Lymph node status after resection for gallbladder adenocarcinoma: prognostic implications of different nodal staging/scoring systems

Interpretable machine learning-based clinical prediction model for predicting lymph node metastasis in patients with intrahepatic cholangiocarcinoma

OBJECTIVE

Prediction of lymph node metastasis (LNM) for intrahepatic cholangiocarcinoma (ICC) is critical for the treatment regimen and prognosis. We aim to develop and validate machine learning (ML)-based predictive models for LNM in patients with ICC.

METHODS

A total of 345 patients with clinicopathological characteristics confirmed ICC from Jan 2007 to Jan 2019 were enrolled. The predictors of LNM were identified by the least absolute shrinkage and selection operator (LASSO) and logistic analysis. The selected variables were used for developing prediction models for LNM by six ML algorithms, including Logistic regression (LR), Gradient boosting machine (GBM), Extreme gradient boosting (XGB), Random Forest (RF), Decision tree (DT), Multilayer perceptron (MLP). We applied 10-fold cross validation as internal validation and calculated the average of the areas under the receiver operating characteristic (ROC) curve to measure the performance of all models. A feature selection approach was applied to identify importance of predictors in each model. The heat map was used to investigate the correlation of features. Finally, we established a web calculator using the best-performing model.

RESULTS

In multivariate logistic regression analysis, factors including alcoholic liver disease (ALD), smoking, boundary, diameter, and white blood cell (WBC) were identified as independent predictors for LNM in patients with ICC. In internal validation, the average values of AUC of six models ranged from 0.820 to 0.908. The XGB model was identified as the best model, the average AUC was 0.908. Finally, we established a web calculator by XGB model, which was useful for clinicians to calculate the likelihood of LNM.

CONCLUSION

The proposed ML-based predicted models had a good performance to predict LNM of patients with ICC. XGB performed best. A web calculator based on the ML algorithm showed promise in assisting clinicians to predict LNM and developed individualized medical plans.

Application of laparoscopic surgery in gallbladder carcinoma

Gallbladder carcinoma (GC) is a rare type of cancer of the digestive system, with an incidence that varies by region. Surgery plays a primary role in the comprehensive treatment of GC and is the only known cure. Compared with traditional open surgery, laparoscopic surgery has the advantages of convenient operation and magnified field of view. Laparoscopic surgery has been successful in many fields, including gastrointestinal medicine and gynecology. The gallbladder was one of the first organs to be treated by laparoscopic surgery, and laparoscopic cholecystectomy has become the gold standard surgical treatment for benign gallbladder diseases. However, the safety and feasibility of laparoscopic surgery for patients with GC remain controversial. Over the past several decades, research has focused on laparoscopic surgery for GC. The disadvantages of laparoscopic surgery include a high incidence of gallbladder perforation, possible port site metastasis, and potential tumor seeding. The advantages of laparoscopic surgery include less intraoperative blood loss, shorter postoperative hospital stay, and fewer complications. Nevertheless, studies have provided contrasting conclusions over time. In general, recent research has tended to support laparoscopic surgery. However, the application of laparoscopic surgery in GC is still in the exploratory stage. Here, we provide an overview of previous studies, with the aim of introducing the application of laparoscopy in GC.

Predictors, Patterns, and Impact of Adequate Lymphadenectomy in Intrahepatic Cholangiocarcinoma

INTRODUCTION

Despite lymph node metastases (LNMs) being associated with worse survival, adequate lymph node evaluation (LNE) has not been universally adopted for intrahepatic cholangiocarcinoma (ICC). We sought to evaluate trends in LNE, predictors of LNE and LNM, as well as the role of adequate lymphadenectomy in stratifying patients relative to survival.

METHODS

Patients who underwent curative-intent liver resection for ICC (2010-2019) were identified from the National Cancer Database and stratified according to LNE: 0, 1-5 (inadequate lymphadenectomy) and ≥6 (adequate lymphadenectomy). Multivariate logistic regression was utilized to assess predictors of LNE and LNM. Overall survival and receipt of adequate lymphadenectomy were assessed relative to LNM and log-odds of lymph nodes (LODDS).

