Impact of total lymph node count and lymph node ratio on staging and survival after pancreatectomy for pancreatic adenocarcinoma: a large, population-based analysis

The preoperative prediction of lymph node metastasis of resectable pancreatic ductal adenocarcinoma using dual-layer spectral computed tomography

OBJECTIVES

To investigate the value of dual-layer spectral computed tomography (DLCT) parameters derived from primary tumors in predicting lymph node metastasis (LNM) of resectable pancreatic ductal adenocarcinoma (PDAC).

MATERIALS AND METHODS

In this retrospective study, patients with resectable PDAC who underwent DLCT within 2-week intervals before surgery were enrolled and randomly divided into training and validation sets at a 7:3 ratio. The patients' clinical data, CT morphological features, and DLCT parameters were analyzed. Univariate and multivariate logistic analyses were used to identify the predictors and construct a predictive model, and receiver operator characteristic (ROC) curves were programmed to evaluate the predictive efficacy.

RESULTS

We enrolled 107 patients (44 patients with LNM and 63 patients without LNM). Among all variables, iodine concentration in the venous phase, extracellular volume, and tumor size were identified as independent predictors of LNM. The nomogram model, incorporating the two DLCT parameters and the morphological feature, achieved an area under the curve (AUC) of 0.877 (95% confidence interval [CI]: 0.803-0.952) and 0.842 (95% CI: 0.707-0.977) for predicting LNM in the training and validation sets, respectively. Furthermore, the AUC of the nomogram model was greater than that of morphological features of lymph nodes in the training (AUC = 0.877 vs. 0.570) and validation (AUC = 0.842 vs. 0.583) sets.

CONCLUSIONS

DLCT has the potential to predict LNM in patients with resectable PDAC and show a better predictive value than morphological features of lymph nodes.

KEY POINTS

Question Morphological features of lymph nodes are of limited value in detecting metastatic lymph nodes in pancreatic ductal adenocarcinoma (PDAC). Findings Dual-layer spectral computed tomography (DLCT) parameters and morphological features derived from PDAC lesions show good preoperatively predictive efficacy for lymph node metastasis. Clinical relevance The proposed DLCT-based nomogram model may serve as an effective and convenient tool for preoperatively predicting lymph node metastasis of resectable PDAC.

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.

Prognostic significance of three lymph node staging systems in pancreatic cancer with ≤ 12 and > 12 retrieved lymph nodes

This study aimed to evaluate and compare the predictive performance of negative lymph nodes (NLN), lymph node ratio (LNR), and N stage in pancreatic ductal adenocarcinoma (PDAC) among patients with ≤ 12 retrieved lymph nodes and those with > 12 retrieved lymph nodes. Moreover, the association between the three nodal staging systems and survival was also explored. Clinical data on patients diagnosed with PDAC between 2004 and 2020 were downloaded from the Surveillance, Epidemiology, and End Results (SEER) database. Cox regression was performed to identify independent predictors of cancer specific survival (CSS) and overall survival (OS). Survival probability was calculated and compared by the Kaplan-Meier method and log rank test. Akaike information criterion (AIC) and Harrell's C-index were used to evaluate the prognostic ability of each nodal staging system. All three lymph node staging systems were independent predictors of CSS and OS. A higher NLN, a lower N stage, and a lower LNR were associated with improved survival. Compared with N stage, LNR staging performed better with a lower AIC and higher C-index for predicting the prognosis regardless of the sufficiency of retrieved lymph nodes, while NLN staging performed poorly in both the training and validation set. Subgroup analyses showed that the NLN successfully predicted survival outcomes in both lymph node-positive and node-negative patients. LNR demonstrated better predictive performance in PDAC patients regardless of the sufficiency of retrieved lymph nodes. Notably, for stage N0 disease, NLN was a more important prognostic predictor. The combination of LNR and NLN may offer more precise information on lymph node staging than the current staging system.

Ferumoxtran-10-enhanced MRI for pre-operative metastatic lymph node detection in pancreatic, duodenal, or periampullary adenocarcinoma

OBJECTIVES

To assess 3-Tesla (3-T) ultra-small superparamagnetic iron oxide (USPIO)-enhanced MRI in detecting lymph node (LN) metastases for resectable adenocarcinomas of the pancreas, duodenum, or periampullary region in a node-to-node validation against histopathology.

METHODS

Twenty-seven consecutive patients with a resectable pancreatic, duodenal, or periampullary adenocarcinoma were enrolled in this prospective single expert centre study. Ferumoxtran-10-enhanced 3-T MRI was performed pre-surgery. LNs found on MRI were scored for suspicion of metastasis by two expert radiologists using a dedicated scoring system. Node-to-node matching from in vivo MRI to histopathology was performed using a post-operative ex vivo 7-T MRI of the resection specimen. Sensitivity and specificity were calculated using crosstabs.

RESULTS

Eighteen out of 27 patients (median age 65 years, 11 men) were included in the final analysis (pre-surgery withdrawal n = 4, not resected because of unexpected metastases peroperatively n = 2, and excluded because of inadequate contrast-agent uptake n = 3). On MRI 453 LNs with a median size of 4.0 mm were detected, of which 58 (13%) were classified as suspicious. At histopathology 385 LNs with a median size of 5.0 mm were found, of which 45 (12%) were metastatic. For 55 LNs node-to-node matching was possible. Analysis of these 55 matched LNs, resulted in a sensitivity and specificity of 83% (95% CI: 36-100%) and 92% (95% CI: 80-98%), respectively.

CONCLUSION

USPIO-enhanced MRI is a promising technique to preoperatively detect and localise LN metastases in patients with pancreatic, duodenal, or periampullary adenocarcinoma.

CLINICAL RELEVANCE STATEMENT

Detection of (distant) LN metastases with USPIO-enhanced MRI could be used to determine a personalised treatment strategy that could involve neoadjuvant or palliative chemotherapy, guided resection of distant LNs, or targeted radiotherapy.

REGISTRATION

The study was registered on clinicaltrials.gov NCT04311047. https://clinicaltrials.gov/ct2/show/NCT04311047?term=lymph+node&cond=Pancreatic+Cancer&cntry=NL&draw=2&rank=1 .

KEY POINTS

LN metastases of pancreatic, duodenal, or periampullary adenocarcinoma cannot be reliably detected with current imaging. This technique detected LN metastases with a sensitivity and specificity of 83% and 92%, respectively. MRI with ferumoxtran-10 is a promising technique to improve preoperative staging in these cancers.

Comparing oncologic and surgical outcomes of robotic and laparoscopic distal pancreatectomy: a propensity-matched analysis

BACKGROUND

The frequency of minimally invasive distal pancreatectomy is gradually exceeding that of the open approach. Our study aims to compare short-term outcomes of robotic (RDP) and laparoscopic (LDP) distal pancreatectomies for pancreatic ductal adenocarcinoma (PDAC) using a national database.

METHODS

The National Cancer Database was utilized to identify patients with PDAC who underwent distal pancreatectomy from 2010-2020. Short-term technical and oncologic outcomes such as margin status and nodal harvest were included. Propensity-score matching (PSM) was performed comparing LDP and RDP cohorts. Multivariate logistic-regression models were then used to assess the impact of institutional volume on the MIDP surgical and technical oncologic outcomes.

RESULTS

1537 patients underwent MIDP with curative intent. Most cases were laparoscopic (74.4%, n = 1144), with a gradual increase in robotic utilization, from 8.7% in 2010 to 32.0% of MIDP cases ten years later. For PSM, 698 LDP patients were matched with 349 RDP. The odds of conversion to an open case were 58% less in RDP (12.6%) compared to LDP (25.5%) with no statistically significant difference in technical oncologic results. There was no difference in length of stay (OR = 1.0[0.7-1.4]), 30-day mortality (OR = 0.5[0.2-2.0]) or 90-day mortality (OR = 1.1[0.5-2.4]) between RDP and LDP, although there was a higher 30-day readmission rate with RDP (OR = 1.71[1.1-2.7]). There were statistically significant differences in technical oncologic outcomes (nodal harvest, margin status, initiation of adjuvant therapy) based on MIDP volume quartiles.

CONCLUSION

Laparoscopic and robotic distal pancreatectomy have similar peri- and post-operative surgical and oncologic outcomes, with a higher rate of conversion to open in the laparoscopic cohort.

