Prognostic factors in patients with gallbladder adenocarcinoma identified using competing-risks analysis: A study of cases in the SEER database

New trends in diagnosis and management of gallbladder carcinoma

Gallbladder (GB) carcinoma, although relatively rare, is the most common biliary tree cholangiocarcinoma with aggressiveness and poor prognosis. It is closely associated with cholelithiasis and long-standing large (> 3 cm) gallstones in up to 90% of cases. The other main predisposing factors for GB carcinoma include molecular factors such as mutated genes, GB wall calcification (porcelain) or mainly mucosal microcalcifications, and GB polyps ≥ 1 cm in size. Diagnosis is made by ultrasound, computed tomography (CT), and, more precisely, magnetic resonance imaging (MRI). Preoperative staging is of great importance in decision-making regarding therapeutic management. Preoperative staging is based on MRI findings, the leading technique for liver metastasis imaging, enhanced three-phase CT angiography, or magnetic resonance angiography for major vessel assessment. It is also necessary to use positron emission tomography (PET)-CT or 18F-FDG PET-MRI to more accurately detect metastases and any other occult deposits with active metabolic uptake. Staging laparoscopy may detect dissemination not otherwise found in 20%-28.6% of cases. Multimodality treatment is needed, including surgical resection, targeted therapy by biological agents according to molecular testing gene mapping, chemotherapy, radiation therapy, and immunotherapy. It is of great importance to understand the updated guidelines and current treatment options. The extent of surgical intervention depends on the disease stage, ranging from simple cholecystectomy (T1a) to extended resections and including extended cholecystectomy (T1b), with wide lymph node resection in every case or IV-V segmentectomy (T2), hepatic trisegmentectomy or major hepatectomy accompanied by hepaticojejunostomy Roux-Y, and adjacent organ resection if necessary (T3). Laparoscopic or robotic surgery shows fewer postoperative complications and equivalent oncological outcomes when compared to open surgery, but much attention must be paid to avoiding injuries. In addition to surgery, novel targeted treatment along with immunotherapy and recent improvements in radiotherapy and chemotherapy (neoadjuvant-adjuvant capecitabine, cisplatin, gemcitabine) have yielded promising results even in inoperable cases calling for palliation (T4). Thus, individualized treatment must be applied.

Metabolic parameters of pretreatment 2-[18F]fluoro-D-glucose positron emission tomography for prognosis in patients with gallbladder adenocarcinoma: a cohort study

Background

The incidence of gallbladder adenocarcinoma (GBA) is relatively low, yet it exhibits a high degree of malignancy and a significantly low 5-year survival rate. The aim of this study was to investigate the prognostic value of pretreatment 2-[18F]fluoro-D-glucose positron emission tomography {2-[18F]FDG PET} parameters in predicting outcomes for patients with GBA.

Methods

In total, 67 patients with GBA who underwent 2-[18F]FDG PET/computed tomography (CT) before treatment were retrospectively analyzed at Chinese PLA General Hospital from January 2012 to June 2022. All patients were diagnosed by pathology, and their baseline characteristics and clinical data were collected. The metabolic PET parameters of the primary and metastatic lesions were measured, including the maximum and average standardized uptake values (SUVs), metabolic tumor volume (MTV), and total lesion glycolysis (TLG). The prognostic significance of metabolic parameters and other clinical variables was assessed using Cox proportional hazards regression models. Differences in progression-free survival (PFS) and overall survival (OS) in relation to metabolic parameters were examined using the Kaplan-Meier method.