RESULTS

Among 6507 patients, adequate lymphadenectomy was performed in only 1118 (17.2%) patients, although compliance with adequate lymphadenectomy increased over time (2010-2012: 14.2% vs. 2016-2019: 18.9%; p < 0.001). After controlling for relevant factors, region (reference: Northeast; Midwest: odds ratio [OR] 1.90, 95% confidence interval [CI] 1.48-2.44; South: OR 1.64, 95% CI 1.28-2.10; West: OR 1.83, 95% CI 1.37-2.44) and preoperative nodal status (reference: cN0; cNx: OR 2.18, 95% CI 1.68-2.95; cN1: OR 3.88, 95% CI 3.02-4.98) strongly predicted adequate lymphadenectomy. Furthermore, adequate lymphadenectomy resulted in higher odds of detecting ≥1 LNMs (OR 2.63, 95% CI 2.25-3.08), regardless of preoperative nodal status. Adequate lymphadenectomy demonstrated an improved ability to stratify patients relative to 5-year survival based on LNM (N0: 51.3% vs. N1: 30.6% vs. N2: 13.7%; p < 0.001) and LODDS (LODDS1: 50.7% vs. LODDS2: 27.4% vs. LODDS3: 15.7%; p < 0.001).

CONCLUSIONS

Compliance with adequate lymphadenectomy at the time of surgery for ICC remains suboptimal with marked regional variations. Adequate lymphadenectomy was associated with higher odds of detecting LNM and improved survival stratification relative to both LNM and LODDS. Greater emphasis on nodal evaluation is required to ensure optimal management of ICC.

N, LNR or LODDS: Which Is the Most Appropriate Lymph Node Classification Scheme for Patients with Radically Resected Pancreatic Cancer?

Simple Summary

To date, no data are available regarding the most appropriate alternative LN classification system with respect to prognostic power and discriminative ability in cases with resectable pancreatic ductal adenocarcinoma (PDAC). We compared different lymph node classification systems with regard to accurate evaluation of overall survival in 319 patients with resected PDAC. One LNR and one LODDS classification scheme were found to out-perform the N category in distinct patient subgroups. Only the LODDS classification exhibited statistically significant, gradually increasing HRs of their subcategories and, at the same time, significantly better discriminative potential in the subgroups of patients with PDAC of the head or corpus and in patients with tumor-free resection margins or M0 status, respectively.

Abstract

Background: Even though numerous novel lymph node (LN) classification schemes exist, an extensive comparison of their performance in patients with resected pancreatic ductal adenocarcinoma (PDAC) has not yet been performed. Method: We investigated the prognostic performance and discriminative ability of 25 different LN ratio (LNR) and 27 log odds of metastatic LN (LODDS) classifications by means of Cox regression and C-statistic in 319 patients with resected PDAC. Regression models were adjusted for age, sex, T category, grading, localization, presence of metastatic disease, positivity of resection margins, and neoadjuvant therapy. Results: Both LNR or LODDS as continuous variables were associated with advanced tumor stage, distant metastasis, positive resection margins, and PDAC of the head or corpus. Two distinct LN classifications, one LODDS and one LNR, were found to be superior to the N category in the complete patient collective. However, only the LODDS classification exhibited statistically significant, gradually increasing HRs of their subcategories and at the same time significantly higher discriminative potential in the subgroups of patients with PDAC of the head or corpus and in patients with tumor free resection margins or M0 status, respectively. On this basis, we built a clinically helpful nomogram to estimate the prognosis of patients after radically resected PDAC. Conclusion: One LNR and one LODDS classification scheme were found to out-perform the N category in terms of both prognostic performance and discriminative ability, in distinct patient subgroups, with reference to OS in patients with resected PDAC.

Prognostic Performance of Alternative Lymph Node Classification Systems for Patients with Medullary Thyroid Cancer: A Single Center Cohort Study

BACKGROUND

Lymph node ratio (LNR) and the log odds of positive lymph nodes (LODDS) have been proposed as alternative lymph node (LN) classification schemes. Various cut-off values have been defined for each system, with the question of the most appropriate for patients with medullary thyroid cancer (MTC) still remaining open. We aimed to retrospectively compare the predictive impact of different LN classification systems and to define the most appropriate set of cut-off values regarding accurate evaluation of overall survival (OS) in patients with MTC.