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.

Influence of sarcopenia on postoperative complications and long-term survival in pancreatic cancer patients undergone pancreaticoduodenectomy

BACKGROUND

Sarcopenia has the potential to impact the postoperative results and extended prognosis of various types of tumors. Nevertheless, the specific impact of sarcopenia on the postoperative results and long-term survival of pancreatic cancer (PC) following pancreaticoduodenectomy (PD) remains inadequately elucidated. This study investigates the significance of sarcopenia according to various Asian standards on postoperative complications and long-term prognosis in PC patients who have undergone PD.

METHODS

This retrospective study systematically analyzed patients with PC who underwent PD from January 2015 to December 2022. Sarcopenia was diagnosed by the skeletal muscle index (SMI) obtained by the skeletal muscle area normalized for height squared on the third lumbar vertebra on computed tomography (CT) images. Univariate and multivariate logistic regression analysis were performed to analyze the correlation between sarcopenia and postoperative complications, while Cox regression analysis was utilized to explore the influence of sarcopenia on overall survival (OS) and recurrence-free survival (RFS) in PC patients after PD.

RESULTS

We enrolled 162 patients with PC after PD (92 males and 70 females, mean age: 63.78 ± 10.27 years), including 83 and 79 patients with sarcopenia and non-sarcopenia, respectively. Compared with non-sarcopenia patients, sarcopenia exhibited higher rates of recurrence rate (75% versus 59%, p = 0.039). Univariate and multivariate logistic regression analysis showed that sarcopenia did not affect the incidence of complications in patients with PC after PD in three Asian sarcopenia criteria. Multivariate Cox regression analysis indicated that sarcopenia was an independent risk factor for OS (hazard ratio [HR]: 2.49, 95% confidence interval [CI]: 1.73-3.60, p < 0.001) and RFS(hazard ratio [HR]: 1.70, 95%confidence interval [CI]: 1.12-2.50, p = 0.012) of PC patients with PD in Japanese Society of Hepatology criteria. Meanwhile, according to the Asian pancreatic cancer population standard, sarcopenia is an independent risk factor affecting the long-term OS (hazard ratio [HR]: 2.59, 95% confidence interval [CI]: 1.80-3.70, p < 0.001) and RFS (hazard ratio [HR]: 2.00, 95% confidence interval [CI]: 1.36-3.00, p < 0.001) of PC after PD. While sarcopenia is recognized as a risk factor for OS (hazard ratio [HR]: 1.81, 95% confidence interval [CI]: 1.08-3.10, p = 0.025) in PC patients based on the Fujiwara criteria, it is not found to be associated with RFS (hazard ratio [HR]: 1.60, 95% confidence interval [CI]: 0.90-3.00, p = 0.10). The model based on sarcopenia and clinical characteristics has high predictive ability for OS and RFS.

CONCLUSION

Various Asian diagnostic criteria do not link sarcopenia with postoperative complications in PC patients after PD. Nevertheless, sarcopenia remains a significant independent risk factor for long-term survival, and its combination with clinical characteristics can aid clinicians in predicting long-term survival outcomes.

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.

Lymph Node Ratio as a Predictive Factor of Persistent/Recurrent Disease in Patients With Medullary Thyroid Cancer: A Single-Center Retrospective Study

OBJECTIVE

Thyroidectomy with neck lymph node dissection is curative for most patients with medullary thyroid cancer (MTC). Lymph node ratio (LNR, ie, the ratio between the metastatic and the removed lymph nodes) is a reliable parameter with which to estimate both disease extent and quality of neck dissection. The aim of this study was to investigate the prognostic role of LNR to predict persistent/recurrent disease in patients with MTC.

METHODS

A single-center, retrospective study of a consecutive cohort of 95 patients with MTC treated with total thyroidectomy and neck dissection. Receiver operating characteristics curve analysis was performed to identify the LNR cut-off.

RESULTS

LNR was positively associated with tumor size, preoperative and postoperative calcitonin values, postsurgery carcinoembryonic antigen values, persistent/recurrent disease, and the occurrence of distant metastases during follow-up. At multivariate analysis, persistent/recurrent disease was independently associated with the LNR value and was accurately predicted by a cut-off value of 0.12 (area under the curve = 0.85). Indeed, patients with LNR ≥0.12 had a higher probability of developing persistent/recurrent disease (79.3% vs 10.6%, odds ratio = 32.3, 95% CI = 9.8-106.4; P < .001) and distant metastasis (34.5% vs 3.0%, odds ratio = 16.8, 95% CI = 3.4-83.6; P < .001) than patients with LNR <0.12. The median time to progression was 15 months in patients with LNR ≥0.12 whereas it was not reached in patients with LNR <0.12 (hazard ratio: 7.18, 95% CI = 3.01-17.11, P < .001).

CONCLUSIONS

LNR is a reliable prognostic factor to predict the risk of recurrence, persistence, and distant metastases in patients with MTC.

Association between preoperative sarcopenia and prognosis of pancreatic cancer after curative-intent surgery: a updated systematic review and meta-analysis

BACKGROUND

Sarcopenia is associated with poor outcomes in many malignancies. However, the relationship between sarcopenia and the prognosis of pancreatic cancer has not been well understood. The aim of this meta-analysis was to identify the prognostic value of preoperative sarcopenia in patients with pancreatic cancer after curative-intent surgery.

METHODS

Database from PubMed, Embase, and Web of Science were searched from its inception to July 2023. The primary outcomes were overall survival (OS), progression-free survival (PFS), and the incidence of major complications. The hazard ratio (HR), odds ratio (OR), and 95% confidence intervals (CIs) were used to assess the relationship between preoperative sarcopenia and the prognosis of patients with pancreatic cancer. All statistical analyses were conducted by Review Manager 5.3 and STATA 17.0 software.

RESULTS

A total of 23 retrospective studies involving 5888 patients were included in this meta-analysis. The pooled results demonstrated that sarcopenia was significantly associated with worse OS (HR = 1.53, P < 0.00001) and PFS (HR = 1.55, P < 0.00001). However, this association was not obvious in regard to the incidence of major complications (OR = 1.33, P = 0.11).

CONCLUSION

Preoperative sarcopenia was preliminarily proved to be associated with the terrible prognosis of pancreatic cancer after surgery. However, this relationship needs to be further validated in more prospective studies.

Lymph node examination and survival in resected pancreatic ductal adenocarcinoma: retrospective study

BACKGROUND

The minimum number of examined lymph nodes (ELN) required for adequate staging and best prediction of survival has not been established in pancreatic ductal adenocarcinoma (PDAC). The aim of the study was to investigate the influence of ELN on staging and survival in PDAC.

METHODS

Patients undergoing partial or total pancreatectomy for PDAC at two European university hospitals between 2007 and 2018 were retrospectively reviewed. Multivariate Cox regression model and survival analyses were performed to verify adequate staging.

RESULTS

Overall 341 (73 per cent) patients showed lymph node metastasis (N1/N2), whereas 125 (27 per cent) patients had no lymph node involvement (N0). With increasing number of ELN, the proportion of positive lymph nodes increased. The minimum number of ELN needed to detect lymph node involvement was 21. In multivariate analysis, examination of <21 lymph nodes was a significant negative predictor for survival. Examination of ≥21 ELN reversed this effect and ruled out possible misclassification.

CONCLUSION

The number of ELN affects survival in PDAC. Possible misclassification was identified when <21 lymph nodes were examined. Therefore, at least 21 lymph nodes must be examined to avoid false lymph node classification in all types of resection.

Progress in the application of dual-energy CT in pancreatic diseases

Pancreatic diseases are difficult to diagnose due to their insidious onset and complex pathophysiological developmental characteristics. In recent years, dual-energy computed tomography (DECT) imaging technology has rapidly advanced. DECT can quantitatively extract and analyze medical imaging features and establish a correlation between these features and clinical results. This feature enables the adoption of more modern and accurate clinical diagnosis and treatment strategies for patients with pancreatic diseases so as to achieve the goal of non-invasive, low-cost, and personalized treatment. The purpose of this review is to elaborate on the application of DECT for the diagnosis, biological characterization, and prediction of the survival of patients with pancreatic diseases (including pancreatitis, pancreatic cancer, pancreatic cystic tumor, pancreatic neuroendocrine tumor, and pancreatic injury) and to summarize its current limitations and future research prospects.

