Recurrence after surgical resection of pancreatic cancer: the importance of postoperative complications beyond tumor biology

MLH1 Inhibits Metastatic Potential of Pancreatic Ductal Adenocarcinoma via Downregulation of GPRC5C

DNA mismatch repair gene MutL homolog-1 (MLH1) has divergent effects in many cancers; however, its impact on the metastasis of pancreatic ductal adenocarcinoma (PDAC) remains unclear. In this study, MLH1 stably overexpressed (OE) and knockdowned (KD) sublines were established. Wound healing and transwell assays were used to evaluate cell migration/invasion. In vivo metastasis was investigated in orthotopic implantation models (severe combined immunodeficiency mice). RT-qPCR and western blotting were adopted to show gene/protein expression. MLH1 downstream genes were screened by transcriptome sequencing. Tissue microarray-based immunohistochemistry was applied to determine protein expression in human specimens. In successfully generated sublines, OE cells presented weaker migration/invasion abilities, compared with controls, whereas in KD cells, these abilities were significantly stronger. The metastasis-inhibitory effect of MLH1 was also observed in mice. Mechanistically, G protein-coupled receptor, family C, group 5, member C (GPRC5C) was a key downstream gene of MLH1 in PDAC cells. Subsequently, transient GPRC5C silencing effectively inhibited cell migration/invasion and remarkably reversed the proinvasive effect of MLH1 knockdown in KD cells. In animal models and human PDAC tissues, tumoral GPRC5C expression, negatively associated with MLH1 expressions, was positively correlated with histologic grade, vessel invasion, and poor cancer-specific survival. In conclusion, MLH1 inhibits the metastatic potential of PDAC via downregulation of GPRC5C.

Associations of body composition parameters with postoperative outcome and perineural tumour invasion after oncological pancreatic resection

BACKGROUND

Pancreatic cancer is often accompanied by wasting conditions. While surgery is the primary curative approach, it poses a substantial risk of postoperative complications, hindering subsequent treatments. Therefore, identifying patients at high risk for complications and optimizing their perioperative general condition is crucial. Sarcopenia and other body composition abnormalities have shown to adversely affect surgical and oncological outcomes in various cancer patients. As most pancreatic tumours are located close to the neuronal control centre for the digestive tract, it is possible that neural infiltration in this area deranges bowel functions and contributes to malabsorption and malnutrition and ultimately worsen sarcopenia and weight loss.

METHODS

A retrospective analysis of CT scans was performed for pancreatic cancer patients who underwent surgical tumour resection at a single high-volume centre from 2007 to 2023. Sarcopenia prevalence was assessed by skeletal muscle index (SMI), and visceral obesity was determined by the visceral adipose tissue area (VAT). Obesity and malnutrition were determined by the GLIM criteria. Sarcopenic obesity was defined as simultaneous sarcopenia and obesity. Postoperative complications, mortality and perineural tumour invasion, were compared among patients with body composition abnormalities.

RESULTS

Of 437 patients studied, 46% were female, the median age was 69 (61;74) years. CT analysis revealed 54.9% of patients with sarcopenia, 23.7% with sarcopenic obesity and 45.9% with visceral obesity. Sarcopenia and sarcopenic obesity were more prevalent in elderly and male patients. Postoperative surgical complications occurred in 67.7% of patients, most of which were mild (41.6%). Severe complications occurred in 22.7% of cases and the mortality rate was 3.4%. Severe postoperative complications were significantly more common in patients with sarcopenia or sarcopenic obesity. Visceral obesity or malnutrition based on BMI alone, did not significantly impact complications. Perineural invasion was found in 80.1% of patients and was unrelated to malnutrition or body composition parameters.

CONCLUSIONS

This is the first and largest study evaluating the associations of CT-based body mass analysis with surgical outcome and histopathological perineural tumour invasion in pancreatic cancer patients. The results suggest that elderly and male patients are at high risk for sarcopenia and should be routinely evaluated by CT before undergoing pancreatic surgery, irrespective of their BMI. Confirmation of the results in prospective studies is needed to assess if pancreatic cancer patients with radiographic sarcopenia benefit from preoperative amelioration of muscle mass and function by exercise and nutritional interventions.

