N0/N1, PNL, or LNR? The effect of lymph node number on accurate survival prediction in pancreatic ductal adenocarcinoma

Clinical Implications of Extensive Lymph Node Metastases for Resected Pancreatic Cancer

BACKGROUND

Outcomes of patients with resected pancreatic ductal adenocarcinoma (PDA) and extensive lymph node metastases have not been fully characterized.

METHODS

A total of 637 patients underwent resection for pancreatic ductal adenocarcinoma (PDA) between 2002 and 2014 at the Thomas Jefferson University. Positive lymph node count (LNC) and positive lymph node ratio (LNR) were analyzed as predictors of cancer-specific outcomes, with a focus on outcomes of patients with extensive lymph node burden.

RESULTS

Resected patients with regional lymph node metastases had a median survival of 17.1 months (n = 425, 70%) compared with 25.5 months (n = 185, 30%) for patients without lymph node spread (N0) (hazard ratio [HR] = 1.9, p < 0.001). Overall survival decremented with increased lymph node spread, but plateaued for LNC ≥ 4 (HR 2.4 vs. N0, p < 0.001) and LNR ≥ 0.4 (HR 2.2, p < 0.001). Compared with historical cohorts with macroscopic metastatic disease, as opposed to microscopic, superior long-term survival was achieved in patients with extensive lymph node metastases (LNC ≥ 4); 24- and 36-month survivals were 25% (vs. 16%, p < 0.001) and 12% (vs. 6%, p < 0.001), respectively. Extensive lymph node burden was associated with increased baseline postoperative serum CA 19-9 (p = 0.044) and systemic recurrence (p < 0.001).

CONCLUSIONS

The prognostic impact of extensive lymph node spread after resection for PDA plateaus above a specific threshold (LNC ≥ 4 or LNR ≥ 0.4), supporting the new 8th edition AJCC criteria for N2 disease. Clinically, lymph node spread above this threshold seems to correlate with occult systemic disease (elevated postoperative CA 19-9 and systemic pattern of failure).

A Refined Staging Model for Resectable Pancreatic Ductal Adenocarcinoma Incorporating Examined Lymph Nodes, Location of Tumor and Positive Lymph Nodes Ratio

Background: Nodal status and tumor site are prognostic factors for resectable pancreatic ductal adenocarcinoma (PDAC). Parameters for nodal status are diverse, and the number of examined lymph nodes (eNs) needed for good prognosis are uncertain. We try to modify staging system of resectable PDAC with parameters mentioned above by recursive partitioning analysis.

Methods: Patients from the Surveillance, Epidemiology, and End Results (SEER) database were divided into training cohort and internal validation cohort, randomly. PDAC patients from Sun Yat-sen University Cancer Center were regarded as external validation cohort. The training cohort was used to refine staging model by recursive partitioning analysis, while the internal validation cohort and the external validation cohort were applied to assess discriminatory capacity of staging model. For parameters included in the modified model, their effects were studied.

Results: The number of eNs, tumor site and tumor size were risk factors for positive nodal status. Lymph nodes ratio (LNR), tumor site, eNs and T stages of 8^th the American Joint Committee on Cancer (AJCC) were selected to develop a refined model, dividing patients into 5 groups of different outcomes, preceding 8^th AJCC classification. Besides, we found that (1) for small PDAC (diameter < 1cm), lymph node metastasis was rarely found; (2) enough eNs were needed to ensure better prognosis of node-negative patients; (3) tumors in the head of pancreas were prone to lymph nodes metastasis; (4) for node-positive patients, LNR was a better nodal parameter compared to positive lymph nodes (pNs).

Conclusion: Our improved staging system helps to illuminate the interactions among tumor site, size and eNs.

Exploration of the Exact Prognostic Significance of Lymphatic Metastasis in Jejunoileal Neuroendocrine Tumors

BACKGROUND

How to evaluate the prognostic significance of lymphatic metastasis in patients with small bowel (jejunoileal) neuroendocrine tumors (SBNETs) is still not conclusive.

METHODS

Data for patients with SBNETs, but without distant metastasis, were retrieved from the Surveillance, Epidemiology, and End Results database. Recursive partitioning analysis (RPA) was used for classification development by combining examined lymph nodes (ELNs) and lymph node ratio (LNR).

RESULTS

Overall, 1925 patient records were retrieved. Patients with N0 and N1 disease (based on the definition of the European Neuroendocrine Tumor Society [ENETS] staging classification) did not have different OS (p = 0.7867), nor did patients with N0, N1 (< 12 positive nodes), and N2 (≥ 12 positive nodes) disease based on the definition of American Joint Committee on Cancer (AJCC) 8th edition staging classification (p = 0.5276). However, Cox regression analysis indicated that both ELNs (hazard ratio [HR] 0.968, 95% confidence interval [CI] 0.949-0.987; p = 0.0013) and LNR (HR 2.288, 95% CI 1.122-3.682; p = 0.0006) were prognostic factors. Using RPA, we combined ELNs and LNR, and patients were reclassified into three groups (group 1: ELNs ≥ 12, any LNR; group 2: ELNs < 12, LNR < 0.35; group 3: ELNs < 12, LNR ≥ 0.35). Survival analysis and multivariate Cox regression showed that groups 1, 2, and 3 had progressively worse survival. Furthermore, we found that ELNs ≥ 12 could remarkably improve patient survival (p < 0.001).

CONCLUSIONS

The current definition of lymphatic metastasis could not help predict patient survival. Our newly proposed classification of lymphatic metastasis is better than the ENETS and AJCC 8th edition staging classifications in evaluating the prognostic significance of lymphatic metastasis in SBNETs. Systematic resection of lymph nodes (≥ 12) could help improve patient survival.

Autophagy Inhibition in Pancreatic Adenocarcinoma

Although some progress has been made in recent years with the development of more effective chemotherapy regimens, new treatment approaches are needed to improve outcomes for patients with pancreatic adenocarcinoma. The cellular process of autophagy, a cell survival mechanism that allows cancer cells to survive the hazardous conditions of the tumor microenvironment and treatment, has emerged as a viable target in pancreatic cancer. We review the mechanism of autophagy, its role in pancreatic carcinogenesis, the preclinical and clinical evidence supporting targeting autophagy in patients with pancreatic adenocarcinoma, and areas of future investigation that hold promise for improving this treatment approach.

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.

Lymph node 8a as a prognostic marker for poorer prognosis in pancreatic and periampullary carcinoma

OBJECTIVES

An investigation of patients with pancreatic carcinoma aims to identify those who will benefit from surgery. Physical examination, radiology and laboratory findings are helpful. Most prognostic markers, such as lymph node status, micro metastasis and tumour differentiation, are not preoperatively accessible. Metastatic disease in lymph node 8a (Ln8a) in patients operated for pancreatic carcinoma has been reported to be a predictor of shorter overall survival (OS). This lymph node can be assessed preoperatively through resection (possibly even with laparoscopy) and subsequent histopathology. The value of the procedure is disputed. The aim of this study is to investigate whether metastatic disease in Ln8a is a predictor of decreased OS.

MATERIALS AND METHODS

In patients with suspected pancreatic or periampullary carcinoma, who were operated with pancreatoduodenectomy (PD), Ln8a was separately resected and analysed with standard and immuno-histochemical methods. Patients with or without metastasis in Ln8a were compared regarding OS.

RESULTS

Between 2008 and 2011, 122 consecutive patients were eligible and 87 were resected and had LN8a analysed separately. Sixteen patients were Ln8a + and 71 were Ln8a-. Patients with Ln8a + had a significantly reduced median OS as compared to patients with Ln8a- (0.74 (95% CI 0.26-1.26) versus 5.91 years (95% CI 2.91-), p < .001).

CONCLUSION

Ln8a + was associated with a marked reduction of OS, indicating a possible role in the future preoperative workup in patients with a suspicion of pancreatic cancer.

