Impact on Long-term Survival of a Standardized Histopathological Protocol on the R1 Incidence in Pancreatoduodenectomy for Pancreatic Ductal Adenocarcinoma.

Background: Pancreatic Ductal Adenocarcinoma (PDAC) is a pathology with a very poor prognostic, the only curative treatment option being surgery, in association with chemotherapy. This study aims to assess the influence that the use of a standardized pathology report after a pancreaticoduodenectomy (PD) has on the R1 margins rate and the impact that this has on long term survival. Material and Methods: We included 116 patients admitted to the Regional Institute of Gastroenterology and Hepatology Prof. Dr. O. Fodor Cluj Napoca, who underwent PD for PDAC (Pancreatic Ductal Adenocarcinoma) between January 2012 and May 2017. We divided them in two groups: 59 patients for which a nonstandardized histopathological protocol was used and 57 patients for which a standardized protocol was implemented. We considered a margin to be R1 when there were tumor cells at ¤ 1 mm from the resection margin. Results: The R1 percentage in the first group of patients was of 39%, while the R1 resection rate in the second group was of 68.4%. The median survival rate was similar in the two groups, with no statistically significant difference between them, but in the prospective study when comparing R0 vs R1 margins there was a statistically differences in 5 year OS with a p-value = 0.03. Conclusion: The use of a standardized pathology report reveals a significant increase in R1 resection rates. Also study revealed not only increasing R1 incidence when using a standardized histopathology report, but also that those margins (R1) playing a determinant role in 5-year OS. The mesopancreas is the most frequently R1 resection margin.

Prognostic significance of preoperative lymphocytes, albumin, and neutrophils (LANR) index in resectable pancreatic ductal adenocarcinoma.

PURPOSE: The index composed of preoperative lymphocytes, albumin, and neutrophils (LANR), a new composite score based on inflammatory response and nutritional status, has been reported to be associated with the prognosis of multiple types of cancer, but the role of LANR in the prognosis of resectable pancreatic ductal adenocarcinoma (PDAC) has not yet been elucidated. PATIENTS AND METHODS: The data of 142 patients with PDAC who underwent radical resection in the Affiliated Hospital of Jiangnan University from January 2015 to December 2018 were retrospectively analyzed. Receiver Operating Characteristic (ROC) curves were generated to determine the optimal cut-off values for these parameters, as well as the sensitivity and specificity of LANR in predicting survival. The Kaplan-Meier method was used to draw the survival curves. Log rank test was used for univariate analysis, and Cox proportional hazards regression model was used for multivariate analysis.  RESULTS: The optimal cut-off value of LANR was 18.145, and a low preoperative LANR was significantly correlated with the location of the tumor (p = 0.047). Multivariate analysis showed that tumor differentiation degree (HR:2.357, 95%CI:1.388-4.003,p = 0.002), lymph node metastasis (HR:1.755, 95%CI: 1.115-2.763, p = 0.015), TNM stage (HR:4.686, 95%CI: 2.958-7.425, p < 0.001), preoperative cancer antigen 19 - 9 levels (HR:1.001, 95%CI: 1.000-1.001, p < 0.001) and preoperative LANR (HR:0.221, 95%CI: 0.111-0.441, p < 0.001) were independent risk factors for a poor prognosis in patients undergoing radical resection of PDAC. CONCLUSION: This study found that preoperative LANR can be used to assess the prognosis of radical resection in patients with PDAC; those with low preoperative LANR had a worse outcome.

Smoking history is associated with reduced efficacy of neoadjuvant therapy in pancreatic adenocarcinoma.