Very Early Recurrence After Curative Resection for Pancreatic Ductal Adenocarcinoma: Proof of Concept for a "Biological R2 Definition"

PURPOSE

Very early recurrence after radical surgery for pancreatic ductal adenocarcinoma (PDAC) has been poorly investigated. This study was designed to evaluate this group of patients who developed recurrence, within 12 weeks after surgery, defined as "biological R2 resections (bR2)."

METHODS

Data from patients who underwent surgical resection as upfront procedure or after neoadjuvant treatment for PDAC between 2015 and 2019 were analyzed. Disease-free, disease-specific survival, and independent predictors of early recurrence were examined. The same analysis was performed separately for upfront and neoadjuvant treated patients.

RESULTS

Of the 573 patients included in the study, 63 (11%) were classified as bR2. The rate of neoadjuvant treatment was similar in bR2 and in the remaining patients (44 vs. 42%, p = 0.78). After a median follow-up of 27 months, median DFS and DSS for the entire cohort were 17 and 43 months, respectively. Median DSS of bR2 group was 13 months. The only preoperative identifiable independent predictor of very early recurrence was body-tail site lesion, whereas all other were pathological: higher pT (8th classification), G3 differentiation, and high lymph node ratio. These predictors were confirmed for patients undergoing upfront surgery, whereas in the neoadjuvant group the only independent predictor was pT.

CONCLUSIONS

One of ten patients with "radical" resected PDAC relapses very early after surgery (bR2); hence, imaging must be routinely repeated within 12 weeks. Despite higher biological aggressiveness and worse pathology, this bR2 cluster eludes our preoperative examinations.

Prognostic Factors for Early Recurrence After Resection of Pancreatic Cancer: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

More than half of pancreatic ductal adenocarcinomas (PDACs) recur within 12 months after curative-intent resection. This systematic review and meta-analysis was conducted to identify all reported prognostic factors for early recurrence in resected PDACs.

METHODS

After a systematic literature search, a meta-analysis was conducted using a random effects model. Separate analyses were performed for adjusted vs unadjusted effect estimates as well as reported odds ratios (ORs) and hazard ratios (HRs). Risk of bias was assessed using the Quality in Prognostic Studies tool, and evidence was rated according to Grading of Recommendations Assessment, Development and Evaluation recommendations.

RESULTS

After 2903 abstracts were screened, 65 studies were included. Of these, 28 studies (43.1%) defined early recurrence as evidence of recurrence within 6 months, whereas 34 (52.3%) defined it as evidence of recurrence within 12 months after surgery. Other definitions were uncommon. Analysis of unadjusted ORs and HRs revealed 41 and 5 prognostic factors for early recurrence within 6 months, respectively. When exclusively considering adjusted data, we identified 25 and 10 prognostic factors based on OR and HR, respectively. Using a 12-month definition, we identified 38 (OR) and 15 (HR) prognostic factors from unadjusted data and 38 (OR) and 30 (HR) prognostic factors from adjusted data, respectively. On the basis of frequency counts of adjusted data, preoperative carbohydrate antigen 19-9, N status, nondelivery of adjuvant therapy, grading, and tumor size based on imaging were identified as key prognostic factors for early recurrence.

CONCLUSIONS

Reported prognostic factors of early recurrence vary considerably. Identified key prognostic factors could aid in the development of a risk stratification framework for early recurrence. However, prospective validation is necessary.

Uncovering the clinicopathological features of early recurrence after surgical resection of pancreatic cancer

To identify risk factors and biomarker for early recurrence in patients diagnosed with pancreatic cancer who undergo curative resection. Early recurrence after curative resection of pancreatic cancer is an obstacle to long-term survival. We retrospectively reviewed 162 patients diagnosed with pancreatic cancer who underwent curative resection. Early recurrence was defined as recurrence within 12 months of surgery. We selected S100A2 as a biomarker and investigated its expression using immunohistochemistry. Of the total, 79.6% (n = 129) of patients received adjuvant chemotherapy after surgery and 117 (72.2%) experienced recurrence, of which 73 (45.1%) experience early recurrence. In multivariate analysis, age < 60 years, presence of lymph node metastasis, and no adjuvant chemotherapy were significantly associated with early recurrence (all P < 0.05). The proportion of patients with high S100A2 expression (H-score > 5) was significantly lower in the early recurrence group (41.5% vs. 63.3%, P = 0.020). The cumulative incidence rate of early recurrence was higher in patients with an S100A2 H-score < 5 (41.5% vs. 63.3%, P = 0.012). The median overall survival of patients with higher S100A2 expression was longer than those with lower S100A2 expression (median 30.1 months vs. 24.2 months, P = 0.003). High-risk factors for early recurrence after surgery for pancreatic cancer include young age, lymph node metastasis, and no adjuvant therapy. Neoadjuvant treatment or intensive adjuvant therapy after surgery may improve the prognosis of patients with high-risk signatures. In patients who receive adjuvant therapy, high S100A2 expression is a good predictor.