Results

During a median follow-up period of 14.2 months, 43 patients (64.2%) experienced tumor recurrence or progression, and 38 patients (56.7%) died of cancer. In the univariate Cox regression analysis, liver parenchymal invasion (P=0.001), lymph node metastasis (P=0.007), distant metastases (P=0.049), tumor differentiation (P=0.028), surgery (P=0.014), carcinoembryonic antigen (CEA) level (P=0.030), carbohydrate antigen 19-9 (CA19-9) level (P=0.003), TLG (P=0.005), MTV (P<0.001), sum of the TLGs of the primary and metastatic lesions (total TLG, tTLG) (P=0.001), and sum of the MTVs of the primary and metastatic lesions (total MTV, tMTV) (P<0.001) were significant predictors of PFS. In multivariate analysis, MTV was an independent predictor of PFS [hazard ratio (HR) =2.785; 95% confidence interval (CI): 1.204-6.441; P=0.017]. In the univariate Cox regression analysis, liver parenchymal invasion (P=0.001), lymph node metastasis (P=0.027), distant metastases (P=0.036), tumor differentiation (P=0.047), surgery (P=0.002), neutrophil-to-lymphocyte ratio (NLR) (P=0.011), CEA level (P=0.036), CA19-9 level (P<0.001), TLG (P=0.007), MTV (P<0.001), tTLG (P=0.003), and tMTV (P<0.001) were significant predictors of OS. In the multivariate analysis, higher CA19-9 levels >37 U/mL and a greater tMTV (HR =2.961; 95% CI: 1.092-8.024; P=0.033) were predictive of OS.

Conclusions

Our study results suggest that pretreatment 2-[18F]FDG PET parameters can not only assist in the diagnosis of patients with GBA but may also serve as predictive factors for the prognosis of these patients and should thus be applied in their treatment.

Prognostic Impact of Neoadjuvant Chemotherapy in Localized or Locoregionally Advanced Gallbladder Cancer: A Population-Based and Propensity Score Matched SEER Analysis

BACKGROUND

The effect of neoadjuvant chemotherapy (NACT) in gallbladder cancer (GBC) patients remains controversial. The aim of this study was to assess the impact of NACT on overall survival (OS) and cancer specific survival (CSS) in patients with localized or locoregionally advanced GBC, and to explore possible protective predictors for prognosis.

METHODS

Data for patients with localized or locoregionally advanced GBC (i.e., categories cTx-cT4, cN0-2, and cM0) from 2004 to 2020 were collected from the Surveillance, Epidemiology, and End Results (SEER) database. Patients in the NACT and non-NACT groups were propensity score matched (PSM) 1:3, and the Kaplan-Meier method and log-rank test were performed to analyze the impact of NACT on OS and CSS. Univariable and multivariable Cox regression models were applied to identify the possible prognostic factors. Subgroup analysis was conducted to identify patients who would benefit from NACT.

RESULTS

Of the 2676 cases included, 78 NACT and 234 non-NACT patients remained after PSM. In localized or locoregionally advanced GBC patients, the median OS of the NACT and non-NACT was 31 and 16 months (log-rank P < 0.01), and the median CSS of NACT and non-NACT was 32 and 17 months (log-rank P < 0.01), respectively. Longer median OS (31 vs 17 months, log-rank P < 0.01) and CSS (32 vs 20 months, log-rank P < 0.01) was associated with NACT compared with surgery alone. Multivariable Cox regression analysis showed that NACT, stage, and surgery type were prognostic factors for OS and CSS in GBC patients. Subgroup analysis revealed that the survival hazard ratios (HRs) of NACT vs non-NACT for localized or locoregionally advanced GBC patients were significant in most subgroups.

CONCLUSIONS

NACT may provide therapeutic benefits for localized or locoregionally advanced GBC patients, especially for those with advanced stage, node-positive, poorly differentiated or undifferentiated disease. NACT combined with radical surgery was associated with a survival advantage. Therefore, NACT combined with surgery may provide a better treatment option for resectable GBC patients.

Prognosis and Treatment Outcomes of Bone Metastasis in Gallbladder Adenocarcinoma: A SEER-Based Study

BACKGROUND

Gallbladder carcinoma (GBC) is a rare, aggressive malignancy comprising 0.5% of gastrointestinal cancers. It has poor survival outcomes due to its insidious onset, lack of standardized screening, and limited therapies. Advanced-stage diagnosis with liver, lymph node, and peritoneal metastasis is common, while bone metastasis is rare. The knowledge on bone metastasis in GBC is limited to case reports and small series, and its clinical significance is largely unexplored.