METHODS

182 patients with MTC who were operated on between 1985 and 2018 were extracted from our medical database. Cox proportional hazards regression models and C-statistics were performed to assess the discriminative power of 28 LNR and 28 LODDS classifications and compare them with the N category according to the 8th edition of the AJCC/UICC TNM classification in terms of discriminative power. Regression models were adjusted for age, sex, T category, focality, and genetic predisposition.

RESULTS

High LNR and LODDS are associated with advanced T categories, distant metastasis, sporadic disease, and male gender. In addition, among 56 alternative LN classifications, only one LNR and one LODDS classification were independently associated with OS, regardless of the presence of metastatic disease. The C-statistic demonstrated comparable results for all classification systems showing no clear superiority over the N category.

CONCLUSION

Two distinct alternative LN classification systems demonstrated a better prognostic performance in MTC patients than the N category. However, larger scale studies are needed to further verify our findings.

Optimal Lymph Node Staging System in Evaluating Prognosis of Gallbladder Carcinoma: A Multi-institutional Study

BACKGROUND

Lymph node (LN) involvement is a critical prognostic factor in patients with gallbladder carcinoma (GBC). Controversy exists regarding optimal categorization of nodal metastasis status, including anatomical location of positive nodes (AJCC 7th N staging), number of metastatic lymph nodes (NMLN), log odds of metastatic LNs (LODDS), and lymph node ratio (LNR).

METHODS

Patients who underwent curative-intent resection for GBC from six Chinese tertiary hospitals between 2008 and 2013 were analyzed retrospectively. The relative discriminative abilities of the different LN staging systems were assessed by different models including the tree-augmented naïve Bayesian (TAN) model, Cox proportional hazards regression model, and binary logistic regression model.

RESULTS

A total of 226 patients were involved in this cohort. Based on the TAN model and composite importance measures, the most important factor affecting the prognosis in the different LN staging systems was NMLN. Among the four TAN models which were built with 4 metastatic LN markers and baseline variables, the accuracy of the NMLN-based prognostic model was 88.15%, higher than 7th N staging (86.44%), LNR (87.34%), and LODDS (85.19%). The Cox model based on NMLN (C-index: 0.763, AIC: 1371.62) had a higher fitness than the others (7th N staging C-index: 0.756, AIC: 1375.51; LNR C-index: 0.759, AIC: 1378.82; LODDS C-index 0.748, AIC: 1390.99). The AUCs of different staging binary logistic regression models were NMLN (0.872), LNR (0.872), 7th N staging (0.869) and LODDS (0.856), respectively.

CONCLUSIONS

NMLN was the optimal LN staging system in evaluating prognosis of GBC.

Construction and Validation of a Nomogram Based on the Log Odds of Positive Lymph Nodes to Predict the Prognosis of Medullary Thyroid Carcinoma After Surgery

BACKGROUND

This study aimed to explore the prognostic impact that the log odds of positive lymph nodes (LODDS) has on medullary thyroid cancer (MTC) and to develop a nomogram incorporating LODDS to predict the cancer-specific survival (CSS) of MTC.

METHODS

Data from 1110 MTC patients after total thyroidectomy were collected from the Surveillance, Epidemiology, and End Results (SEER) database and divided into training and validation cohorts. The prognostic efficiency of N status from the American Joint Committee on Cancer (AJCC) staging system, the number of positive lymph nodes (PLNN), and LODDS were compared using the Harrell concordance index (C-index), the Akaike information criterion (AIC), and area under the receiver operating characteristic (ROC) curve (AUC). A multivariate Cox analysis was performed to determine the independent prognostic factors, and a nomogram based on LODDS was constructed. The nomogram's performance was assessed with the C-index, AUC, calibration curves, and decision curve analysis (DCA).

RESULTS

Among the three lymph node (LN) staging systems, LODDS showed the highest accuracy in predicting CSS for MTC. In the training cohort, the C-index of the LODDS-based nomogram was 0.895. The AUCs were 0.949, 0.917, 0.925, and 0.901 for predicting 1-, 3-, 5- and 10-year CSS, respectively. The calibration plots and DCA showed the superior clinical applicability of the nomogram. These results were verified in the validation cohort.

