurrence (p = 0.03) than low mKRAS patients.

CONCLUSION

This study demonstrates the importance of KRAS mutant allele frequency on pathological characteristics and prognosis in right-sided PDAC treated with surgery.

A predictive model for recurrence after upfront surgery in patients with resectable pancreatic ductal adenocarcinoma (PDAC) by using preoperative clinical data and CT characteristics

BACKGROUND

The overall survival for patients with resectable PDAC following curative surgical resection hasn't been improved significantly, as a considerable proportion of patients develop recurrence within a year. The purpose of this study was to develop and validate a predictive model to assess recurrence risk in patients with PDAC after upfront surgery by using preoperative clinical data and CT characteristics.

METHODS

The predictive model was developed based on a retrospective set of 141 pancreatic cancer patients after surgery. A separate set of 77 patients was used to validate model. Between January 2017 and December 2019, all patients underwent multidetector pancreatic CT and upfront surgery. Univariable and multivariate Cox regression was used to determine the risk factors related to recurrence and then establish a nomogram to estimate the 1-year recurrence probability. The Harrell C-index was employed in evaluating the discrimination and calibration of the model.

RESULTS

A total of 218 patients in this retrospective cohort. A recurrence model in nomogram form was developed with predictors including tumor size (hazard ratio [HR], 1.277; 95% CI 1.098, 1.495; P = 0.002), tumor density in the portal vein phase (HR, 0.598; 95% CI 0.424, 0.844; P = 0.003), peripancreatic infiltration (HR, 4.151; 95% CI 2.077, 8.298; P < 0.001), suspicious metastatic lymph node (HR, 2.561; 95% CI 1.653, 3.967; P < 0.001), Neutrophils/Lymphocytes ratio (HR, 1.111; 95% CI 1.016, 1.215; P = 0.020). The predictive nomogram had good discrimination capability with these predictors with an area under curve at 1 year of 0.84 (95%CI 0.77, 0.91) in the development set and 0.82 (95% CI 0.72, 0.92) and 0.84 (95% CI 0.74, 0.94) in the validation set for two radiologists reading respectively.

CONCLUSIONS

The model developed based on preoperative clinical data and CT characteristics of resectable pancreatic ductal adenocarcinoma patients, which can helpfully estimate the recurrence-free survival. It may be a useful tool for clinician to select optimal candidates for upfront surgery or neoadjuvant therapy.

Impact of spatio-temporal recurrence pattern on overall survival for invasive intraductal papillary mucinous neoplasia - A comparison with pancreatic ductal adenocarcinoma

BACKGROUND

Resections for intraductal papillary mucinous neoplasia (IPMN) have increased dramatically during the last decade. Recurrence pattern and impact of adjuvant chemotherapy for solid pancreatic ductal adenocarcinoma (PDAC) is well known, but not for invasive IPMN (inv-IPMN).

OBJECTIVES

To elucidate the impact of spatio-temporal recurrence pattern and adjuvant chemotherapy on overall survival for inv-IPMN compared with PDAC.

METHODS

We conducted a retrospective single-center observational study of consecutive patients ≥18 years of age who underwent resection for inv-IPMN or PDAC at Karolinska University Hospital, between 2009 and 2018. Different initial recurrence sites and time frames as well as predictors for death were assessed with multivariable Cox and logistic regressions. Survival analyses were performed using the Kaplan-Meier model and log rank test.

RESULTS

Of 396 resected patients, 92 were inv-IPMN and 304 PDAC. Both recurrence rate and death rate within three-years were lower for inv-IPMN compared to PDAC (p = 0.006 and p = 0.007 respectively). Across the whole cohort, the most common recurrence patterns were multi-site (25%), single-site liver (21%) and single-site locoregional (10%) recurrence. The most prominent predictors for death in multivariable Cox regression, especially if occurred within the first year, were multi-site (HR 17.0), single-site peritoneal (HR 13.6) and single-site liver (HR 13.1) recurrence. These predictors were less common in inv-IPMN compared to PDAC (p = 0.007). The effect of adjuvant chemotherapy was similar in the two groups.

CONCLUSION

Resected inv-IPMN exhibits a less aggressive recurrence pattern than PDAC that translates into a more favorable overall survival.

