Lymph node metastases in resected pancreatic ductal adenocarcinoma: predictors of disease recurrence and survival

Construction and validation of novel nomograms based on the log odds of positive lymph nodes to predict the prognosis of papillary thyroid cancer: a retrospective cohort study

Objective

This study aims to assess the long-term prognostic significance of the log odds of positive lymph nodes (LODDS) in patients diagnosed with papillary thyroid cancer (PTC) and to develop a novel nomogram for predicting long-term overall survival (OS).

Methods

The cohort was randomly divided at a ratio of 7:3 from the Surveillance, Epidemiology, and End Results (SEER) database. Additionally, patient data from a medical center in China served as an external validation cohort. Nomograms were constructed using data from the training cohort and subsequently validated using both internal and external validation cohorts to predict 120- and 180-month OS in PTC patients. The predictive performance and clinical utility of the nomogram were assessed using various metrics, including the concordance index (C-index), time-dependent receiver operating characteristic (ROC) curves, calibration curves, decision curve analysis (DCA), Integrated Discriminant Improvement Index (IDI), and Net Reclassification Improvement Index (NRI).

Results

LODDS is an independent prognostic factor for PTC, a nomogram demonstrating high accuracy in predicting long-term OS. The C-index values, and time-dependent area under the curve (AUC) indicated well discriminatory ability of the nomogram. Calibration plots exhibited high concordance, while DCA, NRI, and IDI analyses revealed superior performance of the nomogram compared to AJCC staging system.

Conclusion

The clinical prediction model incorporating LODDS exhibits robust predictive performance, aiding in the assessment of long-term prognosis post-surgery in PTC patients. It serves as a valuable adjunct to the AJCC system, offering a scientific basis for guiding interventions and rehabilitation strategies for PTC patients following surgery.

Variation in lymph node assessment after pancreatic cancer resection: Patient, surgeon, pathologist, or hospital?

BACKGROUND

We sought to define individual contributions at the patient, surgeon, pathologist, and hospital levels on lymph node assessment after pancreatic cancer resection.

METHODS

SEER-Medicare beneficiaries who underwent pancreatic cancer resection were identified. Multi-level multivariable regression was performed to assess the proportion of variance explained by patient, surgeon, pathologist, and hospitals on lymph node assessment (≥12 versus <12).

RESULTS

2872 patients underwent pancreaticoduodenectomy by 646 distinct surgeons and 1063 distinct pathologists across 308 hospitals. Patient-related characteristics contributed the most to the variance in adequate lymph node assessment (71.0 ​%). After accounting for all explanatory variables in the full model, 5.5 ​% of the residual provider-level variation was attributed to the pathologist, 35.2 ​% to the surgeon, and 59.3 ​% to the hospital.

CONCLUSIONS

Patient-to-patient variation was the greatest underlying contributor to variations in adequate lymph node assessment related to pancreatic cancer surgery. Variation among hospitals was greater than among surgeons or pathologists.

Advantage of Log Odds of Metastatic Lymph Nodes After Curative-Intent Resection of Gallbladder Cancer

BACKGROUND

Lymph node metastasis (LNM) is among the most important predictors of poor prognosis after surgery for gallbladder cancer (GBC). Traditionally, staging has been based on the raw count of LNM, with a high risk of understaging patients who undergo inadequate lymph node dissection (LND). The log odds of metastatic lymph nodes (LODDS) may represent an alternative staging approach to stratify patients more accurately after resection of GBC.

PATIENTS AND METHODS

In this cross-sectional study, patients who underwent curative-intent surgery with LND for GBC were identified from an international database. Two predictive models were built and compared, each integrating a different lymph nodes status indicator [i.e., American Joint Committee on Cancer (AJCC) and LODDS].

RESULTS

Among 199 patients, the median number of lymph nodes examined was 5 [interquartile range (IQR): 3.0, 8.0]; most patients had T1 (n = 26, 13.1%) or T2 (n = 97, 48.7%) disease, and a subset had LNM (n = 87, 44.0%). Multivariable Cox analysis demonstrated LODDS was an independent predictor of overall survival [hazard ratio (HR) 1.84, 95% confidence interval (CI) 1.5-2.3; p < 0.001]. The LODDS model demonstrated better performance compared with a traditional model that utilized the AJCC N category [concordance (C) index: 0.814 versus 0.763; p < 0.001]. Patients classified as high- versus low-risk based on LODDS had much worse overall survival (OS) (4.9% versus 83.7%, respectively; p < 0.001). The LODDS model performance remained high even among patients with inadequate LND (< 6 LN) (C index: 0.87). An online calculator was developed ( https://catalano-giovanni.shinyapps.io/LoddsGBC/ ).

CONCLUSIONS

A novel prognostic model based on LODDS may overcome the inherent limitations of the current AJCC staging system, reducing understaging among patients with fewer than six total lymph nodes evaluated.

Survival Analysis of 4 Different Age Groups of Pancreatic Ductal Adenocarcinoma After Radical Resection From Retrospective Multi-Center Analysis (YPB-003)

AIM

This study aimed to investigate the efficacy of radical resection and postoperative adjuvant chemotherapy on the survival benefit in patients with pancreatic ductal adenocarcinoma (PDAC), stratified by age, frailty, and other factors in actual clinical practice.

METHODS

We retrospectively analyzed the clinicopathological and follow-up data of 414 patients with PDAC who underwent surgical resection at nine institutions under the Yamaguchi Pancreat/Biliary Disease Study Group, between January 1997 and December 2016. Recurrence-free survival (RFS) and overall survival (OS) were calculated using the Kaplan-Meier method. Associations between survival and prognostic factors were evaluated by univariate and multivariate analyses.

RESULTS

There were 30.5% of patients with PDAC who were aged < 65 years, 37.9% aged 65-74 years, 17.6% aged 75-79 years, and 14.0% aged ≥ 80 years. Notably, RFS declined with increasing age (median RFS: 12.9, 10.2, 9.4, and 7.4 months, respectively), although the differences were not significant (p = 0.223). OS significantly decreased with age (median OS: 21.6, 21.2, 17.0, and 13.9 months, respectively; p = 0.005). In patients aged < 75 years, independent prognostic factors identified by univariate and multivariate analyses included lymph node metastasis (hazard ratio [HR], 1.598; p = 0.007), tumor size (HR, 1.489; p = 0.043), R status (HR, 1.536; p = 0.011), and serum albumin levels (HR, 1.526; p = 0.031). In patients aged ≥ 75 years, a high modified frailty index (HR, 2.446; p = 0.012) emerged as an independent prognostic factor, along with lymph node metastasis, CA19-9 level (HR, 1.897; p = 0.017), and R status (HR, 2.087; p = 0.007).

CONCLUSION

The prognosis for older patients with PDAC was shorter than that of younger patients. Frailty may contribute to their poorer prognosis in older age.

Hypoxia Abrogates Tumor-Suppressive Activities of C/EBPδ in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is a dismal disease with a low 5-year survival rate of only 13%. Despite intense research efforts, PDAC remains insufficiently understood. In part, this is attributed to opposing effects of key players being unraveled, including the stroma but also molecules that act in a context-dependent manner. One such molecule is the transcription factor C/EBPδ, where we recently showed that C/EBPδ exerts tumor-suppressive effects in PDAC cells in vitro. To better understand the role of C/EBPδ in different contexts and the development of PDAC, we here build on these findings and assess the effect of C/EBPδ in a PDAC model in mice. We establish that the lack of oxygen in vivo-hypoxia-counteracts the tumor-suppressive effects of C/EBPδ, and identify a reciprocal feedback loop between C/EBPδ and HIF-1α. RNA sequencing of C/EBPδ-induced cells under hypoxia also suggests that the growth-limiting effects of C/EBPδ decrease with oxygen tension. Consequently, in vitro proliferation assays reveal that the tumor-suppressive activities of C/EBPδ are abrogated due to hypoxia. This study demonstrates the importance of considering major physiological parameters in preclinical approaches.

Radiogenomic analysis for predicting lymph node metastasis and molecular annotation of radiomic features in pancreatic cancer

BACKGROUND

To provide a preoperative prediction model for lymph node metastasis in pancreatic cancer patients and provide molecular information of key radiomic features.

METHODS

Two cohorts comprising 151 and 54 pancreatic cancer patients were included in the analysis. Radiomic features from the tumor region of interests were extracted by using PyRadiomics software. We used a framework that incorporated 10 machine learning algorithms and generated 77 combinations to construct radiomics-based models for lymph node metastasis prediction. Weighted gene coexpression network analysis (WGCNA) was subsequently performed to determine the relationships between gene expression levels and radiomic features. Molecular pathways enrichment analysis was performed to uncover the underlying molecular features.

RESULTS

Patients in the in-house cohort (mean age, 61.3 years ± 9.6 [SD]; 91 men [60%]) were separated into training (n = 105, 70%) and validation (n = 46, 30%) cohorts. A total of 1,239 features were extracted and subjected to machine learning algorithms. The 77 radiomic models showed moderate performance for predicting lymph node metastasis, and the combination of the StepGBM and Enet algorithms had the best performance in the training (AUC = 0.84, 95% CI = 0.77-0.91) and validation (AUC = 0.85, 95% CI = 0.73-0.98) cohorts. We determined that 15 features were core variables for lymph node metastasis. Proliferation-related processes may respond to the main molecular alterations underlying these features.

CONCLUSIONS

Machine learning-based radiomics could predict the status of lymph node metastasis in pancreatic cancer, which is associated with proliferation-related alterations.