Machine Learning of Histopathological Images Predicts Recurrences of Resected Pancreatic Ductal Adenocarcinoma With Adjuvant Treatment

OBJECTIVES

Pancreatic ductal adenocarcinoma is an intractable disease with frequent recurrence after resection and adjuvant therapy. The present study aimed to clarify whether artificial intelligence-assisted analysis of histopathological images can predict recurrence in patients with pancreatic ductal adenocarcinoma who underwent resection and adjuvant chemotherapy with tegafur/5-chloro-2,4-dihydroxypyridine/potassium oxonate.

MATERIALS AND METHODS

Eighty-nine patients were enrolled in the study. Machine-learning algorithms were applied to 10-billion-scale pixel data of whole-slide histopathological images to generate key features using multiple deep autoencoders. Areas under the curve were calculated from receiver operating characteristic curves using a support vector machine with key features alone and by combining with clinical data (age and carbohydrate antigen 19-9 and carcinoembryonic antigen levels) for predicting recurrence. Supervised learning with pathological annotations was conducted to determine the significant features for predicting recurrence.

RESULTS

Areas under the curves obtained were 0.73 (95% confidence interval, 0.59-0.87) by the histopathological data analysis and 0.84 (95% confidence interval, 0.73-0.94) by the combinatorial analysis of histopathological data and clinical data. Supervised learning model demonstrated that poor tumor differentiation was significantly associated with recurrence.

CONCLUSIONS

Results indicate that machine learning with the integration of artificial intelligence-driven evaluation of histopathological images and conventional clinical data provides relevant prognostic information for patients with pancreatic ductal adenocarcinoma.

Serious complications of pancreatoduodenectomy correlate with lower rates of adjuvant chemotherapy: Results from the recurrence after Whipple's (RAW) study

INTRODUCTION

Adjuvant chemotherapy (AC) can prolong overall survival (OS) after pancreatoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC). However, fitness for AC may be influenced by postoperative recovery. We aimed to investigate if serious (Clavien-Dindo grade ≥ IIIa) postoperative complications affected AC rates, disease recurrence and OS.

MATERIALS AND METHODS

Data were extracted from the Recurrence After Whipple's (RAW) study (n = 1484), a retrospective study of PD outcomes (29 centres from eight countries). Patients who died within 90-days of PD were excluded. The Kaplan-Meier method was used to compare OS in those receiving or not receiving AC, and those with and without serious postoperative complications. The groups were then compared using univariable and multivariable tests.

RESULTS

Patients who commenced AC (vs no AC) had improved OS (median difference: (MD): 201 days), as did those who completed their planned course of AC (MD: 291 days, p < 0.0001). Those who commenced AC were younger (mean difference: 2.7 years, p = 0.0002), more often (preoperative) American Society of Anesthesiologists (ASA) grade I-II (74% vs 63%, p = 0.004) and had less often experienced a serious postoperative complication (10% vs 18%, p = 0.002). Patients who developed a serious postoperative complication were less often ASA grade I-II (52% vs 73%, p = 0.0004) and less often commenced AC (58% vs 74%, p = 0.002).

CONCLUSION

In our multicentre study of PD outcomes, PDAC patients who received AC had improved OS, and those who experienced a serious postoperative complication commenced AC less frequently. Selected high-risk patients may benefit from targeted preoperative optimisation and/or neoadjuvant chemotherapy.

R1 pancreatic cancer patients benefit from chemoradiation when initiation of adjuvant therapy is delayed

BACKGROUND

Adjuvant chemotherapy (AC) following pancreaticoduodenectomy (PD) for pancreas cancer (PDAC) has been demonstrated to improve survival. However, the optimal adjuvant treatment (AT) regimen for R1-margin patients remains unclear. This retrospective study investigates the impact of AC vs. adjuvant chemoradiotherapy (ACRT) on survival (OS).