BACKGROUND: Differential responses to neoadjuvant therapy (NAT) exist in pancreatic ductal adenocarcinoma (PDAC); however, contributing factors are poorly understood. Tobacco smoke is a common risk factor for PDAC, with nicotine-induced chemoresistance observed in other cancers. This study aimed to explore the potential association between tobacco use and NAT efficacy in PDAC. METHODS: A single-center, retrospective analysis was conducted that included all consecutive patients with PDAC who underwent surgical resection after NAT with a documented smoking history (N = 208). NAT response was measured as percentage fibrosis in the surgical specimen. Multivariable models controlled for covariates and survival were modeled using the Kaplan-Meier method. RESULTS: Postoperatively, major responses to NAT (>95% fibrosis) were less frequently observed in smokers than in nonsmokers (13.7% vs 30.4%, respectively; P = .021). Pathologic complete responses were similarly less frequent in smokers than in nonsmokers (2.1% vs 9.9%, respectively; P = .023). On multivariate analysis controlling for covariates, smoking history remained independently associated with lower odds of major fibrosis (odds ratio [OR], 0.25; 95% CI, 0.10-0.59; P = .002) and pathologic complete response (OR, 0.21; 95% CI, 0.03-0.84; P = .05). The median overall survival was significantly longer in nonsmokers than in smokers (39.1 vs 26.6 months, respectively; P = .05). CONCLUSION: Tobacco use was associated with diminished pathologic responses to NAT. Future research to understand the biology underlying this observation is warranted and may inform differential NAT approaches or counseling among these populations.

Common hepatic artery lymph node metastasis in pancreatic ductal adenocarcinoma: an analysis of actual survival.

BACKGROUND: The common hepatic artery lymph node (CHALN) represents a second-echelon node for tumors in the head of the pancreas. Although early studies suggested survival was comparable between the CHALN and remote metastasis in pancreatic ductal adenocarcinoma (PDAC), whether the lymph node is associated with adverse survival remains equivocal. Here, we examined a prospective cohort of patients calculating actual survival to better understand implications of this specific lymph node metastasis. METHODS: We studied 215 patients with pancreatic head PDAC, who underwent pancreaticoduodenectomies at a single institution between 2010 and 2017, wherein the CHALNs were excised. We performed actual and actuarial overall survival and disease-free survival (DFS) analyses, with subsequent univariate and multivariate analyses in node-positive patients. RESULTS: Of this cohort, 7.3% of patients had involvement of the CHALN, and all of them had metastatic spread to first-echelon nodes. Actual median survival of patients with no lymph node involvement was 49 months. In patients with any nodal involvement, the survival was no different when comparing the lymph node positive and negative (13 and 20 months, respectively). Univariate and multivariate analyses likewise attached no significance to the lymph node metastasis, while demonstrating worse survival with positive margin status and poorly differentiated histology. Our DFS analyses yielded similar results. CONCLUSION: We found no difference in actual survival in node-positive patients regardless of the CHALN involvement and recommended against its assessment in prognosticating survival or guiding surgical treatment.

Adjuvant chemotherapy for adenocarcinoma arising from intraductal papillary mucinous neoplasia: multicentre ADENO-IPMN study.

BACKGROUND: The clinical impact of adjuvant chemotherapy after resection for adenocarcinoma arising from intraductal papillary mucinous neoplasia is unclear. The aim of this study was to identify factors related to receipt of adjuvant chemotherapy and its impact on recurrence and survival. METHODS: This was a multicentre retrospective study of patients undergoing pancreatic resection for adenocarcinoma arising from intraductal papillary mucinous neoplasia between January 2010 and December 2020 at 18 centres. Recurrence and survival outcomes for patients who did and did not receive adjuvant chemotherapy were compared using propensity score matching. RESULTS: Of 459 patients who underwent pancreatic resection, 275 (59.9%) received adjuvant chemotherapy (gemcitabine 51.3%, gemcitabine-capecitabine 21.8%, FOLFIRINOX 8.0%, other 18.9%). Median follow-up was 78 months. The overall recurrence rate was 45.5% and the median time to recurrence was 33 months. In univariable analysis in the matched cohort, adjuvant chemotherapy was not associated with reduced overall (P = 0.713), locoregional (P = 0.283) or systemic (P = 0.592) recurrence, disease-free survival (P = 0.284) or overall survival (P = 0.455). Adjuvant chemotherapy was not associated with reduced site-specific recurrence. In multivariable analysis, there was no association between adjuvant chemotherapy and overall recurrence (HR 0.89, 95% c.i. 0.57 to 1.40), disease-free survival (HR 0.86, 0.59 to 1.30) or overall survival (HR 0.77, 0.50 to 1.20). Adjuvant chemotherapy was not associated with reduced recurrence in any high-risk subgroup (for example, lymph node-positive, higher AJCC stage, poor differentiation). No particular chemotherapy regimen resulted in superior outcomes. CONCLUSION: Chemotherapy following resection of adenocarcinoma arising from intraductal papillary mucinous neoplasia does not appear to influence recurrence rates, recurrence patterns or survival.

