Time-related changes in the prognostic significance of the total number of examined lymph nodes in node-negative pancreatic head cancer

Should lymphadenectomy performed routinely in patients with primary intrahepatic cholangiocarcinoma undergoing curative hepatectomy? A retrospective cohort study with propensity-score matching analysis

BACKGROUND

The benefit of routine lymphadenectomy (LD) in improving outcomes for patients with primary intrahepatic cholangiocarcinoma (ICC) undergoing curative hepatectomy remains unclear.

MATERIALS AND METHODS

This study enrolled 269 consecutive patients who underwent liver resection for primary ICC from January 2009 to July 2020 in West China Hospital. The association of the nodal status with disease-free survival (DFS) and overall survival (OS) was analyzed using the Cox proportional hazards model and 1:1 propensity score matching (PSM) analysis.

RESULTS

Seventy-five (27.9%) patients underwent curative liver resection combined with LD (LD+ group), while 194 (72.1%) patients received curative liver resection without LD (LD- group and Nx group). Among the LD+ group, metastatic disease was present in 36 patients (48%, N1 group) and absent in 39 patients (N0 group). During the follow-up period, 116 patients (43.1%) experienced tumor recurrence and 101 patients (37.5%) died due to recurrence. Multivariate analysis revealed that lymph node metastasis (N1, HR 3.682, 95% CI 1.949-6.957, p < 0.001) was associated with worse OS, while LD+ status (HR 0.504, 95% CI 0.298-0.853, p = 0.011) was associated with improved OS. Adjuvant therapy was a protective factor for both DFS (HR 0.602, 95% CI, 0.447-0.810, p = 0.001) and OS (HR 0.683, 95% CI 0.484-0.963, p = 0.030). After 1:1 PSM, the LD+ patients (n = 74) displayed similar 1-, 3- and 5-year DFS rates (40.0, 7.9 and 7.9% vs. 29.0, 13.7 and 13.7%, p = 0.741) and OS rates (56.0, 26.6 and 22.2% vs. 58.9, 25.6, and 16.4%, p = 0.644) to the LD- patients (n = 74). Additionally, among the 75 LD+ patients, 48 patients underwent hepatic hilar lymphadenectomy (HHL), and 27 patients underwent extended hepatic hilar lymphadenectomy (EHL). Both DFS (p = 0.504) and OS (p = 0.215) were similar between the HHL and EHL groups.

CONCLUSION

Routine LD and adjuvant therapy may contribute to improved OS according to the crude analysis. LD could provide accurate staging without excessive risk and guide adjuvant therapy based on the tumor stage, potentially resulting in better survival. These results suggest that a routine LD should be considered during curative hepatectomy for ICC.

Pathologic upstaging in resected pancreatic adenocarcinoma: Risk factors and impact on survival

BACKGROUND

Clinical and pathologic staging determine treatment of pancreatic cancer. Clinical stage has been shown to underestimate final pathologic stage in pancreatic cancer, resulting in upstaging.

METHODS

National Cancer Database was used to identify clinical stage I pancreatic adenocarcinoma. Univariate, multivariable logistic regression, and Cox proportional hazard ratio were used to determine differences between upstaged and stage concordant patients.

RESULTS

Upstaging was seen in 80.2% of patients. Factors found to be significantly associated with upstaging included pancreatic head tumors (OR 2.56), high-grade histology (OR 1.74), elevated Ca 19-9 (OR 2.09), and clinical stage T2 (OR 1.99). Upstaging was associated with a 45% increased risk of mortality compared to stage concordant disease (HR 1.44, p < .001).

CONCLUSION

A majority of clinical stage I pancreatic cancer is upstaged after resection. Factors including tumor location, grade, Ca 19-9, and tumor size can help identify those at high risk for upstaging.

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.

Surgery for elderly patients with resectable pancreatic cancer, a comparison with non-surgical treatments: a retrospective study outcomes of resectable pancreatic cancer

Background

We designed a retrospective study to compare prognostic outcomes based on whether or not surgical resection was performed in elderly patients aged(≥75 years) with resectable pancreatic cancer.