CONCLUSIONS

As an independent prognostic factor for MTC, LODDS demonstrated superior prognostic efficiency over N status and PLNN. This LODDS-based nomogram yielded better performance than the AJCC tumor-node-metastasis (TNM) staging system in predicting CSS after surgery for MTC.

Clinicopathological Differences in T2 Gallbladder Cancer According to Tumor Location

We aimed to identify clinicopathological differences and factors affecting survival outcomes of stage T2a and T2b gallbladder cancer (GBC) and validate the oncological benefits of regional lymphadenectomy and hepatic resection in these patients. This single-center study enrolled patients who were diagnosed with pathologically confirmed T2 GBC and underwent curative resection between January 1995 and December 2017. Eighty-two patients with T2a and 50 with T2b GBCs were identified, and clinical information was retrospectively collected from medical records and analyzed. Five-year overall survival rates were 96.8% and 80.7% in T2a and T2b groups, respectively (P = .007). Three- and 5-year survival rates among all patients with T2 GBC without and with lymph node metastasis were 97.2% and 94.4% and 81.3% and 81.3%, respectively (P = .029). There was no difference in survival rates between the 2 groups according to whether hepatic resection was performed (P = .320). However, in the T2b group, those who underwent hepatic resection demonstrated a better survival rate than those who did not (P = .029). The T2b group had more multiple recurrence patterns than the T2a group, and the lymph nodes were the most common site in both groups. Multivariate analysis revealed that lymph node metastasis, vascular invasion, and tumor location were significant independent prognostic factors. Hepatic resection was not always necessary in patients with peritoneal-side GBC. Considering clinicopathological features and recurrence patterns, a systematic treatment plan, including radical resection and adjuvant treatment, should be established for hepatic-side GBC.

Examination of Prognostic Factors Affecting Long-Term Survival of Patients with Stage 3/4 Gallbladder Cancer without Distant Metastasis

In advanced gallbladder cancer (GBC) radical resection, if multiple prognostic factors are present, the outcome may be poor; however, the details remain unclear. To investigate the poor prognostic factors affecting long-term surgical outcome, we examined 157 cases of resected stage 3/4 GBC without distant metastasis between 1985 and 2017. Poor prognostic factors for overall survival and treatment outcomes of a number of predictable preoperative poor prognostic factors were evaluated. The surgical mortality was 4.5%. In multivariate analysis, blood loss, poor histology, liver invasion, and ≥4 regional lymph node metastases (LNMs) were independent prognostic factors for poor surgical outcomes; invasion of the left margin or the entire area of the hepatoduodenal ligament and a Clavien–Dindo classification ≥3 were marginal factors. The analysis identified outcomes of patients with factors that could be predicted preoperatively, such as liver invasion ≥5 mm, invasion of the left margin or the entire area of the hepatoduodenal ligament, and ≥4 regional LNMs. Thus, the five-year overall survival was 54% for zero factors, 34% for one factor, and 4% for two factors (p < 0.05). A poor surgical outcome was likely when two or more factors were predicted preoperatively; therefore, new treatment strategies are required for such patients.

Comparison of lymph node evaluation and yield among patients undergoing open and minimally invasive surgery for gallbladder adenocarcinoma

INTRODUCTION

Assessment of regional lymph nodes (LN) is essential for determining prognosis among patients with gallbladder cancer (GBC). The impact of surgical technique on LN yield has not been well explored. We investigated the impact of minimally invasive surgery (MIS; robotic or laparoscopic) on the evaluation and retrieval of regional LN for patients with GBC.

METHODS

We queried the National Cancer Database (NCDB) to identify patients with GBC who underwent curative-intent surgery between 2010 and 2015. Patients with metastatic disease or those with missing data on surgical resection or LN evaluation were excluded.