A 15-Inflammation-Related Gene Signature Predicts the Prognosis of Patients With Pancreatic Ductal Adenocarcinoma.

Chronic inflammation promotes the development of pancreatic ductal adenocarcinoma (PDAC) and PDAC-related inflammatory tumor microenvironment facilitates tumor growth and metastasis. Thus, we aimed to study the association between inflammatory response and prognosis in patients with PDAC. We conducted the whole transcriptomic sequencing using tissue samples collected from patients diagnosed with PDAC (n = 106) recruited from Shandong Cancer Hospital. We first constructed a prognostic signature using 15 inflammation-related genes in The Cancer Genome Atlas (TCGA) cohort (n = 177) and further validated it in an independent International Cancer Genome Consortium (ICGC) cohort (n = 90) and our in-house cohort. PDAC patients with a higher risk score had poorer overall survival (OS) (P < 0.001; HR, 3.02; 95% CI, 1.94-4.70). The association between the prognostic signature and OS remained significant in the multivariable Cox regression adjusting for age, sex, alcohol exposure, diabetes, and stage (P < 0.001; HR, 2.91; 95% CI, 1.73-4.89). This gene signature also robustly predicted prognosis in the ICGC cohort (P = 0.01; HR, 1.94; 95% CI, 1.14-3.30) and our cohort (P < 0.001; HR, 2.40; 95% CI, 1.45-3.97). Immune subtype C3 (inflammatory) was enriched and CD8+ T cells were higher in patients with a lower risk score (P < 0.05). Furthermore, PDAC patients with higher risk scores were more sensitive to chemotherapy, immunotherapy, and PARP inhibitors (P < 0.05). In sum, we identified a novel gene signature that was associated with inflammatory response for risk stratification, prognosis prediction, and therapy guidance in PDAC patients. Future studies are warranted to validate the clinical utility of the signature.

Impact of Surgery-Induced Myeloid-derived Suppressor Cells and the NOX2/ROS Axis on Postoperative Survival in Human Pancreatic Cancer.

Preclinical studies imply that surgery triggers inflammation that may entail tumor outgrowth and metastasis. The potential impact of surgery-induced inflammation in human pancreatic cancer is insufficiently explored. This study included 17 patients with periampullary cancer [pancreatic ductal adenocarcinoma (PDAC) n = 14, ampullary carcinoma n = 2, cholangiocarcinoma n = 1] undergoing major pancreatic cancer surgery with curative intent. We analyzed the potential impact of preoperative and postoperative immune phenotypes and function on postoperative survival with >30 months follow-up. The surgery entailed prompt expansion of monocytic myeloid-derived suppressor cells (M-MDSC) that generated NOX2-derived reactive oxygen species (ROS). Strong induction of immunosuppressive M-MDSC after surgery predicted poor postoperative survival and coincided with reduced functionality of circulating natural killer (NK) cells. The negative impact of surgery-induced M-MDSC on survival remained significant in separate analysis of patients with PDAC. M-MDSC-like cells isolated from patients after surgery significantly suppressed NK cell function ex vivo, which was reversed by inhibition of NOX2-derived ROS. High NOX2 subunit expression within resected tumors from patients with PDAC correlated with poor survival whereas high expression of markers of cytotoxic cells associated with longer survival. The surgery-induced myeloid inflammation was recapitulated in vivo in a murine model of NK cell-dependent metastasis. Surgical stress thus induced systemic accumulation of M-MDSC-like cells and promoted metastasis of NK cell-sensitive tumor cells. Genetic or pharmacologic suppression of NOX2 reduced surgery-induced inflammation and distant metastasis in this model. We propose that NOX2-derived ROS generated by surgery-induced M-MDSC may be targeted for improved outcome after pancreatic cancer surgery. SIGNIFICANCE: Pancreatic cancer surgery triggered pronounced accumulation of NOX2+ myeloid-derived suppressor cells that inhibited NK cell function and negatively prognosticated postoperative patient survival. We propose the targeting of M-MDSC as a conceivable strategy to reduce postoperative immunosuppression in pancreatic cancer.