A nomogram based on dual-layer detector spectral computed tomography quantitative parameters and morphological quantitative indicator for distinguishing metastatic and nonmetastatic regional lymph nodes in pancreatic ductal adenocarcinoma

Background

There is no unified scope for regional lymph node (LN) dissection in patients with pancreatic ductal adenocarcinoma (PDAC). Incomplete regional LN dissection can lead to postoperative recurrence, while blind expansion of the scope of regional LN dissection significantly increases the perioperative risk without significantly prolonging overall survival. We aimed to establish a noninvasive visualization tool based on dual-layer detector spectral computed tomography (DLCT) to predict the probability of regional LN metastasis in patients with PDAC.

Methods

A total of 163 regional LNs were reviewed and divided into a metastatic cohort (n=58 LNs) and nonmetastatic cohort (n=105 LNs). The DLCT quantitative parameters and the nodal ratio of the longest axis to the shortest axis (L/S) of the regional LNs were compared between the two cohorts. The DLCT quantitative parameters included the iodine concentration in the arterial phase (APIC), normalized iodine concentration in the arterial phase (APNIC), effective atomic number in the arterial phase (APZeff), normalized effective atomic number in the arterial phase (APNZeff), slope of the spectral attenuation curves in the arterial phase (APλHU), iodine concentration in the portal venous phase (PVPIC), normalized iodine concentration in the portal venous phase (PVPNIC), effective atomic number in the portal venous phase (PVPZeff), normalized effective atomic number in the portal venous phase (PVPNZeff), and slope of the spectral attenuation curves in the portal venous phase (PVPλHU). Logistic regression analysis based on area under the curve (AUC) was used to analyze the diagnostic performance of significant DLCT quantitative parameters, L/S, and the models combining significant DLCT quantitative parameters and L/S. A nomogram based on the models with highest diagnostic performance was developed as a predictor. The goodness of fit and clinical applicability of the nomogram were assessed through calibration curve and decision curve analysis (DCA).

Results

The combined model of APNIC + L/S (APNIC + L/S) had the highest diagnostic performance among all models, yielding an AUC, sensitivity, and specificity of 0.878 [95% confidence interval (CI): 0.825-0.931], 0.707, and 0.886, respectively. The calibration curve indicated that the APNIC-L/S nomogram had good agreement between the predicted probability and the actual probability. Meanwhile, the decision curve indicated that the APNIC-L/S nomogram could produce a greater net benefit than could the all- or-no-intervention strategy, with threshold probabilities ranging from 0.0 to 0.75.

Conclusions

As a valid and visual noninvasive prediction tool, the APNIC-L/S nomogram demonstrated favorable predictive efficacy for identifying metastatic LNs in patients with PDAC.

Construction and validation of log odds of positive lymph nodes (LODDS)-based nomograms for predicting overall survival and cancer-specific survival in ovarian clear cell carcinoma patients

Background

Ovarian clear cell carcinoma (OCCC) is one of the special histologic subtypes of ovarian cancer. This study aimed to construct and validate log odds of positive lymph nodes (LODDS)-based nomograms for predicting the overall survival (OS) and cancer-specific survival (CSS) in patients with OCCC.

Methods

Patients who underwent surgical treatment between 2010 and 2016 were extracted from the Surveillance Epidemiology and End Results (SEER) database and the data of OCCC patients from the First Affiliated Hospital of Dalian Medical University were used as the external validation group to test the validity of the prognostic model. The best-fitting models were selected by stepwise Cox regression analysis. Survival probability was calculated by the Kaplan-Meier method, and the differences in survival time between subgroups were compared using the log-rank test. Each nomogram's performance was assessed by the calibration plots, decision curve analysis (DCA), and receiver operating characteristics (ROC) curves.

Results

T stage, distant metastasis, marital status, and LODDS were identified as significant risk factors for OS. A model with four risk factors (age, T stage, stage, and LODDS value) was obtained for CSS. Nomograms were constructed by incorporating the prognostic factors to predict 1-, 3- and 5-year OS and CSS for OCCC patients, respectively. The area under the curve (AUC) range of our nomogram model for OS and CSS prediction ranged from 0.738-0.771 and 0.769-0.794, respectively, in the training cohort. The performance of this model was verified in the internal and external validation cohorts. Calibration plots illustrated nomograms have good prognostic reliability.

Conclusion

Predictive nomograms were constructed and validated to evaluate the OS and CSS of OCCC patients. These nomograms may provide valuable prognostic information and guide postoperative personalized care in OCCC.

Extended lymphadenectomy based on the TRIANGLE for pancreatic head cancer: a single-center experience

BACKGROUND

This study was to compare the safety and efficacy of different lymphadenectomy methods in patients with pancreatic head cancer undergoing pancreaticoduodenectomy (PD).

MATERIAL AND METHODS

A total of 150 patients were included in this study. Patients were divided into Group A (n = 79), Group B (n = 44), and Group C (n = 27) according to the different lymphadenectomy methods. The clinical endpoint was time to progression (TTP) and overall survival (OS). Postoperative complications of different lymphadenectomy methods were compared respectively. TTP and OS of the three groups were compared by Kaplan-Meier curves.

RESULTS

There were no significant differences between the three groups in operative time (P = 0.300), death in the hospital (P = 0.253), postoperative hemorrhage (P = 0.863), postoperative pancreatic fistula (POPF) B/C (P = 0.306), bile leakage (P = 0.215), intestinal fistula (P = 0.177), lymphatic leakage (P = 0.267), delayed gastric emptying [(DGE) (P = 0.283)], ICU stay (P = 0.506), and postoperative hospital stay [(PHS) (P = 0.810)]. Median TTP in Groups B and C was significantly longer than in Group A (log-rank test, A vs B: P = 0.0005, A vs C: P = 0.0001). Median OS between the three groups has no statistical difference (P = 0.1546).

CONCLUSIONS

Extended lymphadenectomy methods based on the TRIANGLE do not increase perioperative complications significantly and can effectively delay tumor progression in patients with pancreatic head cancer.

18F-FAPI-04 Outperforms 18F-FDG PET/CT in Clinical Assessments of Patients with Pancreatic Adenocarcinoma

Accurate diagnosis and staging are crucial for selecting treatment for patients with pancreatic ductal adenocarcinoma (PDAC). The desmoplastic responses associated with PDAC are often characterized by hypometabolism. Here, we investigated 18F-fibroblast activation protein inhibitor (FAPI)-04 PET/CT in evaluation of PDAC and compared the findings with those obtained using 18F-FDG. Methods: Sixty-two PDAC patients underwent 18F-FAPI-04 PET/CT and 18F-FDG PET/CT. Identification of primary lesions, lymph node (LN) metastasis, and distant metastasis (DM) by these methods was evaluated, and TNM staging was performed. Correlation between SUVmax of the primary lesion and treatment response was explored in patients who received systemic therapy. Results: 18F-FAPI-04 PET/CT identified all patients with PDAC; 18F-FDG PET/CT missed 1 patient. Tracer uptake was higher in 18F-FAPI-04 PET/CT than in 18F-FDG PET/CT in primary tumors (10.63 vs. 2.87, P < 0.0001), LN metastasis (2.90 vs. 1.43, P < 0.0001), and DM (liver, 6.11 vs. 3.10, P = 0.002; peritoneal, 4.70 vs. 2.08, P = 0.015). The methods showed no significant difference in the T staging category, but the N and M values were significantly higher for 18F-FAPI-04 PET/CT than for 18F-FDG PET/CT (P = 0.002 and 0.008, respectively). Thus, 14 patients were upgraded, and only 1 patient was downgraded, by 18F-FAPI-04 PET/CT compared with 18F-FDG PET/CT. A high SUVmax of the primary tumor did not correlate with treatment response for either 18F-FAPI-04 or 18F-FDG. Conclusion: 18F-FAPI-04 PET/CT performed better than 18F-FDG PET/CT in identification of primary tumors, LN metastasis, and DM and in TNM staging of PDAC.

Anatomical and Biological Considerations to Determine Resectability in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) remains associated with poor outcomes with a 5-year survival of 12% across all stages of the disease. These poor outcomes are driven by a delay in diagnosis and an early propensity for systemic dissemination of the disease. Recently, aggressive surgical approaches involving complex vascular resections and reconstructions have become more common, thus allowing more locally advanced tumors to be resected. Unfortunately, however, even after the completion of surgery and systemic therapy, approximately 40% of patients experience early recurrence of disease. To determine resectability, many institutions utilize anatomical staging systems based on the presence and extent of vascular involvement of major abdominal vessels around the pancreas. However, these classification systems are based on anatomical considerations only and do not factor in the burden of systemic disease. By integrating the biological criteria, we possibly could avoid futile resections often associated with significant morbidity. Especially patients with anatomically resectable disease who have a heavy burden of radiologically undetected systemic disease most likely do not derive a survival benefit from resection. On the contrary, we could offer complex resections to those who have locally advanced or oligometastatic disease but have favorable systemic biology and are most likely to benefit from resection. This review summarizes the current literature on defining anatomical and biological resectability in patients with pancreatic cancer.

KRAS-related miR-143 expression is associated with lymph node involvement and correlates with outcome in pancreatic adenocarcinoma patients

Introduction

Pancreatic adenocarcinoma (PC) is one of the most lethal malignancies; even after resection the patients' 5-year disease-free survival (DFS) is lower than 26%. The genetic mutational landscape of PC is dominated by activating KRAS mutations, that have been reported in approximately 90% of cases; however, beyond KRAS - direct mutations, several KRAS-targeting miRNAs appear to be downregulated, strengthening the already activated RAS signaling. In addition, the interplay between miRNAs and RAS includes poorly investigated downstream miRNAs. The aim of this study was to determine the prognostic value of some of these candidate KRAS-related miRNAs.