METHODS

The study extracted the demographic and clinical variables of patients with metastatic (M1) gallbladder adenocarcinoma from the Surveillance, Epidemiology, and End Results (SEER) database between 2011 and 2020. Descriptive statistics were used to analyze the demographic characteristics. The multivariate Cox regression analysis was used to calculate the hazard ratio. The overall survival (OS) was assessed using the Kaplan-Meier method, and the log-rank test was utilized to compare the survival between the groups.

RESULTS

A total of 2724 patients were included in the study. A total of 69% of the patients were female, and the median age was 68 (range 24-90+). A total of 7.4% of the patients had bone metastasis on diagnosis. The multivariate Cox analysis identified bone metastasis as an independent mortality risk factor in metastatic GBC (HR 1.50, p < 0.001). The patients were divided into two age groups: a younger age group (18-74 years) and an older age group (75+ years). In the younger group, the median OS with and without bone metastasis was 3 and 5 months, respectively (p < 0.0001). In the older age group, there was no significant difference in the OS between the patients with and without bone metastasis (p = 0.35). In the younger group who were treated with chemotherapy, the patients with bone metastasis had a significantly worse OS (median OS 5 months vs. 8 months, p < 0.0001). In the untreated group, the patients with bone metastasis in the younger age group had a significantly worse OS (median OS 1 month vs. 2 months, p = 0.014). In the patients with bone metastasis, those who did not receive chemotherapy had a significantly worse OS than those who were treated with chemotherapy in both age groups (younger age group: median OS 1 month vs. 5 months, p < 0.0001 and older age group: median OS 1 month vs. 5 months, p = 0.041).

CONCLUSIONS

Our findings suggest that the presence of bone metastasis in gallbladder adenocarcinoma is an independent prognostic factor associated with unfavorable survival outcomes in the younger age group (18-74 years). However, in the older age group (75+ years), the presence of bone metastasis did not impact the survival. Treatment with chemotherapy was associated with extended survival in all patients. Thus, early detection and aggressive management of bone metastasis, including the consideration of chemotherapy, may be crucial in improving the OS and quality of life for individuals with gallbladder adenocarcinoma.

Incidence and risk factors of cardiovascular mortality in patients with gastrointestinal adenocarcinoma

BACKGROUND

Gastrointestinal (GI) cancers are common and fatal. Improved cancer-directed therapies, with thier substantial role in improving cancer-specific survival, may increase non-cancer mortality-including cardiovascular mortality-in these patients.

AIM

To identify the risk factors of cardiovascular mortality in GI adenocarcinoma patients.

METHODS

Data of GI adenocarcinoma patients were gathered from the Surveillance, Epidemiology, and End Results database. We used Pearson's chi-square test to assess the relationships between categorical variables. We used the Kaplan-Meyer test in the univariate analysis and Cox regression test for the multivariate analysis.

RESULTS

Among 556,350 included patients, 275,118 (49.6%) died due to adenocarcinoma, 64,079 (11.5%) died due to cardiovascular causes, and 83,161 (14.9%) died due to other causes. Higher rates of cardiovascular mortality were found in patients ≥ 50 years (HR, 8.476; 95% CI, 7.91-9.083), separated (HR, 1.27; 95% CI, 1.184-1.361) and widowed (HR, 1.867; 95% CI, 1.812-1.924), patients with gastric (HR, 1.18; 95% CI, 1.1-1.265) or colorectal AC (HR, 1.123; 95% CI, 1.053-1.198), and patients not undergone surgery (HR, 2.04; 95% CI, 1.958-2.126). Lower risk patients include females (HR, 0.729; 95% CI, 0.717-0.742), blacks (HR, 0.95; 95% CI, 0.924-0.978), married (HR, 0.77; 95% CI, 0.749-0.792), divorced (HR, 0.841; 95% CI, 0.807-0.877), patients with pancreatic AC (HR, 0.83; 95% CI, 0.757-0.91), and patients treated with chemotherapy (HR, 0.416; 95% CI, 0.406-0.427).