Can standardized pathology examination increase the lymph node yield following laparoscopic distal pancreatectomy for ductal adenocarcinoma?

BACKGROUND

Lymph node yield (LNY) is an indicator of oncological adequacy of surgery in patients with pancreatic ductal adenocarcinoma (PDAC). Our hypothesis is that standardized pathology examination (SPE) aimed at accurate staging can increase the LNY without changing surgical technique.

METHODS

After the introduction of SPE for distal pancreatosplenectomy specimens at Oslo University Hospital, prospective data were collected on patients with PDAC undergoing laparoscopic distal pancreatosplenectomy (LDP). Their data were compared with retrospective data from specimens examined in a non-standardized way (NSPE).

RESULTS

SPE and NSPE were applied to 20 and 33 specimens, respectively. SPE was associated with a higher LNY and a higher median number of positive lymph nodes (PLN) in the specimen (18 vs 7, P = 0.001 and 4 vs 1, P = 0.005, respectively). In the stepwise regression model, SPE and younger age resulted in an increased LNY. In the logistic regression model, increased LNY and larger tumor size positively correlated with the presence of PLN.

CONCLUSION

SPE of distal pancreatosplenectomy specimens is associated with higher LNY in patients with PDAC, which increases the likelihood of detecting PLN and reduces the risk of understaging. These findings also indicate that the LDP technique provides an adequate LNY in patients with PDAC.

Histologic Tumor Grade and Preoperative Bilary Drainage are the Unique Independent Prognostic Factors of Survival in Pancreatic Ductal Adenocarcinoma Patients After Pancreaticoduodenectomy

BACKGROUND AND AIM

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal types of cancer; most patients die during the first 6 months after diagnosis. With a 5% 5-year survival rate, is the fourth leading cause of cancer death in developed countries. In this regard, several clinical, histopathologic and biological characteristics of the disease favoring long-term survival after pancreaticoduodenectomy have been reported to be significant prognostic factors. Despite the availability of this information, there is no consensus about the different prognostic factors reported in the literature, probably due to variations in patient selection, methods, and sample size studied. The aim of this study was to identify the clinical and pathologic features associated to prognosis of the disease after pancreaticoduodenectomy.

MATERIALS AND METHODS

The clinical and pathologic data from 78 patients who underwent a potentially curative resection for PDAC at our institution between 2003 and 2014 were analyzed retrospectively.

RESULTS

Overall, high-grade PDAC cases showed larger tumor size (P=0.009) and a higher frequency of deaths in association with a nonsignificantly shortened patient overall survival (median of 12.5 vs. 21.7 mo; P=0.065) as compared with low-grade PDAC patients. High histologic grade (P=0.013), preoperative drainage on the main bile duct (P=0.014) and absence of adjuvant therapy (P=0.035) were associated with a significantly poorer outcome. Overall survival multivariate analysis showed histologic grade (P=0.019) and bile duct preoperative drainage (P=0.016) as the sole independent variables predicting an adverse outcome.

CONCLUSIONS

Our results indicate that histologic tumor grade and preoperative biliary drainage are the only significant independent prognostic factors in PDAC patients after pancreatectomy.

Which patients with para-aortic lymph node (LN16) metastasis will truly benefit from curative pancreaticoduodenectomy for pancreatic head cancer?

In patients with cancer of the pancreatic head, metastasis to para-aortic lymph nodes (LN16) is considered distant metastasis and a poor prognostic marker. However, the incidence of LN16 involvement in pancreatic head cancer is high, and it is unclear whether all such patients have poor surgical outcomes. We investigated the significance of LN16 involvement in resectable pancreatic head cancer by retrospectively analyzing 579 ductal adenocarcinoma patients treated with para-aortic lymph node dissection at two high-volume Chinese centers. Depending upon tumor location, the incidence of LN16 metastasis and the correlation between LN16 involvement and involvement of Group 1 or 2 lymph nodes significantly differed. Metastasis to LN16 indicated a high serum tumor burden and a poor prognosis, though LN16-positive patients with a lymph node ratio (LNR) < 0.25 may still benefit from radical surgery. Survival analysis of LN16-positive patients with resectable pancreatic head cancer revealed that tumor size, tumor differentiation, and tumor location are independent prognostic factors. We also found that preoperative serum CA125 < 18.62 U/ml and the level of JAK2 signaling are both indicators of who may benefit from curative surgical resection for pancreatic head cancer.

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.

The number of positive lymph node is a better predictor of survival than the lymph node metastasis status for pancreatic neuroendocrine neoplasms: A retrospective cohort study

BACKGROUND

The recently released AJCC TNM staging system of pancreatic adenocarcinoma has endorsed the number of positive lymph node(NPLN) as the criterion of N staging. However, the prognostic role of NPLN is still unclear for pancreatic neuroendocrine neoplasms (pNENs).

METHODS

Patients underwent resection and at least one lymph node examined were identified from the Surveillance, Epidemiology, and End Results database. The overall survival (OS) and disease specific survival (DSS) were estimated using Kaplan-Meier analysis and compared by log-rank test. The prognostic factors were determined by cox proportional regression model.

RESULTS

Totally, 1,269 pNENs were included in the present study. The increasing NPLN (NPLN > 3) was corresponding significantly (P < 0.05) shorter OS and DSS in both entire cohort (OS: NPLN ≤ 3 vs. NPLN > 3, 93.624 ± 1.765 months vs. 75.075 ± 4.005 months; DSS: NPLN ≤ 3 vs. NPLN > 3, 104.829 ± 1.455 months vs. 85.443 ± 3.938 months, respectively) and cohort with the number of examined lymph node more than 11 (OS: NPLN ≤ 3 vs. NPLN > 3, 88.759 ± 2.756 months vs. 73.664 ± 4.700 months; DSS: NPLN ≤ 3 vs. NPLN > 3, 99.021 ± 2.212 months vs. 85.139 ± 4.686 months, respectively). Furthermore, the multivariate analysis showed the NPLN > 3 rather than lymph node status was the independent prognostic factors for OS and DSS in these two cohorts.

CONCLUSIONS

The NPLN seems more meaningful than the lymph node metastasis status as prognostic factor for survival. Taking into account the prognostic value of NPLN for pNENs might improve the current TNM staging systems. However, prospective study is needed to demonstrate our findings.

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

Background:

Few studies have simultaneously assessed the prognostic value of the multiple classification systems for lymph node (LN) metastases in resected pancreatic ductal adenocarcinoma (PDAC).

Methods:

In 600 patients with resected PDAC, we examined the association of LN parameters (AJCC 7th and 8th editions, LN ratio (LNR), and log odds of metastatic LN (LODDS)) with pattern of recurrence and patient survival using logistic regression and Cox proportional hazards regression, respectively. Regression models adjusted for age, sex, margin status, tumour grade, and perioperative therapy.

Results:

Lymph node metastases classified by AJCC 7th and 8th editions, LNR, and LODDS were associated with worse disease free-survival (DFS) and overall survival (OS) (all P_trend<0.01). American Joint Committee on Cancer 8th edition effectively predicted DFS and OS, while minimising model complexity. Lymph node metastases had weaker prognostic value in patients with positive margins and distal resections (both P_interaction<0.03). Lymph node metastases by AJCC 7th and 8th editions did not predict the likelihood of local disease as the first site of recurrence.

Conclusions:

American Joint Committee on Cancer 8th edition LN classification is an effective and practical tool to predict outcomes in patients with resected PDAC. However, the prognostic value of LN metastases is attenuated in patients with positive resection margins and distal pancreatectomies.

The More the Better-Lower Rate of Stage Migration and Better Survival in Patients With Retrieval of 20 or More Regional Lymph Nodes in Pancreatic Cancer: A Population-Based Propensity Score Matched and Trend SEER Analysis

OBJECTIVE

The aim of this study was to assess the influence of regional lymph node (RLN) retrieval on stage migration and survival in pancreatic cancer.

