Nodal counts and lymph node ratio impact survival after distal pancreatectomy for pancreatic adenocarcinoma

Prognostic value of margin clearance in total and distal pancreatectomy specimens with pancreatic ductal adenocarcinoma in a Danish population-based nationwide study

BACKGROUND

The prognostic role of resection margin status following total (TP) and distal (DP) pancreatectomy for pancreatic ductal adenocarcinoma (PDAC) is insufficiently evaluated. In Denmark, pancreatic surgery, including the postoperative pathological examination of the resection specimens, is confined to four centres, all reporting to the Danish Pancreatic Cancer Database (DPCD). In this Danish population-based nationwide study on TP and DP for PDAC from 2015-2019, based on data from DPCD, we evaluated whether there is a prognostically relevant minimum margin clearance definition and whether certain margins hold independent prognostic information.

METHODS

Clinical and pathological data were retrieved from DPCD and supplemented by review of pathology reports and re-microscopy, if needed. One of the study pathologists performed all re-microscopy. The prognostic significance of margin status was evaluated by dichotomisation of the TP cohort (n = 101) and the DP cohort (n = 90) into involved and uninvolved groups, using different clearance definitions (0.5 - ≥3.0 mm).

RESULTS

Following TP, direct involvement of the superior mesenteric artery (SMA) margin had independent prognostic value. When using a clearance definition of ≥ 0.5 or ≥ 1.5 mm for SMA, median survival for R0 versus R1 was 19 (95% CI 14-26) versus 10 (95% CI 5-20) months (p = 0.010), and 21 (95% CI 15-30) versus 10 (95% CI 8-19) months (p = 0.011), respectively. Overall margin status was not of significant prognostic importance following neither DP nor TP.

CONCLUSION

In this Danish population-based nationwide study, SMA margin involvement was a significant isolated prognostic factor following TP, whereas combined assessment of all circumferential margins did not hold statistically significant prognostic information. Following DP, resection margin status did not affect survival.

Discordance Between Conventional and Detailed Lymph Node Analysis in Resected, Node-negative Pancreatic or Ampullary Adenocarcinomas and Association With Adverse Survival Outcomes: A Single-institution Analysis

OBJECTIVE

To assess the frequency of occult metastases (OM) in patients with resected pancreatic ductal adenocarcinoma (PDAC) or ampullary adenocarcinoma (AA) discovered on detailed pathologic examination on lymph nodes (LNs) previously considered negative by conventional analysis and to examine the association between OM and overall survival (OS).

BACKGROUND

Poor prognosis of patients with no pathologic evidence of LN metastases may be due to OM that is not detected on conventional LN analysis.

METHODS

Patients with LN-negative resected PDAC or AA (2010-2020) were identified from our institutional database. Original hematoxylin and eosin ( H and E ) slides were reanalyzed. In addition, selected LN were analyzed by H and E (3 sections/LN) and pan-cytokeratin (AE1-AE3/PCK26) immunohistochemistry.

RESULTS

A total of 598 LNs from 74 LN-negative patients were reexamined. Nineteen patients (25.7%) had OM; 9 (47.4%) were found with immunohistochemistry but not on H and E . The number of positive LNs ranged from 1 to 3. No clinicodemographic, pathologic, or treatment-related factors were associated with OM. On conventional LN analysis, 3/19 patients (15.8%) had stage IA, 9/34 (26.5%) had stage IB, and 7/19 (36.8%) had stage IIA. On detailed LN analysis, 11/19 patients (57.9%) were upstaged to IIB, whereas 8/19 (42.1%) had isolated tumor cells only (N0i+). OM was associated with shorter OS (median OS: 22.3 vs 50.5 months; hazard ratio=3.95, 95% CI: 1.58-9.86).

CONCLUSIONS

There is a 26% discordance rate between conventional and detailed LN pathologic analysis in resected PDAC and AA. The presence of OM is associated with shorter OS.

Role of adjuvant chemotherapy on recurrence and survival in patients with resected ampulla of Vater carcinoma

BACKGROUND

Owing to rarity of disease and lack of prospective studies, data supporting the role of adjuvant chemotherapy in ampulla of Vater (AoV) carcinoma is limited.

AIM

To evaluate whether adjuvant chemotherapy cases for AoV carcinoma had better disease-free survival (DFS) rates than cases of observation following curative surgery.

METHODS

We retrospectively analyzed the association between adjuvant chemotherapy and DFS and overall survival (OS) in patients with stage IB-III AoV carcinoma who underwent curative surgical resection. Fluorouracil-based adjuvant chemotherapy was administered after surgery at the discretion of the physician. Adjusted multivariate regression models were used to evaluate the association between adjuvant chemotherapy and survival outcomes.

RESULTS

Of the total 104 patients who underwent curative surgery, 52 received adjuvant chemotherapy. Multivariate analysis revealed that higher histologic grade [hazard ratio (HR) = 2.24, P = 0.046], advanced tumor stage (HR = 1.85, P = 0.030), and vascular invasion (HR = 2.14, P = 0.010) were associated with shorter DFS. Adjuvant chemotherapy improved DFS compared to the observation group (HR = 0.50, P = 0.015) and tended to be associated with a longer OS, although the difference was not statistically significant (HR = 0.58, P = 0.098).

CONCLUSION

Among patients with resected AoV carcinoma, the adjuvant chemotherapy group was not associated with a significant survival benefit compared to the observation group. However, on multivariate analysis adjusting for prognostic factors, adjuvant chemotherapy following surgery was an independent prognostic factor for DFS in patients with resected AoV carcinoma. Further studies are needed to investigate the effectiveness of adjuvant chemotherapy according to histologic phenotype.

Are Lymph Node Metastases Associated With Survival in Black Patients With Pancreatic Cancer?

INTRODUCTION

Despite aggressive surgical care and systemic therapy, patients with pancreatic ductal adenocarcinoma (PDAC) have a poor prognosis. Recent studies show that racial disparities in outcome also exist. We sought to investigate the association lymph node (LN) metastases had with survival between Black and White patients with PDAC after resection.

METHODS

Retrospective analysis of 226 PDAC patients who underwent resection at a single institution from 2010 to 2018 was performed with attention to LN metastasis and patient race. The number of patients who received chemotherapy was also evaluated.

RESULTS

One Hundred Seventy Five (77.4%) PDAC patients were White and 51 (22.6%) were Black. 130 (59.3%) patients had LN metastasis (LN+). LN+ and LN- groups were similar in race (P = 0.93), sex (P = 0.10) and age at the time of diagnosis (P = 0.45). Patients with LN + disease were more likely to present with larger tumors (3.4 versus 2.8 cm, P = 0.02) and higher T status (P = 0.001). White and Black patients had similar rates of LN metastasis (59% versus 58.8%, P = 1.0). The median survival for LN- Black and White patients were similar (43.2 versus 30.2 mo, P = 0.82). LN + Black patients trended towards receiving more systemic therapy than White LN + patients (55% versus 42%, P = 0.10). The median survival for LN + Black patients was significantly less than LN + White patients (17.5 versus 24.6 mo, P = 0.04).

CONCLUSIONS

Black LN + PDAC patients have an inferior survival rate after resection when compared to their White counterparts. Our disparity in outcome cannot be solely explained by a difference in systemic treatment. Further investigation is warranted to determine racial differences in tumor biology or response to chemotherapy.

Comparison of MRI and CT-based radiomics for preoperative prediction of lymph node metastasis in pancreatic ductal adenocarcinoma

Background

The preoperative prediction of lymph node metastasis (LNM) in pancreatic ductal adenocarcinoma (PDAC) is essential in prognosis and treatment strategy formulation.

Purpose

To compare the performance of computed tomography (CT) and magnetic resonance imaging (MRI) radiomics models for the preoperative prediction of LNM in PDAC.

