Accuracy of Nodal Positivity in Inadequate Lymphadenectomy in Pancreaticoduodenectomy for Pancreatic Ductal Adenocarcinoma: A Population Study Using the US SEER Database

The impact of surgical-oncologic textbook outcome in patients with stage I to III pancreatic ductal adenocarcinoma: A cross-validation study of two national registries

BACKGROUND

Using national registries, we aimed to evaluate oncologic textbook outcomes in pancreatic ductal adenocarcinoma patients.

METHODS

Patients with stage I to III pancreatic ductal adenocarcinoma and surgical resection from 2010 to 2020 in the US and Germany were identified using the National Cancer Database and National Cancer Registries data. The surgical-oncologic textbook outcome was defined as complete oncologic resection with no residual tumor and ≥12 harvested lymph nodes. The composite endpoint was defined as surgical-oncologic textbook outcome and receipt of perioperative systemic and/or radiation therapy.

RESULTS

In total, 33,498 patients from the National Cancer Database and 14,589 patients from the National Cancer Registries were included. In the National Cancer Database, 28,931 (86%) patients had complete oncologic resection with no residual tumor, and 11,595 (79%) in the National Cancer Registries. 8,723 (26%) patients in the National Cancer Database and 556 (4%) in the National Cancer Registries had <12 lymph nodes harvested. The National Cancer Database shows 26,135 (78%) underwent perioperative therapy and 8,333 (57%) in the National Cancer Registries. Surgical-oncologic textbook outcome was achieved in 21,198 (63%) patients in the National Cancer Database and in 11,234 (77%) patients from the National Cancer Registries. 16,967 (50%) patients in the National Cancer Database and 7,878 (54%) patients in the National Cancer Registries had composite textbook outcome. Median overall survival in patients with composite textbook outcomes was 32 months in the National Cancer Database and 27 months in the National Cancer Registries (P < .001). In contrast, those with non-textbook outcomes had a median overall survival of 23 months in the National Cancer Database and 20 months in the National Cancer Registries (P < .001).

CONCLUSION

Surgical-oncologic textbook outcomes were achieved in > 50% of stage I to III pancreatic ductal adenocarcinoma for both the National Cancer Database and the National Cancer Registries. Failure to achieve textbook outcomes was associated with impaired survival across both registries.

Impact of Adherence to Operative Standards and Stage-Specific Guideline-Recommended Therapy in Nonmetastatic Pancreatic Adenocarcinoma

BACKGROUND

Achieving optimal surgical outcomes in pancreatic adenocarcinoma requires a combination of both curative-intent resection to oncologic standards and stage-specific neoadjuvant or adjuvant therapy. This investigation sought to examine factors associated with receipt of standard-adherent surgery (SAS) and guideline-recommended therapy (GRT) and determine the impact of compliance on patient survival.

PATIENTS AND METHODS

From the 2006-2016 National Cancer Database, 21,304 patients underwent resection for nonmetastatic pancreatic adenocarcinoma. SAS was defined as pancreatic resection with negative margins and ≥ 15 lymph nodes examined. Stage-specific GRT was defined by current National Comprehensive Cancer Network guidelines. Multivariable models were used to determine predictors of adherence to SAS and GRT and prognostic impact on overall survival.

RESULTS

Overall, SAS was achieved in 39% and GRT in 65% of patients, but only 30% received both SAS and GRT. Increasing age, minority race, uninsured status, and greater comorbidities were associated with a decreased odds of receiving both SAS and GRT (all p < 0.05). SAS (HR 0.79; CI 0.76-0.81; p < 0.001) and GRT (HR 0.67; CI 0.65-0.69; p < 0.001) were each independently associated with a survival advantage. Receipt of both SAS and GRT was associated with significant improvement in median OS compared with receiving neither (2.2 years vs 1.1 years; p < 0.001) which was independently associated with a 78% increased risk of death (HR 1.78; CI 1.70-1.86; p < 0.001).

CONCLUSIONS

Despite survival benefits associated with adherence to operative standards and receipt of guideline-recommended therapy, compliance remains poor. Future efforts must be directed toward improved education and implementation efforts around both operative standards and therapy guidelines.

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

OBJECTIVE

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

SUMMARY BACKGROUND DATA

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

METHODS

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

RESULTS

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

CONCLUSION

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

A Nomogram Based on the Log Odds of Positive Lymph Nodes Predicts the Prognosis of Patients With Distal Cholangiocarcinoma After Surgery

Background: Lymph node (LN) metastasis is considered one of the most important risk factors affecting the prognosis of distal cholangiocarcinoma (DCC). This study aimed to demonstrate the superiority of log odds of positive lymph nodes (LODDS) compared with other LN stages, and to establish a novel prognostic nomogram to predict the cancer-specific survival (CSS) of DCC.