The Addition of Chemoradiation to Adjuvant Chemotherapy is Associated With Improved Survival Following Upfront Surgical Resection for Pancreatic Cancer With Nodal Metastases

BACKGROUND

It is unclear whether the addition of chemoradiation (CRT) to adjuvant chemotherapy (CT) following upfront resection of pancreatic ductal adenocarcinoma (PDAC) provides any benefit. While some studies have suggested a benefit to combined modality therapy (CMT) (adjuvant CT plus CRT), it is not clear if this benefit was related to increased CT usage in patients who received CMT. We sought to clarify the use of CMT in patients who underwent upfront resection of PDAC.

METHODS

Patients with non-metastatic PDAC were retrospectively identified from the linked SEER-Medicare database. Those who underwent upfront resection were identified and divided into two cohorts - patients who received adjuvant CT and patients who received adjuvant CMT. Cohorts were compared. Univariate analysis described patient characteristics. Kaplan-Meier and multivariable Cox proportional hazards modeling were used to estimate overall survival (OS).

RESULTS

3555 patients were identified; 856 (24%) received CT and 573 (16%) received CMT. The median number of CT doses was 11 for both groups. Patients who received CMT were younger, diagnosed in the earlier time frame, and had fewer comorbidities. The median OS was 21 months and 18 months for those treated with CMT and CT (P < .0001), respectively, but when stratified by nodal status, the association with improved OS in the CMT cohort was only observed in node-positive patients. On multivariable analysis, receipt of CMT and removal of >15 lymph nodes decreased the risk of death (P < .05).

DISCUSSION

Receipt of CMT following upfront resection for PDAC was associated with improved survival, which was confined to node-positive patients. The role of adjuvant CMT in PDAC with nodal metastases warrants further study.

Preoperative serum carbohydrate antigen 19-9 levels predict early recurrence after the resection of early-stage pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is a serious disease with a poor prognosis. Only a minority of patients undergo surgery due to the advanced stage of the disease, and patients with early-stage disease, who are expected to have a better prognosis, often experience recurrence. Thus, it is important to identify the risk factors for early recurrence and to develop an adequate treatment plan.

AIM

To evaluate the predictive factors associated with the early recurrence of early-stage PDAC.

METHODS

This study enrolled 407 patients with stage I PDAC undergoing upfront surgical resection between January 2000 and April 2016. Early recurrence was defined as a diagnosis of recurrence within 6 mo of surgery. The optimal cutoff values were determined by receiver operating characteristic (ROC) analyses. Univariate and multivariate analyses were performed to identify the risk factors for early recurrence.

RESULTS

Of the 407 patients, 98 patients (24.1%) experienced early disease recurrence: 26 (26.5%) local and 72 (73.5%) distant sites. In total, 253 (62.2%) patients received adjuvant chemotherapy. On ROC curve analysis, the optimal cutoff values for early recurrence were 70 U/mL and 2.85 cm for carbohydrate antigen 19-9 (CA 19-9) levels and tumor size, respectively. Of the 181 patients with CA 19-9 level > 70 U/mL, 59 (32.6%) had early recurrence, compared to 39 (17.4%) of 226 patients with CA 19-9 level ≤ 70 U/mL (P < 0.001). Multivariate analysis revealed that CA 19-9 level > 70 U/mL (P = 0.006), tumor size > 2.85 cm (P = 0.004), poor differentiation (P = 0.008), and non-adjuvant chemotherapy (P = 0.025) were significant risk factors for early recurrence in early-stage PDAC.

CONCLUSION

Elevated CA 19-9 level (cutoff value > 70 U/mL) can be a reliable predictive factor for early recurrence in early-stage PDAC. As adjuvant chemotherapy can prevent early recurrence, it should be recommended for patients susceptible to early recurrence.

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.

Adjuvant Chemotherapy in the Treatment of Intraductal Papillary Mucinous Neoplasms of the Pancreas: Systematic Review and Meta-Analysis

Background

The present systematic review aimed to compare survival outcomes of invasive intraductal papillary mucinous neoplasms (IIPMNs) treated with adjuvant chemotherapy versus surgery alone and to identify pathologic features that may predict survival benefit from adjuvant chemotherapy.