Expression landscape of cancer-FOXP3 and its prognostic value in pancreatic adenocarcinoma.

FOXP3, a key identifier of Treg, has also been identified in tumor cells, which is referred to as cancer-FOXP3 (c-FOXP3). Human c-FOXP3 undergoes multiple alternative splicing events, generating several isoforms, like c-FOXP3FL and c-FOXP3Δ3. Previous research on c-FOXP3 often ignore its cellular source (immune or tumor cells) and isoform expression patterns, which may obscure our understanding of its clinical significance. Our immunohistochemistry investigations which conducted across 18 tumors using validated c-FOXP3 antibodies revealed distinct expression landscapes for c-FOXP3 and its variants, with the majority of tumors exhibited a predominantly expression of c-FOXP3Δ3. In pancreatic ductal adenocarcinoma (PDAC), we further discovered a potential link between nuclear c-FOXP3Δ3 in tumor cells and poor prognosis. Overexpression of c-FOXP3Δ3 in tumor cells was associated with metastasis. This work elucidates the expression pattern of c-FOXP3 in pan-cancer and indicates its potential as a prognostic biomarker in clinical settings, offering new perspectives for its clinical application.

A Predictive Noninvasive Single-Nucleotide Variation-Based Biomarker Signature for Resectable Pancreatic Cancer: Protocol for a Prospective Validation Study.

BACKGROUND: Single-nucleotide variations (SNVs; formerly SNPs) are inherited genetic variants that can be easily determined in routine clinical practice using a simple blood or saliva test. SNVs have potential to serve as noninvasive biomarkers for predicting cancer-specific patient outcomes after resection of pancreatic ductal adenocarcinoma (PDAC). Two recent analyses led to the identification and validation of three SNVs in the CD44 and CHI3L2 genes (rs187115, rs353630, and rs684559), which can be used as predictive biomarkers to help select patients most likely to benefit from pancreatic resection. These variants were associated with an over 2-fold increased risk for tumor-related death in three independent PDAC study cohorts from Europe and the United States, including The Cancer Genome Atlas cohorts (reaching a P value of 1×10-8). However, these analyses were limited by the inherent biases of a retrospective study design, such as selection and publication biases, thereby limiting the clinical use of these promising biomarkers in guiding PDAC therapy. OBJECTIVE: To overcome the limitations of previous retrospectively designed studies and translate the findings into clinical practice, we aim to validate the association of the identified SNVs with survival in a controlled setting using a prospective cohort of patients with PDAC following pancreatic resection. METHODS: All patients with PDAC who will undergo pancreatic resection at three participating hospitals in Switzerland and fulfill the inclusion criteria will be included in the study consecutively. The SNV genotypes will be determined using standard genotyping techniques from patient blood samples. For each genotyped locus, log-rank and Cox multivariate regression tests will be performed, accounting for the relevant covariates American Joint Committee on Cancer stage and resection status. Clinical follow-up data will be collected for at least 3 years. Sample size calculation resulted in a required sample of 150 patients to sufficiently power the analysis. RESULTS: The follow-up data collection started in August 2019 and the estimated end of data collection will be in May 2027. The study is still recruiting participants and 142 patients have been recruited as of November 2023. The DNA extraction and genotyping of the SNVs will be performed after inclusion of the last patient. Since no SNV genotypes have been determined, no data analysis has been performed to date. The results are expected to be published in 2027. CONCLUSIONS: This is the first prospective study of the CD44 and CHI3L2 SNV-based biomarker signature in PDAC. A prospective validation of this signature would enable its clinical use as a noninvasive predictive biomarker of survival after pancreatic resection that is readily available at the time of diagnosis and can assist in guiding PDAC therapy. The results of this study may help to individualize treatment decisions and potentially improve patient outcomes. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/54042.