CONCLUSIONS

Risk factors for cardiovascular mortality in GI adenocarcinoma include advanced age, males, whites, separated and widowed, gastric or colorectal adenocarcinoma, advanced grade or advanced stage of the disease, no chemotherapy, and no surgery. Married and divorced, and patients with pancreatic adenocarcinoma have a lower risk.

Development and validation of prognostic nomograms in patients with gallbladder mucinous adenocarcinoma: A population-based study

Background

Gallbladder mucinous adenocarcinoma (GBMAC) is an uncommon malignant gallbladder tumor. There are few studies on its prognosis, with the majority consisting of small series or individual cases. We sought to develop and validate nomograms for predicting overall survival (OS) and cancer-specific survival (CSS) in GBMAC patients.

Methods

The clinicopathological data of GBMAC patients from 1975 to 2019 was extracted from the Surveillance, Epidemiology, and End Results (SEER) database, and all patients were randomly divided into a training cohort (70%) and a validation cohort (30%). Using multivariate Cox regression analyses based on Akaike information criterion (AIC), prognostic and important variables for GBMAC were determined. On the basis of these factors, nomograms were developed to predict the 1-, 3-, and 5-year OS and CSS rates of patients with GBMAC. Multiple parameters, including the area under the subject operating characteristic curve (AUC), the calibration plots, and the decision curve analysis (DCA), were then used to evaluate the accuracy of nomograms.

Results

Following exclusion, a total of 707 GBMAC patients were enrolled, and the training cohort (490, 70%) and validation cohort (217, 30%) were randomly assigned. Grade, surgery, radiation, and SEER stage were predictive factors for patients with GBMAC, as indicated by univariate and multivariate Cox regression analyses based on AIC. We created nomograms for predicting OS and CSS in GBMAC using the four factors. The calibration curves and area under the curves (AUCs) indicated that our nomograms have a moderate degree of predictive accuracy and capability. The results of the DCA revealed that the nomogram has a high predictive value.

Conclusion

We established the first nomograms for predicting 1-, 3-, and 5-year OS and CSS in GBMAC patients, thereby contributing to the prognostication of patients and clinical management.

High-Quality Surgery for Gallbladder Carcinoma: Rare, Associated with Disparity, and Not Substitutable by Chemotherapy

BACKGROUND

Oncologic surgery for T1b-T3 gallbladder carcinoma (GBC) consists of gallbladder fossa resection or bisegmentectomy IVb/V with negative margins and portal/retropancreatic lymphadenectomy. Frequency of high quality oncologic surgery, factors associated with its use, and the ability of chemotherapy to rescue low-quality surgery (LQS) remain unknown.

METHODS

The NCDB was queried for patients diagnosed with stage I-III (T1b-T3) GBC undergoing curative-intent surgery from 2004 to 2016. These patients were divided into two groups based on receiving high quality surgery (HQS) or not; HQS was defined as cholecystectomy with partial hepatectomy, lymph node harvest ≥ 6, and negative margins. Logistic regression and Kaplan-Meier survival analyses were performed.

RESULTS

A total of 3796 patients met inclusion criteria; only 364 (9.6%) met HQS criteria, and 3432 (90.4%) did not achieve HQS and were deemed low-quality surgery (LQS). HQS was associated with improved median overall survival (55.1 vs. 25.5 months, P < .001). Adjuvant chemotherapy (AC) was not able to rescue LQS with poorer survival compared to HQS without AC (27.9 vs 55.1 months, P < .001). Factors associated with HQS included private insurance (OR 1.809, P < .001), higher income (OR 1.380, P = .038), urban/rural residence (vs metropolitan) (OR 1.641, P = .001), higher education (OR 1.342, P = .031), Medicaid expansion states (OR 1.405, P = .005), stage 3 GBC (OR 1.642, P = .020), and reresection (OR 2.685, P < .001). Factors associated with LQS included older age (OR 0.974, P < .001), comorbidities (OR 0.701, P = .004), and laparoscopic approach (0.579, P < .001). Facility type incrementally improved HQS rate (integrated cancer network vs. comprehensive community, 9.8% vs. 6.1%, OR 1.694, P = .003; academic/research center vs. integrated cancer network, 14.9% vs. 9.8%, OR 1.599, P = .003).