Material and Methods

In total, 160 consecutive patients with PDAC were retrospectively included, who were divided into the training and validation sets (ratio of 8:2). Two radiologists evaluated LNM basing on morphological abnormalities. Radiomics features were extracted from T2-weighted imaging, T1-weighted imaging, and multiphase contrast enhanced MRI and multiphase CT, respectively. Overall, 1184 radiomics features were extracted from each volume of interest drawn. Only features with an intraclass correlation coefficient ≥0.75 were included. Three sequential feature selection steps—variance threshold, variance thresholding and least absolute shrinkage selection operator—were repeated 20 times with fivefold cross-validation in the training set. Two radiomics models based on multiphase CT and multiparametric MRI were built with the five most frequent features. Model performance was evaluated using the area under the curve (AUC) values.

Results

Multiparametric MRI radiomics model achieved improved AUCs (0.791 and 0.786 in the training and validation sets, respectively) than that of the CT radiomics model (0.672 and 0.655 in the training and validation sets, respectively) and of the radiologists’ assessment (0.600–0.613 and 0.560–0.587 in the training and validation sets, respectively).

Conclusion

Multiparametric MRI radiomics model may serve as a potential tool for preoperatively evaluating LNM in PDAC and had superior predictive performance to multiphase CT-based model and radiologists’ assessment.

Total Neoadjuvant Treatment for Pancreatic Ductal Adenocarcinoma Is Associated With Limited Lymph Node Yield but Improved Ratio

INTRODUCTION

The lymph node yield (LNY) and lymph node ratio (LNR) of nodal metastases following pancreatoduodenectomy (PD) have been reported as prognostic parameters in patients with pancreatic ductal adenocarcinoma (PDAC). However, they have not been compared in the setting of various neoadjuvant therapy modalities.

METHODS

A single institutional retrospective study identified 134 patients diagnosed with resectable, BLR- and LA-PDAC who underwent PD at Fox Chase Cancer Center between 2010 and 2019. Patients were categorized based on first-line treatment as follows: surgery first (SF), total neoadjuvant therapy (TNT), and single modality neoadjuvant therapy (SMNT). The histopathological reports of the surgical specimens were examined to obtain LNY and determine the counts of lymph nodes with metastases. Subsequently, LNR was calculated as the number of positive lymph nodes divided by the number of lymph nodes examined.

RESULTS

Overall, 49, 38, 27, 12, and 8 patients underwent SF approach, SMNT, incomplete TNT, induction TNT, and consolidation TNT, respectively. There was no difference in R0 resection and vascular resection between the groups (P = 0.096 and 0.794, respectively). The median counts of LNY were 22, 15, 21, 11.5, and 10, respectively (P < 0.001). The average LNR was 0.16, 0.07, 0.03, 0.02, and 0.02, respectively (P < 0.001). There were statistically significant differences in overall survival in the TNT groups (log-rank test P = 0.030).

CONCLUSIONS

PDAC patients who undergo the TNT modality exhibit lower LNY and improved LNR compared with the SF approach and SMNT neoadjuvant therapy groups. This is likely explained by the increased treatment response and lymph node obliteration associated with the TNT approach. Our results question the minimal requirement of 11-18 harvested lymph nodes for PD following TNT.

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.

Postoperative survival effect of the number of examined lymph nodes on esophageal squamous cell carcinoma with pathological stage T1–3N0M0

Background

The postoperative survival effect of the number of examined lymph nodes on patients of R0-resected esophageal squamous cell carcinoma with pathological stage T1–3N0M0 is still unclear.

Methods

Patients diagnosed with pathological stage T1–3N0M0 esophageal squamous cell carcinoma from two cancer databases—our cancer center (N = 707), and Surveillance Epidemiology and End Results (N = 151). The primary clinical endpoint was overall survival. The X-tile software was used to determine the optimal cutoff value of the number of examined lymph nodes, and propensity score matching was conducted to reduce selection bias according to the results of X-tile software. The cohort of 151 patients from another database was used for validation.

Results

X-tile software provided an optimal cutoff value of 15 examined lymph nodes based on 707 patients, and 231 pairs of matched patients were included. In the unmatched cohort, Cox proportional hazard regression analysis revealed better overall survival in patients with more than 15 examined lymph nodes (adjusted hazard ratio, 0.566, 95% confidence interval, 0.445–0.720; p < 0.001) compared with patients with 15 or fewer examined lymph nodes. In the validation cohort, patients with more than 15 examined lymph nodes also had better overall survival (adjusted hazard ratio 0.665, p = 0.047).

Conclusions

The number of examined lymph nodes is a significant prognostic factor in esophageal squamous cell carcinoma patients with pathological stage T1–3N0M0, and more than 15 examined lymph nodes are associated with better overall survival. Although the difference is not significant, the survival curve of patients with examined lymph nodes > 30 is better than those with examined lymph nodes 15–30. We believe that the number of examined lymph nodes can provide prognostic guidance for those patients, and the more examined lymph nodes cause lesser occult lymph nodes metastasis and lead to a better prognosis. Therefore, surgeons and pathologists should try to examine as many lymph nodes as possible to evaluate the pathological stage precisely. However, we need more validation from other studies.

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.

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.

A Novel Criterion for Lymph Nodes Dissection in Distal Pancreatectomy for Ductal Adenocarcinoma: A Population Study of the US SEER Database

OBJECTIVE

The aim of this study was to clarify the minimum number of examined lymph nodes (MNELNs) required to ensure the quality of lymph node detection and its impact on long-term survival in distal pancreatectomy for pancreatic ductal adenocarcinoma.

METHODS

Clinicopathological characteristics and survival data of patients with resectable pancreatic cancer who underwent distal pancreatectomy between 2004 and 2017 were collected from the Surveillance, Epidemiology, and End Results database. The associations between the number of examined lymph nodes (ELNs) and number of positive lymph nodes (PLNs), stage migration, and overall survival were investigated through adjusted multivariate models with locally weighted scatterplot smoothing smoothing fitting curves and estimation of the structural breakpoints. Kaplan-Meier survival analysis and X-tile software were used to identify the ideal cut-off value for ELNs.

RESULTS

In total, 2610 consecutive patients who underwent distal pancreatectomy between 2004 and 2017 were included in this study. The optimal ELN count according to the associations between the number of ELNs and number of PLNs, odds ratio for stage migration, or hazard ratio for overall survival were 19, 17, and 19, respectively. Furthermore, the optimal division of ELN count for maximum overall survival was divided into three populations (ELN ≤ 8, ELN 9-18, ELN ≥ 19) based on X-tile software.

CONCLUSION

A minimal count of 19 lymph nodes was demanded to guarantee the quality of lymph node examination in patients with distal pancreatectomy. Long-term survival could be delimited by MNELNs. A sufficient number of ELNs could improve the accuracy of cancer staging and reflect a better overall survival.

Clinical Impact of Unexpected Para-Aortic Lymph Node Metastasis in Surgery for Resectable Pancreatic Cancer

Radiologically identified para-aortic lymph node (PALN) metastasis is contraindicated for pancreatic cancer (PC) surgery. There is no clinical consensus for unexpected intraoperative PALN enlargement. To analyze the prognostic role of unexpected PALN enlargement in resectable PC, we retrospectively reviewed data of 1953 PC patients in a single tertiary center. Patients with unexpected intraoperative PALN enlargement (group A1, negative pathology, n = 59; group A2, positive pathology, n = 13) showed median overall survival (OS) of 24.6 (95% CI: 15.2-33.2) and 13.0 (95% CI: 4.9-19.7) months, respectively. Patients with radiological PALN metastasis without other metastases (group B, n = 91) showed median OS of 8.6 months (95% CI: 7.4-11.6). Compared with group A1, groups A2 and B had hazard ratios (HRs) of 2.79 (95% CI, 1.4-5.7) and 2.67 (95% CI: 1.8-4.0), respectively. Compared with group A2, group B had HR of 0.96 (95% CI: 0.5-1.9). Multivariable analysis also showed positive PALN as a negative prognostic factor (HR 2.57, 95% CI: 1.2-5.3), whereas positive regional lymph node did not (HR 1.32 95% CI: 0.8-2.3). Thus, unexpected malignant PALN has a negative prognostic impact comparable to radiological PALN metastasis. This results suggests prompt pathologic evaluation for unexpected PALN enlargements is needed and on-site modification of surgical strategy would be considered.