Patients and methods

Between 2015 and 2022, 44 patients with pathologically confirmed PC, who received surgery and were enrolled by the Clinical Oncology Unit, Careggi University Hospital, Florence (Italy). PC Total RNA was extracted from FFPE sections, retro-transcribed and the resulting cDNA was then used for qPCR analysis. A panel of KRAS-related miRNA (miR-155, miR-206 and miR-143) was analyzed.

Results

In this observational study patients sex distribution was unequal with 34.1% being male and 65.9% female. The most frequent tumor localization was the head of the pancreas (65.9%) and the pathological stages were pT1-2 (45.5%), pT3 (54.5%), pN0 (22.7%), pN+ (77.3%). Adjuvant therapy was administered to 63.6% of patients; disease recurrence was observed in 69% of cases. Twenty-three patients, whose RNA was of adequate quality, were used in the mRNAs expression studies. When comparing the miRNA expression between PC and a pool of healthy tissues, miR-155 was overexpressed and miR-206 downregulated in PC, while miR-143 expression was unchanged. However, when categorized in low- and high- miR-143 expressing PC (according to the median value), high miR-143 was associated with nodal involvement (pN+) (p=0.029), who in turn was linked with shorter DFS (p=0.009) and overall survival (OS) (p=0.021) compared to pN0. A trend toward inferior DFS was observed for higher expression of miR-206 (p=0.095) and miR-143 (p=0.092). Finally, responders to a first-line treatment for advanced disease had miR-155 overexpressed (p=0.048).

Conclusions

miRNAs are involved in PC tumorigenesis and metastatic spread. In light of miR-143 association with lymphatic spread and poor prognosis, a comprehensive analysis of miRNA interplay with KRAS deserves further investigation.

Portomesenteric venous contact ≤180° and overall survival in resectable head and body pancreatic adenocarcinoma treated with upfront surgery

INTRODUCTION

Upfront surgery is the standard of care for resectable pancreatic cancer, defined as the absence of or ≤180° tumour contact with the portal/superior mesenteric vein. We hypothesized that portomesenteric venous tumour contact is prognostically unfavourable and aimed to assess whether it is associated with poorer survival compared with no venous contact in resectable head and body pancreatic cancer.

METHODS

This single-centre retrospective study included patients undergoing upfront surgery for resectable head and body pancreatic cancer in 2010-2020 at Umeå University Hospital, Sweden. No venous contact was compared with portomesenteric venous contact of ≤180° based on preoperative imaging. Overall survival on an intention-to-treat basis was compared with Kaplan-Meier curves, a log-rank test and Cox proportional hazards models.

RESULTS

The final study cohort included 39 patients with portomesenteric venous tumour contact and 144 patients without venous tumour contact. Patients with venous tumour contact had a median overall survival of 15.3 months compared to 23.0 months (log rank P = 0.059). Portomesenteric venous tumour contact was an independent negative prognostic factor for survival in the multivariable Cox model (HR 1.68; 95% CI 1.11-2.55, P = 0.014) and was associated with higher rates of microscopically non-radical resections (R1) (50% vs 26.1%, P = 0.012) and pathological lymph node metastasis (76.7% vs 56.8%, P = 0.012). There was no difference in adjuvant chemotherapy receipt or postoperative complications between the groups.

CONCLUSIONS

Portomesenteric venous tumour contact is associated with poorer overall survival and higher rates of R1 resections and lymph node metastasis in patients with resectable head and body pancreatic cancer treated with upfront surgery.

Analysis of Risk Factors for Distant Metastasis of Pancreatic Ductal Adenocarcinoma without Regional Lymph Node Metastasis and a Nomogram Prediction Model for Survival

Background

Negative regional lymph nodes do not indicate a lack of distant metastasis. A considerable number of patients with negative regional lymph node pancreatic cancer will skip the step of regional lymph node metastasis and directly develop distant metastasis.

Methods

We retrospectively analyzed the clinicopathological characteristics of patients with negative regional lymph node pancreatic cancer and distant metastasis in the Surveillance, Epidemiology, and End Results database from 2010 to 2015. Multivariate logistic analysis and Cox analysis were used to determine the independent risk factors that promoted distant metastasis and the 1-, 2-, and 3-year cancer-specific survival in this subgroup.

Results

Sex, age, pathological grade, surgery, radiotherapy, race, tumor location, and tumor size were significantly correlated with distant metastasis (P < 0.05). Among these factors, pathological grade II and above, tumor site other than the pancreatic head, and tumor size >40 mm were independent risk factors for distant metastasis; age ≥60 years, tumor size ≤21 mm, surgery, and radiation were protective factors against distant metastasis. Age, pathological grade, surgery, chemotherapy, and metastasis site were identified as predictors of survival. Among them, age ≥40 years, pathological grade II and above, and multiple distant metastasis were considered independent risk factors for cancer-specific survival. Surgery and chemotherapy were considered protective factors for cancer-specific survival. The prediction performance of the nomogram was significantly better than that of the traditional American Joint Committee on Cancer tumor, node, metastasis staging system. We also established an online dynamic nomogram calculator, which can predict the survival rate of patients at different follow-up time points.

Conclusion

Pathological grade, tumor location, and tumor size were independent risk factors for distant metastasis in pancreatic ductal adenocarcinoma with negative regional lymph nodes. Older age, smaller tumor size, surgery, and radiotherapy were protective factors against distant metastasis. A new nomogram that was constructed could effectively predict cancer-specific survival in pancreatic ductal adenocarcinoma with negative regional lymph nodes and distant metastasis. Furthermore, an online dynamic nomogram calculator was established.

C/EBP-Family Redundancy Determines Patient Survival and Lymph Node Involvement in PDAC

Pancreatic ductal adenocarcinoma (PDAC) is a dismal disease with a poor clinical prognosis and unsatisfactory treatment options. We previously found that the transcription factor CCAAT/Enhancer-Binding Protein Delta (C/EBPδ) is lowly expressed in PDAC compared to healthy pancreas duct cells, and that patient survival and lymph node involvement in PDAC is correlated with the expression of C/EBPδ in primary tumor cells. C/EBPδ shares a homologous DNA-binding sequence with other C/EBP-proteins, leading to the presumption that other C/EBP-family members might act redundantly and compensate for the loss of C/EBPδ. This implies that patient stratification could be improved when expression levels of multiple C/EBP-family members are considered simultaneously. In this study, we assessed whether the quantification of C/EBPβ or C/EBPγ in addition to that of C/EBPδ might improve the prediction of patient survival and lymph node involvement using a cohort of 68 resectable PDAC patients. Using Kaplan-Meier analyses of patient groups with different C/EBP-expression levels, we found that both C/EBPβ and C/EBPγ can partially compensate for low C/EBPδ and improve patient survival. Further, we uncovered C/EBPβ as a novel predictor of a decreased likelihood of lymph node involvement in PDAC, and found that C/EBPβ and C/EBPδ can compensate for the lack of each other in order to reduce the risk of lymph node involvement. C/EBPγ, on the other hand, appears to promote lymph node involvement in the absence of C/EBPδ. Altogether, our results show that the redundancy of C/EBP-family members might have a profound influence on clinical prognoses and that the expression of both C/EPBβ and C/EBPγ should be taken into account when dichotomizing patients according to C/EBPδ expression.

Reevaluation of regional lymph nodes in patients with pancreatic ductal adenocarcinoma in the pancreatic body and tail

Introduction

In patients with pancreatic ductal adenocarcinoma (PDAC) in the pancreatic body (Pb) and tail (Pt), the appropriate area for lymphadenectomy is controversial. This study aimed to reevaluate the extent of lymph node (LN) metastasis in Pb- and Pt-PDAC, and to define the optimal area of LN dissection.

Patients and methods

This single-center retrospective study evaluated patients with Pb- and Pt-PDAC who underwent distal pancreatectomy with extended lymphadenectomy between 2006 and 2020. LN metastasis in >3.0% of patients were defined as new regional LN.

Results

The study cohort included 135 patients with Pb-PDAC and 42 patients with Pt-PDAC. In patients with Pb-PDAC, LNs around the splenic artery (SPA) had the highest metastasis-positive rate (54.1%). LNs along the left gastric artery, common hepatic artery, celiac axis (CA), superior mesenteric artery (SMA), and splenic hilus were defined as new regional LNs. In patients with Pt-PDAC, LNs at the splenic hilum had the highest metastasis-positive rate (38.1%). The station and LN around the SPA were defined as new regional LNs in those with Pt-PDAC. Metastasis beyond the newly defined regional LNs was not associated with survival. The incidence of LN metastasis was lower in patients who received preoperative chemotherapy than in those who underwent upfront surgery in both Pb- and Pt-PDAC.

Conclusion

Although it needs to be verified in future multicenter studies, LN of both the CA and SMA systems should be dissected in patients with Pb-PDAC. However, only those around the SPA and splenic hilus should be dissected routinely in those with Pt-PDAC.

Comparing the predictive performance of different lymph node staging systems for postoperative overall survival in patients with ampullary carcinoma

Aim

This study was to analyze and compare the predictive performance of the 7th and the 8th edition American Joint Committee on Cancer (AJCC) N staging system, lymph nodes ratio (LNR) and log odds of positive lymph node (LODDS) for the survival of patients with ampullary carcinomas (ACs).