RESULTS

We identified 2014 patients who underwent an open (n = 1141, 56.6%) or MIS approach (n = 873, 43.4%) for GBC and met the inclusion criteria. Patients who underwent MIS were older (open: 68 years, IQR: 60, 75 vs. MIS: 70 years, IQR (61, 77); P = 0.02), and were more commonly treated at a comprehensive community cancer program (P < 0.001). Approximately 3 out of 4 patients (n = 1468, 72.9%) underwent an evaluation of regional LN, with nearly half of these patients (n = 607, 41.7%) having LN metastasis. Among patients who underwent a regional lymphadenectomy, average lymph node yield was 3 (IQR: 1, 6) and was similar between the two groups (P = 0.04). After controlling for all factors, operative approach was not associated with likelihood of receiving a lymphadenectomy during curative-intent resection (OR 0.81, 95% CI 0.63-1.04; P = 0.11).

CONCLUSION

In conclusion, patients undergoing curative-intent resection for GBC had similar rates of lymph node evaluation and yield regardless of operative approach. Over one-quarter of patients did not undergo a lymphadenectomy at the time of surgery. Further studies are needed to identify barriers to lymph node evaluation and yield among patients undergoing surgery for gallbladder cancer. Presented at the 2019 2nd World Congress of the International Laparoscopic Liver Society, Tokyo, Japan.

Validation of the 8th Edition of the American Joint Committee on Cancer Staging System for Gallbladder Cancer and Implications for the Follow-up of Patients without Node Dissection

PURPOSE

The 8th edition of gallbladder cancer staging in the American Joint Committee on Cancer (AJCC) staging system changed the T and N categories.

MATERIALS AND METHODS

In order to validate the new staging system, a total of 348 surgically resected gallbladder cancers were grouped based on the 8th edition of the T and N categories and compared with patients' survival.

RESULTS

Significant differences were noted between T1b-T2a (p=0.003) and T2b-T3 (p < 0.001) tumors, but not between Tis-T1a, T1a-T1b, and T2a-T2b tumors. However, significant survival differences were observed both by the overall and pair-wise (T1-T2, T2-T3) comparisons (all, p < 0.001) without dividing T1/T2 subcategories. When cases with ≥ 6 examined lymph nodes were evaluated, significant survival differences were observed among the entire comparison (p < 0.001) and pair-wise comparisons of N0-N1 (p=0.001) and N1-N2 (p=0.039) lesions. When cases without nodal dissection (NX) were additionally compared, significant survival differences were observed between patients with N0-NX (p=0.001) and NX-N1 (p < 0.001) lesions.

CONCLUSION

The T category in the 8th edition of the AJCC staging system did not completely stratify the prognosis of patients with gallbladder cancer. Modification by eliminating T subcategories can better stratify the prognosis. In contrast, the N category clearly determines patients' survival with ≥ 6 examined lymph nodes. The survival time in patients of gallbladder cancers without nodal dissection is between N0 and N1 cases. Therefore, close postoperative followed up is recommended for those patients.

Hippo-YAP1 Is a Prognosis Marker and Potentially Targetable Pathway in Advanced Gallbladder Cancer

Gallbladder cancer is an aggressive disease with late diagnosis and no efficacious treatment. The Hippo-Yes-associated protein 1 (YAP1) signaling pathway has emerged as a target for the development of new therapeutic interventions in cancers. However, the role of the Hippo-targeted therapy has not been addressed in advanced gallbladder cancer (GBC). This study aimed to evaluate the expression of the major Hippo pathway components mammalian Ste20-like protein kinase 1 (MST1), YAP1 and transcriptional coactivator with PDZ-binding motif (TAZ) and examined the effects of Verteporfin (VP), a small molecular inhibitor of YAP1-TEA domain transcription factor (TEAD) protein interaction, in metastatic GBC cell lines and patient-derived organoids (PDOs). Immunohistochemical analysis revealed that advanced GBC patients had high nuclear expression of YAP1. High nuclear expression of YAP1 was associated with poor survival in GBC patients with subserosal invasion (pT2). Additionally, advanced GBC cases showed reduced expression of MST1 compared to chronic cholecystitis. Both VP treatment and YAP1 siRNA inhibited the migration ability in GBC cell lines. Interestingly, gemcitabine resistant PDOs with high nuclear expression of YAP1 were sensitive to VP treatment. Taken together, our results suggest that key components of the Hippo-YAP1 signaling pathway are dysregulated in advanced gallbladder cancer and reveal that the inhibition YAP1 may be a candidate for targeted therapy.