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.

Score for predicting overall survival in pancreatic adenocarcinoma patients with positive lymph nodes after surgery: a novel nomogram-based risk assessment

Background

Pancreatic adenocarcinoma (PaC) patients with positive lymph nodes (PLNs) have a dismal prognosis and lack a specific prognostic stage. This study aimed to construct a nomogram for the prediction of overall survival (OS) in these patients.

Methods

A total of 1,340 patients screened from the Surveillance, Epidemiology, and End Results database were included and randomly divided at a ratio of 7:3 into a training set (n=940) and an internal validation set (n=400). Cox regression analyses were conducted to select independent predictors in the training set, and a nomogram was constructed. The model was verified in the internal validation set and in an external validation set, which comprised 64 patients from a Chinese institute.

Results

Six independent prognostic factors (age at diagnosis, tumor grade, lymph node ratio, T stage, radiotherapy, and chemotherapy) were identified in PaC patients with PLNs and were entered into the nomogram. The final model had a higher C-index for predicting OS than the American Joint Committee on Cancer-8th edition staging system (training set: 0.658 vs. 0.546; internal validation set: 0.661 vs. 0.546; external validation set: 0.691 vs. 0.581). The 1-, 2-, and 3-year area under the receiver operating characteristic curve values indicated better discrimination power for the established nomogram with respect to the prediction of OS in the training, internal validation, and external validation sets than for the American Joint Committee on Cancer-8th edition staging system. Furthermore, the nomogram performed well in both calibration and decision curve analyses (DCA) of clinical applicability. OS in PaC patients with PLNs was significantly distinguished among the three risk groups stratified according to the nomogram score (P<0.001).

Conclusions

The well-calibrated nomogram was determined to be extremely efficient in predicting survival, and defining a high-risk population based on the nomogram score among PaC patients with PLNs after surgery.

Clinical Implication of Node-negative Resectable Pancreatic Cancer

BACKGROUND

Lymph node metastasis is one of the strongest prognostic factors of pancreatic cancer. However, the clinical implication of pathologically node-negative pancreatic cancer (pN0-PC) has not been fully investigated.

METHODS

Patients who underwent surgical resection for radiologically resectable pancreatic cancer between 2002 and 2018 were included in this study. A clinicopathological examination focusing on pN0-PC was performed.

RESULTS

Of all 533 patients, 155 (29.1%) were diagnosed with pN0-PC and 378 (70.9%) were diagnosed with node-positive pancreatic cancer (pN1/2-PC). The 5-year survival rates of patients with pN0-PC and pN1/2-PC were 57.1% and 25.0%, respectively (p < 0.001). A multivariate analysis revealed six prognostic factors in pN0-PC: age ≥ 70 years, nonadministration of adjuvant chemotherapy, anterior serosal invasion, nerve plexus invasion, and microscopic lymphatic and venous invasions. The 5-year survival rates of patients who had pN0-PC with 0-1 risk factor, with 2-3 risk factors, and with 4-6 risk factors were 87.6%, 47.9%, and 16.4%, respectively. Survival of patients who had pN0-PC with 4-6 risk factors was comparable to that of pN1/2 patients. The diagnostic capability of metastasis-negative lymph node was unsatisfactory, with a predictive value of < 43%.

CONCLUSIONS

Although the prognosis of patients with pN0-PC was better than that of patients with pN1/2-PC, it is not satisfactory. Survival of patients who had pN0-PC with 0-1 risk factors was extremely favorable; however, survival of patients who had pN0-PC with 4-6 risk factors was similar to those with pN1/2-PC.

A nomogram of preoperative predictors for occult metastasis in patients with PDAC during laparoscopic exploration

Background

Surgical resection is the only potentially curative treatment for pancreatic ductal adenocarcinoma (PDAC). However, most of patients lose the chance of surgery due to the unresectable disease at the time of diagnosis. Despite the improvement of radiological imaging, a portion of patients intended for radical resection were proven to be unresectable at surgical exploration due to occult metastasis.

Methods

Patients who were aimed to undergo radical pancreatectomy for PDAC from 2010 to 2019 were reviewed retrospectively. All patients included underwent diagnostic laparoscopic exploration. Patients were divided into two groups depending on whether distant metastasis were encountered during exploration. Univariate and multivariate logistic regression analyses were used to identify risk factors for occult metastasis. A nomogram to predict occult metastasis of PDAC on exploration was developed and evaluated.

Results

A total of 273 patients who underwent diagnostic laparoscopic exploration were included in this study. Nineteen (7.0%) patients were found with distant metastasis during exploration. Multivariate logistic regression analysis showed that ALT>40U/L, CA19-9, CA125 and regional nodes enlargement were independent predictors for occult metastasis. Incorporating these four factors, the nomogram achieved concordance index of 0.799, with a well-fitted calibration curve.

Conclusions

Occult metastasis is not unusual during surgical exploration in patients with resectable or borderline resectable PDAC. The nomogram could achieve a personal prediction of unexpected distant metastasis on exploration. It may help to sift through patients with PDAC who would benefit from laparoscopic exploration.

Unexpected Para-aortic Lymph Node Metastasis in Pancreatic Ductal Adenocarcinoma: a Contraindication to Resection?

BACKGROUND

Margin-negative resection is the only cure for pancreatic cancer. However, para-aortic lymph node metastasis is considered a contraindication to curative resection in pancreatic cancer. To determine if there are long-term survival differences according to the presence or absence of para-aortic lymph node metastasis in patients undergoing pancreatectomy, we evaluated oncologic outcomes in resected pancreatic cancer with unexpected para-aortic lymph node metastasis confirmed on intraoperative frozen section biopsy.

METHODS

We retrospectively investigated 362 patients with pathologically confirmed pancreatic ductal adenocarcinoma who underwent pancreatectomy between 1996 and 2016.

RESULTS

Patients with a metastatic para-aortic lymph node had the poorest median disease-specific survival [hazard ratio 14, 95% confidence interval 10-19]. However, after chemotherapy, patients with a metastatic para-aortic lymph node had a much higher disease-specific survival rate (para-aortic lymph node+/postoperative chemotherapy- versus para-aortic lymph node+/postoperative chemotherapy+, P = 0.0003, adjusted P = 0.0015). Patients with a metastatic para-aortic lymph node who underwent postoperative chemotherapy had a similar survival benefit to patients with metastatic regional lymph node without para-aortic lymph node metastasis, regardless of postoperative chemotherapy (para-aortic lymph node+/postoperative chemotherapy+ versus regional lymph node+/postoperative chemotherapy-, P = 0.3047, adjusted P > 0.9999; para-aortic lymph node+/postoperative chemotherapy+ versus regional lymph node+/postoperative chemotherapy+, P = 0.0905, adjusted P = 0.4525).

CONCLUSIONS

Unexpected para-aortic lymph node metastasis on frozen section biopsy may no longer be a contraindication to curative resection in "resectable" pancreatic ductal adenocarcinoma, as long as postoperative adjuvant chemotherapy can be administered.

Pancreatic body and tail cancer and favorable metastatic lymph node behavior on the left edge of the aorta

BACKGROUND

Lymph node (LN) metastasis in pancreatic body-tail cancer is a poor prognostic factor and the optimal LN dissection area for distal pancreatectomy (DP) remains unclear. Lymphatic flow from the tumors is thought to depend on the tumor sites. We examined LN metastasis frequency based on tumor site and recurrent patterns post-DP.

METHODS

With a retrospective, single institutional study, we examined 100 patients who underwent DP as an upfront surgery for pancreatic cancer over 17 years. Tumor sites were classified as tumor confined to pancreatic body (and neck) (Pb(n)); and pancreatic tail (Pt). We compared metastatic LN and recurrence patterns based on tumor site. The median overall survival (OS) and disease-free survival (DFS) were analyzed.