Proposal for a new N-stage classification system for intrahepatic cholangiocarcinoma

Background

The number of metastatic lymph nodes (MLNs) is not considered in the nodal status (N classification) of intrahepatic cholangiocarcinoma (ICC) in the current 8thEdition of the American Joint Committee on Cancer (AJCC) staging system. The aim of this study was to find out the optimal cut-off point based on the number of MLNs and establish a modified AJCC staging system for ICC according to the new N category.

Methods

A total of 675 ICC patients diagnosed between 2004 and 2015 were retrieved from the Surveillance, Epidemiology and End Results (SEER) database. The optimal cut-off value of MLNs affecting survival was determined by X-tile software. The relative discriminative power was assessed by Harrell's concordance index (C-index) and Akaike information criterion (AIC).

Results

The proposed new nodal category subdivided patients into three groups (N0, no MLN; N1, 1-3 MLNs; and N2, ≥ 4 MLNs) with significantly different overall survival (P < 0.001). Multivariable analysis revealed that the new nodal category was an independent prognostic factor (P < 0.001). Both the C-index and AIC for our modified staging system were better than those for the 8th AJCC edition (0.574 [95% confidence interval 0.533-0.615] versus 0.570 [95% confidence interval 0.527-0.613], and 853.30 versus 854.21, respectively).

Conclusion

The modified AJCC staging system based on the number of MLNs may prove to be a useful alternative for predicting survival of ICC patients in clinical practice.

The differential effects of sarcopenia and cachexia on overall survival for pancreatic ductal adenocarcinoma patients following pancreatectomy: A retrospective study based on a large population

OBJECTIVES

Both cachexia and sarcopenia have been considered adverse predictors for prognosis in patients with pancreatic cancer; although sarcopenia and cachexia share some similarities, they are still defined as distinct nutritional conditions. We aimed to explore the differential impacts of sarcopenia and cachexia on prognosis for pancreatic ductal adenocarcinoma (PDAC) patients following radical excision.

METHODS

From January 2015 to May 2022, 614 patients undergoing surgery for PDAC were retrospectively included. Sarcopenia was defined as the L3 total skeletal muscle index below 52.4 cm2 /m2 (men) and 38.5 cm2 /m2 (women). Cachexia was classified according to the following criteria: involuntary weight loss >5% over the past 6 months, or weight loss >2% and BMI <20 kg/m2 , or weight loss >2% and sarcopenia.

RESULTS

Of the 614 patients included in the analysis, 62% and 48% were diagnosed with sarcopenia and cachexia, respectively. Kaplan-Meier analysis showed that sarcopenia and/or cachexia were significantly associated with worse overall survival (OS) rather than worse recurrence-free survival (RFS). Moreover, Cox regression analysis revealed that cachexia rather than sarcopenia was an adverse factor for OS in all PDAC patients. For poorly differentiated PDAC, both cachexia and sarcopenia were significantly associated with shorter OS. However, for moderately/well-differentiated PADC, cachexia was an independent factor for adverse OS, but not sarcopenia.

CONCLUSIONS

Sarcopenia and cachexia have different effects on OS for PDAC patients undergoing radical excision. This difference may provide some important information for preoperative management.

Lymph node assessment technique matters in radical cystectomy for bladder cancer

BACKGROUND

For patients undergoing radical cystectomy with pelvic lymph node dissection for urothelial cancer, a lymph node count of at least 16 is associated with improved cancer-specific and overall survival. Lymph node yield is presumed to relate directly to extent of dissection and surgical quality, however limited studies have reviewed the impact of the pathological assessment process of lymph nodes on lymph node yield.

METHOD

A retrospective assessment of 139 patients who had radical cystectomy for urothelial cancer between March 2015 and July 2021 from Fiona Stanley Hospital (Perth, Australia) by a single surgeon was assessed. A change in pathological assessment process from assessment of only palpable lymph nodes to microscopic assessment of the entire submitted specimens occurred in August 2018. Patients were divided into two groups accordingly and other relevant demographic and pathological data was recorded. The impact of pathological processing technique on lymph node yield was assessed using the Student T test and logistical regression was used to assess the impact of other demographic variables.

RESULTS

The mean lymph node yield was 16.2 nodes (IQR 12-23) in 54 patients in the pre-process change group compared to 22.4 nodes (IQR 15-28.4) in 85 patients in the post-process change group (P < 0.0001). 53.7% had 16 or more nodes in the pre-process change group compared to 71.3% in the post-process change group (P = 0.04). Age, BMI, and gender were not significant predictors of lymph node yield.

CONCLUSION

The current study demonstrates that the microscopic assessment of all lymph node tissue detects significantly more lymph nodes than only examining palpably abnormal tissue. Pathologic assessment protocols should be standardized to this technique to ensure the utility of lymph node yield as a quality metric.

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.

International assessment and validation of the prognostic role of lymph node ratio in patients with resected pancreatic head ductal adenocarcinoma

Background

Lymph node ratio (LNR; positive/harvested lymph nodes) was identified as overall survival predictor in several cancers, including pancreatic adenocarcinoma. It remains unclear if LNR is predictive of overall survival in pancreatic adenocarcinoma patients staged pN2. This study assessed the prognostic overall survival role of LNR in pancreatic adenocarcinoma patients in relation with lymph node involvement.

Methods

A retrospective international study in six different centers (Europe and United States) was performed. Pancreatic adenocarcinoma patients who underwent pancreatoduodenectomy from 2000 to 2017 were included. Patients with neoadjuvant treatment, metastases, R2 resections, or missing data regarding nodal status were excluded. Survival curves were calculated using Kaplan-Meier method and compared using log-rank test. Multivariable Cox regressions were performed to find independent overall survival predictors adjusted for potential confounders.

Results

A total of 1,327 patients were included. Lymph node involvement (pN+) was found in 1,026 patients (77%), 561 pN1 (55%) and 465 pN2 (45%). Median LNR in pN+ patients was 0.214 [interquartile range (IQR): 0.105-0.364]. On multivariable analysis, LNR was the strongest overall survival predictor in the entire cohort [hazard ratio (HR) =5.5; 95% confidence interval (CI): 3.1-9.9; P<0.001] and pN+ patients (HR =3.8; 95% CI: 2.2-6.6; P<0.001). Median overall survival was better in patients with LNR <0.225 compared to patients with LNR ≥0.225 in the entire cohort and pN+ patients. Similar results were found in pN2 patients (worse overall survival when LNR ≥0.225).

Conclusions

LNR appeared as an important prognostic factor in patients undergoing surgery for pancreatic adenocarcinoma and permitted to stratify overall survival in pN2 patients. LNR should be routinely used in complement to tumor-node-metastasis (TNM) stage to better predict patient prognosis.

CHRNB2 represses pancreatic cancer migration and invasion via inhibiting β-catenin pathway

Background

Pancreatic cancer is one of the most lethal disease with highly fatal and aggressive properties. Lymph node ratio (LNR), the ratio of the number of metastatic lymph nodes to the total number of examined lymph nodes, is an important index to assess lymphatic metastasis and predict prognosis, but the molecular mechanism underlying high LNR was unclear.

Methods

Gene expression and clinical information data of pancreatic cancer were obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). Patients in TCGA were averagely divided into low and high LNR groups. Then, Weighted Gene Co-expression Network Analysis (WGCNA) was utilized to build co-expression network to explore LNR-related modules and hub genes. GO and KEGG analysis was performed to find key pathways related to lymph node metastasis. Next, GSE101448 and the overall survival data in TCGA was employed to further select significant genes from hub genes. Considering the key role of CHRNB2 in LNR and survival, gene set enrichment analysis (GSEA) was applied to find pathways related to CHRNB2 expression in pancreatic cancer. The contribution of CHRNB2 to migrative and invasive ability of pancreatic cancer cells was confirmed by Transwell assays. We finally explored the role of CHRNB2 in EMT and β-catenin pathway via Western Blot.