A new nomogram from the SEER database for predicting the prognosis of gallbladder cancer patients after surgery

Background

To study the prognostic significance in gallbladder cancer (GBC) patients of the four N stage methods of log odds of positive lymph nodes (LODDS), lymph node ratio (LNR), and N stage in the 7th and 8^th editions of the American Joint Committee on Cancer (AJCC), and to establish a prognostic model of GBC based on LODDS.

Methods

Data of 1,321 patients with GBC who underwent surgical resection of lymph nodes from 2010 to 2014 were collected from the Surveillance, Epidemiology, and End Results (SEER) database. We then randomly divided these data into a training set (n=925) and a validation set (n=396). C-index, Akaike information criterion (AIC), and area under the curve (AUC) were calculated to evaluate the accuracy of LODDS, LNR, and N stage in the 7^th and 8^th editions of the AJCC. Cox multivariate analysis was performed to determine whether LODDS was an independent prognostic factor, and a nomogram model was established. C-index was used to evaluate the accuracy of the nomogram. A receiver operating characteristic (ROC) curve was drawn and the area under the AUC was calculated to evaluate the accuracy of the nomogram in predicting patients' 1-, 3-, and 5-year overall survival (OS).

Results

Univariate analysis showed that the four methods were all correlated with OS. Through C-index, AIC and AUC, We found that LODDS had the best accuracy of the four methods. C-index and AUC analysis revealed that the nomogram based on LODDS had excellent prognostic ability. All the results were verified in the validation set.

Conclusions

LODDS is an independent prognostic factor for GBC patients, and it is the best N stage in the SEER database. This new nomogram-containing LODDS system is a great model to predict the prognosis of GBC patients.

Modified staging classification of gallbladder carcinoma on the basis of the 8th edition of the American Joint Commission on Cancer (AJCC) staging system

PURPOSE

The 8th edition of the American Joint Commission on Cancer (AJCC) Staging System for gallbladder cancer (GBC) has been used in clinical practice, but we have found some deficiencies in this edition.

METHODS

Survival analyses were performed to evaluate the application of various editions of the AJCC staging systems using the Surveillance, Epidemiology, and End Results (SEER) database (N = 9616 patients) and Fudan University Zhongshan Hospital (FUZH) database (N = 327 patients). A modified staging system was proposed based on the 8th edition of the AJCC Staging System.

RESULTS

Although all N2 diseases were grouped into stage IVB as M1 in the 8th edition, some patients with N2 diseases could undergo R0 resection, and had longer survival than patients with M1 diseases had in both cohorts (p < 0.001 in SEER, p = 0.041 in FUZH). Furthermore, in the SEER database, stage IIIA patients aberrantly had poorer survival than stage IIIB patients had (p < 0.001). Therefore, we proposed a modified staging system by rearranging the substages. N2 disease was subdivided and reappraised according to T stage, and the aberrant survival reversal of stage IIIA and stage IIIB disease was also corrected. Through our modification, the C-index of the 8th AJCC Staging System was elevated from 0.596 [95% confidence interval (CI): 0.585-0.607] to 0.623 (95% CI: 0.612-0.634) for local disease in the SEER cohort. Similar findings were also observed in the FUZH cohort.

CONCLUSION

Our modified 8th AJCC Staging System is more suitable for GBC and could be adopted for clinical practice.

Systematic review of management of incidental gallbladder cancer after cholecystectomy

BACKGROUND

Gallbladder cancer is rare, but cancers detected incidentally after cholecystectomy are increasing. The aim of this study was to review the available data for current best practice for optimal management of incidental gallbladder cancer.

METHODS

A systematic PubMed search of the English literature to May 2018 was conducted.