Method

A systematic search of MEDLINE, PubMed, Scopus, and EMBASE was performed using the PRISMA framework. Studies comparing adjuvant chemotherapy and surgery alone for patients with IIPMNs were included. Primary endpoint was overall survival (OS). A narrative synthesis was performed to identify pathologic features that predicted survival benefits from adjuvant chemotherapy.

Results

Eleven studies and 3393 patients with IIPMNs were included in the meta-analysis. Adjuvant chemotherapy significantly reduced the risk of death in the overall cohort (HR 0.57, 95% CI 0.38–0.87, p = 0.009) and node-positive patients (HR 0.29, 95% CI 0.13–0.64, p = 0.002). Weighted median survival difference between adjuvant chemotherapy and surgery alone in node-positive patients was 11.6 months (95% CI 3.83–19.38, p = 0.003) favouring chemotherapy. Adjuvant chemotherapy had no impact on OS in node-negative patients (HR 0.53, 95% CI 0.20–1.43, p = 0.209). High heterogeneity (I² > 75%) was observed in pooled estimates of hazard ratios. Improved OS following adjuvant chemotherapy was reported for patients with stage III/IV disease, tumour size > 2 cm, node-positive status, grade 3 tumour differentiation, positive margin status, tubular carcinoma subtype, and presence of perineural or lymphovascular invasion.

Conclusion

Adjuvant chemotherapy was associated with improved OS in node-positive IIPMNs. However, the findings were limited by marked heterogeneity. Future large multicentre prospective studies are needed to confirm these findings and explore additional predictors of improved OS to guide patient selection for adjuvant chemotherapy.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00268-021-06309-8.

Early administration of amatuximab, a chimeric high-affinity anti-mesothelin monoclonal antibody, suppresses liver metastasis of mesothelin-expressing pancreatic cancer cells and enhances gemcitabine sensitivity in a xenograft mouse model

Amatuximab is a promising therapeutic antibody targeting mesothelin, a 40-kDa glycoprotein that is highly expressed in pancreatic cancer. We investigated the effectiveness of early amatuximab treatment, imitating an adjuvant chemotherapy setting, and combination therapy with amatuximab and gemcitabine in liver metastasis of pancreatic cancer. Liver metastasis mouse models were established in 8-week-old male BALB/c nu/nu mice using the hemisplenic injection method. Tridaily amatuximab monotherapy or combination with gemcitabine was administered to the liver metastasis mouse model before metastatic lesions had formed huge masses. Gaussia luciferase-transfected AsPC-1 was used as a mesothelin-overexpressing pancreatic cancer cell line. The amount of liver metastases and the serum luciferase activity were significantly lower in the treatment groups than those in the control IgG group. Notably, the anti-tumor activity of gemcitabine was synergically enhanced by combination therapy with amatuximab. Furthermore, western blotting revealed that the high expression of phosphorylated c-Met and AKT in liver metastatic lesions treated with gemcitabine monotherapy was canceled by its combination with amatuximab. This result indicated that the observed synergic therapeutic effect may have occurred as a result of the inhibitory effect of amatuximab on the phosphorylation of c-Met and AKT, which were promoted by exposure to GEM. In conclusion, our study revealed that early administration of amatuximab alone or in combination with GEM significantly suppressed the liver metastases of mesothelin-expressing pancreatic cancer cells. A phase II clinical trial of amatuximab as part of an adjuvant chemotherapy regimen for resected pancreatic cancer is expected.

A Risk Score Model for Locoregional Recurrence Following Upfront Surgery for Pancreatic Adenocarcinoma: Implications for Adjuvant Therapy

AIMS

The aims of the study were to identify predictors of locoregional failure (LRF) following surgery for pancreatic adenocarcinoma, develop a prediction risk score model of LRF and evaluate the impact of postoperative radiation therapy (PORT) on LRF.