RESULTS

LN metastasis occurred in 59/100 (59.0%), with 23 and 25 tumors located in the Pb(n), and Pt, respectively. Those with the tumor in Pt had metastases to #10, #11d/p, and #18 LN mainly. However, the patients with the Pb(n) tumor had metastases to #8a/p, #11p, and #14p/d LN. There was no metastasis to #10 and #11d LN. The OS and DFS were 34 and 15 months, respectively. No significant difference was found in the OS, DFS, and recurrence patterns based on tumor sites.

CONCLUSION

Differences in metastatic LN sites were observed in pancreatic body-tail cancer when tumors were confined to the left or right of the left aortic edge. Although it is necessary to validate this finding with a large-scale study, organ-preserving DP might be a treatment option for selected patients depending on the tumor sites.

Impact of examined lymph node count on prognosis in patients with lymph node-negative pancreatic body/tail ductal adenocarcinoma

Background

Because the overall prognosis remains dismal for patients with resected pancreatic cancer (PC), we aimed to explore the prognostic impact of examined lymph node (ELN) count on lymph node (LN)-negative pancreatic body/tail ductal adenocarcinoma.

Methods

Patients' data were extracted from the Surveillance, Epidemiology, and End Results (SEER) database (National Cancer Institute, USA) to investigate the relationship between ELN count and survival outcomes of LN-negative pancreatic body/tail ductal adenocarcinoma.

Results

A total of 700 patients were included, and the median number of ELNs was 11. The respective 1-, 3-, 5-year overall survival (OS) rates were 75.3%, 37.7%, 30.3%, and the 1-, 3-, 5-year cancer-specific survival (CSS) were 78.3%, 41.7%, 34.5%. The X-tile analysis showed that 14 was the most optimal cutoff for both OS and CSS. Kaplan-Meier survival analysis indicated that patients with ELNs >14 had better OS and CSS than ELNs ≤14. Multivariate Cox analysis showed ELNs ≤14 was an independent risk factor for both OS [hazard ratio (HR), 1.357; 95% confidence interval (CI), 1.080-1.704; P=0.009] and CSS (HR, 1.394; 95% CI, 1.092-1.778; P=0.008).

Conclusions

ELN count is associated with the survival rate in patients with LN-negative pancreatic body/tail ductal adenocarcinoma. Accurate nodal staging for these patients requires more than 14 ELNs.

Role of lymphadenectomy in resectable pancreatic cancer

BACKGROUND

Pancreatic cancer (PC) remains one of the most devastating malignant diseases, predicted to become the second leading cause of cancer-related death by 2030. Despite advances in surgical techniques and in systemic therapy, the 5-year relative survival remains a grim 9% for all stages combined. The extent of lymphadenectomy has been discussed intensively for decades, given that even in early stages of PC, lymph node (LN) metastasis can be detected in approximately 80%.

PURPOSE

The primary objective of this review was to provide an overview of the current literature evaluating the role of lymphadenectomy in resected PC. For this, we evaluated randomized controlled studies (RCTs) assessing the impact of extent of lymphadenectomy on OS and studies evaluating the prognostic impact of anatomical site of LN metastasis and the impact of the number of resected LNs on OS.

CONCLUSIONS

Lymphadenectomy plays an essential part in the multimodal treatment algorithm of PC and is an additional therapeutic tool to increase the chance for surgical radicality and to ensure correct staging for optimal oncological therapy. Based on the literature from the last decades, standard lymphadenectomy with resection of at least ≥ 15 LNs is associated with an acceptable postoperative complication risk and should be recommended to obtain local radicality and accurate staging of the disease. Although radical surgery including appropriate lymphadenectomy of regional LNs remains the only chance for long-term tumor control, future studies specifically assessing the impact of neoadjuvant therapy on extraregional LNs are warranted.

A Radiomics Nomogram for the Preoperative Prediction of Lymph Node Metastasis in Pancreatic Ductal Adenocarcinoma

PURPOSE

To construct and verify a CT-based multidimensional nomogram for the evaluation of lymph node (LN) status in pancreatic ductal adenocarcinoma (PDAC).

MATERIALS AND METHODS

We retrospectively assessed data from 172 patients with clinicopathologically confirmed PDAC surgically resected between February 2014 and November 2016. Patients were assigned to either a training cohort (n = 121) or a validation cohort (n = 51). We acquired radiomics features from the preoperative venous phase (VP) CT images. The maximum relevance-minimum redundancy (mRMR) algorithm and the least absolute shrinkage and selection operator (LASSO) methods were used to select the optimal features. We used multivariable logistic regression to construct a combined radiomics model for visualization in the form of a nomogram. Performance of the nomogram was evaluated by the receiver operating characteristic (ROC) curve approach, calibration testing, and analysis of clinical usefulness.

RESULTS

A Rad score consisting of 10 LN status-related radiomics features was found to be significantly associated with the actual LN status (P < 0.01). A nomogram that consisted of Rad scores, CT-reported parenchymal atrophy, and CT-reported LN status performed well in terms of predictive power in the training cohort (area under the curve, 0.92), and this was confirmed in the validation cohort (area under the curve, 0.95). The nomogram also performed well in the calibration test and decision curve analysis, demonstrating its potential clinical value.

CONCLUSION

A multidimensional radiomics nomogram consisting of Rad scores, CT-reported parenchymal atrophy, and CT-reported LN status may contribute to the non-invasive evaluation of LN status in PDAC patients.

Improved oncologic outcomes for minimally invasive left pancreatectomy: Propensity-score matched analysis of the National Cancer Database

BACKGROUND AND OBJECTIVES

Minimally invasive (MIS) left pancreatectomy (LP) is increasingly used to treat pancreatic adenocarcinoma (PDAC). Despite improved short-term outcomes, no studies have demonstrated long-term benefits over open resection.

METHODS

The National Cancer Database was queried between 2010 and 2016 for patients with PDAC, grouped by surgical approach (MIS vs open). Demographics, comorbidities, clinical staging, and pathologic staging were used for propensity-score matching. Perioperative, short-term oncologic, and survival outcomes were compared.

RESULTS

After matching, both cohorts included 805 patients. There were no differences in baseline characteristics, staging, or preoperative therapy between cohorts. The MIS cohort had a shorter length of stay (6.8 ± 5.5 vs 8.5 ± 7.3 days; P < .0001) with the trend toward improved time to chemotherapy (53.9 ± 26.1 vs 57.9 ± 29.9 days; P = .0511) and margin-positive resection rate (15.3% vs 18.9%; P = .0605). Lymph node retrieval and receipt of chemotherapy were similar. The MIS cohort had higher median overall survival (28.0 vs 22.1 months; P = .0067). Subgroup analysis demonstrated the highest survival for robotic compared with laparoscopic and open LP (41.9 vs 26.6 vs 22.1 months; P < .0001).

CONCLUSIONS

This study demonstrates the safety of MIS LP and favorable long-term oncologic outcomes. The improved survival after MIS LP warrants further study with prospective, randomized trials.

Development of a MUC16-Targeted Near-Infrared Fluorescent Antibody Conjugate for Intraoperative Imaging of Pancreatic Cancer

Surgical resection is currently the only potentially curative option for patients with pancreatic cancer. However, the 5-year survival rate after resection is only 25%, due in part to high rates of R1 resections, in which cells are left behind at the surgical margin, resulting in disease recurrence. Fluorescence-guided surgery (FGS) has emerged as a method to reduce incomplete resections and improve intraoperative assessment of cancer. Mucin-16 (MUC16), a protein biomarker highly overexpressed in pancreatic cancer, is a potential target for FGS. In this study, we developed a fluorescent MUC16-targeted antibody probe, AR9.6-IRDye800, for image-guided resection of pancreatic cancer. We demonstrated the efficacy of this probe to bind human pancreatic cancer cell lines in vitro and in vivo In an orthotopic xenograft model, AR9.6-IRDye800 exhibited superior fluorescence enhancement of tumors and lower signal in critical background organs in comparison to a nonspecific IgG control. The results of this study suggest that AR9.6-IRDye800 has potential for success as a probe for FGS in pancreatic cancer patients, and MUC16 is a feasible target for intraoperative imaging.