RESULTS

The search identified 12 systematic reviews and meta-analyses, in addition to several consensus reports, multi-institutional series and national audits. Some 0·25-0·89 per cent of all cholecystectomy specimens had incidental gallbladder cancer on pathological examination. Most patients were staged with pT2 (about half) or pT1 (about one-third) cancers. Patients with cancers confined to the mucosa (T1a or less) had 5-year survival rates of up to 100 per cent after cholecystectomy alone. For cancers invading the muscle layer of the gallbladder wall (T1b or above), reresection is recommended. The type, extent and timing of reresection remain controversial. Observation time may be used for new cross-sectional imaging with CT and MRI. Perforation at initial surgery had a higher risk of disease dissemination. Gallbladder cancers are PET-avid, and PET may detect residual disease and thus prevent unnecessary surgery. Routine laparoscopic staging before reresection is not warranted for all stages. Risk of peritoneal carcinomatosis increases with each T category. The incidence of port-site metastases is about 10 per cent. Routine resection of port sites has no effect on survival. Adjuvant chemotherapy is poorly documented and probably underused.

CONCLUSION

Management of incidental gallbladder cancer continues to evolve, with more refined suggestions for subgroups at risk and a selective approach to reresection.

Prognostic validation of the updated 8th edition Tumor-Node-Metastasis classification by the Union for International Cancer Control: Survival analyses of 307 patients with surgically treated gallbladder carcinoma

In December 2016, the Union for International Cancer Control (UICC) published the 8th edition of the Tumor-Node-Metastasis (TNM) classification of malignant tumors, including a number of vital changes in the definitions of the T2 category, the N category and the stages of gallbladder cancer (GBC). The clinical value of this newly updated classification in patients with surgically treated GBC has not been rigorously validated. The present study aimed to analyze the prognosis of patients with GBC in a high-volume surgical unit, and to validate the prognostic value of the new UICC TNM classification, particularly the main changes in the stages of GBC. Data from 307 patients who were surgically treated and histopathologically diagnosed with GBC between January 2011 and July 2016 in The West China Hospital (Chengdu, Sichuan, China) were retrospectively collected and analyzed. The new UICC criteria distributed 32, 60, 99 and 116 eligible patients in stages I, II, III and IV, respectively. The differences in overall survival time between each stage (I–IV) demonstrated statistical significance (P<0.05). As a result of the main change of this classification, the novel definitions of T2a and T2b effectively stratified the prognosis of patients with T2 GBC (P<0.001). Furthermore, patients with stage IIa tumors also obtained significantly improved overall survival time compared with patients with stage IIb tumors (P=0.04), whereas the comparison between patients with stage IIb and IIIa tumors did not present any notable difference (P=0.20). Additionally, the new N category stratified the survival of the patients effectively (P<0.001). Together with curative resection, this latest classification was indicated to be an independent predictor of survival via multivariate analysis (hazard ratio, 6.25; 95% confidence interval, 3.81–10.26; P<0.001). In conclusion, the newly updated UICC TNM classification could effectively reflect the clinical outcome of patients with surgically treated GBC. Furthermore, tumor location could predict the survival of surgically treated T2 GBC. The novel classification of the N category by the number of lymph nodes involved was also demonstrated to be valid.

Surgical management of periampullary adenocarcinoma: defining an optimal prognostic lymph node stratification schema

Background: Lymph node (LN) metastasis is a strong predictor of unfavorable prognosis for patients with periampullary adenocarcinoma after surgical resection. We sought to assess the prognostic performance of several LN staging systems, including American Joint Committee on Cancer (AJCC)/ International Union Against Cancer (7th edition) N stage, the total number of LN (TLN), the number of metastatic LN (MLN), the lymph node ratio (LNR) and the log odds of MLNs (LODDS), in patients with periampullary adenocarcinoma after surgical resection and identify the optional LN staging system to accurately stratify patients with different prognoses. Methods: We retrospectively analyzed 205 patients with periampullary adenocarcinoma after surgical resection. The predictive effects of several LN staging systems on overall survival (OS) and progression free survival (PFS) for all included patients and patients with more than 12 TLNs examined were evaluated and compared using the time-dependent receive operating characteristic (ROC) curve and decision curve analysis (DCA), respectively. Results: Eighty-nine patients (43.4%) had LN metastasis and their survival was not significantly decreased compared with patients without LN metastasis. LODDS and LNR were able to stratify patients into various subgroups with significant differences of both OS and PFS. When assessed using ROC curve and DCA, LODDS outperformed LNR and other LN staging systems in predicting OS and PFS. In addition, when analyzed in patients with more than 12 TLNs examined, LODDS had a higher value of area under ROC curve (AUC) and showed better performance of DCA. Conclusion: LODDS performs better than other LN staging systems in predicting OS and PFS for patients with periampullary adenocarcinoma after surgical resection. Adequate LN dissection is necessary for curative surgery, as well as to achieve a more accurate staging of the disease and a more precise prediction of survival for these patients.