Results

High LNR was significantly related to high T stages and poor prognosis. In WGCNA, 14 hub genes (COL5A1, FN1, THBS2, etc.) were positively related to high LNR, 104 hub genes (FFAR1, SCG5, TMEM63C, etc.) were negatively related to high LNR. After taking the intersection with GSE101448, 13 genes (CDK5R2, SYT7, CACNA2D2, etc.) which might prevent lymph node metastasis were further selected. Among them, CHRNB2 showed the strongest relationship with long survival. Moreover, CHRNB2 also negatively related to the T stages and LNR. Next, knockdown of CHRNB2 expression could acetylcholine (ACh)-independently increase the migration and invasion of pancreatic cancer cells, while CHRNB2 overexpression ACh-independently decrease the migration and invasion of pancreatic cancer cells. For exploring the underlying mechanism, CHRNB2 downregulated β-catenin pathway might through controlling its upstream regulators such as SOX6, SRY, SOX17, and TCF7L2.

Conclusions

CHRNB2 negatively relates to lymph node metastasis in pancreatic cancer patients. CHRNB2 could inhibit β-catenin pathway, EMT, migration and invasion of pancreatic cancer cells via ACh-independent mechanism.

Five-Year Outcomes of FOLFIRINOX vs Gemcitabine as Adjuvant Therapy for Pancreatic Cancer: A Randomized Clinical Trial

Importance

Early results at 3 years from the PRODIGE 24/Canadian Cancer Trials Group PA6 randomized clinical trial showed survival benefits with adjuvant treatment with modified FOLFIRINOX vs gemcitabine in patients with resected pancreatic ductal adenocarcinoma; mature data are now available.

Objective

To report 5-year outcomes and explore prognostic factors for overall survival.

Design, Setting, and Participants

This open-label, phase 3 randomized clinical trial was conducted at 77 hospitals in France and Canada and included patients aged 18 to 79 years with histologically confirmed pancreatic ductal adenocarcinoma who had undergone complete macroscopic (R0/R1) resection within 3 to 12 weeks before randomization. Patients were included from April 16, 2012, through October 3, 2016. The cutoff date for this analysis was June 28, 2021.

Interventions

A total of 493 patients were randomized (1:1) to receive treatment with modified FOLFIRINOX (oxaliplatin, 85 mg/m2 of body surface area; irinotecan, 150-180 mg/m2; leucovorin, 400 mg/m2; and fluorouracil, 2400 mg/m2, every 2 weeks) or gemcitabine (1000 mg/m2, days 1, 8, and 15, every 4 weeks) as adjuvant therapy for 24 weeks.

Main Outcomes and Measures

Primary end point was disease-free survival. Secondary end points included overall survival, metastasis-free survival, and cancer-specific survival. Prognostic factors for overall survival were determined.

Results

Of the 493 patients, 216 (43.8%) were women, and the mean (SD) age was 62.0 (8.9) years. At a median of 69.7 months' follow-up, 367 disease-free survival events were observed. In patients receiving chemotherapy with modified FOLFIRINOX vs gemcitabine, median disease-free survival was 21.4 months (95% CI, 17.5-26.7) vs 12.8 months (95% CI, 11.6-15.2) (hazard ratio [HR], 0.66; 95% CI, 0.54-0.82; P < .001) and 5-year disease-free survival was 26.1% vs 19.0%; median overall survival was 53.5 months (95% CI, 43.5-58.4) vs 35.5 months (95% CI, 30.1-40.3) (HR, 0.68; 95% CI, 0.54-0.85; P = .001), and 5-year overall survival was 43.2% vs 31.4%; median metastasis-free survival was 29.4 months (95% CI, 21.4-40.1) vs 17.7 months (95% CI, 14.0-21.2) (HR, 0.64; 95% CI, 0.52-0.80; P < .001); and median cancer-specific survival was 54.7 months (95% CI, 45.8-68.4) vs 36.3 months (95% CI, 30.5-43.9) (HR, 0.65; 95% CI, 0.51-0.82; P < .001). Multivariable analysis identified modified FOLFIRINOX, age, tumor grade, tumor staging, and larger-volume center as significant favorable prognostic factors for overall survival. Shorter relapse delay was an adverse prognostic factor.

Conclusions and Relevance

The final 5-year results from the PRODIGE 24/Canadian Cancer Trials Group PA6 randomized clinical trial indicate that adjuvant treatment with modified FOLFIRINOX yields significantly longer survival than gemcitabine in patients with resected pancreatic ductal adenocarcinoma.

Trial Registration

EudraCT: 2011-002026-52; ClinicalTrials.gov Identifier: NCT01526135.

Radiomics models based on multi-sequence MRI for preoperative evaluation of MUC4 status in pancreatic ductal adenocarcinoma: a preliminary study

BACKGROUND

Mucin 4 (MUC4) overexpression promotes tumorigenesis and increases the aggressiveness of pancreatic ductal adenocarcinoma (PDAC). To date, no study has reported the association between radiomics and MUC4 expression in PDAC. Thus, we aimed to explore the utility of radiomics based on multi-sequence magnetic resonance imaging (MRI) to predict the status of MUC4 expression in PDAC preoperatively.

METHODS

This retrospective study included 52 patients with PDAC who underwent MRI. The patients were divided into two groups based on MUC4 expression status. Two feature sets were extracted from the arterial and portal phases (PPs) of dynamic contrast-enhanced MRI (DCE-MRI). Univariate analysis, minimum redundancy maximum relevance (MRMR), and principal component analysis (PCA) were performed for the feature selection of each dataset, and features with a cumulative variance of 90% were selected to develop radiomics models. Clinical characteristics were gathered to develop a clinical model. The selected radiomics features and clinical characteristics were modeled by multivariable logistic regression. The combined model integrated radiomics features from different selected data sets and clinical characteristics. The classification metrics were applied to assess the discriminatory power of the models.

RESULTS

There were 22 PDACs with a high expression of MUC4 and 30 PDACs with a low expression of MUC4. The area under the receiver operating characteristic (ROC) curve (AUC) values of the arterial phase (AP) model, the PP model, and the combined model were 0.732 (0.591-0.872), 0.709 (0.569-0.849), and 0.861 (0.760-0.961), respectively. The AUC of the clinical model was 0.666 (0.600-0.682). The combined model that was constructed outperformed the AP, the PP, and the clinical models (P<0.05, although no statistical significance was observed in the combined model vs. AP model).

CONCLUSIONS

Radiomics models based on multi-sequence MRI have the potential to predict MUC4 expression levels in PDAC.

Reassessment of the Optimal Number of Examined Lymph Nodes in Pancreatoduodenectomy for Pancreatic Ductal Adenocarcinoma

OBJECTIVE

The aim of this study was to reappraise the optimal number of examined lymph nodes (ELNs) in pancreatoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC).

SUMMARY BACKGROUND DATA

The well-established threshold of 15 ELNs in PD for PDAC is optimized for detecting 1 positive node (PLN) per the previous 7th edition of the American Joint Committee on Cancer (AJCC) staging manual. In the framework of the 8th edition, where at least 4 PLN are needed for an N2 diagnosis, this threshold may be inadequate for accurate staging.

METHODS

Patients who underwent upfront PD at 2 academic institutions between 2000 and 2016 were analyzed. The optimal ELN threshold was defined as the cut-point associated with a 95% probability of identifying at least 4 PLNs in N2 patients. The results were validated addressing the N-status distribution and stage migration.

RESULTS

Overall, 1218 patients were included. The median number of ELN was 26 (IQR 17-37). ELN was independently associated with N2-status (OR 1.27, P < 0.001). The estimated optimal threshold of ELN was 28. This cut-point enabled improved detection of N2 patients and stage III disease (58% vs 37%, P = 0.001). The median survival was 28.6 months. There was an improved survival in N0/N1 patients when ELN exceeded 28, suggesting a stage migration effect (47 vs 29 months, adjusted HR 0.649, P < 0.001). In N2 patients, this threshold was not associated with survival on multivariable analysis.

CONCLUSION

Examining at least 28 LN in PD for PDAC ensures optimal staging through improved detection of N2/stage III disease. This may have relevant implications for benchmarking processes and quality implementation.