MATERIAL AND METHODS

The NCDB was queried for patients with PDAC who underwent PD between 2010 and 2018. Patients were divided into, (A) AC<60 days, (B) ACRT<60 days, (C) AC≥60 days, and (D) ACRT≥60 days. Kaplan-Meier survival analyses and Cox multivariable regression analyses were performed.

RESULTS

Among 13 740 patients, median OS was 23.7 months. For R1 patients, median OS for timely AC and ACRT, and delayed AC and ACRT was 19.91, 19.19, 15.24, 18.96 months, respectively. While time of AC initiation was an insignificant factor for R0 patients (p = 0.263, CI 0.957-1.173), a survival benefit was found for R1 patients who received AC<60 vs. ≥60 days (p = 0.041, CI 1.002-1.42). Among R1 patients, administration of delayed ACRT achieves the same survival benefit of timely AC initiation (p = 0.074, CI 0.703-1.077).

CONCLUSION

The study suggests value in ACRT for patients with R1 margins when delay of AT≥60 days cannot be avoided. Hence, ACRT may mitigate the negative impact of delayed AT initiation for R1-patients.

Five-year follow-up after pancreatoduodenectomy performed for malignancy: A single-centre study

Backgrounds/Aims

The aim of this study was to describe short- and long-term outcomes of patients who underwent pancreatoduodenectomy (PD) at a typical United Kingdom hepatopancreatobiliary unit.

Methods

A retrospective analysis of all PD patients with histologically-confirmed pancreatic ductal adenocarcinoma (PDAC), ampullary adenocarcinoma (AA), or distal cholangiocarcinoma (CC) from September 1st, 2006 to May 31st, 2015 was carried out. The following information was obtained: demographics, comorbidities, preoperative investigations, neoadjuvant treatment, operative details, postoperative management, complications, adjuvant treatment, five-year recurrence, and five-year survival. Effects of selected preoperative variables on short- and long-term outcomes were investigated.

Results

Of 271 included patients, 57.9% had PDAC, 25.8% had AA, and 16.2% had CC. In total, 67.9% experienced morbidity and 17.3% developed a Clavien-Dindo grade ≥ III complication. The 90-day mortality was 3.3%. Clinically-relevant postoperative pancreatic fistula, bile leak, gastrojejunal leak, postpancreatectomy haemorrhage and delayed gastric emptying affected 8.1%, 4.1%, 0.0%, 9.2%, and 19.9% of patients, respectively. American Society of Anesthesiologists grade III-VI correlated with overall morbidity (p = 0.002) and major morbidity (p = 0.009), but not 90-day mortality or five-year survival. The same pattern was observed in patients with a preoperative serum bilirubin > 29 μmol/L and/or a neutrophil/lymphocyte ratio > 3.1. Five-year cancer recurrence and five-year survival were 68.3% and 22.5%, respectively. PDAC patients had higher five-year recurrence but lower five-year survival rates (both p = 0.001).

Conclusions

In our series, the majority of patients experienced a complication. However, few patients experienced major morbidity. Surgical risk factors did not affect five-year survival.

Mesenchymal Stromal Cell-Based Targeted Therapy Pancreatic Cancer: Progress and Challenges

Pancreatic cancer is an aggressive malignancy with high mortality rates and poor prognoses. Despite rapid progress in the diagnosis and treatment of pancreatic cancer, the efficacy of current therapeutic strategies remains limited. Hence, better alternative therapeutic options for treating pancreatic cancer need to be urgently explored. Mesenchymal stromal cells (MSCs) have recently received much attention as a potential therapy for pancreatic cancer owing to their tumor-homing properties. However, the specific antitumor effect of MSCs is still controversial. To this end, we aimed to focus on the potential anti-cancer treatment prospects of the MSC-based approach and summarize current challenges in the clinical application of MSCs to treat pancreatic cancer.

Serious complications of pancreatoduodenectomy correlate with lower rates of adjuvant chemotherapy: Would high-risk patients benefit from neoadjuvant therapy?

INTRODUCTION

Patients who suffer a serious complication of pancreatoduodenectomy (PD) may have their adjuvant chemotherapy (AC) delayed or omitted as a result. We aimed to investigate whether PD complications affected AC rates.

MATERIALS AND METHODS

A retrospective analysis of all PD patients with histologically-confirmed pancreatic ductal adenocarcinoma (2006-2015) was performed; 90-day mortality patients were excluded. Patients who commenced AC were compared to those who did not (morbidity rates and survival) and patients who developed selected postoperative complications were compared to those who did not (AC rates and survival).