Handgrip Strength Predicts Survival in Patients With Pancreatic Cancer.

OBJECTIVES: Pancreatic ductal adenocarcinoma (PDAC) is a common cancer with a poor prognosis and is associated with a high prevalence of cachexia, a metabolic syndrome of muscle wasting due to complex mechanisms. In addition to loss of muscle mass, cancer patients also experience functional deterioration. The aim of this study is to determine whether there is an association between muscle mass and function and clinical outcomes, particularly survival. METHODS: We performed a prospective cohort study including all patients with PDAC at Monash Health from March 2016 to December 2017. We conducted body composition analysis for myopenia and handgrip strength testing. We constructed Kaplan-Meier curves to estimate whether myopenia and low hand grip strength were associated with poorer survival. RESULTS: Myopenia was not associated with a significant difference in PDAC-specific survival (log-rank P = 0.60). However, low handgrip strength was associated with significantly worse PDAC-specific survival compared with other patients (log-rank hazard ratio, 1.88; 95% confidence interval, 1.15-3.09; P = 0.004). CONCLUSIONS: The relationship between survival in PDAC and handgrip strength, but not anatomical muscle mass, suggests that functional testing of strength may be important in prognostication of patients with PDAC, alongside existing tools such as the Eastern Cooperative Oncology Group performance status.

Gastrointestinal cancer precursor risk and mortality in pancreatic intraductal papillary mucinous neoplasms: a nationwide cohort study.

BACKGROUND AND AIMS: Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a precursor of pancreatic cancer. While earlier research has shown a high prevalence of synchronous/metachronous extrapancreatic tumors in IPMN patients, these studies have often been small with retrospective data collection. The aim of the study was to examine absolute and relative risks of non-pancreatic gastrointestinal (GI) cancer precursors and mortality in histologically confirmed IPMN. METHODS: Through the nationwide ESPRESSO histopathology cohort, we retrieved data on IPMN between 1965 and 2016. Each index case was matched to ≤5 general population controls. Through Cox regression, we estimated hazard ratios (HRs) for future GI cancer precursors and death. RESULTS: A total of 117 patients with IPMN and 539 age- and sex-matched controls were included. Over a median of 2.1 years of follow up, we confirmed two (1.7%) incident GI cancer precursors in IPMN vs. four (0.7%) in controls, corresponding to an HR of 1.89 (95%CI = 0.34-10.55). By contrast, IPMN patients were at increased risk of death (HR 3.61 (95%CI = 1.79-7.27)). The most common cause of death in IPMN was pancreatic cancer (n = 14; 45.2% of all deaths). CONCLUSIONS: We found no association between IPMN and other GI cancer precursors. This argues against comprehensive routine surveillance for other GI cancer precursors in IPMN patients. Mortality was increased in IPMN with pancreatic cancer being the most common cause of death, indicating the need for lifelong follow up in all resected and non-resected patients with IPMN. However, results should be confirmed in larger cohorts.

Postoperative infectious complications worsen oncologic outcomes following pancreaticoduodenectomy for pancreatic ductal adenocarcinoma.