Pancreatic cancer - the past, the present, and the future

BACKGROUND

Pancreatic cancer has been and still is associated with a very poor prognosis. This is due to a lack of major breakthroughs with respect to early diagnosis, prognostication, prediction, as well as novel, targeted therapies. The benefits of surgery and chemotherapy are evident, but the fact that only some 10% of all patients have early, localized disease highlights the unmet need for new early detection methods. An improved understanding of tumor biology and the development of molecular markers detectable both in the circulation and in cancer tissues may underlie the development of new tools for optimizing both diagnosis and treatment.

MATERIAL AND METHODS

Review of the literature.

RESULTS AND CONCLUSION

If we do not improve precision oncology for pancreatic ductal adenocarcinoma, the prognosis will still remain dismal and the" burden" on society will increase substantially.

Lymph node ratio is a superior predictor in surgically treated early-onset pancreatic cancer

Background

The prognostic performance of four lymph node classifications, the 8th American Joint Committee on Cancer (AJCC) Tumor Node Metastasis (TNM) N stage, lymph node ratio (LNR), log odds of positive lymph nodes (LODDS), and examined lymph nodes (ELN) in early-onset pancreatic cancer (EOPC) remains unclear.

Methods

The Surveillance, Epidemiology, and End Results (SEER) database was searched for patients with EOPC from 2004 to 2016. 1048 patients were randomly divided into training (n = 733) and validation sets (n = 315). The predictive abilities of the four lymph node staging systems were compared using the Akaike information criteria (AIC), receiver operating characteristic area under the curve (AUC), and C-index. Multivariate Cox analysis was performed to identify independent risk factors. A nomogram based on lymph node classification with the strongest predictive ability was established. The nomogram’s precision was verified by the C-index, calibration curves, and AUC. Kaplan–Meier analysis and log-rank tests were used to compare differences in survival at each stage of the nomogram.

Results

Compared with the 8th N stage, LODDS, and ELN, LNR had the highest C-index and AUC and the lowest AIC. Multivariate analysis showed that N stage, LODDS, LNR were independent risk factors associated with cancer specific survival (CSS), but not ELN. In the training set, the AUC values for the 1-, 3-, and 5-year CSS of the nomogram were 0.663, 0.728, and 0.760, respectively and similar results were observed in the validation set. In addition, Kaplan–Meier survival analysis showed that the nomogram was also an important factor in the risk stratification of EOPC.

Conclusion

We analyzed the predictive power of the four lymph node staging systems and found that LNR had the strongest predictive ability. Furthermore, the novel nomogram prognostic staging mode based on LNR was also an important factor in the risk stratification of EOPC.

Prognosis of pancreatic head cancer with different patterns of lymph node metastasis

BACKGROUND

The nodal stage of pancreatic ductal adenocarcinoma (PDAC) is revised in the AJCC 8th edition. Studies on the prognosis of PDAC according to lymph node metastasis (LNM) are still ongoing. We attempted to find the patterns of nodal involvement and to reveal its clinical significance to overall survival (OS).

METHODS

We analyzed 585 patients who received pancreatic head cancer surgery diagnosed as PDAC from January 2007 to December 2016. Patients were classified into three groups: Group 1 (G1, patients without LNM), Group 2 (G2, those with LNM only in the peripancreatic area), and Group 3 (G3 those with LNM in the other area and/or peripancreatic LNM). Risk factors were analyzed by Cox-regression test and overall survival was compared by Kaplan-Meier analysis.

RESULTS

LNM in peripancreatic area was the most common (88.7%). In the multivariate analysis, T stage, nuclear differentiation, adjuvant treatment, and the G2 and G3 were independent risk factors for OS (G2 over G1, HR 1.384, 95% CI 1.046-1.802; P = .036 and G3 over G1, HR 2.383, 95% CI 1.378-4.103; P = .001). G3 showed worse OS than G2 (P = .006). In the N1 status, LNM to the pericholedochal (PC) and superior mesenteric artery (SMA) areas resulted in worse OS than the G2 (P = .011 and P = .019).

CONCLUSIONS

We found that LNM beyond the peripancreatic area significantly affects OS in pancreatic head cancer patients. Depending on the station of the LNM, different risk-stratification and treatment strategies will need to be considered.

Complications in Distal Pancreatectomy versus Radical Antegrade Modular Pancreatosplenectomy: A Disease Risk Score Analysis Utilizing National Surgical Quality Improvement Project Data

INTRODUCTION

Radical antegrade modular pancreatosplenectomy (RAMPS) was developed to improve R0 resections and lymph node harvests versus distal pancreatectomy (DP) in pancreatic adenocarcinoma (PDAC); relative complication rates are understudied.

METHODS

Patients undergoing distal pancreas resections from 2006 to 2020 were identified from our institutional NSQIP database, grouped by resection method, and evaluated for the following outcomes: postoperative pancreatic fistula (POPF), clinically relevant POPF (crPOPF), incisional surgical site infection (iSSI), organ space SSI (osSSI), and Clavien-Dindo grade ≥ 3 (CD ≥ 3) complications using logistic regression. Patients were matched 1:1 based on disease risk score.

RESULTS

Two-hundred-thirty-six and 117 patients underwent DP and RAMPS, respectively. POPF, crPOPF, CD ≥ 3 complications, iSSI, and osSSIs occurred in 105 (30%), 43 (12%), 74 (21%), 34 (10%) and 52 (15%) patients, respectively. Disease risk score matching yielded 89 similar patients per group. On multivariable analysis, patients undergoing RAMPS were not significantly more likely to experience POPF (OR 0.69, P = 0.26), crPOPF (OR 0.41, P = 0.72), CD ≥ 3 complication (OR 0.78, P = 0.44), iSSI (OR 0.58, P = 0.27), or osSSI (OR 0.93, P = 0.86). Of patients with PDAC (n = 108) mean nodal harvest were 14.8 (SD 11.30) and 19.4 (SD 7.19) nodes for patients undergoing DP and RAMPS, respectively (P = 0.01). Six patients (20%) undergoing DP had positive margins versus 12 (15%) undergoing RAMPS (P = 0.56). At a median follow-up of 17 months, there was no difference in locoregional recurrence-free survival (P = 0.32) or overall survival (P = 0.92) on Kaplan-Meier analysis.

CONCLUSION

RAMPS does not result in increased complications compared to DP and routine use is encouraged in pancreatic malignancies.

Para-aortic lymph node involvement should not be a contraindication to resection of pancreatic ductal adenocarcinoma

BACKGROUND

Para-aortic lymph nodes (PALN) are found in the aortocaval groove and they are staged as metastatic disease if involved by pancreatic ductal adenocarcinoma (PDAC). The data in the literature is conflicting with some studies having associated PALN involvement with poor prognosis, while others not sharing the same results. PALN resection is not included in the standard lymphadenectomy during pancreatic resections as per the International Study Group for Pancreatic Surgery and there is no consensus on the management of these cases.

AIM

To investigate the prognostic significance of PALN metastases on the oncological outcomes after resection for PDAC.

METHODS

This is a retrospective cohort study of data retrieved from a prospectively maintained database on consecutive patients undergoing pancreatectomies for PDAC where PALN was sampled between 2011 and 2020. Statistical comparison of the data between PALN+ and PALN- subgroups, survival analysis with the Kaplan-Meier method and risk analysis with univariable and multivariable time to event Cox regression analysis were performed, specifically assessing oncological outcomes such as median overall survival (OS) and disease-free survival (DFS).

RESULTS

81 cases had PALN sampling and 17 (21%) were positive. Pathological N stage was significantly different between PALN+ and PALN- patients (P = 0.005), while no difference was observed in any of the other characteristics. Preoperative imaging diagnosed PALN positivity in one case. OS and DFS were comparable between PALN+ and PALN- patients with lymph node positive disease (OS: 13.2 mo vs 18.8 mo, P = 0.161; DFS: 13 mo vs 16.4 mo, P = 0.179). No difference in OS or DFS was identified between PALN positive and negative patients when they received chemotherapy either in the neoadjuvant or in the adjuvant setting (OS: 23.4 mo vs 20.6 mo, P = 0.192; DFS: 23.9 mo vs 20.5 mo, P = 0.718). On the contrary, when patients did not receive chemotherapy, PALN disease had substantially shorter OS (5.5 mo vs 14.2 mo; P = 0.015) and DFS (4.4 mo vs 9.8 mo; P < 0.001). PALN involvement was not identified as an independent predictor for OS after multivariable analysis, while it was for DFS doubling the risk of recurrence.