CONCLUSION

While HQS for GBC strongly improves survival, it is infrequently practiced. The newly identified factors that improve survival for GBC, such as centralization, open approach, and insurance coverage, are modifiable and, therefore, should be considered to achieve optimal outcomes.

Development and external validation of a novel nomogram for predicting cancer-specific survival in patients with ascending colon adenocarcinoma after surgery: a population-based study

Background

This study aimed to develop and validate a novel nomogram to predict the cancer-specific survival (CSS) of patients with ascending colon adenocarcinoma after surgery.

Methods

Patients with ascending colon adenocarcinoma were enrolled from the Surveillance, Epidemiology, and End Results (SEER) database from 1973 to 2015 and randomly divided into a training set (5930) and a validation set (2540). The cut-off values for age, tumour size and lymph node ratio (LNR) were calculated via X-tile software. In the training set, independent prognostic factors were identified using univariate and multivariate Cox analyses, and a nomogram incorporating these factors was subsequently built. Data from the validation set were used to assess the reliability and accuracy of the nomogram and then compared with the 8th edition of the American Joint Committee on Cancer (AJCC) tumour-node-metastasis (TNM) staging system. Furthermore, external validation was performed from a single institution in China.

Results

A total of 8470 patients were enrolled from the SEER database, 5930 patients were allocated to the training set, 2540 were allocated to the internal validation set and a separate set of 473 patients was allocated to the external validation set. The optimal cut-off values of age, tumour size and lymph node ratio were 73 and 85, 33 and 75 and 4.9 and 32.8, respectively. Univariate and multivariate Cox multivariate regression revealed that age, AJCC 8th edition T, N and M stage, carcinoembryonic antigen (CEA), tumour differentiation, chemotherapy, perineural invasion and LNR were independent risk factors for patient CSS. The nomogram showed good predictive ability, as indicated by discriminative ability and calibration, with C statistics of 0.835 (95% CI, 0.823–0.847) and 0.848 (95% CI, 0.830–0.866) in the training and validation sets and 0.732 (95% CI, 0.664–0.799) in the external validation set. The nomogram showed favourable discrimination and calibration abilities and performed better than the AJCC TNM staging system.

Conclusions

A novel validated nomogram could effectively predict patients with ascending colon adenocarcinoma after surgery, and this predictive power may guide clinicians in accurate prognostic judgement.

Clinical efficacy of adjuvant treatments for patients with resected biliary tract cancer: a systematic review and network meta-analysis

OBJECTIVE

This study aimed to determine the benefits of adjuvant therapy in patients with resected biliary tract cancer (BTC) and identify the optimal adjuvant treatment scheme.

DESIGN

Systematic review and network meta-analysis.

DATA SOURCES

Studies comparing different adjuvant therapies in patients with BTC were searched in PubMed, Embase, CINAHL, Cochrane Central Register of Controlled Trials and ClinicalTrials.gov databases from inception to December 2021. Additionally, the references were manually searched for the related literature.

MATERIALS AND METHODS

Eligible studies were identified, and data were extracted independently by two authors. A random-effects network meta-analysis was performed using R software. The pooled outcomes of overall survival (OS) and disease-free survival (DFS) were measured using the combined HRs with 95% CIs.