BACKGROUND: Pancreaticoduodenectomy (PD) remains the only curative option for patients with pancreatic adenocarcinoma (PDAC). Infectious complications (IC) can negatively impact patient outcomes and delay adjuvant therapy in most patients. This study aims to determine IC effect on overall survival (OS) following PD for PDAC. STUDY DESIGN: Patients who underwent PD for PDAC between 2010 and 2020 were identified from a single institutional database. Patients were categorized into two groups based on whether they experienced IC or not. The relationship between postoperative IC and OS was investigated using Kaplan-Meier and Cox-regression multivariate analysis. RESULTS: Among 655 patients who underwent PD for PDAC, 197 (30%) experienced a postoperative IC. Superficial wound infection was the most common type of infectious complication (n = 125, 63.4%). Patients with IC had significantly more minor complications (Clavien-Dindo [CD] < 3; [59.4% vs. 40.2%, p < 0.001]), major complications (CD ≥ 3; [37.6% vs. 18.8%, p < 0.001]), prolonged LOS (47.2% vs 20.3%, p < 0.001), biochemical leak (6.1% vs. 2.8%, p = 0.046), postoperative bleeding (4.1% vs. 1.3%, p = 0.026) and reoperation (9.6% vs. 2.2%, p < 0.001). Time to adjuvant chemotherapy was delayed in patients with IC versus those without (10 vs. 8 weeks, p < 0.001). Median OS for patients who experienced no complication, noninfectious complication, and infectious complication was 33.3 months, 29.06 months, and 27.58 months respectively (p = 0.023). On multivariate analysis, postoperative IC were an independent predictor of worse OS (HR 1.32, p = 0.049). CONCLUSIONS: IC following PD for PDAC independently predict worse oncologic outcomes. Thus, efforts to prevent and manage IC should be a priority in the care of patients undergoing PD for PDAC.

Evidence for molecular subtyping in pancreatic ductal adenocarcinoma: a systematic review.

BACKGROUND: Pancreatic Ductal Adenocarcinoma (PDAC) patients exhibit varied responses to multimodal therapy. RNA gene sequencing has unravelled distinct tumour biology subtypes, forming the focus of this review exploring its impact on survival outcomes. METHODS: A systematic search across PubMed, Medline, Embase, and CINAHL databases targeted studies assessing long-term overall and disease-free survival in PDAC patients with molecular subtyping. RESULTS: Fifteen studies including 2731 patients were identified. Molecular subtyping was performed by RNA sequencing and Immunohistochemistry in 14 studies and by Mass Spectrometry in 1 study. Two main tumour subtypes were identified (classical and basal-like or squamous) with basal like associated with poorer outcomes. Further subtypes were identified in individual studies. Superior survival was seen with classical subtype in all other analyses that compared the classical and basal subtypes. High risk stromal subtypes were identified on further analysis of the stroma and were associated with a worse survival independent of the tumour subtype. CONCLUSION: Molecular subtyping of PDAC specimens can identify patients with high-risk tumour biology and poor survival outcomes. Routine subtyping is limited by the cost of RNA sequencing and the volume of raw data generated which has made its translation into routine clinical practice difficult.

Acid sphingomyelinase expression is associated with survival in resectable pancreatic ductal adenocarcinoma.