CONCLUSION

PALN involvement does not affect OS when patients complete the indicated treatment pathway for PDAC, surgery and chemotherapy, and should not be considered as a contraindication to resection.

Baseline CT-based Radiomic Features Aid Prediction of Nodal Positivity after Neoadjuvant Therapy in Pancreatic Cancer

Purpose To study the association between CT-derived textural features of pancreatic cancer and patient outcome. Materials and Methods This retrospective study evaluated 54 patients (median age, 62 years [range, 40-88 years]; 32 men) with pancreatic cancer who underwent chemoradiation followed by surgical resection and lymph node dissection from May 2012 to June 2016. Three-dimensional segmentation of the pancreatic tumor was performed on baseline dual-energy CT images: 70-keV pancreatic parenchymal phase (PPP) images and iodine material density images. Then, 15 and 19 radiomic features were extracted from each phase, respectively. Logistic regression with elastic net regularization was used to select textural features associated with outcome, and receiver operating characteristic analysis evaluated feature performance. Survival curves were generated using the Kaplan-Meier method. Results The feature of integral total (∫ T), representing the mean intensity in Hounsfield units times the contour volume in milliliters of PPP imaging (hereafter, "∫ T (HU·mL) (PPP)"), is inversely associated with posttherapy pathologic lymph node (ypN) category. A threshold ∫ T (HU·mL) (PPP) less than 507.85 predicted ypN1-2 classification with 96% sensitivity, 34% specificity, and area under the curve of 0.61. Patients with an ∫ T (HU·mL) (PPP) of less than 507.85 had decreased overall survival (median, 2.8 years) compared with patients with an ∫ T (HU·mL) (PPP) of 507.85 or greater (one event at 3.4 years) (P = .006). Patients with an ∫ T (HU·mL) (PPP) of less than 507.85 had decreased progression-free survival (median, 1.5 years) compared with patients with an ∫ T (HU·mL) (PPP) of 507.85 or greater (median, 2.7 years) (P = .001). Conclusion A CT-based radiomic signature may help predict ypN category in patients with pancreatic cancer. Keywords: CT-Dual Energy, Abdomen/GI, Pancreas, Tumor Response, Outcomes Analysis © RSNA, 2022 Supplemental material is available for this article.

Accurate Nodal Staging in Pancreatic Cancer in the Era of Neoadjuvant Therapy

BACKGROUND

Nodal disease is prognostic in pancreatic ductal adenocarcinoma (PDAC); however, optimal number of examined lymph nodes (ELNs) required to accurately stage nodal disease in the current era of neoadjuvant therapy remains unknown. The aim of the study was to evaluate the optimal number of ELNs in patients with neoadjuvantly treated PDAC.

METHODS

A retrospective study was performed on patients with PDAC undergoing resection following neoadjuvant treatment between 2011 and 2018. Clinicopathological data were extracted and analyzed.

RESULTS

Of 546 patients included, 232 (42.5%) had lymph node metastases. The median recurrence free survival (RFS) was 10.6 months (95% confidence interval: 9.7-11.7) and nodal disease was independently associated with shorter RFS (9.1 vs 11.9 months; p < 0.001). A cutoff of 22 ELNs was identified that stratified patients by RFS. Patients with N1 and N2 disease had similar median RFS (9.1 vs 8.9 months; p = 0.410). On multivariable analysis, ELN of ≥ 22 was found to be significantly associated with longer RFS among patients with N0 disease (14.2 vs. 10.9 months, p = 0.046). However, ELN has no impact on RFS for patients with N1/N2 disease (9.5 vs. 8.4 months, p = 0.190). Adjuvant therapy was associated with RFS only in patients with residual nodal disease.

CONCLUSIONS

Lymph node metastases remain prognostic in PDAC patients after neoadjuvant treatment. Among N0 patients, a cutoff of 22 ELN was associated with improved RFS and resulted in optimal nodal staging.

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.

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.

Surgery for pancreatic cancer: current controversies and challenges

Two areas that remain the focus of improvement in pancreatic cancer include high post-operative morbidity and inability to uniformly translate surgical success into long-term survival. This narrative review addresses specific aspects of pancreatic cancer surgery, including neoadjuvant therapy, vascular resections, extended pancreatectomy, extent of lymphadenectomy and current status of minimally invasive surgery. R0 resection confers longer disease-free survival and overall survival. Vascular and adjacent organ resections should be undertaken after neoadjuvant therapy, only if R0 resection can be ensured based on high-quality preoperative imaging, and that too, with acceptable post-operative morbidity. Extended lymphadenectomy does not offer any advantage over standard lymphadenectomy. Although minimally invasive distal pancreatectomies offers some short-term benefits over open distal pancreatectomy, safety remains a concern with minimally invasive pancreatoduodenectomy. Strict adherence to principles and judicious utilization of surgery within a multimodality framework is the way forward.

The prognostic value of lymph node ratio in comparison to positive lymph node count in penile squamous cell carcinoma

PURPOSE

Penile cancer is a rare male neoplasm with a wide variation in its global incidence. In this study, the prognostic value of lymph node ratio (LNR) was compared to that of positive lymph node count (PLNC) in penile squamous cell carcinoma.

METHODS

A total of 249 patients with penile squamous cell carcinoma were enrolled from The Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2015. The X-tile program was used to calculate the optimal cut-off values of LNR and PLNC that discriminate survival. We used the χ2 or the Fisher exact probability test to assess the association between clinical-pathological characteristics and LNR or PLNC. Univariate and multivariate Cox regression analyses were performed to identify independent prognostic factors for survival. Spearman correlation analysis was used to determine the correlation between LNR and PLNC.

RESULTS

We found that patients with high LNR tended to have advanced N stage, the 7th AJCC stage, and higher pathological grade, while patients with high PLNC had advanced N stage and the 7th AJCC stage. Univariate Cox regression analysis revealed that the N stage, M stage, the 7th AJCC stage, lymph-vascular invasion, LNR, and PLNC were significantly associated with prognosis. Multivariate Cox regression analysis demonstrated that LNR rather than PLNC was an independent prognostic factor for cancer-specific survival. Subgroup analysis of node-positive patients showed that LNR was associated with CSS, while PLNC was not.

CONCLUSION

LNR was a better predictor for long-term prognosis than PLNC in patients with penile squamous cell carcinoma.

Safety and effectiveness of open pancreaticoduodenectomy in adults aged 70 or older: A meta-analysis

BACKGROUND

Pancreaticoduodenectomy (PD) is considered the most complicated operation in abdominal surgery. The safety and effectiveness of PD in older patients has been questionable because older adults are often beset by one or more systemic diseases and have poor surgical tolerance.

AIM

To evaluate the safety and effectiveness of PD in patients aged 70 or older.

METHODS

We conducted a literature search on PubMed, EMBASE, Cochrane Library and other databases to discover all literature reporting a comparison of the efficacy of PD in patients 70 years old and older versus patients under 70 years old. Our cutoff date is August 2020. Revman5.3 statistical software was used for the analysis.

RESULTS

Twenty cohort studies were determined to be eligible with a total of 6508 patients; 2274 patients were 70 years old and older and 4234 patients under 70 years old. Meta-analysis results showed that after PD in patients over 70 years of age and older the mortality rate (RR = 2.1, 95%CI:1.59-2.78, p < 0.001), the overall postoperative complications (RR = 1.16,95%CI:1.09-1.23, p < 0.001), intraoperative transfusions (RR = 1.38, 95%CI:1.14-1.23, p = 0.001), severe complications (RR = 1.30,95%CI:1.11-1.52, p = 0.001), the re-operation rate (RR = 1.23,95%CI:1.00-1.51, p = 0.05), the R0 rate (RR = 0.92,95%CI:0.86-0.98, p = 0.01), lymph node dissection (WMD = -4.61,95%CI:-7.24-1.97, p < 0.001) and delayed gastric emptying (RR = 1.24,95%CI:1.04-1.49, p = 0.02) at a rate significantly higher than that of patients under 70 years old. There is no significant difference between patients 70 years old and older and patients under 70 years old in the clinical PF (RR = 1.11,95%CI:0.93-1.34, p = 0.24), bile leakage (RR = 0.68,95%CI:0.41-1.12, p = 0.13), postoperative bleeding (RR = 1,95%CI:0.76-1.30, p = 0.98), wound infection (RR = 1.15,95%CI:0.95-1.39, p = 0.15) and hospital stays (RR = 0.30,95%CI:-1.77-2.37, p = 0.77).