Methods

We retrospectively analyzed 49 patients with resectable pancreatic cancer (surgery group, resection was performed for 38 cases; no surgery group, resection was not performed for 11 cases) diagnosed from January 2003 to December 2014 at the National Cancer Center, Korea.

Results

There was no significant difference in demographics between the two groups. The surgery group showed significantly better overall survival after diagnosis than the no surgery group (2-year survival rate, 40.7% vs. 0%; log-rank test, p = 0.015). Multivariate analysis revealed that not having undergone surgical resection [hazard ratio (HR) 2.412, P = 0.022] and a high Charlson comorbidity index (HR 5.252, P = 0.014) were independent prognostic factors for poor overall survival in elderly patients with early stage pancreatic cancer.

Conclusions

In the present study, surgical resection resulted in better prognosis than non-surgical resection for elderly patients with resectable pancreatic cancer. Except for patients with a high Charlson comorbidity index, an aggressive surgical approach seems to be beneficial for elderly patients with resectable pancreatic cancer.

ACR Appropriateness Criteria® Resectable Pancreatic Cancer

Management of resectable pancreatic adenocarcinoma continues to present a challenge due to a paucity of high-quality randomized studies. Administration of adjuvant chemotherapy is widely accepted due to the high risk of systemic spread associated with pancreatic adenocarcinoma, but the role of radiation therapy is less clear. This paper reviews literature associated with resectable pancreatic cancer to include prognostic factors to aid in the selection of patients appropriate for adjuvant therapies. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Evolution and impact of lymph node dissection during pancreaticoduodenectomy for pancreatic cancer

BACKGROUND

Insufficient examination of lymph nodes after pancreaticoduodenectomy can lead some pancreatic cancer patients with N1 disease to be misclassified as N0. We examined trends in lymph node dissection throughout time and investigated how these changes affect lymph node status and its prognostic value.

METHODS

The National Cancer Data Base was queried for patients with nonmetastatic pancreatic adenocarcinoma (2004-2013) who underwent classic pancreaticoduodenectomy with antrectomy. Logistic regression was performed for odds of node positivity. Kaplan-Meier curves and Cox proportional hazards models were used to assess the impact of lymph node status on overall survival for patients diagnosed during 2-year intervals from 2004-2012.

RESULTS

Median number of examined lymph nodes was 10 (interquartile range 6-15) in 2004 vs 17 (interquartile range 12-24) in 2013. Number of lymph nodes examined was a significant predictor of N1 disease (P < .0001), with a plateau at 30 nodes. N1 disease increased from 64.4% to 68.0% (P < .0001). Survival for both N1 and N0 subgroups improved. In successive multivariate models, N0 versus N1 status was consistently protective for overall survival (P < .0001), but there was no change in the magnitude of its hazard ratio over time (overall hazard ratio 0.691; 95% confidence interval 0.660-0.723).

CONCLUSION

Contemporary patients have an adequate number of nodes examined during standard pancreaticoduodenectomy. This, along with rising rates of N1 cancer detection and improved survival for both node-positive and node-negative patients, suggest more accurate classification of lymph node status. However, no increased benefit is achieved beyond 30 nodes. Overall, lymph node status remains a strong prognosticator for overall survival.

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.

Defining the possible therapeutic benefit of lymphadenectomy among patients undergoing hepatic resection for intrahepatic cholangiocarcinoma

BACKGROUND

The aim of the study was to investigate the therapeutic role of lymphadenectomy (LND) in patients with intrahepatic cholangiocarcinoma.

METHODS

826 patients who underwent liver resection were identified using the SEER database from 1988 to 2011. Two groups of patients were defined: 201 (24%) undergoing potentially therapeutic LND (group A, >3 lymph nodes (LN) removed), and 625 (76%) not receiving therapeutic LND (group B, ≤3 LNs removed). A propensity score analysis was performed to create a matched cohort of 402 patients (201 in either group). The survival benefit of therapeutic LND was also estimated using multivariate parametric analysis comparing two simulated cohorts of 826 patients.