Method

This retrospective cohort study included patients with primary ACs after surgery from the Surveillance, Epidemiology, and End Results (SEER) 2004-2015. Univariate and multivariate Cox proportional hazard models were used. The study population was divided into a training set and a testing set in a ratio of 7-3. The C-index and area under the curve (AUC) were used to compare the predictive performance of the four staging on overall survival (OS) in the training set and the testing set.

Results

A total of 7,480 patients with primary ACs (1,178 survived and 1,128 dead) were in this study. The average follow-up time was 41.1 months. N1 stage and N2 stage of the 8th edition AJCC N staging system, LNR staging (0-0.3), LNR (>0.3), LODDS (-2.4 to -0.8) and LODDS (>-0.8) were associated with OS in AC patients after adjusting for age, race, pT stage, tumor size, grade, radiation, and insurance. The C-index of the 7th AJCC N staging was significantly lower than the C-index of the 8th AJCC N staging in the training set [0.608 vs. 0.629, P < 0.001] and testing set [0.635 vs. 0.658, P < 0.001]. The C-index of the LODDS staging was significantly higher than the C-index of the 8th AJCC N staging in the training set [0.641 vs. 0.629, P = 0.034] and testing set [0.671 vs. 0.658, P = 0.034]. LODDS staging may be a potential predictor of OS at 6 months [AUC = 0.687], 12 months (AUC = 0.692), and 48 months (AUC = 0.709), and LNR staging (AUC = 0.655) may be a potential predictor of OS at 24 months in AC patients. The predictive ability of LNR staging and LODDS staging were also found in different subgroups.

Conclusion

The LNR and LODDS staging systems' predictive performance for OS of AC patients were superior to the 8th edition AJCC N staging system, especially in patients ages ≥65 or with higher tumor grade (grade II and III). The LNR staging and the LODDS staging were potential predictors for 24-month OS, and 6, 12, 24 and 48-month OS, respectively.

Pathological Response Predicts Survival after Pancreatectomy following Neoadjuvant FOLFIRINOX for Pancreatic Cancer

Background: The clinical course of complete pathologic response (cPR) in pancreatic cancer after neoadjuvant chemotherapy is not well known. The aim of this study was to investigate the clinical course of patients according to pathological response, including cPR, who received only FOLIFIRNOX in advanced pancreatic cancer. Methods: Patients who underwent pancreatectomy after FOLFIRINOX for pancreatic ductal adenocarcinoma (PDAC) from 2017 to 2019 were retrospectively reviewed. cPR was defined as an absence of residual tumor on pathologic report. A nearly complete pathologic response (ncPR) was defined as a tumor confined to pancreas parenchyma, less than 1 cm without lymph-node metastasis. cPR and ncPR were assigned into a favorable pathologic response group (fPR). Kaplan−Meier method and Cox proportional hazard models were used for analysis. Results: Of a total 64 patients, 8 (12.5%) had a cPR and 8 (12.5%) had a ncPR. In the fPR group, median OS and DFS were superior to those of non-pathologic response group (more than 60 months vs. 38 months, p < 0.001; more than 42 months vs. 10 months, p < 0.001). On multivariable analyses, fPR and adjuvant therapy were independent prognostic factors for OS (HR: 0.12; 95% CI: 0.02−0.96, p = 0.05; HR: 0.26; 95% CI: 0.09−0.74, p = 0.01) and DFS (HR: 0.31; 95% CI: 0.12−0.86, p = 0.02; HR:0.31; 95% CI: 0.13−0.72, p = 0.01). Conclusions: pathologic response predicts survival after pancreatectomy following neoadjuvant FOLFIRINOX for pancreatic cancer, and adjuvant chemotherapy following neoadjuvant treatment might be beneficial for OS and DFS.

Impact of Sarcopenia on Patients with Localized Pancreatic Ductal Adenocarcinoma Receiving FOLFIRINOX or Gemcitabine as Adjuvant Chemotherapy

Background: Despite its toxicity, modified FOLFIRINOX is the main chemotherapy for localized, operable pancreatic adenocarcinomas. Sarcopenia is known as a factor in lower overall survival (OS). The purpose of this study was to assess the impact of sarcopenia on OS in patients with localized pancreatic ductal adenocarcinoma (PDAC) who received modified FOLFIRINOX or gemcitabine as adjuvant chemotherapy. Methods: Patients with operated PDAC who received gemcitabine-based (GEM group) or oxaliplatin-based (OXA group) adjuvant chemotherapy between 2008 and 2021 were retrospectively included. Sarcopenia was estimated on a baseline computed tomography (CT) examination using the skeletal muscular index (SMI). The primary evaluation criterion was OS. Secondary evaluation criteria were disease-free survival (DFS) and toxicity. Results: Seventy patients treated with gemcitabine-based (n = 49) and oxaliplatin-based (n = 21) chemotherapy were included, with a total of fifteen sarcopenic patients (eight in the GEM group and seven in the OXA group). The median OS was shorter in sarcopenic patients (25 months) compared to non-sarcopenic patients (158 months) (p = 0.01). A longer OS was observed in GEM non-sarcopenic patients (158 months) compared to OXA sarcopenic patients (14.4 months) (p < 0.01). The median OS was 157.7 months in the GEM group vs. 34.1 months in the OXA group (p = 0.13). No differences in median DFS were found between the GEM group and OXA group. More toxicity events were observed in the OXA group (50%) than in the GEM group (10%), including vomiting (p = 0.02), mucositis (p = 0.01) and neuropathy (p = 0.01). Conclusion: Sarcopenia is associated with a worse prognosis in patients with localized operated PDAC whatever the delivered adjuvant chemotherapy.

Machine-learning based investigation of prognostic indicators for oncological outcome of pancreatic ductal adenocarcinoma

Introduction

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with a poor prognosis. Surgical resection remains the only potential curative treatment option for early-stage resectable PDAC. Patients with locally advanced or micrometastatic disease should ideally undergo neoadjuvant therapy prior to surgical resection for an optimal treatment outcome. Computerized tomography (CT) scan is the most common imaging modality obtained prior to surgery. However, the ability of CT scans to assess the nodal status and resectability remains suboptimal and depends heavily on physician experience. Improved preoperative radiographic tumor staging with the prediction of postoperative margin and the lymph node status could have important implications in treatment sequencing. This paper proposes a novel machine learning predictive model, utilizing a three-dimensional convoluted neural network (3D-CNN), to reliably predict the presence of lymph node metastasis and the postoperative positive margin status based on preoperative CT scans.

Methods

A total of 881 CT scans were obtained from 110 patients with PDAC. Patients and images were separated into training and validation groups for both lymph node and margin prediction studies. Per-scan analysis and per-patient analysis (utilizing majority voting method) were performed.

Results

For a lymph node prediction 3D-CNN model, accuracy was 90% for per-patient analysis and 75% for per-scan analysis. For a postoperative margin prediction 3D-CNN model, accuracy was 81% for per-patient analysis and 76% for per-scan analysis.

Discussion

This paper provides a proof of concept that utilizing radiomics and the 3D-CNN deep learning framework may be used preoperatively to improve the prediction of positive resection margins as well as the presence of lymph node metastatic disease. Further investigations should be performed with larger cohorts to increase the generalizability of this model; however, there is a great promise in the use of convoluted neural networks to assist clinicians with treatment selection for patients with PDAC.

A randomized, phase II trial of oral azacitidine (CC-486) in patients with resected pancreatic adenocarcinoma at high risk for recurrence

BACKGROUND

Of the only 20% of patients with resectable pancreatic ductal adenocarcinoma (rPDA), cancer recurs in 80% of cases. Epigenetic dysregulation is an early hallmark of cancer cells acquiring metastatic potential, and epigenetic modulators may reactivate tumor suppressor genes, delay recurrence, and sensitize PDA to future chemotherapy.

METHODS

This was a randomized phase II study (NCT01845805) of CC-486 (oral DNA methyltransferase inhibitor azacitidine) vs. observation (OBS) in rPDA patients harboring high-risk features (stage pN1-2, R1 margins, or elevated CA 19-9 level) with no evidence of disease following standard adjuvant therapy. Patients were randomized to oral CC-486 treatment (300 mg daily on days 1-21 on a 28-day cycle) or OBS for up to 12 cycles or until disease relapse/unacceptable toxicities. Following recurrence, records of next-line therapies, imaging, and survival were obtained. The primary endpoint was progression-free survival (PFS)-time from randomization to recurrence (imaging/biopsy confirmed or death). Secondary endpoints included OS and PFS and ORR and metastatic PFS with subsequent next-line systemic therapy in metastatic setting.

RESULTS

Forty-nine patients (24 in CC-486 arm, 25 in OBS arm) were randomized: median age 66 (range 36-81), 53% male, 73% node positive, 49% elevated CA 19-9, 20% R1 resection, 63% and 100% received perioperative concurrent chemoradiation and chemotherapy, respectively. Median time from surgery to randomization was 9.6 mo (range 2.9-36.8). For the CC-486 arm, median treatment duration was 5.6 mo (range 1.3 to 12.8) with 14 treatment-related grade 3 or 4 AEs among 5 patients (22%) resulting in dose-reduction. Four patients (17%) discontinued therapy due to AEs. With median follow-up of 20.3mo (IQR 12.8, 41.4), 38 (79%) of evaluable patients recurred (34 imaging-confirmed, 4 clinically). Median PFS in imagining-confirmed cases was 9.2 and 8.9mo (HR 0.94, 95% CI 0.46-1.87, p = 0.85) for CC-486 and OBS patients, respectively. Median OS (2-yr OS%) was 33.8 (50%) and 26.4 mo (61%) in CC-486 and OBS patients, respectively. (HR 0.98, 95% CI 0.46-2.05, p = 0.96). ORR with subsequent chemotherapy in the metastatic setting was minimal in both arms.