MATERIALS AND METHODS

A retrospective review was conducted on patients with stages I-III pancreatic adenocarcinoma who underwent surgery at our institution (2005-2016). Univariable and then multivariable analyses were used to evaluate clinicopathological factors associated with LRF for patients who did not receive PORT. The risk score of LRF was calculated based on the sum of coefficients of the predictors of LRF. The model was applied to the entire cohort to evaluate the impact of PORT on the high- and low-risk groups for LRF.

RESULTS

In total, 467 patients were identified (median follow-up 22 months). Among patients who did not receive PORT (n = 440), predictors of LRF were pN+, involved or close ≤1 mm margin(s), moderately and poorly differentiated tumour grade and lymphovascular invasion. After adding patients who received PORT, the 2-year LRF in the high-risk group was 57% for patients who did not receive PORT (n = 242) and 32% among patients who received PORT (n = 22), with an absolute benefit to LRF of 25% (95% confidence interval 5-52%, P = 0.07). The 2-year overall survival for the high-versus the low-risk group was 36% versus 67% (P < 0.001).

CONCLUSION

This risk group classification could be used to identify pancreatic adenocarcinoma patients with higher risk of LRF who may benefit from PORT. However, validation and prospective evaluation are warranted.

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.

Oncologic Impact of Local Recurrence in Resected Pancreatic Cancer and Topographic Preference in Local Recurrence Patterns According to Tumor Location

OBJECTIVES

The objective of this study was to investigate the pattern and the oncologic impact of local recurrence after surgical resection of pancreatic cancer.

METHODS

From July 1992 to December 2016, 388 patients who underwent curative-intent surgery for pancreatic ductal adenocarcinoma were retrospectively reviewed.

RESULTS

At a median follow-up of 29.0 months, 286 (73.7%) of the 367 patients experienced recurrence, and the 5-year overall survival rate was 31.3%. The first recurrence pattern was local in 83 patients (22.0%), systemic in 152 patients (40.2%), and locosystemic in 51 patients (13.5%). There was no difference in overall survival between the patients who had either local or systemic recurrence (P > 0.05). Remnant pancreas, common hepatic artery, celiac trunk, and para-aortic area were the common local recurrence sites in both head and body/tail cancer. However, the superior mesenteric artery (P = 0.050) and portal vein (P = 0.001) were more frequent local recurrence sites for a head tumor, and the surgical bed was a common recurrence site for body/tail tumor (P < 0.001).

CONCLUSIONS

Our study shows the importance of local recurrence on overall survival and that preferred sites of local recurrence according to tumor location are predictable.

Patterns of Failure After Adjuvant Stereotactic Body Radiation Therapy for Pancreatic Cancer With Close or Positive Margins

Purpose

There is no consensus on treatment volumes for adjuvant stereotactic body radiation therapy (SBRT) for pancreatic cancer. Herein, we report patterns of failure after pancreatic SBRT for close/positive margins, which may inform target volume design.

Methods and Materials

An institutional review board-approved retrospective review of patients with pancreatic adenocarcinoma treated with adjuvant SBRT for close/positive margins from 2009 to 2018 was conducted. Patterns of failure were defined as local (LF) within the tumor bed, regional (RF) within lymph nodes or anastomoses, or distant (DF). The cumulative incidence of locoregional failure was calculated using the cumulative incidence function accounting for the competing risk of death. LFs were mapped to the planning target volume (PTV) and classified as in-field (completely within the PTV), marginal (partially within the PTV), or out-of-field (completely outside the PTV). The location of LFs was compared with the Radiation Therapy Oncology Group 0848 contouring atlas to determine whether standard postoperative radiation therapy volumes would have included the LF.

Results

Seventy-six patients were treated with adjuvant SBRT for close (51.3%) or positive (48.7%) margins. Most (81.6%) received 36 Gy in 3 fractions, with a median PTV volume of 17.8 cc (interquartile range, 12.1-25.6). With a median follow-up of 17.0 months (interquartile range, 7.3-28.4), crude rates of first isolated LF, isolated RF, and DF +/- LF or RF were 9.2%, 6.6%, and 56.6%, respectively. Two-year cumulative incidences of LF, RF, locoregional failure, and DF were 34.9%, 30.8%, 49.2%, and 60.4%, respectively. Of 28 reviewable LFs, 21.4% were in-field while the remainder were completely outside (60.7%) or partially outside (17.9%) the PTV. Most LFs (92.9%) would have been encompassed by the Radiation Therapy Oncology Group consensus target volumes.