Methods: From the Surveillance, Epidemiology and End Results (SEER) database, the data of 676 patients after DCC radical operation were screened, and patients were randomly divided into training (n = 474) and validation sets (n = 474). The prognostic evaluation performance of the LODDS and American Joint Commission on Cancer (AJCC) N stage and lymph node ratio (LNR) were compared using the Akaike information criteria, receiver operating characteristic area under the curve (AUC), and C-index. Multivariate Cox analysis was used to screen independent risk factors, and a LODDS-based nomogram prognostic staging model was established. The nomogram's precision was verified by C-index, calibration curves, and AUC, and the results were compared with those of the AJCC TNM staging system.

Results:Compared with the other two stages of LN metastasis, LODDS was most effective in predicting CSS in patients with DCC. Multivariate analysis proved that LODDS, histologic grade, SEER historic stage, and tumor size were independent risk factors for DCC. The C-index of the nomogram, based on the above factors, in the validation set was 0.663. The 1-, 3-, and 5-y AUCs were 0.735, 0.679, and 0.745, respectively. Its good performance was also verified by calibration curves. In addition, the C-index and Kaplan-Meier analysis showed that the nomogram performed better than the AJCC TNM staging system.

Conclusion:For postoperative patients with DCC, the LODDS stage yielded better prognostic efficiency than the AJCC N and LNR stages. Compared with the AJCC TNM staging system, the nomogram, based on the LODDS, demonstrated superior performance.

Time to Rethink Upfront Surgery for Resectable Intrahepatic Cholangiocarcinoma? Implications from the Neoadjuvant Experience

BACKGROUND

While surgery is a mainstay of curative-intent treatment for patients with intrahepatic cholangiocarcinoma (IHC), the role of neoadjuvant therapy (NT) has not been well-established. We sought to describe trends in NT utilization, characterize associated factors, and evaluate association with overall survival (OS).

METHODS

Retrospective cohort study of 4456 surgically resected IHC patients within National Cancer Data Base (2006-2016). NT included chemotherapy alone and/or (chemo)radiation. Descriptive statistics used to describe the cohort. Multivariable hierarchical logistic regression models were used to examine factors associated with NT administration. Analyses conducted comparing OS among upfront surgery patients and NT patients using propensity matching using nearest-neighbor methodology and adjustment using inverse probability of treatment weighting (IPTW). Association between NT and risk of death evaluated using multivariable Cox shared frailty modeling.

RESULTS

Utilization of NT did not significantly increase over time (11%-2006 to 16%-2016, trend test p = 0.07) but did increase among patients with clinical nodal involvement (cN+, 13% to 36%, p = 0.002). Factors associated with NT use include cN+ disease (odds ratio [OR] 1.68, 95% confidence interval [CI] 1.31-2.15) and advanced clinical T stage: T2 (OR 1.65, 95% CI 1.33-2.06); T3 (OR 1.51, 95% CI 1.13-2.02). After propensity matching, NT associated with a 23% decreased risk of death relative to upfront surgery (hazard ratio [HR] 0.77, 95% CI 0.61-0.97). Findings were similar after IPTW (HR 0.83, 95% CI 0.78-0.88).

CONCLUSIONS

NT is increasingly used for the management of IHC patients with characteristics indicating aggressive tumor biology and is associated with decreased risk of death. These data suggest need for prospective studies of NT in management of patients with potentially resectable IHC.

A novel prognostic nomogram for patients with surgically resected perihilar cholangiocarcinoma: a SEER-based study

Background

This study aimed to compare the predictive efficacy of four different lymph node (LN) staging systems on the overall survival (OS) of patients with surgically resected perihilar cholangiocarcinoma (pCCA), and construct a novel prognostic nomogram to predict OS in pCCA patients.

Methods

Patients with pCCA that underwent surgical resection between 2004 to 2016 were selected from the Surveillance, Epidemiology, and End Results (SEER) database (n=1,173). Patients were randomly divided into a modeling cohort and an internal verification cohort. To compare the prognostic efficacy of four different N staging systems [American Joint Committee on Cancer (AJCC) 7^th and 8^th edition N stages, lymph node ratio (LNR), and log odds of positive lymph nodes (LODDS)], we used three different evaluation methods: Harrell's index of concordance (C-index), Akaike information criterion (AIC), and area under the receiver operating characteristic (ROC) curve (AUC). Multivariate analysis was used to identify independent prognostic factors and validate LODDS in the modeling cohort. A nomogram was then constructed to predict 1-, 3-, and 5-year survival. The nomogram was validated using Harrell's C-indexes and calibration curves.

Results

Of the four different N staging methods, LODDS was considered to be the most effective LN staging system for evaluating the prognosis of patients with surgically resected pCCA, according to the values calculated for C-index, AUC, and AIC. After validation by C-indexes and calibration curves, the constructed nomogram accurately predicted the OS of pCCA patients.

Conclusions

For patients with surgically resected pCCA, LODDS was found to be the most accurate N staging system. The novel LODDS-based nomogram constructed in this study provides an accurate method for predicting patient survival in pCCA.