RESULTS

157 patients were included and 90-day mortality was 3.8%. Of the remaining patients, 102 (68.5%) received AC (AC data unavailable for two patients). Survival was longer in the AC group (p = 0.004). AC patients had less frequently experienced a postoperative chest infection (8.82% vs 34.0%, p = 0.0003) or a postoperative complication which was Clavien-Dindo (CD) grade ≥ II (29.4% vs 57.4%, p = 0.0019) or ≥ III (6.86% vs 21.3%, p = 0.023). Patients who experienced a postoperative chest infection (36.0% vs 75.0%, p = 0.0003) or a postoperative complication which was CD grade ≥ II (48.9% vs 73.1%, p = 0.0099) or ≥ III (29.4% vs 70.3%, p = 0.0018) less frequently commenced AC.

CONCLUSION

Patients who received AC had less frequently experienced a serious postoperative complication. Efforts should be made to preoperatively identify those who are high-risk for a serious complication as this cohort may benefit from neoadjuvant therapy.

Indications to total pancreatectomy for positive neck margin after partial pancreatectomy: a review of a slippery ground

The extension of a partial pancreatectomy up to total pancreatectomy because of positive neck margin examined at intraoperative frozen section (IFS) analysis is an accepted procedure in modern pancreatic surgery with good accuracy. The goal of this practice is to improve the rate of radical (R0) resection in malignant tumors, mainly pancreatic ductal adenocarcinoma (PDAC), and to completely resect pre-invasive neoplasms such as intraductal papillary mucinous neoplasms (IPMNs). In the setting of IPMNs there is a consensus for pancreatic re-resection when high-grade dysplasia and invasive cancer are present at the neck margin. The presence of denudation is another indication for further resection in IPMNs. The role of IFS analysis in the management of pancreatic cancer is more debated. The presence of a positive intraoperative transection margin can be considered the surrogate of a biologically aggressive disease associated with a poorer prognosis. There are conflicting data regarding possible advantages of pancreatic re-resection up to total pancreatectomy, and the lack of randomized trials comparing different strategies does not offer a definitive answer. The goal of this review is to provide an up-to-date overview of the role IFS analysis of pancreatic margin and of pancreatic re-resection up to total pancreatectomy considering different pancreatic tumors.

Predicting Survival in Patients with Pancreatic Cancer by Integrating Bone Marrow FDG Uptake and Radiomic Features of Primary Tumor in PET/CT

Simple Summary

FDG uptake of bone marrow (BM) is known to reflect the degree of host inflammatory response to cancer cells and showed significant association with survival in diverse kinds of cancers. The aim of this retrospective study was to evaluate the prognostic significance of FDG uptake of BM and to investigate whether integrating FDG uptake of BM and radiomic features of primary tumors could improve the prediction of overall survival (OS) in patients with pancreatic cancer. In multivariable survival analysis, along with total lesion glycolysis (TLG) and first-order entropy of primary tumor lesions, FDG uptake of BM was an independent predictor of OS. We designed a PET/CT scoring system based on the cumulative scores of tumor factors (TLG and first-order entropy) and host factors (FDG uptake of BM). This scoring system was able to stratify the patients with three distinct prognostic groups independent of clinical stage and treatment modality.

Abstract

The purpose of this study was to evaluate the prognostic significance of FDG uptake of bone marrow (BM SUV) and to investigate its role combined with radiomic features of primary tumors in improving the prediction of overall survival (OS) in patients with pancreatic cancer. We retrospectively enrolled 65 pancreatic cancer patients with staging FDG PET/CT. BM SUV and conventional imaging parameters of primary tumors including total lesion glycolysis (TLG) were measured. First-order and higher-order textural features of primary cancer were extracted using PET textural analysis. Associations of PET/CT parameters of bone marrow (BM) and primary cancer with OS were assessed. BM SUV as well as TLG and first-order entropy of pancreatic cancer were significant independent predictors of OS in multivariable analysis. A PET/CT scoring system based on the cumulative scores of these three independent predictors enabled patient stratification into three distinct prognostic groups. The scoring system yielded a good prognostic stratification based on subgroup analysis irrespective of tumor stage and treatment modality. BM SUV was an independent predictor of OS in pancreatic cancer patients. The PET/CT scoring system that integrated PET/CT parameters of primary tumors and BM can provide prognostic information in pancreatic cancer independent of tumor stage and treatment.