Score for the Overall Survival Probability of Patients With Pancreatic Adenocarcinoma of the Body and Tail After Surgery: A Novel Nomogram-Based Risk Assessment

Pancreatic adenocarcinoma of the body and tail often has a dismal prognosis and lacks a specific prognostic stage. The aim of this study was to construct a nomogram for predicting survival of patients with pancreatic adenocarcinoma of the body and tail after surgery. Data of patients were selected from the Surveillance, Epidemiology, and End Results (SEER) database and from medical records of Sun Yat-sen University Cancer Center (SYSUCC). In a multivariate analysis for overall survival (OS), the following six variables were identified as independent predictors and incorporated into the nomogram: age, tumor differentiation, tumor size, lymph node ratio (LNR), and chemotherapy. A nomogram was built based on independent risk predictors. The concordance index (C-index) for nomogram, Tumor-Node-Metastasis (TNM) 7th and 8th stage system were 0.775 [95% confidence interval (CI), 0.731–0.819], 0.617 (95%CI, 0.575–0.659), and 0.632 (95%CI, 0.588–0.676), respectively. The calibrated nomogram predicted survival rates which closely corresponded to the actual survival rates. Furthermore, the values of the area under receiver operating characteristic (ROC) curves (AUC) of the nomograms were higher than those of the TNM 7th or 8th stage system in predicting 1-, 2-, and 3-year survival of patients in training and external validation cohorts. The well-calibrated nomogram could be used to predict prognosis for patients with pancreatic adenocarcinoma of the body and tail after surgery.

Reappraisal of nodal staging and study of lymph node station involvement in distal pancreatectomy for body-tail pancreatic ductal adenocarcinoma

BACKGROUND

The pattern of nodal spread in body-tail pancreatic ductal adenocarcinoma (PDAC) has been poorly investigated. This study analyzed the characteristics of lymph node (LN) involvement and the prognostic role of nodal metastases stratified by LN stations.

METHODS

All upfront distal pancreatectomies (DPs) for PDAC (2000-2017) with complete information on station 8,10,11, and 18 were included. Clinico-pathological correlates and survival were investigated using uni- and multivariable analyses.

RESULTS

Among 100 included patients, 28 were N0, 42 N1 and 30 N2. The median number of examined LN was 32 (IQR 26-44). Tumor size at preoperative imaging increased across N-classes. Preoperative size >27.5 mm was associated with N2 status. The frequency of nodal metastases at stations 8, 9, 10, 11, and 18 was 12.0%, 10.9%, 3.0%, 71.0%, and 19%, respectively. The pattern of LN spread was independent from primary tumor location (with tail tumors metastasizing to station 8/9 and body tumors to station 10), while it was highly associated with N-class. At multivariable analysis, tumor grading, adjuvant treatment, station 9 and 10 metastases were independent prognostic factors in node-positive patients.

CONCLUSIONS

In patients undergoing upfront DP for PDAC preoperative tumor size is associated with the degree of nodal spread. While station 11 was the most frequently involved, only station-9 and 10 metastases were independent prognostic factors. The site of nodal metastases was somewhat unpredictable based on tumor location. This data has potential implications for allocating patients to neoadjuvant treatment and supports the performance of routine splenectomy during DP for PDAC.

The Value of Total Lymph Nodes Examined and Number of Positive Lymph Nodes in Determining the Role of Adjuvant Radiation in Pancreatic Cancer Patients

OBJECTIVES

The aim of this study was to determine the survival benefits by adjuvant radiation therapy (RT) in pancreatic cancer patients with different total lymph nodes examined (TNE), number of positive lymph nodes (NPN), and lymph nodes ratio (LNR).

METHODS

National Cancer Database was queried for nonmetastatic pancreatic cancer patients from 2004 to 2015. Cox models were utilized. Interaction terms were applied to evaluate the effect of RT in different NPN, LNR, and margin strata. Multivariate analysis was performed.

RESULTS

Of 19,759 patients identified, 10,910 patients qualified. Compared with TNE of 1 to 9, TNE of 10 to 14, 15 to 19, 20 to 24, and 25 or greater had progressive overall survival (OS) benefits. Adjuvant RT had similar OS benefits among them. In negative margin patients, adjuvant RT improved OS when NPN was 2 to 3 (hazards ratio [HR], 0.84; P = 0.01) or LNR was 0.15 to 0.25 (HR, 0.79; P = 0.002). In positive margin patients, adjuvant RT nonsignificantly improved OS when NPN was 1 to 3 (HR, 0.89; P = 0.36) or when NPN was 4 or greater (HR, 0.79; P = 0.07).

CONCLUSIONS

Higher TNE correlates with better survival. Adjuvant RT may not compensate for inadequate lymph node dissection. Adjuvant RT improves survival in negative-margin patients with 2 to 3 positive lymph nodes or LNR of 0.15 to 0.25.

Resectable pancreatic ductal adenocarcinoma: association between preoperative CT texture features and metastatic nodal involvement

Background

To explore the relationship between the lymph node status and preoperative computed tomography images texture features in pancreatic cancer.

Methods

A total of 155 operable pancreatic cancer patients (104 men, 51 women; mean age 63.8 ± 9.6 years), who had undergone contrast-enhanced computed tomography in the arterial and portal venous phases, were enrolled in this retrospective study. There were 73 patients with lymph node metastases and 82 patients without nodal involvement. Four different data sets, with thin (1.25 mm) and thick (5 mm) slices (at arterial phase and portal venous phase) were analysed. Texture analysis was performed by using MaZda software. A combination of feature selection algorithms was used to determine 30 texture features with the optimal discriminative performance for differentiation between lymph node positive and negative groups. The prediction performance of the selected feature was evaluated by receiver operating characteristic (ROC) curve analysis.

Results

There were 10 texture features with significant differences between two groups and significance in ROC analysis were identified. They were WavEnLH_s-2(wavelet energy with rows and columns are filtered with low pass and high pass frequency bands with scale factors 2) from wavelet-based features, 135dr_LngREmph (long run emphasis in 135 direction) and 135dr_Fraction (fraction of image in runs in 135 direction) from run length matrix-based features, and seven variables of sum average from coocurrence matrix-based features (SumAverg). The ideal cutoff value for predicting lymph node metastases was 270 for WavEnLH_s-2 (positive likelihood ratio 2.08). In addition, 135dr_LngREmph and 135dr_Fraction were correlated with the ratio of metastatic to examined lymph nodes.

Conclusions

Preoperative computed tomography high order texture features provide a useful imaging signature for the prediction of nodal involvement in pancreatic cancer.