Conclusions

After adjuvant pancreatic SBRT for close/positive margins, the majority of LFs were outside the PTV but within contemporary target volumes for conventional radiation therapy.

Completion of adjuvant therapy in patients with resected pancreatic cancer

BACKGROUND

Adjuvant chemotherapy is the standard of care for resected pancreatic ductal adenocarcinoma (PDAC). It is estimated that only 40-80% eligible patients initiate intended adjuvant chemotherapy. Completion rates are largely unknown.

METHODS

A retrospective analysis of outcomes of patients with resected PDAC over an 8-year period at H. Lee Moffitt Cancer Center (MCC) was performed.

RESULTS

From a total of 309 patients, 299 were included for further analysis. 242 (81%) initiated adjuvant therapy (AT) and 195 (65%) completed the intended course. The median time-to-initiation of AT was 53 days (7.6 weeks). The most common reasons for early discontinuation of AT (n = 47) were toxicity (n = 29), disease recurrence (n = 9), patient decision (n = 4), unrelated comorbidities (n = 3), and death (n = 1). Completion of AT was an independent predictor of overall survival (OS) and recurrence-free survival (RFS) on multivariable analysis (OS: HR 0.41, CI 0.27-0.61, p < 0.001; RFS: HR 0.52, CI 0.36-0.76, p < 0.001). Factors associated with early termination of AT were vascular resection (OR 0.29, CI 0.13-0.67, p = 0.004) and administration of AT with local oncologist as opposed to MCC (OR 0.41, CI 0.21-0.82, p = 0.010).

CONCLUSION

Completion of AT is associated with improved survival in patients with resected PDAC. Factors associated with an inability to complete AT include vascular resection and administration of AT with local care team in the patient's community.

Defining and Predicting Early Recurrence in 957 Patients With Resected Pancreatic Ductal Adenocarcinoma

OBJECTIVES

To establish an evidence-based cut-off to differentiate between early and late recurrence and to compare clinicopathologic risk factors between the two groups.

SUMMARY BACKGROUND DATA

A clear definition of "early recurrence" after pancreatic ductal adenocarcinoma resection is currently lacking.

METHODS

Patients undergoing pancreatectomy for pancreatic ductal adenocarcinoma between 2000 and 2013 were included. Exclusion criteria were neoadjuvant therapy and incomplete follow-up. A minimum P-value approach was used to evaluate the optimal cut-off value of recurrence-free survival to divide the patients into early and late recurrence cohorts based on subsequent prognosis. Potential risk factors for early recurrence were assessed with logistic regression models.

RESULTS

Of 957 included patients, 204 (21.3%) were recurrence-free at last follow-up. The optimal length of recurrence-free survival to distinguish between early (n = 388, 51.5%) and late recurrence (n = 365, 48.5%) was 12 months (P < 0.001). Patients with early recurrence had 1-, and 2-year post-recurrence survival rates of 20 and 6% compared with 45 and 22% for the late recurrence group (both P < 0.001). Preoperative risk factors for early recurrence included a Charlson age-comorbidity index ≥4 (OR 1.65), tumor size > 3.0 cm on computed tomography (OR 1.53) and CA 19-9 > 210 U/mL (OR 2.30). Postoperative risk factors consisted of poor tumor differentiation grade (OR 1.66), microscopic lymphovascular invasion (OR 1.70), a lymph node ratio > 0.2 (OR 2.49), and CA 19-9 > 37 U/mL (OR 3.38). Adjuvant chemotherapy (OR 0.28) and chemoradiotherapy (OR 0.29) were associated with a reduced likelihood of early recurrence.

CONCLUSION

A recurrence-free interval of 12 months is the optimal threshold for differentiating between early and late recurrence, based on subsequent prognosis.