METHODS

A total of 7685 stage I and II pancreatic cancer patients were identified in the Surveillance, Epidemiology, and End Results database in 2004-2011. The impact of RLN was assessed using Cox regression, propensity score methods, and joinpoint regression.

RESULTS

In 3079 patients, 1 to 10 RLNs were retrieved; in 2799 patients, 11 to 19 RLNs, and in 1807 patients, 20+ RLNs. The rate of node-positive pancreatic cancer increased with the number of retrieved RLN. This trend continued beyond 10 retrieved RLN (P < 0.001). In unadjusted analysis, retrieval of RLN did not influence survival (P = 0.178). When adjusting for significant bias in staging variables (P < 0.001), retrieval of 20+ RLNs compared to 11 to 19 RLNs was associated with an increased survival in node-negative (hazard ratio, 0.78; 95% confidence interval, 0.62-0.98; P = 0.033) and node-positive cancer (hazard ratio, 0.83; 95% confidence interval, 0.74-0.93; P = 0.002).

CONCLUSIONS

This population-based propensity score-adjusted investigation demonstrated that more retrieved RLNs in pancreatic cancer decreases the rate of stage migration and improves the oncological outcome in node-negative and positive cancer. Contradictory results may be explained by a bias in the cancer characteristics for a different extent of RLN retrieval.

Staging of pancreatic cancer based on the number of positive lymph nodes

BACKGROUND

The International Study Group on Pancreatic Surgery has stated that at least 12 lymph nodes should be evaluated for staging of pancreatic cancer. The aim of this population-based study was to evaluate whether the number of positive lymph nodes refines staging.

METHODS

Patients who underwent pancreatectomy for stage I-II pancreatic cancer between 2004 and 2012 were identified from the Surveillance, Epidemiology, and End Results database. The predictive value of the number of positive lymph nodes for survival was assessed by generalized receiver operating characteristic (ROC) curve analysis and propensity score-adjusted Cox regression analysis.

RESULTS

Some 5036 patients were included, with a median of 18 (i.q.r. 15-24) lymph nodes examined. Positive lymph nodes were found in 3555 patients (70·6 per cent). The median duration of follow-up was 15 (i.q.r. 8-28) months. ROC curve analysis revealed that two positive lymph nodes best discriminated overall survival. Patients with one or two positive lymph nodes (pN1a) and those with three or more positive lymph nodes (pN1b) had an increased risk of overall mortality compared with patients who were node-negative (pN0): hazard ratio (HR) 1·47 (95 per cent c.i. 1·33 to 1·64) and HR 2·01 (1·82 to 2·22) respectively. These findings were confirmed by propensity score-adjusted Cox regression analysis. The 5-year overall survival rates were 39·8 (95 per cent c.i. 36·5 to 43·3) per cent for patients with pN0, 21·0 (18·6 to 23·6) per cent for those with pN1a and 11·4 (9·9 to 13·3) per cent for patients with pN1b disease.

CONCLUSION

The number of positive lymph nodes in the resection specimen is a prognostic factor in patients with pancreatic cancer.

Multimodal treatment of resectable pancreatic ductal adenocarcinoma

After a timing preoperative staging, treatment of resectable pancreatic adenocarcinoma (PDAC) includes surgery and adjuvant therapies, the former representing the initial therapeutic option and the latter aiming to reduce the incidence of both distant metastases (chemotherapy) and locoregional failures (chemoradiotherapy). Herein, we provide a critical overview on the role of multimodal treatment in PDAC and on new opportunities related to current more active poli-chemotherapy regimens, targeted therapies, and the more recent immunotherapy approaches. Moreover, an analysis of pathological markers and clinical features able to help clinicians in the selection of the best therapeutic strategy will be discussed. Lastly, the role of neoadjuvant treatment of initially resectable disease will be considered mostly in patients whose malignancy shows morphological but not clinical or biological criteria of resectability. Depending on the results of these investigational studies, today a multidisciplinary approach can offer the best address therapy for these patients.

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.

Clinical significance of accurate identification of lymph node status in distant metastatic gastric cancer

PURPOSE

The clinical consequences of accurately identifying lymph node (LN) status in distant metastatic gastric cancer (DMGC) are unclear. We aimed to determine the prognostic significance of N stage, positive LN (PLN) count, and the positive LN ratio (LNR). We also retrospectively compared survival outcomes of DMGC patients stratified by LN dissection (LND).

RESULTS

LND was performed in 1593 patients. The CSS was significantly different between groups divided according to N stage, PLN, and LNR in DMGC patients who underwent LND. Lower LNR was an independent predictor of longer survival in all kinds of patients cohorts, whereas PLN was not such a predictor. PLN count correlated with LND number and LNR. No correlation existed between LNR and LND number. Undergoing LND and having a higher number of dissected LNs were associated with superior CSS.

MATERIALS AND METHODS

Data from 1889 DMGC patients treated between 2004 and 2009, and documented in the Surveillance, Epidemiology, and End Results (SEER) registry, were reviewed. Pearson's correlation coefficient and the Chi-square test were used to study the relationships between LND number, PLN count, N stage, and the LNR. Cancer-specific survival (CSS) was evaluated using Kaplan-Meier analysis, with the log-rank test performed for univariate analysis (UVA) and the Cox proportional hazards model employed for multivariate analysis (MVA).

CONCLUSION

LN metastatic variables play important roles in the prognostic evaluation and treatment decisions of DMGC patients. Accurate identification of LN status in DMGC patients is critical. LND performance is associated with increased survival and has clinical practicability.

MicroRNA Expression in a Readily Accessible Common Hepatic Artery Lymph Node Predicts Time to Pancreatic Cancer Recurrence Postresection

Lymph node involvement in pancreatic adenocarcinoma (PAC) predicts postresection survival, but early lymph node metastasis detection is not easily accomplished. We assessed a panel of microRNAs (miRNAs) in a common hepatic artery lymph node (station 8) that is readily accessible during pancreatoduodenectomy (PD) to determine if increased miRNA levels correlate with postresection recurrence. Station 8 lymph nodes overlying the common hepatic artery collected during PD were assayed for miRNA-10b, miRNA-30c, miRNA-21, and miRNA-155 and cytokeratin-19 (CK19), an epithelial cell marker, using quantitative PCR. Expression was correlated with disease recurrence, recurrence-free survival (RFS), and overall survival (OS). Station 8 lymph nodes from 37 patients (30 periampullary carcinomas (PCs), 2 chronic pancreatitis, 5 other cancers) exhibited increased miRNA-10b levels in 14/30 PCs, and in 10 of these 14 patients, cancer recurred during the study period (2012-2015). High miRNA-10b was also associated with shorter RFS (42.5 vs. 92.4 weeks, p < 0.05) but not OS, whereas miRNA-30c, miRNA-21, and miRNA-155 levels and CK19 mRNA levels in station 8 nodes were variable and did not correlate with RFS or OS. We conclude that elevated miRNA-10b levels in station 8 lymph nodes could be utilized to assess risk for early disease progression in patients with periampullary tumors.

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.

Minimally invasive pancreaticoduodenectomy: A comprehensive review

BACKGROUND

While an increasing number of open procedures are now routinely performed laparoscopically or robotically, minimally invasive pancreaticoduodenectomy (MIPD) remains one of the most challenging operations in abdomen. The aim of this study is to evaluate the current status and development of MIPD.

METHODS

Embase, Medline, and PubMed databases were searched to identify studies up to and including Feb 2016 using the keywords "laparoscopic", or "laparoscopy", or "hand-assisted", or "minimally invasive", or "robotic", or "da vinci" combined with "pancreaticoduodenectomy", or "duodenopancreatectomy", "Whipple", or "pancreatic resection". Articles written in English with more than 10 cases were included for review.