RESULTS

Nineteen eligible studies reporting three types of adjuvant therapies were included in our network meta-analysis. Adjuvant radiotherapy (ART, HR 0.62; 95% CI 0.42 to 0.93), adjuvant chemoradiotherapy (ACRT; HR 0.71; 95% CI 0.54 to 0.83) and adjuvant chemotherapy (ACT; HR 0.84; 95% CI 0.68 to 0.98) were more effective in prolonging OS than that of observation, with no significant difference between the three adjuvant therapies. Moreover, the improvement in DFS was also found in ACRT and ACT compared with that of observation (HR 0.60; 95% CI 0.45 to 0.75; HR 0.82; 95% CI 0.68 to 0.97, respectively). Furthermore, ACRT obtained a slightly better DFS benefit compared with that of ACT (HR 0.73; 95% CI 0.53 to 0.95).

CONCLUSIONS

Our primary results demonstrated that, compared with that of observation, ACRT and ACT after radical resection could provide better OS and DFS benefits in patients with BTC. However, ART only showed improvement in OS, but not in DFS. Due to the lack of head-to-head studies of ACT, ACRT and ART, the above results need to be further verified by prospective randomised controlled trials.

Evolving Paradigms in the Systemic Treatment of Advanced Gallbladder Cancer: Updates in Year 2022

Gallbladder cancer (GBC) is a biological, anatomical, and clinically distinct subset of biliary tract cancers (BTC), which also include extra- and intra-hepatic cholangiocarcinoma. The advent of next-generation sequencing (NGS) clearly shows that GBC is genetically different from cholangiocarcinoma. Although GBC is a relatively rare cancer, it is highly aggressive and carries a grave prognosis. To date, complete surgical resection remains the only path for cure but is limited to patients with early-stage disease. The majority of the patients are diagnosed at an advanced, inoperable stage when systemic treatment is administered as an attempt to enable surgery or for palliation. Gemcitabine and platinum-based chemotherapies have been the main treatment modality for unresectable, locally advanced, and metastatic gallbladder cancer. However, over the past decade, the treatment paradigm has evolved. These include the introduction of newer chemotherapeutic strategies after progression on frontline chemotherapy, incorporation of targeted therapeutics towards driver mutations of genes including HER2, FGFR, BRAF, as well as approaches to unleash host anti-tumor immunity using immune checkpoint inhibitors. Notably, due to the rarity of BTC in general, most clinical trials included both GBC and cholangiocarcinomas. Here, we provide a review on the pathogenesis of GBC, past and current systemic treatment options focusing specifically on GBC, clinical trials tailored towards its genetic mutations, and emerging treatment strategies based on promising recent clinical studies.

Neuroendocrine neoplasms of the gallbladder: early detection and surgery is key to improved outcome

PURPOSE

Neuroendocrine neoplasms (NENs) of the gallbladder are very rare. As a result, the classification of pathologic specimens from gallbladder NENs, currently classified as gallbladder neuroendocrine tumors (GB-NETs) and carcinomas (GB-NECs), is inconsistent and makes nomenclature, classification, and management difficult. Our study aims to evaluate the epidemiological trend, tumor biology, and outcomes of GB-NET and GB-NEC over the last 5 decades.

METHODS

This is a retrospective analysis of the SEER database from 1973 to 2016. The epidemiological trend was analyzed using the age-adjusted Joinpoint regression analysis. Survival was assessed with Kaplan-Meier analysis and Cox regression was used to assess predictors of poor survival.

RESULTS

A total of 482 patients with GB-NEN were identified. Mean age at diagnosis was 65.2 ± 14.3 years. Females outnumbered males (65.6% vs. 34.4%). The Joinpoint nationwide trend analysis showed a 7% increase per year from 1973 to 2016. The mean survival time after diagnosis of GB-NEN was 37.11 ± 55.3 months. The most common pattern of nodal distribution was N0 (50.2%) followed by N1 (30.9%) and N2 (19.2%). Advanced tumor spread (into the liver, regional, and distant metastasis) was seen in 60.3% of patients. Patients who underwent surgery had a significant survival advantage (111.0 ± 8.3 vs. 8.3 ± 1.2 months, p < 0.01). Cox regression analysis showed advanced age (p < 0.01), tumor stage (P < 0.01), tumor extension (p < 0.01), and histopathologic grade (p < 0.01) were associated with higher mortality.