CONCLUSIONS

Treatment with CC-486 following adjuvant therapy did not prolong time-to-relapse in patients with high-risk rPDA or improve disease response on 1st-line metastatic therapy.

Possibility of Neoadjuvant Treatment for Radiologically Judged Resectable Pancreatic Cancer

Survival remains poor even after resection of pancreatic cancer and the postoperative recurrence rate is extremely high. Thus, neoadjuvant treatment may improve outcomes for resectable pancreatic cancer (RPC). This study evaluated the efficacy of neoadjuvant therapy for radiologically judged RPC. A prospectively maintained institutional database was reviewed to identify patients who underwent potentially curative resection of radiologically judged RPC. Patient characteristics and intermediate-term outcomes were compared between groups that received neoadjuvant treatment or upfront surgery (UFS). We identified 353 eligible patients, including 55 patients who received neoadjuvant chemoradiotherapy (CRT group), 53 patients who received neoadjuvant gemcitabine plus nab-paclitaxel (GnP group), and 245 patients who underwent UFS (UFS group). The cumulative rates of pancreatic cancer recurrence at 2 years after pancreatic surgery were 49.5% in the UFS, 48.1% in the CRT group, and 52.7% in the GnP group. The recurrence rate tended to be improved after neoadjuvant treatment, although the difference was not significant at this follow-up point. While the clinical TNM classifications were noticeably different from the final pathological findings, the clinical and pathological TNM classifications were more similar in the groups that underwent neoadjuvant treatment. Neoadjuvant treatment can help identify good surgical candidates and avoid unnecessary laparotomy. Our results also suggest that neoadjuvant therapy might help improve the preoperative diagnostic accuracy for patients with RPC.

Evaluation of the 8th Edition AJCC Staging System for the Clinical Staging of Pancreatic Cancer

The 8th edition of the American Joint Committee on Cancer (AJCC) staging system for pancreatic cancer (PC) has been validated for pathological staging; however, its significance for clinical staging remains uncertain. We validated the prognostic performance and suitability of the current staging system for the clinical staging of PC. We identified 1043 patients from our PC registry who were staged by imaging according to the 8th edition staging system and conducted analysis, including overall survival (OS) comparison. Gradual prognostic stratification according to stage hierarchy yielded significant OS differences between stage groups, except between stage I and II (p = 0.193). A substage comparison revealed no survival differences between IB (T2N0) and IIA (T3N0), which were divided by the T3 criterion only (p = 0.278). A higher N stage had significantly shorter OS than a lower N stage (all pairwise p < 0.05). However, among the 150 patients who received upfront surgery, the pathological stage was more advanced than the clinical stage in 86 (57.3%), mostly due to a false-negative cN0 (70.9%). Our results suggest that the new definition of T3 and the number-based N criteria in the 8th edition AJCC staging system may be not adequate for clinical staging. Establishing separate criteria more suitable for clinical staging should be considered.

The effect of minimally invasive or open radical antegrade modular pancreatosplenectomy on pancreatic cancer: A multicenter randomized clinical trial protocol

Background

Radical antegrade modular pancreatosplenectomy (RAMPS) has been proven to improve R0 resection and lymph harvest in treating patients with distal pancreatic cancer. The development of minimally invasive surgery has advantages in postoperative recovery. Therefore, minimally invasive (MI-) RAMPS may combine the advantages of both benefits to improve survival. Nevertheless, evidence to validate the safety and efficacy of MI-RAMPS is limited.

Method/Design

The MIRROR trial will be the first multicenter prospective randomized clinical trial to investigate the outcome of MI-RAMPS. The hypothesis is that MI-RAMPS is superior in postoperative recovery. The primary outcome is the length of postoperative stay. Based on the hypothesis and primary outcome, the sample size is 250 patients (125 participants in each group). The trial will investigate factors related to surgical safety, short-term outcome, pathological assessment, and survival as secondary outcomes.

Conclusion

This study will offer a relatively higher level of evidence to further illustrate the accessibility and benefits of MI-RAMPS for the treatment of distal pancreatic cancer.

Clinical Trial Registration

Clinicaltrials.gov, NCT03770559.

Efficacy and safety of laparoscopic radical resection following neoadjuvant therapy for pancreatic ductal adenocarcinoma: A retrospective study

BACKGROUND

Multiple studies have demonstrated that neoadjuvant chemotherapy (NACT) can prolong the overall survival of pancreatic ductal adenocarcinoma (PDAC) patients. However, most studies have focused on open surgery following NACT.

AIM

To investigate the efficacy and safety of laparoscopic radical resection following NACT for PDAC.

METHODS

We retrospectively analyzed the clinical data of 15 patients with pathologically confirmed PDAC who received NACT followed by laparoscopic radical surgery in our hospital from December 2019 to April 2022. All patients underwent abdominal contrast-enhanced computed tomography (CT) and positron emission tomography-CT before surgery to accurately assess tumor stage and exclude distant metastasis.

RESULTS

All 15 patients with pancreatic cancer were successfully converted to surgical resection after NACT, including 8 patients with pancreatic head cancer and 7 patients with pancreatic body and tail cancer. Among them, 13 patients received the nab-paclitaxel plus gemcitabine regimen (gemcitabine 1000 mg/m2 plus nab-paclitaxel 125 mg/m2 on days 1, 8, and 15 every 4 wk) and 2 patients received the modified FOLFIRINOX regimen (intravenous oxaliplatin 68 mg/m2, irinotecan 135 mg/m2, and leucovorin 400 mg/m2 on day 1 and fluorouracil 400 mg/m2 on day 1, followed by 46-h continuous infusion of fluorouracil 2400 mg/m2). After each treatment cycle, abdominal CT, tumor markers, and circulating tumor cell counts were reviewed to evaluate the treatment efficacy. All 15 patients achieved partial remission. The surgical procedures included laparoscopic pancreaticoduodenectomy (LPD, n = 8) and laparoscopic radical antegrade modular pancreatosplenectomy (L-RAMPS, n = 7). None of them were converted to a laparotomy. One patient with pancreatic head carcinoma was found to have portal vein involvement during the operation, and LPD combined with vascular resection and reconstruction was performed. The amount of blood loss and operation times of L-RAMPS vs LPD were 435.71 ± 32.37 mL vs 343.75 ± 145.01 mL and 272.52 ± 49.14 min vs 444.38 ± 68.63 min, respectively. The number of dissected lymph nodes was 16.87 ± 4.10, and 3 patients had positive lymph nodes. One patient developed grade B postoperative pancreatic fistula (POPF) after L-RAMPS, and one patient experienced jaundice after LPD. None of the patients died after surgery. As of April 2022, progressive disease was noted in 4 patients, 2 patients had liver metastasis, and one had both liver metastasis and lymph node metastasis and died during the follow-up period.

CONCLUSION

Laparoscopic radical resection of PDAC after NACT is safe and effective if it is performed by a surgeon with rich experience in LPD and in a large center of pancreatic surgery.

Optimal lymph-node dissection for pancreatic tail cancer

PURPOSE

The optimal range of lymph-node dissection for pancreatic tail cancer remains unclear. We investigated the location and frequency of lymph-node metastases to identify the correct range of lymph-node dissection for pancreatic tail cancer.

METHODS

We analyzed clinical data retrospectively, on patients who underwent distal pancreatectomy for resectable left-sided pancreatic cancer, between February, 2006 and March, 2021. Eligible patients were divided into two groups according to the tumor location: those with pancreatic tail cancer (Pt group) and those with pancreatic body or body and tail cancer (non-Pt group).

RESULTS

Of the 96 patients analyzed, 61 (64%) were assigned to the Pt group and 35 (36%) were assigned to the non-Pt group. Metastases to stations 7, 8, 9, 10, 11, 14, and 18 were found in 0 (0%), 0 (0%), 0 (0%), 4 (7%), 18 (30%), 2 (4%), and 10 (17%) patients in the Pt group, and in 1 (3%), 4 (12%), 2 (6%), 1 (3%), 18 (51%), 3 (9%), and 6 (17%) patients in the non-Pt group, respectively.

CONCLUSION

Lymph-node dissection at stations 7, 8, and 9 might not be necessary in patients with resectable pancreatic cancer confined to the pancreatic tail.

Establishment of a multi-parameters MRI model for predicting small lymph nodes metastases (<10 mm) in patients with resected pancreatic ductal adenocarcinoma

PURPOSE

To evaluate the potential role of MR findings and DWI parameters in predicting small regional lymph nodes metastases (with short-axis diameter < 10 mm) in pancreatic ductal adenocarcinomas (PDACs).

METHODS

A total of 127 patients, 82 in training group and 45 in testing group, with histopathologically diagnosed PDACs who underwent pancreatectomy were retrospectively analyzed. PDACs were divided into two groups of positive and negative lymph node metastases (LNM) based on the pathological results. Pancreatic cancer characteristics, short axis of largest lymph node, and DWI parameters of PDACs were evaluated.