RESULTS

Thirty-two articles representing 2209 patients were included for review. The weighted average operative time and intraoperative blood loss was 427.3 min and 289.4 mL respectively. A total of 375 patients required conversion to open pancreaticoduodenectomy (OPD), with an overall conversion rate of 17.8%. The postoperative severe complications (the Clavien-Dindo Classification ≥ III) occurred in 3.8%-33.0% patients, with an overall severe morbidity of 14.3%. Particularly, the overall incidence of clinically significant postoperative pancreatic fistula (POPF) was 8.0%. There were 26 perioperative death cases in total, with an overall postoperative mortality rate of 2.3%. The weighted average number of collected lymph nodes was 17.9, and R0 resection ranged from 60.0% to 100.0%. Comparisons between MIPD and OPD showed that MIPD increased operative time, decreased intraoperative blood loss and shortened the length of hospital stay, but the overall morbidity and mortality were comparable.

CONCLUSIONS

MIPD is technically feasible and safe in highly selected patients and can offer acceptable oncological outcomes. But concerns such as long-term outcomes, cost-effectiveness analysis, and learning curve analysis should be fully demonstrated before the popularization of this challenging procedure.

A matched-cohort analysis of 192 pancreatic anaplastic carcinomas and 960 pancreatic adenocarcinomas: A 13-year North American experience using the National Cancer Data Base (NCDB)

BACKGROUND

Anaplastic pancreatic carcinoma (APC) is a rare and poorly characterized disease. We sought to compare the clinical characteristics and outcomes of APC to pancreatic adenocarcinoma (PDAC).

METHODS

The American National Cancer Data Base was queried for patients with resected APC and PDAC using histologic and operative codes. APC cases were matched 1:5 with PDACs based on age, sex, pathologic tumor stage, operative margin status, lymph node positivity ratio, and use of adjuvant chemotherapy.

RESULTS

After 1:5 matching, 192 APCs and 960 PDACs were analyzed. When comparing APC vs PDAC the median tumor size was 45 mm (interquartile range, 33-60) vs 30 mm (interquartile range, 23-40; P < .001), and metastatic nodal disease was present in 40.6% and 38.0% of the cases (P = .25), respectively. APC cases were distributed equally between the head and the body/tail region of the pancreas (50%), while PDAC cases were located mainly in the head of the pancreas (75%; P < .001). Although the resected APC group had a lesser survival during the first year after the diagnosis (51% vs 69%; P = .029), the overall survival was similar in the 2 groups, with 21.6% vs 17.4% alive at 5 years, respectively for APC and PDAC (P = .32). Subgroup analysis of patients with APC with (n = 18) versus those without (n = 80) osteoclastlike giant cells showed a greater 5-year survival (50% versus 15%, P < .001).

CONCLUSION

Patients with resected APC tend to present with large tumors equally distributed between the head and body/tail of the pancreas. While APC is thought to have a more aggressive biology, our matched analysis showed similar overall survival compared with PDAC. The presence of osteoclastlike giant cells portends a significantly better prognosis compared with other histologic features of APCs.

Re-evaluation of classical prognostic factors in resectable ductal adenocarcinoma of the pancreas

Pancreatic ductal adenocarcinoma carries a poor prognosis with annual deaths almost matching the reported incidence rates. Surgical resection offers the only potential cure. Yet, even among patients that undergo tumor resection, recurrence rates are high and long-term survival is scarce. Various tumor-related factors have been identified as predictors of survival after potentially curative resection. These factors include tumor size, lymph node disease, tumor grade, vascular invasion, perineural invasion and surgical resection margin. This article will re-evaluate the importance of these factors based on recent publications on the topic, with potential implications for treatment and outcome in patients with pancreatic cancer.

Pancreatic cancer metastatic to a limited number of lymph nodes has no impact on outcome

BACKGROUND

The purpose of this study was to determine the association of the extent of metastatic lymph node involvement with survival in pancreatic cancer.

METHODS

This is a retrospective review of a prospectively maintained database of patients who underwent resection for pancreatic adenocarcinoma, 1999-2011.

RESULTS

165 patients were identified and divided into 3 groups based on the number of positive lymph nodes - 0 (group A), 1-2 (B), >3 (C). Each group had 55 patients. Those in group C were more likely to have a higher T stage, poorly differentiated grade, lymphovascular invasion (LVI), higher mean intraoperative blood loss, positive margins, tumor location involving the uncinate process, and a higher likelihood of undergoing a pancreaticoduodenectomy. Median overall survival (OS) for group A, B and C was 25.5 months (mo), 21 mo and 12.3 mo, respectively (p < 0.001). No survival difference was noted for survival between groups A and B (p = 0.86). The ratio of involved lymph nodes <0.2 was predictive of improved survival (p < 0.001).

CONCLUSIONS

Resected pancreatic cancer patients with only 1-2 positive lymph nodes or less than 20% involvement have a similar prognosis to patients without nodal disease. Current staging should consider stratification based on the extent of nodal involvement.

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.

Learning Curve for Laparoscopic Pancreaticoduodenectomy: a CUSUM Analysis

BACKGROUND

Laparoscopic pancreaticoduodenectomy (LPD), an advanced minimally invasive technique, has demonstrated advantages to open pancreaticoduodenectomy (OPD). However, this complex procedure requires a relatively long training period to ensure technical proficiency. This study was therefore designed to analyze the learning curve for LPD.

METHODS

From October 2010 to September 2015, 63 standard pancreaticoduodenectomy procedures were to be performed laparoscopically by a single surgeon at the Department of Pancreatic Surgery, West China Hospital, Sichuan University, China. After applying the inclusion and exclusion criteria, a total of 57 patients were included in the study. Data for all the patients, including preoperative, intraoperative, and postoperative variables, were prospectively collected and analyzed. The learning curve for LPD was evaluated using both cumulative sum (CUSUM) and risk-adjusted CUSUM (RA-CUSUM) methods. All of the variables among the learning curve phases were compared.

RESULTS

Based on the CUSUM and the RA-CUSUM analyses, the learning curve for LPD was grouped into three phases: phase I was the initial learning period (cases 1-11), phase II represented the technical competence period (cases 12-38), and phase III was regarded as the challenging period (cases 39-57). The operative time, intraoperative blood loss, and postoperative ICU demand significantly decreased with the learning curve. More lymph nodes were collected after the initial learning period. There were no significant differences in terms of postoperative complications or the 30-day mortality among the three phases. More challenging cases were encountered in phase III.

CONCLUSIONS

According to this study, the learning curve for LPD consisted of three phases. Conservatively, to attain technical competence for performing LPD, a minimum of 40 cases are required for laparoscopic surgeons with a degree of laparoscopic experience.

Lymph node ratio as parameter of regional lymph node involvement in pancreatic cancer

PURPOSE

To determine which indicators, anatomical nodal metastasis (Japan Pancreas Society, JPS), number of positive lymph nodes (PLN), or lymph node ratio (LNR), is the best means of assessing lymph node involvement in pancreatic cancer.

METHODS

This retrospective study analyzed 275 patients with pancreatic cancer treated at a single institution. Survival curves according to the JPS, PLN, or LNR were assessed by the Kaplan-Meier method. Prognostic value of each classification was explored by Cox regression analysis after adjustments for clinical factors.

RESULTS

Multivariate analysis showed that, relative to n0 in the JPS, hazard ratios (HR) in n1, n2, and n3 were 1.72, 1.73, and 2.75, respectively, with no difference in survival between n1 and n2. Relative to PLN of 0, the HR in the PLN categories of 1∼2, 3, and >3 were 1.39, 1.65, and 3.03, respectively. Relative to LNR of 0, the HR in the categories of 0 < LNR ≤ 0.1, 0.1 < LNR ≤ 0.2, and LNR > 0.2 were 1.27, 2.00, and 5.58, respectively. An incremental increase in the HR was observed as the LNR category progressed, and differences between the survivals were distinct when stratified by the LNR.