Pancreatic adenocarcinoma (PDAC) is one of the most common cancers worldwide. Unfortunately, the prognosis of PDAC is rather poor, and for instance, in the USA, over 47,000 people die because of pancreatic cancer annually. Here, we demonstrate that high expression of acid sphingomyelinase in PDAC strongly correlates with long-term survival of patients, as revealed by the analysis of two independent data sources. The positive effects of acid sphingomyelinase expression on long-term survival of PDAC patients were independent of patient demographics as well as tumor grade, lymph node involvement, perineural invasion, tumor stage, lymphovascular invasion, and adjuvant therapy. We also demonstrate that genetic deficiency or pharmacological inhibition of the acid sphingomyelinase promotes tumor growth in an orthotopic mouse model of PDAC. This is mirrored by a poorer pathologic response, as defined by the College of American Pathologists (CAP) score for pancreatic cancer, to neoadjuvant therapy of patients co-treated with functional inhibitors of the acid sphingomyelinase, in particular tricyclic antidepressants and selective serotonin reuptake inhibitors, in a retrospective analysis. Our data indicate expression of the acid sphingomyelinase in PDAC as a prognostic marker for tumor progression. They further suggest that the use of functional inhibitors of the acid sphingomyelinase, at least of tricyclic antidepressants and selective serotonin reuptake inhibitors in patients with PDAC, is contra-indicated. Finally, our data also suggest a potential novel treatment of PDAC patients with recombinant acid sphingomyelinase. KEY MESSAGES: Pancreatic ductal adenocarcinoma (PDAC) is a common tumor with poor prognosis. Expression of acid sphingomyelinase (ASM) determines outcome of PDAC. Genetic deficiency or pharmacologic inhibition of ASM promotes tumor growth in a mouse model. Inhibition of ASM during neoadjuvant treatment for PDAC correlates with worse pathology. ASM expression is a prognostic marker and potential target in PDAC.

Association of Adjuvant Chemotherapy in Patients With Resected Pancreatic Adenocarcinoma After Multiagent Neoadjuvant Chemotherapy.

Importance: The total number of patients with pancreatic ductal adenocarcinoma (PDAC) who receive neoadjuvant chemotherapy (NAC) is increasing. However, the added role of adjuvant chemotherapy (AC) in these patients remains unknown. Objective: To evaluate the association of AC with overall survival (OS) in patients with PDAC who received multiagent NAC followed by curative-intent surgery. Design, Setting, and Participants: This retrospective, matched-cohort study used data from the National Cancer Database and included patients with PDAC diagnosed between 2010 and 2018. The study included patients at least 18 years of age who received multiagent NAC followed by surgical resection and had available records of the pathological findings. Patients were excluded if they had clinical or pathological stage IV disease or died within 90 days of their operation. Exposures: All included patients received NAC and underwent resection for primary PDAC. Some patients received adjuvant chemotherapy. Main Outcomes and Measures: The main outcome was the OS of patients who received AC (AC group) vs those who did not (non-AC group). Interactions between pathological findings and AC were investigated in separate multivariable Cox regression models. Results: In total, 1132 patients (mean [SD] age, 63.5 [9.4] years; 577 [50.1%] male; 970 [85.7%] White) were included, 640 patients in the non-AC group and 492 patients in the AC group. After being matched by propensity score according to demographic and pathological characteristics, 444 patients remained in each group. The multivariable Cox regression model adjusted for all covariates revealed an association between AC and improved survival (hazard ratio, 0.71; 95% CI, 0.59-0.85; P < .001). Subgroup interaction analysis revealed that AC was significantly associated with better OS (26.6 vs 21.2 months; P = .002), but the benefit varied by age, pathological T category, and tumor differentiation. Of note, AC was associated with better survival in patients with any pathological N category and positive margin status. Conclusions and Relevance: In this cohort study, AC following multiagent NAC and resection in patients with PDAC was associated with significant survival benefit compared with that in patients who did not receive AC. These findings suggest that patients with aggressive tumors may benefit from AC to achieve prolonged survival, even after multiagent NAC and curative-intent resection.

Factors associated with pancreatic cancer in Spain. What can we learn from epidemiological studies?

The incidence of pancreatic cancer (PC) in Spain has progressively increased over the past 6 decades. Pancreatic ductal adenocarcinoma represents over 80 % of all pancreatic neoplasms. The study by Enrique Gili-Ortiz on pancreatic cancer-related mortality trends in Spain revealed a significant increase in death rates in our country, which may be partly attributed to population ageing and increased smoking, obesity, and diabetes rates. Other known factors, including chronic pancreatitis, seem to play a less significant role from a quantitative perspective.