A Quantitative Clinicopathological Signature for Predicting Recurrence Risk of Pancreatic Ductal Adenocarcinoma After Radical Resection

Recurrence and distant metastases were main reasons of unfavorable outcomes for patients with pancreatic ductal adenocarcinoma (PDAC) after surgery. The aim of this study was to describe the patterns, timing, and predictors of recurrence or metastasis in PDAC patients after curative surgery. Patients with PDAC who underwent radical pancreatectomy were included. Associations between clinicopathological and radiological characteristics and specific pattern of progression were investigated. Least absolute shrinkage and selection operator (LASSO) and Cox regression were applied to assess the prognostic factors for overall survival (OS) and progression-free survival (PFS). A total of 302 patients were included into present study, and 173 patients were documented as recurrence after a median survival of 24.7 months. More than half of patients recurred after 12 months after surgery, and the liver was the most common metastatic site. Decreased time interval to progression, elevated carbohydrate antigen 19-9 (CA19-9) level, and lymph node (LN)16 metastasis were independent predictors for reduced OS. Independent prognostic factors for PFS included elevated carcinoembryonic antigen (CEA) level, local progression, liver or lung-only metastasis, local + distant progression, multiple metastases, LN16 metastasis, imaging tumor size, chemotherapy, and tumor–node–metastasis (TNM) stage. The predictive system showed valuable prediction performance with values of concordance indexes (C-indexes) and the area under the receiver operating characteristic curve (AUC) over 0.80. Different survival curves and predictive factors for specific patterns of disease progression suggested the biological heterogeneity, providing new versions into personal management of recurrence in PDAC patients after surgery.

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.

Isolated pulmonary recurrence after resection of pancreatic cancer: the effect of patient factors and treatment modalities on survival

BACKGROUND

The literature suggests favorable survival for patients with isolated pulmonary recurrence after resection of pancreatic ductal adenocarcinoma (PDAC) as compared to other recurrence patterns. Within this cohort, it remains unclear what factors are associated with improved survival.

METHODS

Patients who developed pulmonary recurrence after pancreatectomy were selected from a prospective database. Predictors for post-recurrence survival (PRS) were analyzed using a multivariable Cox regression model.

RESULTS

Ninety-six patients were included. Median recurrence-free survival (RFS), PRS and overall survival (OS) were 16.3, 18.8 and 39.6 months, respectively. Further systemic treatment and/or metastasectomy (n = 64, 67%) was associated with significantly improved PRS and OS when compared to best supportive care (n = 35, 22%) (26.3 vs. 5.3 and 48.1 vs. 18.4, respectively; both P < 0.001). Patients who were able to undergo metastasectomy (n = 19) achieved a PRS and OS of 35.0 and 68.9 months, respectively. More than 5 pulmonary lesions, symptoms and CA 19-9 ≥100 U/mL at time of recurrence were predictive of decreased PRS. A recurrence-free interval of >16 months and treatment for recurrence were independently associated with improved PRS.

CONCLUSIONS

Isolated pulmonary recurrence occurs in 13% of patients with recurrent PDAC and is associated with a median OS of 40 months. Aggressive treatment in highly selected patients was correlated with improved survival.

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.

The effect of postoperative gemcitabine on overall survival in patients with resected pancreatic cancer: A nationwide population-based Danish register study

Background: Adjuvant chemotherapy following curative resection is the standard treatment for pancreatic adenocarcinoma (PC). Randomized clinical trials using gemcitabine have shown a median overall survival (mOS) of 2 years and a 5-year survival rate of 15-20%. However, the effect of gemcitabine outside these trials is less clear. We examined the effect of postoperative gemcitabine on survival in an unselected cohort of patients receiving curative resection for PC in Denmark during a five-year period. Material and methods: From 1 May 2011 to 30 April 2016, 731 patients treated with curative resection were identified in the Danish Pancreatic Cancer Database (DPCD). Thirty patients died within 10 weeks postoperatively; 78 received other regimens or preoperative chemotherapy and were excluded. Of the remaining 623 patients, the chemotherapy (CT) group (n = 409, 66%) received gemcitabine within 10 weeks after resection, whereas the non-chemotherapy (NCT) group (n = 214, 34%) did not receive CT within 10 weeks. Results: CT patients were slightly younger than NCT patients but did not otherwise differ in baseline characteristics. The CT group showed a mOS of 24 months (95% CI; 21-27) and a 5-year survival rate of 22% (95% CI; 17-27); the NCT group had a mOS of 22 months (95% CI; 16-26, p = .27) and a 5-year survival rate of 26% (95% CI; 19-34, p = .66). Most patients (415/623) had lymph node metastases. Of these patients, those in the CT group (n = 280) had significantly longer mOS [20 months (95% CI; 18-24)] than those in the NCT group (n = 135) [14 months (95% CI; 11-17)]. Conclusions: In this national Danish cohort of PC patients undergoing resection between 2011 and 2016, the survival after postoperative gemcitabine was similar to that reported in previous clinical trials. However, the survival advantage of postoperative gemcitabine was limited to patients with lymph node metastases.