CONCLUSIONS

The LNR was an accurate predictor of survival among three assessment strategies and could be proposed as a candidate for use as N categories, pending validation studies.

A model to predict survival following pancreaticoduodenectomy for malignancy based on tumour site, stage and lymph node ratio

BACKGROUND

Site of tumour origin, lymph node metastases and lymph node ratio (LNR) are identified as important factors determining prognosis in patients undergoing pancreaticoduodenectomy (PD). This study hypothesised that a prognostic index to predict survival could be developed through statistical modelling based on these pathological variables.

METHODS

Patients who underwent PD between 2004 and 2013 were included. Univariable and multivariable (Cox regression) analyses were performed to identify predictors of survival, and a prognostic index was derived. The prognostic index was then validated using an external patient cohort.

RESULTS

A total of 567 patients who underwent PD were used as a derivation cohort. Tumour site (p < 0.001), tumour size (p = 0.002), T-stage (p < 0.001), vascular involvement (p = 0.002), number of positive nodes (p < 0.001) and LNR (p < 0.001) were significantly associated with survival in univariable analysis. LNR (p < 0.001), tumour site (p < 0.001), T-stage (p = 0.007) remained significant predictors of survival in multivariable analysis, and were combined to derive a prognostic index. The accuracy of the prognostic index was assessed both on the original cohort, and a validation set of 194 patients from another institutional prospective database. The AUROC scores for predicting the overall survival at 3 years were 0.77 in the derivation cohort and 0.74 in the validation cohort.

CONCLUSION

The Pancreaticoduodenectomy Prognostic Index is a validated clinico-pathological model based on tumour site, T-stage and LNR to predict long-term survival following PD.

The prognostic impact of para-aortic lymph node metastasis in pancreatic cancer: A systematic review and meta-analysis

PURPOSE

To evaluate by a meta-analytic approach the long-term prognostic impact of para-aortic lymph node (PALN) involvement in resected ductal adenocarcinoma of the pancreas.

METHODS

MEDLINE, Embase, PubMed and the Cochrane Library were searched from January 1990 to June 2015. Trials reporting Kaplan-Meier curves and comparing overall long-term survival of negative and metastatic PALN in patients who underwent resection for pancreatic cancer were included. Lymph nodes were classified according to the Japan Pancreatic Society rules and identified using hematoxylin and eosin staining. Hazard ratios (HRs) and 95%CI were estimated for each trial and pooled in a meta-analysis.

RESULTS

Thirteen eligible studies including 2141 patients (364 positive PALN; 1777 negative PALN) were identified. Most of the studies were retrospective. Heterogeneity among trials was high (I(2) = 98.7%; p < .001). PALN metastasis was associated with increased mortality when compared with patients with negative PALN regardless regional nodal status [HR 1.85, 95%CI 1.48-2.31; p < .001]. Median survival was significantly decreased in patients with positive PALN (WMD = -4.92 months 95%CI -6.40; -3.43; p < .001). Moreover, metastatic PALN affected mortality also when regional lymph nodes were positive [HR 1.67, 95%CI 1.34-2.08; p < .001]. No publication bias was detected.

CONCLUSIONS

PALN metastasis appears to correlate with poor prognosis in patients with pancreatic adenocarcinoma. The assessment of PALN status may be considered for a more accurate staging of the disease and appropriated subgroup survival reporting. However, the definitive avoidance of the resection in case of intraoperative metastatic PALN needs further investigation.

KRAS mutations in pancreatic circulating tumor cells: a pilot study

Pancreatic ductal adenocarcinoma (PDAC) is most often diagnosed in a metastatic stage. Circulating tumor cells (CTC) in the blood are hypothesized as the means of systemic dissemination. We aimed to isolate and characterize CTC to evaluate their significance as prognostic markers in PDAC. Blood obtained from healthy donors and patients with PDAC before therapy was filtered with ScreenCell® filtration devices for size-based CTC isolation. Captured cells were analyzed by immunofluorescence for an epithelial to mesenchymal transition (EMT) marker (zinc finger E-box binding homebox 1 (ZEB1)) and an epithelial antigen (cytokeratin (CK)). Molecular analysis of parallel specimens evaluated the KRAS mutation status of the CTC. The survival of each patient after study was recorded. As demonstrated by either cytology or finding of a KRAS mutation, CTC were detected in 18 of 21 patients (86 %) with proven PDAC: 8 out of 10 patients (80 %) with early stage (UICC IIA/IIB) and 10 out of 11 (91 %) with late stage (UICC III/IV) disease. CTC were not found in any of the 10 control patients (p < 0.001). The presence of CTC did not adversely affect median survival: 16 months in CTC-positive (n = 18) vs. 10 months in CTC-negative (n = 3) patients. Neither ZEB1 nor cytological characteristics correlated with overall survival, although ZEB1 was found almost exclusively in CTC of patients with established metastases. Patients with a CTC KRAS mutation (CTC-KRAS (mut)) had a substantially better survival, 19.4 vs. 7.4 months than patients with wild type KRAS (p = 0.015). With ScreenCell filtration, CTC are commonly found in PDAC (86 %). Molecular and genetic characterization, including mutations such as KRAS, may prove useful for prognosis.

Lymph Node Evaluation for Pancreatic Adenocarcinoma and Its Value as a Quality Metric

BACKGROUND

Adequate lymph node evaluation (LNE) is recommended for surgically treated pancreatic adenocarcinoma because studies have shown an association between improved survival and adequate LNE. This study aimed to understand the mechanism of this association and determine whether LNE is a valuable quality metric.

METHODS

Using the linked Surveillance Epidemiology End Results Medicare database, we identified patients with surgically treated pancreatic adenocarcinoma from 2000 to 2010. Adequate LNE was defined as evaluation of ≥15 nodes. Survival was determined using Kaplan-Meier and Cox proportional hazards.

RESULTS

We identified 2629 patients who underwent resection for pancreatic adenocarcinoma. Overall, 33 % had adequate LNE. Adequate LNE was significantly associated with receipt of postoperative chemotherapy. A significant decrease in hazard of death was associated with adequate LNE (HR 0.86, p < 0.05). Receipt of postoperative chemotherapy was also significantly associated with decreased hazard of death (HR 0.77, p < 0.05). On unadjusted analysis, the survival benefit associated with adequate LNE was lost when stratified by receipt of postoperative chemotherapy.

CONCLUSION

The survival benefit associated with LNE is in part derived from the fact that patients who receive adequate LNE are also more likely to receive chemotherapy. Thus, the use of lymph node counts has limitations as a quality metric.

Substaging of Lymph Node Status in Resected Pancreatic Ductal Adenocarcinoma Has Strong Prognostic Correlations: Proposal for a Revised N Classification for TNM Staging

BACKGROUND

The current tumor-node-metastasis staging system for the pancreas does not incorporate the number of lymph nodes (LNs) with metastasis.

METHODS

Among 1649 pancreaticoduodenectomies, 227 stringently defined pancreatic ductal adenocarcinomas (PDACs) that had undergone a specific approach of LN harvesting were analyzed for the prognostic value of LN substaging protocols used for other gastrointestinal (GI) organs.