Prognostic impact of lymph node status in patients after total pancreatectomy for pancreatic ductal adenocarcinoma: A strobe-compliant study

The optimal number of examined lymph nodes (ELN) for staging and impact of nodal status on survival following total pancreatectomy (TP) for pancreatic ductal adenocarcinoma (PDAC) is unclear. The aim of this study was to evaluate the prognostic impact of different lymph node status after TP for PDAC.The Surveillance, Epidemiology, and End Results (SEER) database was used to identify patients who underwent TP for PDAC from 2004 to 2015. We calculated overall survival (OS) of these patients using Kaplan-Meier analysis and Cox proportional hazards model.Overall, 1291 patients were included in the study, with 869 node-positive patients (49.5%). A cut-off points analysis revealed that 19, 19, and 13 lymph nodes best discriminated OS for all patients, node-negative patients, and node-positive patients, respectively. Higher number of ELN than the corresponding cut-off points was an independent predictor for better prognosis [all patients: hazard ratios (HR) 0.786, P = .002; node-negative patients: HR 0.714, P = .043; node-positive patients: HR 0.678, P < .001]. For node-positive patients, 1 to 3 positive lymph nodes (PLN) correlated independently with better survival compared with those with 4 or more PLN (HR 1.433, P = .002). Moreover, when analyzed in node-positive patients with less than 13 ELN, neither the number of PLN nor lymph node ratio (LNR) was associated with survival. However, when limited node-positive patients with at least 13 ELN, univariate analyses showed that both the number of PLN and LNR were associated with survival, whereas multivariate analyses demonstrated that only number of PLN was consistently associated with survival (HR 1.556, P = .004).Evaluation at least 19 lymph nodes should be considered as quality metric of surgery in patients who underwent TP for PDAC. For node-negative patients, a minimal number of 19 lymph nodes is adequate to avoid stage migration. For node-positive patients, PLN is superior to LNR in predicting survival after TP, predominantly for those with high number of ELN.

International consensus statement on robotic pancreatic surgery

The robotic surgical system has been applied to various types of pancreatic surgery. However, controversies exist regarding a variety of factors including the safety, feasibility, efficacy, and cost-effectiveness of robotic surgery. This study aimed to evaluate the current status of robotic pancreatic surgery and put forth experts' consensus and recommendations to promote its development. Based on the WHO Handbook for Guideline Development, a Consensus Steering Group* and a Consensus Development Group were established to determine the topics, prepare evidence-based documents, and generate recommendations. The GRADE Grid method and Delphi vote were used to formulate the recommendations. A total of 19 topics were analyzed. The first 16 recommendations were generated by GRADE using an evidence-based method (EBM) and focused on the safety, feasibility, indication, techniques, certification of the robotic surgeon, and cost-effectiveness of robotic pancreatic surgery. The remaining three recommendations were based on literature review and expert panel opinion due to insufficient EBM results. Since the current amount of evidence was low/meager as evaluated by the GRADE method, further randomized controlled trials (RCTs) are needed in the future to validate these recommendations.

Overall survival in patients over 40 years old with surgically resected pancreatic carcinoma: a SEER-based nomogram analysis

BACKGROUND

The aim of this study was to identify the determinants of overall survival (OS) within patients over 40 years old with surgically resected pancreatic carcinoma (PC), and to develop a nomogram with the intention of OS predicting.

METHODS

A total of 6341 patients of 40 years of age or later with surgically resected PC between 2010 and 2015 were enrolled from the Surveillance, Epidemiology, and End Results (SEER) program and randomly assigned into training set (4242 cases) and validation set (2099 cases). A nomogram was constructed for predicting 1-, 2- and 3-years OS based on univairate and multivariate Cox regression. The C-index and calibration plot were adopted to assess the nomogram performance.

RESULTS

Our analysis showed that age, location of carcinoma in pancreas, tumor grade, TNM stage, size of carcinoma together with lymph node ratio (LNR) were considered to be independent overall survival predictors. A nomogram based on these six factors was developed with C-index being 0.680 (95%CI: 0.667-0.693). All calibration curves of OS fitted well. The OS curves stratified by nomogram-predicted probability score (≥20, 10-19 and < 10) demonstrated statistically significant difference not only within training set but also in validation set.

CONCLUSIONS

The present nomogram for OS predicting can serve as the efficacious survival-predicting model and assist in accurate decision-making for patients over 40 years old with surgically resected PC.

Underutilization of Surgery in Periampullary Cancer Treatment

BACKGROUND

Site-specific outcomes of resection for periampullary cancer have not been analyzed on a large, registry-based scale.

METHODS

We assessed data on periampullary cancers from the SEER database. Site- and stage-specific outcomes were analyzed. Resection was compared to no resection.

RESULTS

Resection was the main therapy in stages 1 and 2 (resection vs. no resection, 8644 vs. 7208 patients), was less frequent in stage 3 (1248 vs. 2783 patients) and was rarely-but still-used in stage 4 disease (541 vs. 11,212 patients). Pancreatic head (75.7%), 11.4% distal bile duct, 7.7% ampullary, and 5.3% duodenal cancers. Cancer subtype-independent median survival was 22.0 (resection) vs. 7.0 months (no resection) in stages 1 and 2, 21.0 vs. 8.0 months in stage 3, and 10.0 vs. 3.0 months in stage 4. Subtype-dependent median survival (resection vs. no resection) was 18.0 vs. 5.0 months in pancreatic head, 19.0 vs 4.0 months in distal bile duct, 41.0 vs 7.0 months in ampullary, and 38.0 vs 4.0 months in duodenal adenocarcinoma. On multivariable analysis, patient comorbidities, marital and insurance status, and income all influenced the decision to undergo resection.

CONCLUSIONS

Surgery is still underutilized in the treatment of periampullary cancers. Patients with cancers originating from the duodenum or the ampulla of Vater benefit most from resectional surgery.

Predictors of nodal metastasis and prognostic significance of lymph node ratio and total lymph node count in tracheobronchial adenoid cystic carcinoma

Purpose

To identify potential risk factors of lymph node metastasis and to verify the prognostic significance of the lymph node ratio (LNR) and the total number of lymph nodes examined (NNE) in tracheobronchial adenoid cystic carcinoma (ACC) patients, using a large population-based database.

Patients and methods

From Surveillance, Epidemiology, and End Results database, we identified 263 patients with tracheobronchial ACC in whom complete lymph node data could be obtained. Logistic regression analysis was performed to determine predictive factors of nodal metastasis. X-tile software determined the optimal cut-off points for LNR and NNE. Kaplan- Meier analyses and Cox regression models were adopted for survival analysis.

Results

Of 263 patients, 75 (28.5%) had lymph node involvement. Tumors of bronchial origin (P<0.001) and tumors larger than 30 mm (P<0.001) were associated with a higher likelihood of nodal involvement. Examination of more than ten lymph nodes could avoid understaging and resulted in improved survival; meanwhile, patients with a LNR of 0.07 or less had favorable prognosis.

Conclusion

Patients with tracheobronchial ACC have significant risk of lymph node metastasis. Bronchial ACC and larger tumor size are both risk factors of lymph node metastasis. LNR and NNE may provide a more precise prediction of survival and could be taken into account in future clinical work.

Overall survival and cancer-specific survival in patients with surgically resected pancreatic head adenocarcinoma: A competing risk nomogram analysis

Background: The objective of this study was to estimate probabilities of overall survival (OS) and cancer-specific survival (CSS) in patients with pancreatic head adenocarcinoma after surgery. In addition, we attempted to build nomograms to predict prognosis of these patients.

Methods: Patients diagnosed with surgically resected pancreatic head adenocarcinoma between 2004 and 2014 were selected for the study from the Surveillance, Epidemiology, and End Results (SEER) database. Nomograms were established for estimating 1-, 2- and 3-year OS and CSS based on Cox regression model and Fine and Grey's model. The performance of the nomogram was measured by concordance index (C-index) and the area under receiver operating characteristic (ROC) curve (AUC).

Results: A total of 2374 patients were retrospectively collected from the SEER database. The discrimination of nomogram for OS prediction was superior to that of the Tumor-Node-Metastasis (TNM) 7th or 8th edition stage systems (C-index = 0.640, 95% CI, 0.618 - 0.662 vs 0.573, 95% CI, 0.554 - 0.593, P < 0.001; 0.640, 95% CI, 0.618 - 0.662 vs 0.596, 95% CI, 0.586 - 0.607, P < 0.001, respectively). The comparisons of values of AUC showed that the established nomograms displayed better discrimination power than TNM 7th or 8th stage systems for predicting both OS and CSS.

Conclusions: The nomograms which could predict 1-, 2- and 3-year OS and CSS were established in this study. Our nomograms showed a relatively good performance and could be served as an effective tool for prognostic evaluation of patients with pancreatic head adenocarcinoma after surgery.