RESULTS

Univariate and multivariate analyses showed that extrapancreatic distance of tumor invasion, short-axis diameter of the largest lymph node, and mean diffusivity of tumor were independently associated with small LNM in patients with PDACs. The combining MRI diagnostic model yielded AUCs of 0.836 and 0.873, and accuracies of 81.7% and 80% in the training and testing groups. The AUC of the MRI model for predicting LNM was higher than that of subjective MRI diagnosis in the training group (rater 1, P = 0.01; rater 2, 0.008) and in a testing group (rater 1, P = 0.036; rater 2, 0.024). Comparing the subjective diagnosis, the error rate of the MRI model was decreased. The defined LNM-positive group by the MRI model showed significantly inferior overall survival compared to the negative group (P = 0.006).

CONCLUSIONS

The MRI model showed excellent performance for individualized and noninvasive prediction of small regional LNM in PDACs. It may be used to identify PDACs with small LNM and contribute to determining an appropriate treatment strategy for PDACs.

N, LNR or LODDS: Which Is the Most Appropriate Lymph Node Classification Scheme for Patients with Radically Resected Pancreatic Cancer?

Simple Summary

To date, no data are available regarding the most appropriate alternative LN classification system with respect to prognostic power and discriminative ability in cases with resectable pancreatic ductal adenocarcinoma (PDAC). We compared different lymph node classification systems with regard to accurate evaluation of overall survival in 319 patients with resected PDAC. One LNR and one LODDS classification scheme were found to out-perform the N category in distinct patient subgroups. Only the LODDS classification exhibited statistically significant, gradually increasing HRs of their subcategories and, at the same time, significantly better discriminative potential in the subgroups of patients with PDAC of the head or corpus and in patients with tumor-free resection margins or M0 status, respectively.

Abstract

Background: Even though numerous novel lymph node (LN) classification schemes exist, an extensive comparison of their performance in patients with resected pancreatic ductal adenocarcinoma (PDAC) has not yet been performed. Method: We investigated the prognostic performance and discriminative ability of 25 different LN ratio (LNR) and 27 log odds of metastatic LN (LODDS) classifications by means of Cox regression and C-statistic in 319 patients with resected PDAC. Regression models were adjusted for age, sex, T category, grading, localization, presence of metastatic disease, positivity of resection margins, and neoadjuvant therapy. Results: Both LNR or LODDS as continuous variables were associated with advanced tumor stage, distant metastasis, positive resection margins, and PDAC of the head or corpus. Two distinct LN classifications, one LODDS and one LNR, were found to be superior to the N category in the complete patient collective. However, only the LODDS classification exhibited statistically significant, gradually increasing HRs of their subcategories and at the same time significantly higher discriminative potential in the subgroups of patients with PDAC of the head or corpus and in patients with tumor free resection margins or M0 status, respectively. On this basis, we built a clinically helpful nomogram to estimate the prognosis of patients after radically resected PDAC. Conclusion: One LNR and one LODDS classification scheme were found to out-perform the N category in terms of both prognostic performance and discriminative ability, in distinct patient subgroups, with reference to OS in patients with resected PDAC.

Systemic therapy in pancreatic ductal adenocarcinomas (PDACs)-basis and current status

A major shift in the approach to the management of pancreatic ductal adenocarcinomas (PDACs) has been the recognition of the systemic nature of the disease even in clinically and radiologically limited disease stages. The recalcitrant nature of PDAC is intrinsically related to the lack of therapeutic targets and dense surrounding stroma that limits the activity of currently available chemotherapeutic options. However, research is increasingly focusing on intensifying systemic management options in PDAC, resulting in gradual improvements in survival. Currently effective chemotherapeutic regimens like modified 5-fluorouracil-leucovorin-irinotecan-oxaliplatin and gemcitabine-nab-paclitaxel have improved outcomes in resectable and advanced PDAC. An increasing use of these regimens has also resulted in greater conversion of borderline resectable and locally advanced cancers to resection, though the most effective approach in this subgroup is yet to be identified. The current review presents an outline of the basic systemic nature of PDAC and current options of systemic therapy, predominantly chemotherapy .

Predictive Performance of Current Nodal Staging Systems in Various Categories of Pancreatic Cancer

BACKGROUND

Nodal staging systems (NSS) for pancreatic ductal adenocarcinoma (PDAC) classify patients on the basis of number of metastatic lymph nodes (MLN), metastatic/retrieved lymph node ratio (LNR), and log odds of positive LN (LODDS). The relative prognostic performance of these NSS, however, remains unclear.

PATIENTS AND METHODS

We identified 2584 patients who underwent surgery for PDAC between 2010 and 2019. Subgroups of each staging system were classified using K-adaptive partitioning method and assessed by comparing time-dependent areas under the curve (AUC) 5 years after surgery.

RESULTS

Patients were subgrouped by MLN (0, 1-3, ≥ 4), LNR (0, 0-0.23, > 0.23), and LODDS (< - 3.5, - 3.5 to - 0.970, > - 0.97). All three NSS were independent prognostic factors for overall survival (OS) and recurrence-free survival (RFS). The AUCs for OS were comparable for the MLN (0.622), LNR (0.609), and LODDS (0.596) systems. Subgroup evaluation based on 12 retrieved lymph nodes (RLN), R1 resection, and extent of resection showed that the AUCs of the MLN and LNR NSS were comparable for OS and RFS regardless of the number of RLNs, R1 resection, and extent of resection. By contrast, the AUCs of the LODDS NSS were lower.

CONCLUSION

The NSS based on the number of MLN is the best prognostic indicator, with prognostic performance comparable to the other NSS and greater convenience for practical use. This NSS was applicable regardless of the numbers of RLN, R1 resection, and extent of resection.

The role of coeliac axis resection in resected ductal adenocarcinoma of the distal pancreas: A result of tumour topography or a prognostic factor?

BACKGROUND

Whether coeliac axis resection (CAR) results from tumour topography or a prognostic factor for distal pancreatic ductal adenocarcinoma (PDAC) remains unclear. We aimed to compare the clinicopathological data between distal pancreatectomy with en bloc CAR (DP-CAR) and distal pancreatectomy plus splenectomy (DP-S) and analyse the prognostic factors.

METHODS

We retrospectively analysed clinicopathological data from 102 patients who underwent distal pancreatectomy for PDAC and the factors affecting disease-free survival (DFS) and overall survival (OS). Of these patients, 45 and 57 underwent DP-CAR and DP-S, respectively.

RESULTS

DP-CAR was associated with more operative challenges than DP-S: more portomesenteric vein resections (48.9% vs. 14.0%), longer operations (320 vs. 242 min), and greater estimated blood loss (EBL) (600 vs. 200 ml). DP-CAR had larger tumours (5 vs. 4 cm), more perineural invasion (91.1% vs. 73.7%), and more microscopically positive surgical margins (20% vs. 3.5%), compared to DP-S. The major complication was clinically relevant postoperative pancreatic fistula (20.6%). The median DFS was 15.8 months and the median OS was 20.1 months. CAR was not associated with DFS or OS. EBL>700 ml, lymphovascular invasion (LVI), and adjuvant chemotherapy independently affected DFS and OS.

CONCLUSION

DP-CAR was associated with larger tumours and more surgical challenges but not with poorer DFS and OS than DP-S. CAR was more likely to result from tumour topography rather than from an adverse prognostic factor for resected distal PDAC. EBL>700 ml, LVI, and adjuvant chemotherapy were independent factors affecting the survival of patients with distal PDAC who underwent surgical resection.

Rethinking the TNM Classification Regarding Direct Lymph Node Invasion in Pancreatic Ductal Adenocarcinoma

Simple Summary

Due to the rising burden of pancreatic cancer and poor outcomes, a precise, post-operative cancer staging for further and individualized therapy is needed. In the latest cancer classification system, the lymph node invasion mechanism is not addressed. Due to different outcomes regarding the lymph node invasion, we suggest a rethinking of the current system.

Abstract

Mechanisms of lymph node invasion seem to play a prognostic role in pancreatic ductal adenocarcinoma (PDAC) after resection. However, the 8th edition of the TNM classification of the American Joint Committee on Cancer (AJCC) does not consider this. The aim of this study was to analyse the prognostic role of different mechanisms of lymph node invasion on PDAC. One hundred and twenty-two patients with resected PDAC were examined. We distinguished three groups: direct (per continuitatem, Nc) from the main tumour, metastasis (Nm) without any contact to the main tumour, and a mixed mechanism (Ncm). Afterwards, the prognostic power of the different groups was analysed concerning overall survival (OS). In total, 20 patients displayed direct lymph node invasion (Nc = 16.4%), 44 were classed as Nm (36.1%), and 21 were classed as Ncm (17.2%). The difference in OS was not statistically significant between N0 (no lymph node metastasis, n = 37) and Nc (p = 0.134), while Nm had worse OS than N0 (p < 0.001). Direct invasion alone had no statistically significant effect on OS (p = 0.885). Redefining the N0 stage by including Nc patients showed a more precise OS prediction among N stages (p = 0.001 vs. p = 0.002). Nc was more similar to N0 than to Nm; hence, we suggest a rethinking of TNM classification based on the mechanisms of lymph node metastases in PDAC. Overall, this novel classification is more precise.

Analysis of safety and efficacy of laparoscopic distal pancreatectomy in the treatment of left pancreatic malignant tumors

OBJECTIVE

Distal pancreatectomy is the most extensive operation to treat malignant tumors of the left pancreas; however, malignant pancreatic tumors are prone to early invasion and metastasis.