RESULTS

The median number of LNs harvested was 18, and the median number of LNs with metastasis was 3. Lymph node metastasis was detected in 175 cases (77 %). The number of LNs involved correlated significantly with clinical outcome. When cases were substaged with the protocol already in use for the upper GI organs (N0: no metastasis, N1: metastasis to 1-2 LNs; N2: metastasis to ≥3 LNs), the median overall survival times were 35, 21, and 18 months, and the respective 3-year survival rates were 46, 34, and 20 % (p = 0.004). Analysis of the Surveillance, Epidemiology and End Results (SEER) database also confirmed the survival differences between these substages (median overall survival times of 23, 15, and 14 months and respective 3-year survival rates of 37, 22, and 18 %; p < 0.0001). The substaging protocol for the lower GI organs (N0: no metastasis; N1: metastasis to 1-3 LNs; N2: metastasis to ≥4 LNs) also was significant, with median overall survival times of 35, 21, 18 months and respective 3-year survival rates of 46, 26, and 23 %; p = 0.009). The association between higher N stage and shorter survival persisted with multivariate modeling for both protocols, although the prognostic value of the upper GI protocol appeared to be slightly stronger according to the Akaike Information Criterion method.

CONCLUSION

In conclusion, with proper LN harvesting, the LN metastasis rate in PDACs is very high (77 %). Substaging of LN metastasis has significant prognostic value and needs to be considered in the N staging of PDACs. The protocol already in use for other upper GI tract organs, which currently also is proven significant for ampulla, would be preferable, although the lower GI tract protocol also is applicable.

Extent of lymphadenectomy to associate with pancreaticoduodenectomy in patients with pancreatic head cancer for better tumor staging

OBJECTIVES

To define the extent of lymphadenectomy to associate with surgery for pancreatic head cancer.

BACKGROUND

Pancreaticoduodenectomy with extended lymphadenectomy fails to prolong patient survival.

METHODS

Prospective randomized and nonrandomized controlled trials (RCTs and NRCTs), meta-analyses, retrospective reviews, consensus conferences and pre- and intraoperative diagnoses of lymph node (LN) metastases were retrieved. Standard and extended lymphadenectomies were reviewed, including their effects on postoperative complications, mortality rate and long-term survival. The minimum total number of LN examined (TNLE) for adequate tumor staging, and the incidence of metastasis to each LN station were also considered. A pros and cons analysis was performed on the removal of each LN station.

RESULTS

Eleven retrospective studies (2514 patients), five prospective NRCTs (545 patients), and five prospective RCTs (586 patients) described different lymphadenectomies, which obtained similar long-term results. Five meta-analyses showed they did not influence long-term survival. However, N status is an important component of tumor staging. The recommended minimum TNLE is 15. The percent incidence of metastasis to each LN station was calculated considering at least 385 and up to 3725 patients. Preoperative imaging and intraoperative exploration frequently fail to identify metastatic nodes. A pros and cons analysis suggests that lymph node status is better established removing the following LN stations: 6, 8a-p, 12a-b-c, 13a-b, 14a-b-c-d, 16b1, 17a-b. Metastasis to 16b1 LNs significantly worsens prognosis. Their removal and frozen section examination, before proceeding with resection, may contraindicate resection.

CONCLUSION

A standard lymphadenectomy demands an adequate TNLE and removal of the LN stations metastasizing more frequently, without increasing the surgical risk.

Pancreatic adenocarcinoma: number of positive nodes allows to distinguish several N categories

OBJECTIVE

To determine the prognostic value of PLN and LNR based on a large series with standardized lymphadenectomy and pathological workup.

BACKGROUND

Lymph node (LN) involvement is a major prognostic factor in pancreatic adenocarcinoma. However, the distinction N0/N1 is not sufficient to accurately predict prognosis. To improve prognostic accuracy in N1 tumors, different LN parameters have been tested. Previous studies were based on series with variable numbers of examined lymph nodes (ELN) and came to inconsistent conclusions as to the value of the number of positive lymph nodes (PLN) and the lymph node ratio (LNR).

METHODS

811 patients who underwent pancreatoduodenectomy for pancreatic adenocarcinoma between October 2001 and June 2012 were identified from a prospective database. Clinicopathological parameters included LN status (N0/N1), ELN, PLN, and LNR. Univariate and multivariate survival analyses were performed.

RESULTS

The median number of ELN was 24 (interquartile range: 18-32). By univariate analysis, both PLN and LNR were significantly associated with survival in N1 tumors. However, by multivariate analysis, only the number of PLN was confirmed as independent predictor of survival. Median survival in patients with only 1 PLN was 31.1 months and comparable to the survival in N0 (33.2 months). With increasing numbers of PLN median survival significantly decreased (2-3 PLN: 26.1 months, 4-7 PLN: 21.9 months, ≥8 PLN: 18.3 months, P < 0.0001).

CONCLUSIONS

This study demonstrates that, based on high numbers of ELN, PLN is superior to LNR in predicting survival and allows to distinguish several N-categories that improve prognostic accuracy in LN-positive resectable pancreatic adenocarcinoma.

Laparoscopic pancreaticoduodenectomy: single-surgeon experience

BACKGROUND

Innovations in surgical strategies and technologies have facilitated laparoscopic pancreaticoduodenectomy (LPD). However, data regarding the short-term and long-term results of LPD are sparse, and this procedure is the primary focus of the current study.

METHODS

Between October 2010 and October 2013, a total of 31 consecutive patients received LPD, including hand-assisted laparoscopic pancreaticoduodenectomy, total laparoscopic pancreaticoduodenectomy, and laparoscopic pylorus-preserving pancreaticoduodenectomy. Data regarding short-term surgical outcomes and long-term oncological results were collected prospectively.

RESULTS

The median operative time was 515.0 min (interquartile range 465.0-585.0 min). The median intraoperative estimated blood loss was 260.0 mL (interquartile range 150.0-430.0 mL). Conversion to open pancreaticoduodenectomy was required in three patients (9.7%) due to intraoperative pneumoperitoneum intolerance (n = 1, 3.2%) and tumor adherence to the superior mesenteric vein (n = 2, 6.5%). No significant differences between the surgical approaches were observed in regard to intraoperative and postoperative data. Postoperative severe complications (Clavien ≥ III) were detected in three (9.7%) patients, including one grade C pancreatic fistula, one grade B postoperative bleeding event, and one afferent loop obstruction. There were no deaths within 30 days following LPD. The final pathological results revealed duodenal adenocarcinoma in 14 (45.2%) patients, ampullary adenocarcinoma in four (12.9%) patients, distal common bile duct cancer in six (19.4%) patients, pancreatic ductal adenocarcinoma in five (16.1%) patients, gastrointestinal stroma tumor in one (3.2%) patient, and chronic pancreatitis in one (3.2%) patient. All patients suffering from tumors underwent R0 resection (n = 30, 100.0%), with the optimal number of collected lymph nodes (median: 13, interquartile range 11-19). At the most recent follow-up, 20 patients were still alive, and the 1-, and 3-year overall survival for patients with duodenal adenocarcinoma were 100.0 and 71.4%, respectively.

CONCLUSIONS

According to this study, LPD is feasible and technically safe for highly selected patients and can offer acceptable oncological outcomes and long-term survival.

Mesopancreas: A boundless structure, namely the rationale for dissection of the paraaortic area in pancreaticoduodenectomy for pancreatic head carcinoma

This review highlights the rationale for dissection of the 16a2 and 16b1 paraaortic area during pancreaticoduodenectomy (PD) for carcinoma of the head of the pancreas. Recent advances in surgical anatomy of the mesopancreas indicate that the retropancreatic area is not a single entity with well defined boundaries but an anatomical site of embryological fusion of peritoneal layers, and that continuity exists between the neuro lymphovascular adipose tissues of the retropancreatic and paraaortic areas. Recent advances in surgical pathology and oncology indicate that, in pancreatic head carcinoma, the mesopancreatic resection margin is the primary site for R1 resection, and that epithelial-mesenchymal transition-related processes involved in tumor progression may impact on the prevalence of R1 resection or local recurrence rates after R0 surgery. These concepts imply that mesopancreas resection during PD for pancreatic head carcinoma should be extended to the paraaortic area in order to maximize retropancreatic clearance and minimize the likelihood of an R1 resection or the persistence of residual tumor cells after R0 resection. In PD for pancreatic head carcinoma, the rationale for dissection of the paraaortic area is to control the spread of the tumor cells along the mesopancreatic resection margin, rather than to control or stage the nodal spread. Although mesopancreatic resection cannot be considered “complete” or “en bloc”, it should be “extended as far as possible” or be “maximal”, including dissection of 16a2 and 16b1 paraaortic areas.