Postoperative surveillance of pancreatic cancer patients

BACKGROUND

The aim of this study is to collect the best available evidence for diagnostic modalities, frequency, and duration of surveillance after resection for pancreatic ductal adenocarcinoma (PDAC).

METHODS

PDAC guidelines published after 2015 were collected. Furthermore, a systematic search of the literature on postoperative surveillance was performed in PubMed and Embase from 2000 to 2019. Articles comparing different diagnostic modalities and frequencies of postoperative surveillance in PDAC patients with regard to survival, quality of life, morbidity and cost-effectiveness were selected.

RESULTS

The literature search resulted in 570 articles. A total of seven guidelines and twelve original clinical studies were eventually evaluated. PDAC guidelines increasingly recommend a combination of tumor marker testing and computed tomography (CT) imaging every three to six months during the first two years after resection. These guidelines are, however, based on expert opinion and other low-level evidence. Prospective studies comparing different surveillance strategies are lacking. According to recent studies, surveillance with tumor markers and imaging at regular intervals results in the detection of PDAC recurrence before the onset of symptoms and more frequent administration of further therapy, such as chemotherapy or radiotherapy.

CONCLUSION

Current evidence for recurrence-focused surveillance after PDAC resection is limited and contradictory. Consequently, recommendations on surveillance are conflicting. To define the clinical merit of recurrence-focused surveillance, patients who are most likely to benefit from early detection and treatment of PDAC recurrence need to be identified. To this purpose, well-designed prospective studies are needed, accounting for both economical and psychosocial implications of surveillance.

Age as a prognostic indicator for adjuvant therapy in patients who underwent pancreatic resections for cancer

PURPOSE

In pancreatic cancer, the greatest increase in survival is attained by surgical resection followed by adjuvant chemotherapy. Although surgical complications and functional status are recognized as independent factors for halting adjuvant therapy in patients that undergo pancreatic resections, other elements may play a role in deciding which patients get treated postoperatively. Here we determined demographic and clinical characteristics of patients receiving adjuvant chemotherapy, with the primary intent to investigate if age alone affects rates of adjuvant therapy.

METHODS/MATERIALS

National Cancer Database (NCDB) was queried for patients that underwent surgery for pancreatic cancer. Groups were divided into: adjuvant chemotherapy (n=17,924) and no adjuvant chemotherapy (n=12,947). Basic demographics and treatment characteristics were analyzed. Age was compared with an independent means test; other comparisons used Chi-square test of independence.

RESULTS

There was a statistical difference in age (adjuvant therapy 64.86±9.89 vs. no therapy 67.78±11.22, p<0.001), insurance type, facility type, and cancer stage for patients that received adjuvant therapy and those that did not. Average age of patients not receiving chemotherapy was significantly older at each pathologic stage. Subset analysis of patients treated with chemotherapy showed that the majority of patients received single agent regimens (62%), at an average of 59days following surgery, and at academic cancer programs (52%).

CONCLUSIONS

Regardless of postoperative complications and functional status, age alone appears to affect rates of adjuvant therapy in patients with resected pancreatic cancer. Older patients should be offered tailored regimens that would allow them to complete the intended extent of treatment.

Histone profiling reveals the H1.3 histone variant as a prognostic biomarker for pancreatic ductal adenocarcinoma

Background

Epigenetic alterations have been recognized as important contributors to the pathogenesis of PDAC. However, the role of histone variants in pancreatic tumor progression is still not completely understood. The aim of this study was to explore the expression and prognostic significance of histone protein variants in PDAC patients.