METHODS

The clinical data of 80 patients undergoing surgical treatment for malignant tumors of the pancreatic body or tail from January 2013 to December 2017 were retrospectively analyzed. The main clinical variables were compared between patients undergoing laparoscopic distal pancreatectomy (LDP) vs. open distal pancreatectomy (ODP).

RESULTS

There were no significant differences in general patient characteristics, complications, and postoperative survival (χ² = 0.09) between the groups. The operation time in the LDP group was significantly longer than that in the ODP group; however, the LDP group was superior to the ODP group regarding the length of postoperative hospital stay, diet recovery, and rectal exhaust and ambulation times.

CONCLUSION

LDP is a safe and feasible treatment for left pancreatic malignancies, with the same surgical efficacy as ODP. LDP also has the advantages of minimally invasive surgery, such as minimal trauma and enhanced recovery after surgery.

Comparison of Characteristics and Survival Rates of Resectable Pancreatic Ductal Adenocarcinoma according to Tumor Location

The impact of tumor location on patient survival in pancreatic ductal adenocarcinoma (PDAC) remains controversial. This study investigated the association between primary tumor location and survival rates for resectable PDAC. Additionally, we assessed if this association remains consistent across categories of the Tumor-Node-Metastasis staging system. We analyzed 2471 patients who underwent surgical resection between 2000 and 2018 at a single center. Subgroup analysis was performed according to the Tumor-Node-Metastasis staging system. Among the group, 67.9% (1677 patients) had pancreatic head cancer (PHC) and 32.1% (794 patients) had pancreatic body/tail cancer (PBTC). Patients with PHC had worse overall survival and worse disease-free survival than those with PBTC. Patients with PHC had worse survival in stage IB and stage IIB than those with PBTC. No significant difference was observed for stages IA, IIA, and III. Multivariate analysis showed that elevated CA 19-9, mGPS, a longer hospital stay, complication, accompanying vein resection, larger tumor size, worse differentiation, higher TNM stage (stage IIB, III, IV), presence of LVI, and positive resection margin were risk factors for poor survival after resection. In resectable PDAC, patients with PHC had worse overall and disease-free survival than those with PBTC. However, tumor location was not an independent prognostic factor for PDAC.

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

BACKGROUND

Current treatment of potentially resectable pancreatic ductal adenocarcinoma (PDAC) includes pancreatic resection followed by adjuvant therapy. Aim of this study is to identify factors that are related with overall and early recurrence after pancreatectomy for PDAC.

METHODS

Retrospective analysis of patients with histologically confirmed PDAC who underwent pancreatectomy between September 2009 and December 2014. Early relapse was defined as recurrence within 12 months after surgery. Univariate/multivariate analysis was performed to identify prognostic factors for recurrence.

RESULTS

261 patients were included (54% males, mean age 67 years). Neoadjuvant and adjuvant treatments were performed in 55 (21%) and 243 (93%) patients. Overall morbidity was 56% with a rate of grade 3-4 Clavien-Dindo complications of 25%. Median disease-free survival was 18 months. Multivariate analysis identified nodal metastases (OR: 3.6) and perineural invasion (OR: 2.14) as independent predictors of disease recurrence in the entire cohort. 76 patients (29%) had an early recurrence. Poorly differentiated tumors (OR: 3.019) and grade 3-4 Clavien-Dindo complications (OR: 3.05) were independent risk factors for early recurrence.

CONCLUSION

Although overall recurrence is associated with tumor-related factors, severe postoperative complications represent an independent predictor of early recurrence. Patients at increased risk of severe postoperative complications may benefit from neoadjuvant therapy.

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.

Para-aortic lymph nodes and ductal adenocarcinoma of the pancreas: Distant neighbors?

BACKGROUND

Para-aortic lymph nodes in the ductal adenocarcinoma of the pancreatic head are regarded as distant metastases. Chemotherapy is considered the only treatment option if para-aortic lymph nodes metastases are detected preoperatively or intraoperatively. The role of standardized para-aortic lymph node lymphadenectomy during pancreaticoduodenectomy remains controversial. The aim of this study was to evaluate complication profiles and survival.

METHODS

All cases of ductal adenocarcinoma of the pancreatic head were evaluated from a prospectively maintained database (n = 289). Para-aortic lymph node lymphadenectomy was routinely performed in all patients with suspected ductal adenocarcinoma of the pancreatic head. Subgroup analysis was performed between patients with histologically positive (+) and negative (-) para-aortic lymph nodes. Patients receiving pancreaticoduodenectomy without para-aortic lymph node lymphadenectomy for other causes served as a control group.

RESULTS

A total of 192 patients received para-aortic lymph node lymphadenectomy, of which 41 were positive for para-aortic lymph node metastases. In 97 patients with ductal adenocarcinoma of the pancreatic head, no para-aortic lymph node lymphadenectomy was performed owing to postoperative pancreatic ductal adenocarcinoma diagnosis. Clinicopathologic data were homogenously distributed. Hospital stay and postoperative morbidity demonstrated no significant difference between the 3 subgroups. The median overall survival of 19.63 months (95% confidence interval: 14.57-24.79 months) in para-aortic lymph node- patients was not statistically different when compared with the median overall survival of 18.22 months (95% confidence interval: 12.68-23.75 months) in para-aortic lymph node + patients (log-rank test P = .223). Preoperative computed tomography was a poor predictor for para-aortic lymph node status (sensitivity = 10.3%, specificity = 97.8%).

CONCLUSION

This study represents the largest cohort receiving routine para-aortic lymph node lymphadenectomy. Extended lymphadenectomy can be performed safely and, although disease-free survival of para-aortic lymph node+ patients was significantly shorter, overall survival and postrelapse survival were on par with that of para-aortic lymph node- patients. Preoperative computed tomography indicating para-aortic lymph node metastasis should not preclude curative resection.

Does direct invasion of peripancreatic lymph nodes impact survival in patients with pancreatic ductal adenocarcinoma? A retrospective dual-center study

BACKGROUND

Pancreatic ductal adenocarcinoma can directly invade the peripancreatic lymph nodes; however, the significance of direct lymph node invasion is controversial, and it is currently classified as lymph node metastasis. This study aimed to identify the impact of direct invasion of peripancreatic lymph nodes on survival in patients with pancreatic ductal adenocarcinoma.

METHODS

A total of 411 patients with resectable/borderline resectable pancreatic ductal adenocarcinoma who underwent pancreatic resection at two high-volume centers from 2006 to 2016 were evaluated retrospectively.

RESULTS

Sixty (14.6%) patients had direct invasion of the peripancreatic lymph nodes without isolated lymph node metastasis (N-direct group), 189 (46.0%) had isolated lymph node metastasis (N-met group), and 162 (39.4%) had neither direct invasion nor isolated metastasis (N0 group). There was no significant difference in median overall survival between the N-direct group (35.0 months) and the N0 group (45.6 month) (p = 0.409), but survival was significantly longer in the N-direct compared with the N-met group (25.0 months) (p = 0.003). Similarly, median disease-free survival was similar in the N-direct (21.0 months) and N0 groups (22.7 months) (p = 0.151), but was significantly longer in the N-direct compared with the N-met group (14.0 months) (p < 0.001). Multivariate analysis identified resectability, adjuvant chemotherapy, and isolated lymph node metastasis as independent predictors of overall survival. However, direct lymph node invasion was not a predictor of survival.

CONCLUSION

Direct invasion of the peripancreatic lymph nodes had no effect on survival in patients undergoing pancreatic resection for pancreatic ductal adenocarcinoma, and should therefore not be classified as lymph node metastasis.

Lymph Node Metastatic Patterns and Survival Predictors Based on Tumor Size in Pancreatic Ductal Adenocarcinoma

INTRODUCTION

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies. Larger tumor size is widely acknowledged to be associated with increased lymph node (LN) metastatic potential. However, the quantitative relationships between tumor size and LN metastasis or survival remain unclear. This study aims to quantify the objective relationship between tumor size and the prevalence of LN metastases across a spectrum primary tumor size.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was used to identify 9958 patients with resected PDAC without distant metastasis. The prevalence of LN metastases, LN ratio (LNR), and N2/N1 ratio were assessed amongst different tumor sizes, and the relationships were displayed by matched curves.

RESULTS

In the enrolled cohort, age, tumor site, grade, American Joint Committee on Cancer (AJCC) 8th node staging, tumor size, chemotherapy, and radiotherapy were identified as significant independent predictors for overall survival (OS) and cancer-specific survival (CSS). For tumors within 1-40 mm in size, the prevalence of node-positive disease is closely modelled using a logarithmic formula [0.249 × ln (size) + 0.452] × 100%. The prevalence plateaued between 70% and 80% beyond 40 mm. The mean LNR increased in a stepwise manner as tumor size increased from 1-5 mm (LNR = 0.024) to 41-45 mm (LNR = 0.177); then, beyond 45 mm, it plateaued near 0.170. N2/N1 ratio gradually increased along with tumor size from 1-5 mm (N2/N1 = 0.286) to 41-45 mm (N2/N1 = 1.016), and when tumor size reached to 41-45 mm or more, the ratio stabilized around 1.000. In addition, significant survival prediction by AJCC N staging was observed when tumors ranging between 16 and 45 mm in size.

CONCLUSION

Regional LN involvement demonstrated a logarithmic growth with increasing tumor sizes in patients with resected PDAC . The probability of metastasis in each regional LN for resected PDAC with tumors greater than 40 mm in size was near 17.0% and their overall prevalence of LN metastasis was 70-80%. Among which, 50% of patients had an N2 stage. Such prediction may be a potential and promising tool for guiding lymphadenectomy in PDAC surgery.