Negative Lymph Node Count and Lymph Node Ratio Are Associated With Survival in Male Breast Cancer

BACKGROUND

Male breast cancer (MBC) is usually diagnosed at late stages and therefore has a worse prognosis than female breast cancer (FBC). MBC is also more likely to have lymph node (LN) involvement than FBC.

MATERIALS AND METHODS

We sought to determine the prognostic role of the examined lymph node (LN), negative LN (NLN), and positive LN counts and the LN ratio (LNR), defined as (positive LNs/ENLs), on the survival rate among MBC patients. We performed a large population-based study using the data from the Surveillance, Epidemiology, and End Results program.

RESULTS

Older age, black race, stage IV disease, ≤ 1 NLN, and a > 31.3% LNR were significantly associated with worse survival across all prediction models. Moreover, we demonstrated a decreased risk of mortality in MBC patients across the MBC-specific survival model (hazard ratio, 0.98; 95% confidence interval, 0.96-0.998; P = .03) and 10-year MBC-specific survival model (hazard ratio, 0.98; 95% confidence interval, 0.96-0.999; P = .04).

CONCLUSION

MBC has had an augmented incidence over the years. We found several independent predictors of MBC survival, including age, race, stage, NLNs, and the LNR. We strongly suggest adding the NLN count and/or LNR into the current staging system. Further studies are needed to provide information on the mechanisms underlying the association between the NLN count and MBC survival and the LNR and MBC survival.

Do patients benefit more from robot assisted approach than conventional laparoscopic distal pancreatectomy? A meta-analysis of perioperative and economic outcomes

BACKGROUND/PURPOSE

Robotic approach has improved the ergonomics of conventional laparoscopic distal pancreatectomy (LDP), but whether patients benefit more from robot assisted distal pancreatectomy (RADP) is still controversial. This meta-analysis aims to compare the perioperative and economic outcomes of RADP with LDP.

METHODS

A systematic review of the literature was carried out on PubMed, EMBASE, and the Cochrane Library between January 1990 and March 2017. All eligible studies comparing RADP versus LDP were included. Perioperative and economic outcomes constituted the end points.

RESULTS

13 English studies with 1396 patients were included. Regarding to intraoperative outcomes, RADP was associated with a significant decrease in conversion rate (OR = 0.52; 95%CI: 0.34, 0.78; P = 0.002). Although the spleen-preserving rates were comparable between RADP and LDP, a significant higher splenic vessels conservation rate was observed in the RADP group (OR = 4.71; 95%CI: 1.77, 12.56; P = 0.002). No statistically significant differences were found at operation time, estimated blood loss and blood transfusion rate. Concerning postoperative outcomes, pooled data indicated the overall morbidity, pancreatic fistula and the length of hospital stay did not differ significantly between the RADP and LDP groups. And concerning pathological outcomes, positive margin rate and the number of lymph nodules harvested were comparable between the two groups. The operative cost of RADP was almost double that of LDP (WMD = 2350.2 US dollars; 95%CI: 1165.62, 3534.78; P = 0.0001).

CONCLUSION

RADP showed a slight technical advantage. But whether this benefit is worth twofold cost should be considered by patient's individuation.

How to Reliably Assess Nodal Status in Distal Pancreatectomy for Adenocarcinoma

OBJECTIVES

The optimal number of lymph nodes that need to be analyzed to reliably assess nodal status in distal pancreatectomy for adenocarcinoma is still unknown.

METHODS

Two hundred seventy-eight patients who underwent distal pancreatectomy for adenocarcinoma were retrieved from a retrospective French nationwide database. The relations between the number of analyzed lymph nodes and the nodal status of the tumor were studied. The beta-binomial law was used to estimate the probability of being truly node negative depending on the number of analyzed lymph nodes. Cox proportional hazard model was used for the survival analysis.

RESULTS

The median number of analyzed lymph nodes was 15. There was a positive correlation between the number of positive lymph nodes and the number of lymph nodes analyzed. The curve reached a plateau at approximately 25 lymph nodes. The beta binomial model demonstrated that an analysis of 21 negative lymph nodes shows a probability to be truly N0 at 95%. N+ status was associated with survival, but the number of lymph node analyzed was not.

CONCLUSION

At least 21 lymph nodes should be analyzed to ensure a reliable assessment of the nodal status, but this number may be hard to reach in distal pancreatectomy.

Comparison of prognostic prediction between nomogram based on lymph node ratio and AJCC 8th staging system for patients with resected pancreatic head carcinoma: a SEER analysis

Background

The prognosis of pancreatic carcinoma (PC) remains poor and the American Joint Committee on Cancer (AJCC) 8th staging system for survival prediction in PC patients after curative resection is still limited. Thus, the aim of this study is to refine a valuable prognostic model and novel staging system for PC with curative resection.

Methods

The data of 3,458 patients used in this study were retrieved from the Surveillance, Epidemiology, and End Results database registry of National Cancer Institute. The prognostic value of lymph node ratio (LNR) was analyzed in the primary cohort and prognostic nomogram based on the LNR was established to create a novel staging system. Then, analyses were conducted to evaluate the application of the formulated nomogram staging system and the AJCC 8th staging system. The predictive performance of model was further validated in the internal validation cohort.

Results

Significant positive correlations were found between LNR and all factors except for surgical procedures. The results of univariate and multivariate analyses showed that LNR was identified as an independent prognostic indicator for overall survival (OS) in both primary and validation cohorts (all P < 0.001). A prognostic nomogram based on the LNR was formulated to obtain superior discriminatory abilities. Compared with the AJCC 8th staging system, the formulated nomogram staging system showed higher hazard ratios of stage II, III, and IV disease (reference to stage I disease) that were 1.637, 2.300, and 3.521, respectively, by univariate analyses in the primary cohort and the distinction between stage I, II, and III disease at the beginning or end of the survival curves was more apparent. All these results were further verified in the validation cohort.

Conclusion

LNR can be considered as a useful independent prognostic indicator for PC patients after curative resection regardless of the surgical procedures. Compared with the AJCC 8th staging system, the formulated nomogram showed superior predictive accuracy for OS and its novel staging system revealed better risk stratification.

Prognostic role of nodal ratio, LODDS, pN in patients with pancreatic cancer with venous involvement

Background

The UICC/AJCC TNM staging system classifies lymph nodes as N0 and N1 in pancreatic cancer. Aim of the study is to determine whether the number of examine nodes, the nodal ratio (NR) and the logarithm odds of positive lymph nodes (LODDS) may better stratify the prognosis of patients undergoing pancreatectomy combined with venous resection for pancreatic cancer with venous involvement.

Methods

A multicenter database of 303 patients undergoing pancreatectomy in 9 Italian referral centers was analyzed. The prognostic impact of number of retrieved and examined nodes, NR, LODDS was analyzed and compared with ROC curves analysis, Pearson test, univariate and multivariate analysis.

Results

The number of metastatic nodes, pN, the NR and LODDS was significantly correlated with survival at multivariate analyses. The corresponding AUC for the number of metastatic nodes, pN, the NR and LODDS were 0.66, 0.69, 0.63 and 0.65, respectively. The Pearson test showed a significant correlation between the number of retrieved lymph nodes and number of metastatic nodes, pN and the NR. LODDS had the lower coefficient correlation. Concerning N1 patients, the NR, the LODDS and the number of metastatic nodes were able to significantly further stratify survival (p = 0.040; p = 0.046; p = 0.038, respectively).

Conclusions

The number of examined lymph nodes, the NR and LODDS are useful for further prognostic stratification of N1 patients in the setting of pancreatectomy combined with PV/SMV resection. No superiority of one over the others methods was detected.

Prognostic impact of nodal statuses in patients with pancreatic ductal adenocarcinoma

BACKGROUND

The present study aimed to clarify the prognostic impact of nodal statuses in pancreatic ductal adenocarcinoma (PDAC) after potentially curative pancreatectomy.