CONCLUSION

Patients aged 70 years or older have approximately double the risk of postoperative mortality following PD and a higher risk of overall and severe postoperative complications. Furthermore, patients 70 years old and older require more frequent intraoperative transfusions, re-operative interventions and have poorer oncology results (lower R0 rate and fewer lymph node dissections). More multi-center, large sample, and high-quality research is still needed to further verify this conclusion.

Impact of Lymph Node Metastases Around the Superior Mesenteric Artery on Postoperative Outcomes of Pancreatic Head Cancer

BACKGROUND

The neural plexus and lymph nodes around the superior mesenteric artery (LN#14), are the most frequent sites involved by pancreatic head cancer. However the influence of metastases to LN#14 on patients' prognosis has rarely been evaluated.

METHODS

The patients who underwent pancreatectomy for pancreatic head cancer between January 2010 and December 2018 were selected. The patients with nodal metastases were classified into an LN#14 + or LN#14-group according to LN#14 metastasis. Clinical and pathological characteristics and prognosis were compared between the two groups.

RESULTS

In total, 99 patients underwent pancreatectomy. Ninety-four patients were positive for lymph node metastases and 14 and 80 were classified as LN#14 + and LN#14 - , respectively. Postoperative median overall survival (OS) of the LN#14 + and LN#14 - groups was 10.2 and 31.1 months, respectively (P < 0.001). Median OS of the LN#14 + group was worse than that of patients with ≥ 4 metastatic nodes in the LN#14 - group (n = 35, 24.7 months, P = 0.002). In multivariate analysis, LN#14 + (hazard ratio [HR] = 3.89, 95% confidence interval [CI], 1.64-8.86) was one of the independent predictors of worse OS.

CONCLUSION

It might be feasible to recognize LN#14 metastases as an important prognostic factor independently from other regional lymph node metastases.

Dataset for the reporting of carcinoma of the exocrine pancreas: recommendations from the International Collaboration on Cancer Reporting (ICCR)

BACKGROUND AND OBJECTIVES

Current guidelines for the pathology reporting on pancreatic cancer differ in certain aspects, resulting in divergent reporting practice and a lack of comparability of data. Here we report on a new international dataset for the pathology reporting of resection specimens with cancer of the exocrine pancreas (ductal adenocarcinoma and acinar cell carcinoma). The dataset was produced under the auspices of the International Collaboration on Cancer Reporting (ICCR), a global alliance of major (inter-)national pathology and cancer organisations.

METHODS AND RESULTS

According to the ICCR's rigorous process for dataset development, an international expert panel consisting of pancreatic pathologists, a pancreatic surgeon and an oncologist produced a set of core and non-core data items based on a critical review and discussion of current evidence. Commentary was provided for each data item to explain the rationale for selecting it as a core or non-core element, its clinical relevance, and to highlight potential areas of disagreement or lack of evidence, in which case a consensus position was formulated. Following international public consultation, the document was finalised and ratified, and the dataset, which includes a synoptic reporting guide, was published on the ICCR website.

CONCLUSIONS

This first international dataset for cancer of the exocrine pancreas is intended to promote high quality, standardised pathology reporting. Its widespread adoption will improve consistency of reporting, facilitate multidisciplinary communication and enhance comparability of data, all of which will help to improve the management of pancreatic cancer patients.

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.

Prognostic Nomograms Based on Three Lymph Node Classification Systems for Resected Gastric Adenocarcinoma: A Large Population-Based Cohort Study and External Validation

BACKGROUNDS

The optimal lymph node classification system for prognostic assessment in gastric adenocarcinoma (GAC) patients who undergo lymph node dissection remains unclear. Therefore, this study aimed to compare prognostic nomograms based on AJCC N stage, lymph node ratio (LNR), and log odds of metastatic lymph nodes (LODDS) to evaluate the prognosis and differentiate risk subgroups of patients with resected GAC.

PATIENTS AND METHODS

We collected 4633 patients with resected stage I-III GAC receiving chemotherapy from the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2015. Independent prognostic factors were selected by Cox regression analyses, based on which nomograms were constructed. External validation was performed in 228 cases from Nanjing Drum Tower Hospital. Kaplan-Meier survival analysis was used to evaluate the effect of postoperative radiotherapy (PORT) for different lymph node classifications.

RESULTS

Multivariate analysis indicated that age, grade, primary site, T stage, N stage, LNR, LODDS, and radiotherapy were independent predictors. Good discrimination power and high consistency of calibration plots were obtained from the LODDS system nomogram. The LODDS classification could more precisely differentiate risk subgroups and improve the discrimination of the resected GAC prognosis. A user-friendly webserver of LODDS system was built based on the nomogram for convenient clinical application.

CONCLUSIONS

The LODDS seems to be the most reliable lymph node classification in predicting the prognosis of patients with resected GAC and should be recommended in clinical prognostic assessment. Incorporating LODDS into the staging system will enable clinicians to more accurately predict prognosis and guide radiotherapy regimen decisions.

Re-appraising the role of lymph node status in predicting survival in resected distal cholangiocarcinoma - A meta-analysis and systematic review

This systematic review and meta-analysis aimed to confirm the prognostic value of lymph node ratio (LNR), and determine an optimal LNR cut-off for overall survival (OS) in patients with distal cholangiocarcinoma (DCC) undergoing curative surgery. We additionally aimed to provide a consolidated review of current evidence regarding prognostic significance of positive lymph node count (PLNC) and total lymph node count (TLNC). A systematic search of PubMed, EMBASE and Cochrane Library was conducted from inception to October 2020. Studies were included into meta-analysis if there was histological diagnosis, curative surgery, restriction to DCC and relevant LNR results. Quality assessment was performed using the Newcastle Ottawa Scale. Findings for 1228 patients were pooled across 6 studies. Meta-analysis delineated a dose-effect gradient in which higher LNR cut-offs correlated with larger pooled hazard ratios: 0<LNR<0.2 (HR 1.54; 95% CI 1.08-2.20; p = 0.02), LNR>0.2 (HR 3.26; 95% CI 2.07-5.13; p < 0.00001) and LNR>0.4 (HR 3.59; 95% CI 2.31-5.58; p < 0.00001) when compared against a control group of LNR = 0. LNR of 0.2 (HR 2.12; 95% CI: 1.57-2.86; p < 0.0001) was found to be a significant and ideal cut-off for prognostication of poorer OS. A review of current literature reveals an ongoing debate regarding the comparative prognostic value of differing PLNC cut-offs (0/1/3 versus 0/1/4). TLNC of 10-13 is widely reported to be the minimum necessary to ensure improved long term outcomes. PLNC and LNR are strong prognostic factors for OS in DCC. An ideal LNR cut-off of 0.2 is most significantly associated with poorer OS.