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.

A Novel Nomogram Based on Log Odds of Metastatic Lymph Nodes to Predict Overall Survival in Patients With Perihilar Cholangiocarcinoma After Surgery

Background

Various lymph node staging strategies were reported to be significantly correlated with perihilar cholangiocarcinoma(pCCA) prognosis. This study aimed to evaluate their predictive abilities and construct an optimal model predicting overall survival (OS).

Methods

Patients with pCCA were collected as the training cohort from the Surveillance, Epidemiology, and End Results (SEER) database. Four models were constructed, involving four LNs staging strategies. The optimal model for predicting OS was evaluated by calculation of the concordance index (C-index) and Akaike information criterion (AIC), and validated by using the area under curve (AUC) and calibration curves. The clinical benefits of nomogram were evaluated by decision curve analysis (DCA). A Chinese cohort was collected to be an external validation cohort.

Results

There were 319 patients and 109 patients in the SEER database and Chinese cohort respectively. We developed an optimal model involving age, T stage, tumor size, LODDS, which showed better predictive accuracy than others. The C-index of the nomogram was 0.695, the time-dependent AUC exceeded 0.7 within 36 months which was significantly higher than that of the American Joint Committee on Cancer (AJCC) stage. The calibration curves for survival probability showed the nomogram prediction had good uniformity of the practical survival. The DCA curves exhibited our nomogram with higher clinical utility compared with the AJCC stage and single LOODS.

Conclusions

LODDS is a strong independent prognostic factor, and the nomogram has a great ability to predict OS, which helps assist clinicians to conduct personalized clinical practice.

Long-Term Survivors after Upfront Resection for Pancreatic Ductal Adenocarcinoma: An Actual 5-Year Analysis of Disease-Specific and Post-Recurrence Survival

BACKGROUND

Data on long-term actual survival in patients with surgically resected pancreatic ductal adenocarcinoma (PDAC) are limited. The aim of this study was to evaluate the actual 5-year disease-specific survival (DSS) and post-recurrence survival (PRS) in patients who underwent pancreatectomy for PDAC.

METHODS

Data from patients who underwent upfront surgical resection for PDAC between 2009 and 2014 were analyzed. Exclusion criteria included PDAC arising in the background of an intraductal papillary mucinous neoplasm and patients undergoing neoadjuvant therapy. All alive patients had a minimum follow-up of 60 months. Independent predictors of PRS, DSS, and survival > 5 years were searched.

RESULTS

Of the 176 patients included in this study, 48 (27%) were alive at 5 years, but only 20 (11%) had no recurrence. Median PRS was 12 months. In the 154 patients after disease recurrence, independent predictors of shorter PRS were total pancreatectomy, G3 tumors, early recurrence (< 12 months from surgery), and no treatment at recurrence. Median DSS was 36 months. Independent predictors of DSS were CA19-9 at diagnosis > 200 U/mL, total pancreatectomy, N + status, G3 tumors and perineural invasion. Only the absence of perineural invasion was a favorable independent predictor of survival > 5 years.

CONCLUSION

More than one-quarter of patients who underwent upfront surgery for PDAC were alive after 5 years, although only 11% of the initial cohort were cancer-free. Long-term survival can also be achieved in tumors with more favorable biology in an upfront setting followed by adjuvant chemotherapy.

Original study: The rescue staging for pancreatic ductal adenocarcinoma with inadequate examined lymph nodes

BACKGROUND

In previous studies, it's recommended that the lymph node involvement should be evaluated with enough examined lymph nodes (eLNs) in the 8th American Joint Committee on Cancer (AJCC) staging system for pancreatic cancer. This study aims to put forward a rescue staging system for pancreatic ductal adenocarcinoma (PDAC) patients with inadequate eLNs after pancreatoduodenectomy (PD).

METHOD

11,224 PDAC patients undergoing PD in The Surveillance, Epidemiology, and End Results (SEER) database were included. Another Ruijin Pancreatic Disease Center (RJPDC) database consisted of 821 patients was utilized for external validation.

RESULTS

The proportions of patients with eLNs≥15 were 44.7% and 32.8% in SEER and RJPDC database separately. The rescue staging system was put forward relying on LNR (HR = 1.83, 95% CI 1.74-1.92, P < 0.001) for N staging of eLNs<15 population and pLNs for the rest. The TNM modalities were also rearranged in the rescue system for better survival coordination. The C-index of rescue staging system was 0.638 while that of AJCC 8th staging system was 0.613 in SEER database. Similar phenomena were observed in RJPDC database. Kaplan-Meier analyses revealed reliable internal coherences (SEER: Ib: P = 0.26; IIa: P = 0.063; IIb: P = 0.53; IIIa: P = 0.11.

RJPDC

Ib: P = 0.32; IIa: P = 0.66; IIb: P = 0.76; IIIa: P = 0.66) and significant staging efficiency (SEER: P < 0.001; RJPDC: P = 0.002).

CONCLUSION

A rescue staging system was put forward regardless of the eLNs number. And the novel system manifested better predictive capacity than 8th AJCC staging system.

Nomogram and competing risk model to predict recurrence after curative surgical resection of PDAC

BACKGROUND

Surgical resection remains the only potentially curative treatment for pancreatic ductal adenocarcinoma (PDAC). However, a number of patients get disease recurred in a short time post-operation. Few studies have focused on the predictors of different recurrence patterns of PDAC.

OBJECTIVE

To try to establish and verify a nomogram to predict recurrence free survival (RFS) in PDAC patients, and to distinguish the risk factors of local recurrence first and distant metastasis first via competing risk model.

METHODS

Patients who underwent radical pancreatectomy for PDAC in our center from 2010 to 2018 were reviewed retrospectively. Kaplan-Meier methods and multivariate Cox regression analyses were used to identify the clinicopathological predictors of recurrence post-operation. And then, a nomogram was constructed and validated. Competing risk regression model was used to compare the predictors between local recurrence group and distant metastasis group.

RESULTS

A total of 200 patients were included into the final analysis, and 153 patients got disease relapsed post-operation. CA19-9 level, vascular resection, tumor differentiation, lymph node ratio (LNR) and adjuvant chemotherapy were identified as independent risk factors for recurrence free survival (RFS) and incorporated into the nomogram. The C-index of the nomogram was 0.650. Competing risk model indicated that the status of lymph-node metastasis was significantly associated the patterns of first relapse.

CONCLUSIONS

Nomogram and competing risk model were constructed to quantify the risk of recurrence following surgery for PDAC. Our findings may be useful for predicting RFS and recurrence pattern in clinical work.

Radical antegrade modular pancreatosplenectomy (RAMPS) versus conventional distal pancreatectomy for left-sided pancreatic cancer: findings of a multicenter, retrospective, propensity score matching study

PURPOSE

Radical antegrade modular pancreatosplenectomy (RAMPS) has been reported to achieve high rates of a negative margin and resected metastatic lymph nodes. However, many studies have used historical controls and the results remain controversial. We conducted this study to compare the surgical and long-term outcomes of RAMPS vs. conventional distal pancreatectomy (DP).

METHODS

The subjects of this multicenter retrospective study were 106 patients who underwent curative resection for left-sided pancreatic cancer between 2012 and 2017. Overall survival (OS) and recurrence-free survival (RFS) rates were compared using Kaplan-Meier estimates.

RESULTS

The RAMPS group had more advanced T (T3/T4) and N stages (N1/N2) and a larger tumor size than the conventional group (T stage, p = 0.04; N stage, p = 0.02; tumor size, p = 0.04). The RAMPS group had more harvested metastatic lymph nodes (p = 0.02). After propensity-score matching, 37 patients from each group were included in the final analysis. There was no significant difference in RFS (p = 0.463) or OS (p = 0.383) between the groups. Multivariate analyses revealed the completion of chemotherapy to be an independent factor for RFS and OS (both p < 0.001).

CONCLUSIONS

There was no difference in the RFS or OS between RAMPS and conventional DP in this series. RAMPS may be an option for R0 resection of advanced tumors; however, postoperative chemotherapy has a greater influence than the surgical procedure on the prognosis of patients with pancreatic cancer.

Defining a minimum number of examined lymph nodes improves the prognostic value of lymphadenectomy in pancreas ductal adenocarcinoma

BACKGROUND

Lymph node (LN) metastasis is associated with decreased survival following resection for pancreatic ductal adenocarcinoma (PDAC). In N0 disease, increasing total evaluated LN (ELN) correlates with improved outcomes suggesting patients may be understaged when LNs are undersampled. We aim to assess the optimal number of examined lymph nodes (ELN) following pancreatectomy.

METHODS

Data from 1837 patients undergoing surgery were prospectively collected. The binomial probability law was utilized to analyze the minimum number of examined LNs (minELN) and accurately characterize each histopathologic stage. LN ratio (LNR) was compared to American Joint Committee on Cancer (AJCC) guidelines.

RESULTS

As ELN total increased, the likelihood of finding node positive disease increased. An evaluation based upon the binomial probability law suggested an optimal minELN of 12 for accurate AJCC N staging. As the number of ELNs increased, the discriminatory capacity of alternative strategies to characterize LN disease exceeded that offered by AJCC N stage.

CONCLUSION

This is the first study dedicated to optimizing histopathologic staging in PDAC using models of minELN informed by the binomial probability law. This study highlights two separate cutoffs for ELNs depending upon prognostic goal and validates that 12 LNs are adequate to determine AJCC N stage for the majority of patients.