CONCLUSION

Gallbladder NENs are a rare histopathological variant of gallbladder cancer that is showing a rising incidence in the USA. In addition to tumor staging, surgical resection significantly impacts patient survival, when patients are able to undergo surgery irrespective of tumor staging. Advanced age, tumor extension, and histopathological grade of the tumor were associated with higher mortality.

Prognostic Nomograms to Predict Survival of Patients with Resectable Gallbladder Cancer: A Surveillance, Epidemiology, and End Results (SEER)-Based Analysis

Background

Gallbladder adenocarcinoma (GBAC) is globally acknowledged as one of the most common malignancies among all gastrointestinal cancers. Despite prognosis of GBAC patients remains poor, patients with early-stage disease can be observed with long-term survival.

Material/Methods

In this study, 2556 patients with pathological GBAC between 2010 and 2015 were derived from the Surveillance, Epidemiology, and End Results (SEER) database. The prognostic nomograms containing all independent prognostic factors for predicting overall survival (OS) and cancer-specific survival (CSS) were constructed to achieve superior prognostic discriminatory ability.

Results

Based on the AJCC 7^th TNM staging system, we found the TNM substaging was not accurate enough to predict the survival and stratify the risk. Based on the results of univariate and multivariate analyses, a more precise prognostic nomogram was constructed containing all significant independent prognostic factors (age, grade, TNM stage, bone metastasis, and chemotherapy) for OS, while age, grade, TNM stage, bone metastasis and radiotherapy significant independent prognostic factors for CSS. The C-index of the constructed nomogram for predicting OS and CSS was 0.740 and 0.737 higher than that of TNM staging alone (0.667 for OS and 0.689 for CSS), respectively. In addition, the calibration curves and decision curve analysis further showed its robust power in survival prediction.

Conclusions

The constructed nomograms showed better discrimination abilities to predict OS and CSS rates at 1, 3, and 5 years. In the future, these constructed models for this disease will assist in risk stratification to guide GBAC treatment.

Validation of the 8th Edition American Joint Commission on Cancer (AJCC) Gallbladder Cancer Staging System: Prognostic Discrimination and Identification of Key Predictive Factors

The scope of our study was to compare the predictive ability of American Joint Committee on Cancer (AJCC) 7th and 8th edition in gallbladder carcinoma (GBC) patients, investigate the effect of AJCC 8th nodal status on the survival, and identify risk factors associated with the survival after N reclassification using the National Cancer Database (NCDB) in the period 2005-2015. The cohort consisted of 7743 patients diagnosed with GBC; 202 patients met the criteria for reclassification and were denoted as stage ≥III by AJCC 7th and 8th edition criteria. Overall survival concordance indices were similar for patients when classified by AJCC 8th (OS c-index: 0.665) versus AJCC 7th edition (OS c-index: 0.663). Relative mortality was higher within strata of T1, T2, and T3 patients with N2 compared with N1 stage (T1 HR: 2.258, p < 0.001; T2 HR: 1.607, p < 0.001; Τ3 HR: 1.306, p < 0.001). The risk of death was higher in T1-T3 patients with Nx compared with N1 stage (T1 HR: 1.281, p = 0.043, T2 HR: 2.221, p < 0.001, T3 HR: 2.194, p < 0.001). In patients with AJCC 8th edition stage ≥IIIB GBC and an available grade, univariate analysis showed that higher stage, Charlson-Deyo score ≥ 2, higher tumor grade, and unknown nodal status were associated with an increased risk of death, while year of diagnosis after 2013, academic center, chemotherapy. and radiation therapy were associated with decreased risk of death. Chemotherapy and radiation therapy were associated with decreased risk of death in patients with T3-T4 and T2-T4 GBC, respectively. In conclusion, the updated AJCC 8th GBC staging system was comparable to the 7th edition, with the recently implemented changes in N classification assessment failing to improve the prognostic performance of the staging system. Further prospective studies are needed to validate the T2 stage subclassification as well as to clarify the association, if any is actually present, between advanced N staging and increased risk of death in patients of the same T stage.