Safety and efficacy of robot-assisted versus open pancreaticoduodenectomy: a meta-analysis of multiple worldwide centers

The objective of the study is to compare the safety and efficacy of robot-assisted pancreaticoduodenectomy (PD) with open PD. The PubMed, EMBASE and Cochrane Library databases were searched for the literature available from their respective inception dates up to May 2020 to find studies comparing robot-assisted pancreaticoduodenectomy (RPD) with open pancreaticoduodenectomy (OPD). The RevMan 5.3 statistical software was used for analysis to evaluate surgical outcome and oncology safety. The combination ratio (RR) and weighted mean difference (WMD) and their 95% confidence intervals (CIs) were calculated using fixed-effect or random effect models. 18 cohort studies from 16 medical centers were eligible with a total of 5795 patients including 1420 RPD group patients and 4375 OPD group patients. The RPD group fared better than the OPD group in terms of estimated blood loss (EBL) (WMD = - 175.65, 95% CI (- 251.85, - 99.44), P < 0.00001), wound infection rate (RR = 0.60, 95% CI (0.44, 0.81), P = 0.001), reoperation rate (RR = 0.61, 95% CI (0.41, 0.91), P = 0.02), hospital day (WMD = - 2.95, 95% CI (- 5.33, - 0.56), P = 0.02), intraoperative blood transfusion (RR = 0.56, 95% CI (0.42, 0.76), P = 0.0001), overall complications (RR = 0.78, 95% CI (0.64, 0.95), P = 0.01), and clinical postoperative pancreatic fistula (POPF) (RR = 0.54, 95% CI (0.41, 0.70), P < 0.0001). In terms of lymph node clearance (WMD = 0.48, 95% CI (- 2.05, 3.02), P = 0.71), R0 rate (RR = 1.05, 95% CI (1.00, 1.11), P = 0.05), postoperative pancreatic fistula (RR = 1, 95% CI (0.85, 1.19), P = 0.97), bile leakage (RR = 0.99, 95% CI (0.54, 1.83), P = 0.98), delayed gastric emptying (DGE) (RR = 0.79, 95% CI (0.60, 1.03), P = 0.08), 90-day mortality (RR = 0.82, 95% CI (0.62, 1.10), P = 0.19), and severe complications (RR = 0.98, 95% CI (0.71, 1.36), P = 0.91), and there were no significant differences between the two groups. Robotic surgery was inferior to open surgery in terms of operational time (WMD = 80.85, 95% CI (16.09, 145.61), P = 0.01). RPD is not inferior to OPD, and it is even more advantageous for EBL, wound infection rate, reoperation rate, hospital stay, intraoperative transfusion, overall complications and clinical POPF. However, these findings need to be further verified by high-quality randomized controlled trials.

Construction and Validation of Novel Nomograms for Predicting Prognosis of Pancreatic Ductal Adenocarcinoma After Surgery According to Different Primary Cancer Locations

Background/Aims

Pancreatic ductal adenocarcinoma (PDAC) can occur in different parts of the pancreas. This study aimed to identify clinicopathological characteristics independently correlated with the prognosis of PDAC of the pancreatic head/uncinate (PHC) or body-tail (PBTC), and to develop novel nomograms for predicting cancer-specific survival (CSS) according to different primary cancer locations.

Methods

1160 PDAC patients were retrospectively enrolled and assigned to training and test sets with each set divided into PHC and PBTC groups. Comparative analysis of clinicopathologic characteristics, survival analysis, and multivariate analysis were performed. Independent factors were identified and used for constructing nomograms. The performance of the nomograms was validated in the test set.

Results

Primary tumor location was an independent risk factor for prognosis of PDAC after surgery. Specially, gender, fasting blood glucose, and preoperative cancer antigen 19-9 were significantly associated with prognosis of PHC, whereas age, body mass index, and lymph nodes were significantly correlated with the prognosis of PBTC. A significant difference in prognosis was found between PHC and PBTC in stage Ia and stage III. Three nomograms were established for predicting the prognosis for PDAC, PHC, and PBTC. Notably, these nomograms were calibrated modestly (c-indexes of 0.690 for PDAC, 0.669 for PHC, and 0.704 for PBTC), presented better accuracy and reliability than the 8^th AJCC staging system, and achieved clinical validity.

Conclusions

PHC and PBTC share the differential clinical-pathological characteristics and survival. The nomograms show good performance for predicting prognosis in PHC and PBTC. Therefore, these nomograms hold potential as novel approaches for predicting survival of PHC and PBTC patients after surgery.

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.

Predictive Value of Lymph Node Ratio in Patients with Pancreatic Cancer Treated with Pancreatoduodenectomy

Background: Recently, the predictive value of lymph node ratio (LNR, the ratio of metastatic lymph nodes to total examined lymph nodes) has been evaluated in patients with gastrointestinal malignancies, including pancreatic cancer. However, there is not enough evidence about the prognostic value of this factor. Objectives: We aimed at determining the value of LNR in predicting the survival of patients who have undergone the Whipple procedure. Methods: This cohort study was performed on 96 patients with pancreatic cancer undergoing the Whipple procedure during 2014 - 2019. Demographic, clinical, and pathological data of the patients were extracted from their records and patients' survival status was determined through follow-up. LNR and its effect on survival was calculated using the Cox model. Results: Of the 96 eligible patients, 51 (53.13%) were men. The mean age of the patients was 57.1 ± 14.1 (range: 19 - 82) years. The median total lymph nodes examined was 7 (range: 1 - 27), and no metastatic lymph nodes were found in 57 (59.37%) patients. The median involved lymph nodes and LNR were 2 and 0.17, respectively. Patients with LNR > 0.20 had the lowest 1 and 3-year survival rates. Age (P = 0.04), surgical radial margin (P = 0.001), lymph node status (N0, N1) (P = 0.01), and LNR (P = 0.01) were the most important prognostic factors for survival. Conclusions: LNR is a valuable indicator that can be used in patients with lymph node involvement as a prognostic factor for poor survival after the Whipple procedure. The lowest 1, 3, and 5-year survival rates were seen in patients with LNR > 0.20.

Number of Positive Lymph Nodes Is Superior to LNR and LODDS for Predicting the Prognosis of Pancreatic Neuroendocrine Neoplasms

BACKGROUND

The American Joint Committee on Cancer (AJCC) staging for pancreatic neuroendocrine neoplasms (PanNENs) based on the number of positive lymph nodes (PLNs) is the most widely accepted nodal staging system. New nodal staging schemes that take both the number of PLNs and the number of examined lymph nodes into consideration have emerged as useful prognostic tools. The aim of the current study was to determine the most effective nodal staging system, among the 8th edition AJCC N staging (or PLN staging), lymph node ratio (LNR), and log odds of positive lymph nodes (LODDS), for predicting the cause-specific survival of patients with PanNENs.

METHODS

The clinicopathological and prognostic data of 2,295 patients from the Surveillance, Epidemiology, and End Results (SEER) database, diagnosed with PanNENs between 1988 and 2015, were reviewed retrospectively.

RESULTS

A multivariate analysis identified PLN and LNR staging as independent prognostic factors, but not LODDS. The PLN staging exhibited higher C-index and area under the curve values than those of the LNR and LODDS, indicating better predictive discriminatory capacity. No significant difference in the survival of patients was observed within the same PLN staging subgroup according to the number (high or low) of examined lymph nodes. In contrast, intra-group heterogeneity was seen with use of LNR and LODDS staging, due to overestimation of the risk of insufficient examined lymph nodes, and LODDS failed to stratify patients without lymph nodes metastasis into different risk groups.

CONCLUSIONS

The PLN staging is more reliable than LNR and LODDS staging for predicting the cause-specific survival of PanNENs.

Complete Lymphadenectomy Around the Entire Superior Mesenteric Artery Improves Survival in Artery-First Approach Pancreatoduodenectomy for T3 Pancreatic Ductal Adenocarcinoma

BACKGROUND

Artery-first approach pancreatoduodenectomy (AFA-PD) is an important technique for treating pancreatic ductal adenocarcinoma (PDAC). However, it remains unknown whether performing complete lymphadenectomy around the entire superior mesenteric artery (SMA) is associated with better outcomes. In this retrospective study, we aimed to investigate whether this approach improved overall and recurrence-free survival in patients with PDAC.

METHODS

We identified 88 patients with T3 PDAC who underwent PD at St. Marianna University School of Medicine, Kawasaki, Japan, between April 2005 and October 2017. Two groups were defined: an "AFA-PD group" (n = 45) who had undergone AFA-PD in addition to complete lymphadenectomy around the entire SMA, and a "conventional PD group" (n = 43) in whom complete lymphadenectomy had not been performed (conventional group). Univariate and multivariate survival analyses were performed to identify risk factors for overall and disease-free survival.

RESULTS

The AFA-PD group had a longer median survival time (40.3 vs. 22.6 months; p = 0.0140) and a higher 5-year survival rate (40.3% vs. 5.9%, p = 0.005) than the conventional PD group. Multivariate analysis showed that AFA-PD with complete lymphadenectomy around the entire SMA was an independent factor for improved overall survival (p = 0.022). Recurrences around the SMA were significantly less frequent in the AFA-PD group than in the conventional group (22.2% vs. 44.2%, p = 0.041).

CONCLUSIONS

AFA-PD with complete lymphadenectomy around the entire SMA can prevent recurrences around the SMA and may prolong overall survival in patients with PDAC.