Defining the Chance of Statistical Cure Among Patients with Extrahepatic Biliary Tract Cancer

BACKGROUND

While surgery offers the best curative-intent treatment, many patients with biliary tract malignancies have poor long-term outcomes. We sought to apply a non-mixture cure model to calculate the cure fraction and the time to cure after surgery of patients with peri-hilar cholangiocarcinoma (PHCC) or gallbladder cancer (GBC).

METHODS

Using the Extrahepatic Biliary Malignancy Consortium, 576 patients who underwent curative-intent surgery for gallbladder carcinoma or peri-hilar cholangiocarcinoma between 1998 and 2014 at 10 major hepatobiliary institutions were identified and included in the analysis. A non-mixture cure model was adopted to compare mortality after surgery to the mortality expected for the general population matched by sex and age.

RESULTS

The median and 5-year overall survival (OS) were 1.9 years (IQR, 0.9-4.9) and 23.9 % (95 % CI, 19.6-28.6). Among all patients with PHCC or GBC, the probability of being cured after surgery was 14.5 % (95 % CI, 8.7-23.2); the time to cure was 9.7 years and the median survival of uncured patients was 1.8 years. Determinants of cure probabilities included lymph node metastasis and CA 19.9 level (p ≤ 0.05). The cure fraction for patients with a CA 19.9 < 50 U/ml and no lymph nodes metastases were 39.0 % versus only 5.1 % among patients with a CA 19.9 ≥ 50 who also had lymph node metastasis.

CONCLUSIONS

Examining an "all comer" cohort, <15 % of patients with PHCC or GBC could be considered cured after surgery. Factors such CA 19.9 level and lymph node metastasis independently predicted long-term outcome. Estimating the odds of statistical cure following surgery for biliary tract cancer can assist in decision-making as well as inform discussions around survivorship.

Prognostic Implications of Lymph Node Status for Patients With Gallbladder Cancer: A Multi-Institutional Study

BACKGROUND

Although the American Joint Committee on Cancer (AJCC) classification is the most accepted lymph node (LN) staging system for gallbladder adenocarcinoma (GBA), other LN prognostic schemes have been proposed. This study sought to define the performance of the AJCC LN staging system relative to the number of metastatic LNs (NMLN), the log odds of metastatic LN (LODDS), and the LN ratio (LNR).

METHODS

Patients who underwent curative-intent resection for GBA between 2000 and 2015 were identified from a multi-institutional database. The prognostic performance of various LN staging systems was compared by Harrell's C and the Akaike information criterion (AIC).

RESULTS

Altogether, 214 patients with a median age of 66.7 years (interquartile range [IQR] 56.5-73.1) were identified. A total of 1334 LNs were retrieved, with a median of 4 (IQR 2-8) LNs per patient. Patients with LN metastasis had an increased risk of death (hazard ratio [HR] 1.87; 95 % confidence interval [CI] 1.24-2.82; P = 0.003) and recurrence (HR 2.28; 95 % CI 1.37-3.80; P = 0.002). In the entire cohort, LNR, analyzed as either a continuous scale (C-index, 0.603; AIC, 803.5) or a discrete scale (C-index, 0.609; AIC, 802.2), provided better prognostic discrimination. Among the patients with four or more LNs examined, LODDS (C-index, 0.621; AIC, 363.8) had the best performance versus LNR (C-index, 0.615; AIC, 368.7), AJCC LN staging system (C-index, 0.601; AIC, 373.4), and NMLN (C-index, 0.613; AIC, 369.5).

CONCLUSIONS

Both LODDS and LNR performed better than the AJCC LN staging system. Among the patients who had four or more LNs examined, LODDS performed better than LNR. Both LODDS and LNR should be incorporated into the AJCC LN staging system for GBA.

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.