Lymph node ratio is an independent prognostic factor for patients after resection of pancreatic cancer

Background

The prognostic value of lymph node ratio (LNR) in pancreatic cancer remains controversial. In the current retrospective study, we assessed the value of LNR on predicting the survival of postoperative patients with pancreatic cancer.

Methods

Medical records of patients who underwent pancreatic resection for pancreatic cancer in the department of general surgery, Qilu Hospital, Shandong University were reviewed retrospectively. Demographic, clinicopathological, tumor-specific data, and histopathological reports were collected. Univariate and multivariate survival analyses were performed.

Results

A total of 83 patients with pancreatic cancer were collected. The mean number of examined LN was 8.2 ± 6.1 (0 to 26). Differential degree (low) (P = 0.019, hazard ratio (HR) = 2.276, 95% confidence interval (CI): 1.171 to 4.424) and LNR >0.2 (P = 0.018, HR = 2.685, 95% CI: 1.253 to 5.756) were independent adverse prognostic factors according to the multivariate survival analysis.

Conclusions

Our study indicated that LNR >0.2 was an independent adverse prognostic factor for pancreatic cancer, which may provide important information for prognostic assessment.

Reappraisal of Nodal Staging and Study of Lymph Node Station Involvement in Pancreaticoduodenectomy with the Standard International Study Group of Pancreatic Surgery Definition of Lymphadenectomy for Cancer

BACKGROUND

The prognostic role of lymph node (LN) dissection in pancreatic head ductal adenocarcinoma is still unclear. This study reappraised the value of the number of positive LNs and LN ratio in patients undergoing pancreaticoduodenectomy with standard lymphadenectomy according to the recent International Study Group of Pancreatic Surgery definition. In addition, the impact of nodal metastases stratified by LN stations was investigated.

STUDY DESIGN

After reviewing retrospectively clinical and pathologic data of 758 pancreaticoduodenectomies for pancreatic head ductal adenocarcinoma performed from 2002 through 2011, we extracted patients in whom the LN stations included in the International Study Group of Pancreatic Surgery definition had been sampled. Survival analysis was performed using univariate and multivariate models.

RESULTS

The study population consisted of 255 patients. Mean number of harvested LNs was 30.8. Factors with a significant prognostic impact on multivariate analysis were tumor grade, adjuvant therapy, number of positive LNs, LN metastases along station 14a-b (proximal superior mesenteric artery), and the number of metastatic LN stations. Patients with involvement of station 14a-b exhibited worse pathologic features, indicating more aggressive disease.

CONCLUSIONS

In patients receiving a uniform LN dissection, the number of positive LNs is superior to LN ratio for predicting survival. Lymph node metastases along the proximal superior mesenteric artery have a significant prognostic value, and an increasing number of metastatic stations are associated with a sharp decrease in survival. In future studies, clarification of the pattern of LN metastasis spread could offer valuable insight into the optimal treatment strategies, including selection of patients for neoadjuvant therapies.

Pancreatic adenocarcinoma with venous involvement: is up-front synchronous portal-superior mesenteric vein resection still justified? A survey of the Association Française de Chirurgie

BACKGROUND

Venous resection (VR) during pancreatectomy has been reported to neither increase mortality nor morbidity and to provide similar survival outcomes in same stage tumors. However, controversy remains regarding the indications for up-front surgery according to the degree of venous involvement.

METHODS

From 2004 to 2009, 1,399 patients included in a French multicenter survey underwent pancreaticoduodenectomy or total pancreatectomy for pancreatic adenocarcinoma, either without VR (997 standard resections [SR]) or with VR (402 patients; 29 %). Postoperative and long-term outcomes were compared in both groups.

RESULTS

VR was associated with the following factors: larger tumors (p < 0.001), poorly differentiated tumors (p = 0.004), higher numbers of positive lymph nodes (p = 0.042), and positive resection margins (R1; p < 0.001). Overall, VR increased neither postoperative morbidity nor postoperative mortality (5 vs. 3 % in SR patients; p = 0.16). The median and 3-year survival rates in VR patients versus SR patients were 21 months and 31 % vs. 29 months and 44 %, respectively (p = 0.0002). In the entire cohort, multivariate analysis identified VR as a significant poor prognostic factor for long-term survival (hazard ratio [HR] 1.75, 95 % confidence interval [CI] 1.28-2.40; p = 0.0005). In the VR patients, lymph node ratio, whatever the cutoff (<0.3: p = 0.093; ≥ 0.3: p = 0.0098), R1 resection (p = 0.010), and segmental resection (p = 0.016) were independent risk factors; neoadjuvant treatment (HR 0.52, 95 % CI 0.29-0.94; p = 0.031) and adjuvant treatment (HR 0.55, 95 % CI 0.35-0.85; p = 0.006) were significantly associated with improved long-term survival.

CONCLUSIONS

Long-term survival after pancreatectomy was significantly altered when up-front VR was performed. Neoadjuvant treatment may be a better strategy than up-front resection in patients with preoperative suspicion of venous involvement.

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

BACKGROUND

The number of lymph nodes required for accurate staging after distal pancreatectomy for pancreatic adenocarcinoma is unknown.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was used to identify 1,473 patients who underwent distal pancreatectomy for pancreatic adenocarcinoma from 1998 to 2010. We evaluated the influence of the total number of lymph nodes examined (NNE) and the lymph node ratio (LNR-positive nodes/total nodes examined) on survival.

RESULTS

The median NNE was 8. No nodes were examined in 232 (16%) of the patients, and 843 (57%) had <10 NNE. Of the patients who had at least one node examined, 612 (49%) were node positive. In the node-negative subset, the median and 5-year overall survival for patients with ≤10 NNE was significantly worse than patients with >10 NNE (16 vs. 20 months and 13 vs. 19%, respectively, p < 0.011). For node-positive patients, those with LNR ≤0.1 had better 5-year overall survival compared with LNR >0.1 (17 vs. 6%, p = 0.002).

DISCUSSION

Patients with pancreatic cancer undergoing distal pancreatectomy should ideally have at least 11 lymph nodes examined to avoid understaging. For node-positive patients, LNR may be a better prognostic indicator than the total number of positive nodes.

Neoadjuvant therapy is associated with a reduced lymph node ratio in patients with potentially resectable pancreatic cancer

BACKGROUND

The use of neoadjuvant therapy (NAC) for the treatment of potentially resectable pancreatic cancer remains controversial. In this study, we sought to evaluate cancer-specific endpoints in patients undergoing a NAC versus a surgery-first (SF) approach with specific emphasis on lymph node metastases.

METHODS

A total of 222 patients who underwent NAC and 85 patients who underwent SF were identified from 1990 to 2008 and compared for cancer-related endpoints. Peripancreatic lymph nodes from 135 neoadjuvant therapy patients were evaluated for histologic tumor regression.

RESULTS

Patients who underwent NAC followed by surgery had improved overall survival and time to local recurrence compared with the SF approach. NAC patients were less likely to have lymph node metastases (p = 0.001), lymphovascular invasion (LVI), and had smaller tumors. On multivariate analysis, lymph node positivity was associated with SF, tumor size, and the presence of LVI. NAC patients with N0 disease had equivalent outcomes to patients with a low-LNR (0.01-0.15), whereas patients with a LNR >0.15 had reduced survival, and time to local and distant recurrence. Ten of 135 (7.4 %) NAC patients had evidence of tumor regression in at least one lymph node.