RESULTS

1-, 3-, and 5-year survival rates were 71%, 37%, and 27% for group A patients, and 73%, 37%, and 27% for matched group B patients (P = 0.656). When simulation analysis was performed, a moderate survival benefit of LND of 5.46 months was calculated (95%CI, 4.64-6.29). Considerable differences in LND survival benefit predictions were found according to patient's sex (males, 9.90 vs. females 1.16 months), age (≤60 years, 15 vs. >60 years, -1.34 months), and tumor size (>50 mm, 9.20 vs. ≤50 mm, -0.28).

CONCLUSIONS

LND therapeutic benefit among a subset of patients. Future work is required to investigate the role of routine LND among these patients. J. Surg. Oncol. 2016;113:685-691. © 2016 Wiley Periodicals, Inc.

Perihilar Cholangiocarcinoma: Number of Nodes Examined and Optimal Lymph Node Prognostic Scheme

BACKGROUND

The role of routine lymphadenectomy for perihilar cholangiocarcinoma is still controversial and no study has defined the minimum number of lymph nodes examined (TNLE). We sought to assess the prognostic performance of American Joint Committee on Cancer/Union Internationale Contre le Cancer (7(th) edition) N stage, lymph node ratio, and log odds (LODDS; logarithm of the ratio between metastatic and nonmetastatic nodes) in patients with perihilar cholangiocarcinoma and identify the optimal TNLE to accurately stage patients.

METHODS

A multi-institutional database was queried to identify 437 patients who underwent hepatectomy for perihilar cholangiocarcinoma between 1995 and 2014. The prognostic abilities of the lymph node staging systems were assessed using the Harrell's c-index. A Bayesian model was developed to identify the minimum TNLE.

RESULTS

One hundred and fifty-eight (36.2%) patients had lymph node metastasis. Median TNLE was 3 (interquartile range, 1 to 7). The LODDS had a slightly better prognostic performance than lymph node ratio and American Joint Committee on Cancer, in particular among patients with <4 TNLE (c-index = 0.568). For 2 TNLE, the Bayesian model showed a poor discriminatory ability to distinguish patients with favorable and poor prognosis. When TNLE was >2, the hazard ratio for N1 patients was statistically significant and the hazard ratio for N1 patients increased from 1.51 with 4 TNLE to 2.10 with 10 TNLE. Although the 5-year overall survival of N1 patients was only slightly affected by TNLE, the 5-year overall survival of N0 patients increased significantly with TNLE.

CONCLUSIONS

Perihilar cholangiocarcinoma patients undergoing radical resection should ideally have at least 4 lymph nodes harvested to be accurately staged. In addition, although LODDS performed better at determining prognosis among patients with <4 TNLE, both lymph node ratio and LODDS outperformed compared with American Joint Committee on Cancer N stage among patients with ≥4 TNLE.

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.

Lymph node evaluation for treatment of adenocarcinoma of the pancreas

BACKGROUND

Increased lymph node evaluation has been associated with improved survival rates in patients with pancreatic cancer. We sought to evaluate the trends and factors associated with lymph node examination over time and the effects on survival.

METHODS

Using the Surveillance, Epidemiology and End Results database, we conducted an analysis of adults with adenocarcinoma of the pancreas who underwent surgical resection. Using the Cochrane Armitage test for trend and logistic regression we identified factors associated with lymph node evaluation. Kaplan-Meier and Cox proportional hazards modeling were used to examine survival.

RESULTS

We identified 4831 patients who underwent surgical resection from 1990 to 2010. The proportion of patients with 15 or more lymph nodes evaluated increased from 16% to 42% (p < 0.05) and the median number of lymph nodes examined increased from 7 to 15 nodes (p < 0.05) during the study period. Overall, 56% of patients had lymph node metastases; this proportion significantly increased during the study period. Factors that were independently associated with less than 15 lymph nodes evaluated included male gender, receipt of pre-operative radiation therapy, early year of diagnosis, older age, and missing information on tumor grade and size (p < 0.05). Survival rates significantly improved when 15 or more lymph nodes were examined.

CONCLUSION

We observed a significant increase in the number of lymph nodes evaluated with pancreas cancer resection over time. Lymph node evaluation was significantly associated with patient, tumor, and treatment characteristics. Our results suggest that adequate lymph node evaluation is associated with improved survival.

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.