Methods

Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was employed for qualitative analysis of histone variants and histone related post-translational modifications (PTMs) in PDAC and normal pancreatic tissues. Survival analysis was conducted using the Kaplan-Meier method and Cox proportional hazards regression.

Results

Histone variant H1.3 was found to be differentially expressed (p = 0.005) and was selected as a PDAC specific histone variant candidate. The prognostic role of H1.3 was evaluated in an external cohort of patients with resected PDAC using immunohistochemistry. Intratumor expression of H1.3 was found to be an important risk factor for overall survival in PDAC, with an adjusted HR value of 2.6 (95% CI 1.1–6.1), p = 0.029.

Conclusion

We suggest that the intratumor histone H1.3 expression as reported herein, may serve as a new epigenetic biomarker for PDAC.

Protocol of the PANCALYZE trial: a multicenter, prospective study investigating the tumor biomarkers CXCR4, SMAD4, SOX9 and IFIT3 in patients with resected pancreatic adenocarcinoma to predict the pattern of recurrence of the disease

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies today with an urgent need for novel therapeutic strategies. Biomarker analysis helps to better understand tumor biology and might emerge as a tool to develop personalized therapies. The aim of the study is to investigate four promising biomarkers to predict the clinical course and particularly the pattern of tumor recurrence after surgical resection.

DESIGN

Patients undergoing surgery for PDAC can be enrolled into the PANCALYZE trial. Biomarker expression of CXCR4, SMAD4, SOX9 and IFIT3 will be prospectively assessed by immunohistochemistry and verified by rt.-PCR from tumor and adjacent healthy pancreatic tissue of surgical specimen. Immunohistochemistry expression pattern of all four biomarkers will be combined into a single score. Beginning with the hospital stay clinical data from enrolled patients will be collected and followed. Different adjuvant chemotherapy protocols will be used to create subgroups. The combined biomarker expression score will be correlated with the further clinical course of the patients to test the hypothesis if CXCR4 positive, SMAD4 negative, SOX9 positive, IFIT3 positive tumors will predominantly develop metastatic spread.

DISCUSSION

Pancreatic cancer is associated with different patterns of progression requiring personalized therapeutic strategies. Biomarker expression analysis might be a tool to predict the pattern of tumor recurrence and discriminate patients that develop systemic metastatic disease from those with tumors that rather develop local recurrence over time. This data might lead to personalized adjuvant treatment decisions as patients with tumors that stay localized might benefit from adjuvant local therapies like radiochemotherapy as compared to those with systemic recurrence who would benefit exclusively from chemotherapy. Moreover, the pattern of propagation might be a predefined characteristic of pancreatic cancer determined by the genetic signature of the tumor. In the future, biomarker expression analysis could be performed on tumor biopsies to develop personalized therapeutic pathways right after diagnosis of cancer.

TRIAL REGISTRATION

German Clinical Trials Register, DRKS00006179 .

Minimally invasive distal pancreatectomy

BACKGROUND

The first International conference on Minimally Invasive Pancreas Resection was arranged in conjunction with the annual meeting of the International Hepato-Pancreato-Biliary Association (IHPBA), in Sao Paulo, Brazil on April 19th 2016. The presented evidence and outcomes resulting from the session for minimally invasive distal pancreatectomy (MIDP) is summarized and addressed perioperative outcome, the outcome for cancer and patient selection for the procedure.

METHODS

A literature search was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to compare MIDP and open distal pancreatectomy. Patient selection was discussed based on plenary talks, panel discussions and a worldwide survey on MIDP.

RESULTS

Of 582 studies, 52 (40 observational and 12 case-matched) were included in the assessment for outcome for LDP (n = 5023) vs. ODP (n = 16,306) whereas 16 observational comparative studies were identified for cancer outcome. No randomized trials were identified. MIDP resulted in similar outcome to ODP with a tendency for lower blood loss and shorter hospital stay in the MIDP group.

DISCUSSION

Available evidence for comparison of MIDP to ODP is weak, although the number of studies is high. Observed outcomes of MIDP are promising. In the absence of randomized control trials, an international registry should be established.