CONCLUSIONS

Patients with potentially resectable PDAC selected to undergo NAC had improved survival and longer time to recurrence. Although some of these differences may be related to improvements in multimodality therapy completion rates, tumor regression in lymph node metastases exists and may demonstrate a biologic benefit of NAC compared with a SF approach.

Role of extended lymphadenectomy in the treatment of pancreatic head adenocarcinoma: review and meta-analysis

BACKGROUND

Extended lymph node dissection has been established as the method of choice in the treatment of many digestive malignancies, but its role in the treatment of adenocarcinoma of the pancreas remains controversial.

OBJECTIVES

The goal is to evaluate the role of extended lymph node dissection in pancreatic head adenocarcinoma and to review how it affects survival, morbidity, mortality and post-operative quality of life.

METHODS

A computerized search was made of the Medline database from January 1973 to October 2012. Fifteen non-duplicated studies, four randomized and 11 non-randomized, comparing extended radical pancreaticoduodenectomy (ERP) and standard pancreaticoduodenectomy were reviewed. Five-year overall survivals were compared using the MetaXL software in eight of these studies, where the necessary data were available.

RESULTS

The 5-year survival after ERP ranged from 6 to 33.4% and the local recurrence incidence from 8 to 36.1%, while the incidence of severe diarrhoea, one of the main complications, ranged from 10.8 to 42.4%. Meta-analysis showed that there was no significant difference in the 5-year overall survival (95% confidence interval (CI): -0.21-0.20, Z=0.07, P=0.94) for randomized control trials, (95% CI: -0.51-0.02, Z=1.85, P=0.07) for non-randomized control trials and (95% CI: -0.26-0.06, Z=1.20, P=0.23) for all the studies.

CONCLUSIONS

Although ERP is a safe procedure, it did not offer a significant improvement in survival, while at the same time leading to an increased incidence of severe diarrhoea for at least 1 year, thus leaving the standard pancreaticoduodenectomy as the surgical method of choice for the treatment of pancreatic head adenocarcinoma.

Definition of a standard lymphadenectomy in surgery for pancreatic ductal adenocarcinoma: a consensus statement by the International Study Group on Pancreatic Surgery (ISGPS)

BACKGROUND

The lymph node (Ln) status of patients with resectable pancreatic ductal adenocarcinoma is an important predictor of survival. The survival benefit of extended lymphadenectomy during pancreatectomy is, however, disputed, and there is no true definition of the optimal extent of the lymphadenectomy. The aim of this study was to formulate a definition for standard lymphadenectomy during pancreatectomy.

METHODS

During a consensus meeting of the International Study Group on Pancreatic Surgery, pancreatic surgeons formulated a consensus statement based on available literature and their experience.

RESULTS

The nomenclature of the Japanese Pancreas Society was accepted by all participants. Extended lymphadenectomy during pancreatoduodenectomy with resection of Ln's along the left side of the superior mesenteric artery (SMA) and around the celiac trunk, splenic artery, or left gastric artery showed no survival benefit compared with a standard lymphadenectomy. No level I evidence was available on prognostic impact of positive para-aortic Ln's. Consensus was reached on selectively removing suspected Ln's outside the resection area for frozen section. No consensus was reached on continuing or terminating resection in cases where these nodes were positive.

CONCLUSION

Extended lymphadenectomy cannot be recommended. Standard lymphadenectomy for pancreatoduodenectomy should strive to resect Ln stations no. 5, 6, 8a, 12b1, 12b2, 12c, 13a, 13b, 14a, 14b, 17a, and 17b. For cancers of the body and tail of the pancreas, removal of stations 10, 11, and 18 is standard. Furthermore, lymphadenectomy is important for adequate nodal staging. Both pancreatic resection in relatively fit patients or nonresectional palliative treatment were accepted as acceptable treatment in cases of positive Ln's outside the resection plane. This consensus statement could serve as a guide for surgeons and researchers in future directives and new clinical studies.

Prognostic factors related with survival in patients with pancreatic adenocarcinoma

The prognosis in patients with pancreatic cancer is poor and this cancer is the fourth leading cause of cancer-related death worldwide. Although surgical resection is the only curative treatment of choice for pancreatic cancer, the majority of patients are diagnosed at an advanced stage, thus only 10%-15% of them are suitable for curative resection and the overall survival is less than 5%. Chemotherapy for metastatic disease is to palliate symptoms of patients and to improve survival. Therefore, prognostic factors are important and a correct definition of poor prognostic factors may help to guide more aggressive adjuvant or aggressive treatment protocols in patients with pancreatic cancer. This article reviews the prognostic factors affecting survival of patients with pancreatic cancer in the light of recent advances in the literature.

Extended lymphadenectomy in pancreatic cancer is crucial

Lymph node metastasis is considered one of the most significant factors associated with postoperative prognosis in patients with pancreatic cancer. Some prospective studies found no significant differences in survival between patients who underwent pancreatic cancer surgery with extended lymphadenectomy and those who underwent surgery with standard lymphadenectomy. However, recent reports, such as those describing the significance of the metastatic to examined lymph node ratio, suggest the need for some degree of lymphadenectomy. This review describes the findings of published studies and discusses the usefulness of LN dissection in patients with pancreatic cancer.

Extended lymphadenectomy in patients with pancreatic cancer is debatable

Lymph node staging is one of the most important factors in determining the prognosis after resection of pancreatic ductal adenocarcinoma. Despite ongoing efforts to further refine lymph node staging, the debate on the extent of lymphadenectomy during pancreaticoduodenectomy is still open. The purpose of this review was to summarize the evidence about performing standard lymphadenectomy during curative resection of pancreatic cancer. All four prospective randomized controlled trials published concluded that extended lymphadenectomy does not contribute to better oncologic outcome for patients with adenocarcinoma of the pancreatic head. Indeed, one major drawback of extended lymphadenectomy is the higher risk of persistent postoperative diarrhea. No prospective randomized studies could be found on the role of extended lymphadenectomy in patients with adenocarcinoma of the corpus and tail. Based on current evidence there is no indication that extended lymphadenectomy should be performed routinely during resection of pancreatic cancer.

Prognostic significance of Zinc finger E-box binding homeobox 1 (ZEB1) expression in cancer cells and cancer-associated fibroblasts in pancreatic head cancer

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is characterized by an aggressive biology and poor prognosis. Experimental evidence has suggested a role for the transcriptional repressor Zinc finger E-box binding homeobox 1 (ZEB1) in epithelial-mesenchymal transition, invasion, and metastasis in PDAC. ZEB1 expression has been observed in cancer cells as well as stromal fibroblasts. Our study aimed to evaluate the prognostic value of ZEB1 expression in PDAC tissue.

METHODS

Patient baseline and follow-up data were extracted from a prospectively maintained database. After clinicopathologic re-review, serial sliced tissue slides were immunostained for ZEB1, E-cadherin, vimentin, and pan-cytokeratin. ZEB1 expression in cancer cells and adjacent stromal fibroblasts was graded separately and correlated to routine histopathologic parameters and survival after resection.

RESULTS

A total of 117 cases of PDAC were included in the study. High ZEB1 expression in cancer cells and in stromal cancer-associated fibroblasts was associated with poor prognosis. There was also a trend for poor prognosis with a lymph node ratio of greater than 0.10. In line with its role as an inducer of epithelial-mesenchymal transition, ZEB1 expression in cancer cells was positively correlated with Vimentin expression and negatively with E-Cadherin expression. In multivariate analysis, stromal ZEB1 expression grade was the only independent factor of survival after resection.

CONCLUSION

Our data suggest that ZEB1 expression in cancer cells as well as in stromal fibroblasts are strong prognostic factors in PDAC. Stromal ZEB1 expression is identified for the first time as an independent predictor of survival after resection of PDAC. This observation suggests that therapies targeting ZEB1 and its downstream pathways could hit both cancer cells and supporting cancer-associated fibroblasts.