METHODS

In 110 patients with >10 examined lymph nodes (ELNs), we investigated how nodal statuses were associated with postoperative survival. Nodal statuses included the number of positive LNs (PLNs); the ratio of PLNs to ELNs (lymph node ratio; LNR); and the location of regional LN metastases, classified as group one (peripancreatic area) and group 2 (outside the peripancreatic area). The maximum χ² value, provided by a Cox proportional hazards model, was used to determine the optimal cutoff value for the number of PLNs and the LNR.

RESULTS

The median numbers of ELNs and metastatic LNs were 33 and 2, respectively. Median survival was longer in patients with ≤3 PLNs (37.5 months), LNR <0.11 (36.1 months), and group 1 LN metastases (37.5 months) compared to in patients with ≥4 PLNs (23.7 months), LNR ≥0.11 (23.9 months), and group 2 LN metastases (22.8 months), respectively. Multivariate analyses revealed that all three investigated nodal statuses were independent factors associated with survival: HR of 2.38 and p = 0.0006 for the location of LN metastases, HR of 1.92 and p = 0.0071 for the number of PLNs, and HR of 1.89 and p = 0.010 for the LNR.

CONCLUSIONS

Three nodal statuses-the number of PLNs, the LNR, and the location of LN metastases-could stratify postoperative survival among PDAC patients with an adequate number of examined LNs after pancreatectomy.

Number of evaluated lymph nodes and positive lymph nodes, lymph node ratio, and log odds evaluation in early-stage pancreatic ductal adenocarcinoma: numerology or valid indicators of patient outcome?

BACKGROUND

We evaluated the prognostic significance and universal validity of the total number of evaluated lymph nodes (ELN), number of positive lymph nodes (PLN), lymph node ratio (LNR), and log odds of positive lymph nodes (LODDS) in a relatively large and homogenous cohort of surgically treated pancreatic ductal adenocarcinoma (PDAC) patients.

METHODS

Prospectively accrued data were retrospectively analyzed for 282 PDAC patients who had pancreaticoduodenectomy (PD) at our institution. Long-term survival was analyzed according to the ELN, PLN, LNR, and LODDS.

RESULTS

Of these patients, 168 patients (59.5 %) had LN metastasis (N1). Mean ELN and PLN were 13.5 and 1.6, respectively. LN positivity correlated with a greater number of evaluated lymph nodes; positive lymph nodes were identified in 61.4 % of the patients with ELN ≥ 13 compared with 44.9 % of the patients with ELN < 13 (p = 0.014). Median overall survival (OS) and 5-year OS rate were higher in N0 than in N1 patients, 22.4 vs. 18.7 months and 35 vs. 11 %, respectively (p = 0.008). Mean LNR was 0.12; 91 patients (54.1 %) had LNR < 0.3. Among the N1 patients, median OS was comparable in those with LNR ≥ 0.3 vs. LNR < 0.3 (16.7 vs. 14.1 months, p = 0.950). Neither LODDS nor various ELN and PLN cutoff values provided more discriminative information within the group of N1 patients.

CONCLUSIONS

Our data confirms that lymph node positivity strongly reflects PDAC biology and thus patient outcome. While a higher number of evaluated lymph nodes may provide a more accurate nodal staging, it does not have any prognostic value among N1 patients. Similarly, PLN, LNR, and LODDS had limited prognostic relevance.

Appraisal of Laparoscopic Distal Pancreatectomy for Left-Sided Pancreatic Cancer: A Large Volume Cohort Study of 152 Consecutive Patients

BACKGROUND

The aim of this study was to appraise the value of laparoscopic distal pancreatectomy (LDP) for left-sided pancreatic cancer based on a large volume cohort study.

METHODS

We reviewed data for all consecutive patients undergoing LDP for left-sided pancreatic cancer at Asan Medical Center (Seoul, Korea) between December 2006 and December 2014.

RESULTS

A total of 91 male and 61 female patients, with a median age of 62.7 years were included in this study. The median operative duration was 234 minutes. Pathological reports revealed the following: a median tumor size of 3.0 cm (range, 0.4-10.0), T stages (T1 in 7.9%, T2 in 5.3%, T3 in 86.8%, and no T4), the tumor differentiation (well differentiated in 16.4%, moderately differentiated in 75.4%, and poorly differentiated in 8.2%), and R0 resection in 126 patients (82.9%). After pancreatectomy, 96 patients (63.2%) received adjuvant chemotherapy, and the median time to chemotherapy was 30 days. The median length of hospital stay was 8 days (range, 5-31), and the median time to diet resumption was 1 day. Grade B or C postoperative pancreatic fistula occurred in 14 patients (9.2%) and grade II or III complications occurred in 27 (17.7%). The median overall survival was 43.0 months. A Cox proportional hazards model showed that tumor size, N1 stage, combined resection, and incompleteness of planned adjuvant chemotherapy affect patient survival.

CONCLUSIONS

LDP for left-sided pancreatic cancer is reasonable within selected indications. An international consensus on laparoscopic surgery for pancreatic cancer would be desirable and timely.

Identification of an N staging system that predicts oncologic outcome in resected left-sided pancreatic cancer

In this study, we investigated which N staging system was the most accurate at predicting survival in pancreatic cancer patients.Lymph node (LN) metastasis is known to be one of the important prognostic factors in resected pancreatic cancer. There are several LN evaluation systems to predict oncologic impact.From January 1992 to December 2014, 77 medical records of patients who underwent radical pancreatectomy for left-sided pancreatic cancer were reviewed retrospectively. Clinicopathologic variables including pN stage, total number of retrieved LNs (N-RLN), lymph node ratio (LNR), and absolute number of LN metastases (N-LNmet) were evaluated. Disease-free survival (DFS) and disease-specific survival (DSS) were analyzed according to these 4 LN staging systems.In univariate analysis, pN stage (pN0 vs pN1: 17.5 months vs 7.9 months, P = 0.001), LNR (<0.08 vs ≥0.08: 17.5 months vs 4.4 months, P < 0.001), and N-LNmet (#N = 0 vs #N = 1 vs #N≥2: 17.5 months vs 11.0 months vs 6.4 months, P = 0.002) had a significant effect on DFS, whereas the pN stage (pN0 vs pN1: 35.3 months vs 16.7 months, P = 0.001), LNR (<0.08 vs ≥0.08: 37.1 months vs 15.0 months, P < 0.001), and N-LNmet (#N = 0 vs #N = 1 vs #N≥2: 35.3 months vs 18.4 months vs 16.4 months, P = 0.001) had a significant effect on DSS. In multivariate analysis, N-LNmet (#N≥2) was identified as an independent prognostic factor of oncologic outcome (DFS and DSS: Exp (β) = 2.83, P = 0.001, and Exp (β) = 3.17, P = 0.001, respectively).Absolute number of lymph node metastases predicted oncologic outcome in resected left-sided pancreatic cancer patients.

Standardization of surgical care in a high-volume center improves survival in resected pancreatic head cancer

BACKGROUND

Durable clinical gains in surgical care are frequently reliant on well-developed standardization of practices. We hypothesized that the standardization of surgical management would result in improved long-term survival in pancreatic cancer.

METHODS

Seventy-seven consecutive, eligible patients representing all patients who underwent pancreaticoduodenectomy and received comprehensive, long-term postoperative care at the University of Florida were analyzed. Patients were divided into prestandardization and poststandardization groups based on the implementation of a pancreatic surgery partnership, or standardization program.

RESULTS

Standardization resulted in a reduction in median length of stay (10 vs 12 days; P = .032), as well as significant gains in disease-free survival (17 vs 11 months; P = .017) and overall survival (OS; 26 vs 16 months; P = .004). The improvement in overall survival remained significant on multivariate analysis (hazard ratio = .46, P = .005).

CONCLUSIONS

Standardization of surgical management of pancreatic cancer was associated with significant gains in long-term survival. These results suggest strongly that management of pancreatic head adenocarcinoma be standardized likely by regionalization of care at high performing oncologic surgery programs.