Subtypes in pancreatic ductal adenocarcinoma based on niche factor dependency show distinct drug treatment responses.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is characterized by abundant stroma in which microenvironmental (niche) factors promote PDAC progression. In mouse models, reduction of the stroma increased the proportion of poorly differentiated PDAC with a worse prognosis. Here, we aimed to clarify the effects of stroma on PDAC that may define the PDAC phenotype and induce distinct therapeutic responses. METHODS: The molecular features of PDAC based on differentiation grade were clarified by genome and transcriptome analysis using PDAC organoids (PDOs). We identified the dependency on niche factors that might regulate the differentiation grade. A three-dimensional co-culture model with cancer-associated fibroblasts (CAFs) was generated to determine whether CAFs provide niche factors essential for differentiated PDAC. PDOs were subtyped based on niche factor dependency, and the therapeutic responses for each subtype were compared. RESULTS: The expression profiles of PDOs differed depending on the differentiation grade. Consistent with the distinct profiles, well differentiated types showed high niche dependency, while poorly differentiated types showed low niche dependency. The three-dimensional co-culture model revealed that well differentiated PDOs were strongly dependent on CAFs for growth, and moderately differentiated PDOs showed plasticity to change morphology depending on CAFs. Differentiated PDOs upregulated the expression of mevalonate pathway-related genes correlated with the niche dependency and were more sensitive to simvastatin than poorly differentiated PDOs. CONCLUSIONS: Our findings suggest that CAFs maintain the differentiated PDAC phenotype through secreting niche factors and induce distinct drug responses. These results may lead to the development of novel subtype-based therapeutic strategies.

Prognostic signature based on m6A-related lncRNAs to predict overall survival in pancreatic ductal adenocarcinoma.

A growing body of evidence indicates that N6-methyladenosine (m6A) and long non-coding RNAs (lncRNAs) play crucial roles in the progression of PDAC and the treatment response of patients with pancreatic ductal adenocarcinoma (PDAC). In this study, we identified m6A-related lncRNAs to reveal their association with PDAC in prognosis and tumor immune environment. A prognostic signature based on 9 m6A-related lncRNAs was established, and the high-risk patients exhibited a significantly worse prognosis than low-risk patients. The predictive capacity was confirmed by receiver operating characteristic (ROC) curve analysis and an independent validation cohort. Correlation analyses revealed that m6A-related lncRNA signature was significantly associated with the number of somatic mutations, immunocyte infiltration, immune function, immune checkpoints, tumor microenvironment (TME) score, and sensitivity to chemotherapeutic drugs. Consequently, we constructed a highly accurate nomogram for improving clinical applicability of signature and exhibited superior predictive accuracy than both the signature and tumor stage. In conclusion, our proposed m6A-related lncRNA signature is a potential indicator predictive of prognosis and immunotherapeutic responses in PDAC patients.

Intratumor Microbiome Analysis Identifies Positive Association Between Megasphaera and Survival of Chinese Patients With Pancreatic Ductal Adenocarcinomas.

Human tumors harbor a plethora of microbiota. It has been shown that the composition and diversity of intratumor microbiome are significantly associated with the survival of patients with pancreatic ductal adenocarcinoma (PDAC). However, the association in Chinese patients as well as the effect of different microorganisms on inhibiting tumor growth are unclear. In this study, we collected tumor samples resected from long-term and short-term PDAC survivors and performed 16S rRNA amplicon sequencing. We found that the microbiome in samples with different survival time were significantly different, and the differential bacterial composition was associated with the metabolic pathways in the tumor microenvironment. Furthermore, administration of Megasphaera, one of the differential bacteria, induced a better tumor growth inhibition effect when combined with the immune checkpoint inhibitor anti-programmed cell death-1 (anti-PD-1) treatment in mice bearing 4T1 tumor. These results indicate that specific intratumor microbiome can enhance the anti-tumor effect in the host, laying a foundation for further clarifying the underlying detailed mechanism.