Lymphatic spread of T2 gallbladder carcinoma: Regional lymphadenectomy is required independent of tumor location

[Preliminary results of fluorescent lymphography in patients with biliary cancer undergoing liver resection]

OBJECTIVE

To evaluate the diagnostic capability of intraoperative fluorescence lymphography (FLG) in detecting of sentinel lymph nodes (SLN) and lymph outflow pathways in patients with biliary cancer (BC).

MATERIAL AND METHODS

From April 2023 till March 2024, ten liver resections for BC were performed using FLG. We carried out the standard lymph node dissection with additional removal of lymph nodes (LN) that have accumulated indocyanine green (ICG). The lymphatic outflow pathways in all patients and frequency of SLN invasion were evaluated.

RESULTS

Ten patients were included: five patients had been diagnosed with intrahepatic cholangiocarcinoma (IHCC), two - with perichilar tumor (PT), the last three ones had gallbladder cancer (GBC). SLN No. 1 were detected in eight patients, the accumulation of ICG was detected in the following groups of LN: No. 8 (n=2), No. 13 (n=1), No. 12b (n=2), cystic lymph node (n=2), and No. 7 (n=1). SLN No. 2 was detected in seven patients. In three cases LN No. 13 were stained, in one - LN No. 12a, in another - LN No. 8. In two patients, staining of vesicular LN was noted. The combined morphological assessment of SLN No. 1 and SLN No. 2 made it possible to predict the presence of LN metastases in all patients (100%, n=3). Fluorescence of third-order LN was detected in four patients. In one case, the staining of LN No. 13 was noted. Another patient revealed accumulation of ICG in LN No. 3. In two cases, at the third stage, fluorescence of LN No. 7 was noted, while metastatic invasion of LN No. 7 was detected in one patient with IHCC.

CONCLUSION

Using FLG, it was possible to determine an alternative lymph flow outpath to LN No. 7 in three patients. The method allowed to identify and remove metastatic LN No. 7 in one case. 100% sensitivity was shown in the determination of SLN in BC in a small group of patients. It is advisable to study the sensitivity of the method in large-scale studies.

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.

Controversies and future directions in the management of gallbladder cancer

Gallbladder cancer (GBC) is a rare malignancy worldwide, with 140,000 new patients each year and more than 100,000 deaths annually. The review aims to address the controversial aspects of managing GBC. Regional differences of the study worldwide remain pending, and comparative mutational profiles will provide more information on the pathogenesis of GBC. However, certain pathologic aspects are discussed, such as the staging of early GBC, outcome differences between T2 pathologically staged patients, and the necessity of a uniform pathologic report. The surgical management of GBC is still under debate. The extent of liver resection, type of lymphadenectomy, and selection of patients for extended resection are aspects of the disease that require revision. Laparoscopic and robotic approaches were initially slow to develop. However, with time, they have demonstrated their value in the surgical management of GBC. The OMEGA survey, performed to analyze the management practice of surgical treatment of GBC worldwide, demonstrated differences from the recommended guidelines. The OMEGA study, the largest cohort study, examined the outcomes of surgical intervention in 3676 patients from 133 centers. Regarding future directions, the value of collaborative efforts between centers and regions must be emphasized to better understand the different aspects of the disease and globally improve therapeutic strategies for GBC.

Gallbladder cancer: current and future treatment options

Surgery remains the preferred treatment option for early-stage gallbladder cancer (GBC). According to the anatomical position of the primary tumor, accurate preoperative stage and strict control of surgical indications, appropriate surgical strategies are selected to achieve the optimal surgical effect. However, most patients have already been at the locally advanced stage or the tumor has metastasized at the initial diagnosis. The postoperative recurrence rate and 5-year survival rate remain unsatisfactory even after radical resection for gallbladder cancer. Hence, there is an urgent need for more treatment options, such as neoadjuvant therapy, postoperative adjuvant therapy and first-line and second-line treatments of local progression and metastasis, in the whole-course treatment management of gallbladder cancer patients. In recent years, the application of molecular targeted drugs and immunotherapy has brought greater hope and broader prospects for the treatment of gallbladder cancer, but their effects in improving the prognosis of patients still lack sufficient evidence-based medicine evidence, so many problems should be addressed by further research. Based on the latest progress in gallbladder cancer research, this review systematically analyzes the treatment trends of gallbladder cancer.

Subserosal vascular density predicts oncological features of T2 gallbladder cancer

PURPOSE

Tumor sidedness (hepatic side vs. peritoneal side) reportedly predicts microvascular invasion and survival outcomes of T2 gallbladder cancer, although the actual histopathological mechanism is not fully understood.

METHODS

The clinical relevance of tumor sidedness was revisited in 84 patients with gallbladder cancer using histopathological analysis of the vascular density of the gallbladder wall.

RESULTS

Hepatic-side tumor location was associated with overall survival (OS) (hazard ratio [HR], 13.62; 95% confidence interval [CI], 2.09-88.93) and recurrence-free survival (RFS) (HR, 8.70; 95% CI, 1.36-55.69) in T2 tumors. The Adjusted Kaplan-Meier curve indicated a clear survival difference between T2a (peritoneal side) and T2b (hepatic side) tumors (P = 0.006). A review of 56 pathological specimens with gallbladder cancer and 20 control specimens demonstrated that subserosal vascular density was significantly higher on the hepatic side of the gallbladder, regardless of the presence of cancer (P < 0.001). Multivariate analysis also confirmed that higher subserosal vascular density was significantly associated with poor OS (HR, 1.73; 95% CI, 1.10-2.73 per 10 microscopic fields) and poor RFS (HR, 1.62; 95% CI, 1.06-2.49) in T2  gallbladder cancer.

CONCLUSION

Higher subserosal vascular density may account for the higher incidence of cancer spread and the poor prognosis of T2b gallbladder cancer.

Gallbladder Cancer: Current Multimodality Treatment Concepts and Future Directions

Gallbladder cancer (GBC) is the most common primary tumor site of biliary tract cancer (BTC), accounting for 0.6% of newly diagnosed cancers and 0.9% of cancer-related deaths. Risk factors, including female sex, age, ethnic background, and chronic inflammation of the gallbladder, have been identified. Surgery is the only curative option for early-stage GBC, but only 10% of patients are primary eligible for curative treatment. After neoadjuvant treatment, up to one-third of locally advanced GBC patients could benefit from secondary surgical treatment. After surgery, only a high-risk subset of patients benefits from adjuvant treatment. For advanced-stage GBC, palliative chemotherapy with gemcitabine and cisplatin is the current standard of care in line with other BTCs. After the failure of gemcitabine and cisplatin, data for second-line treatment in non-resectable GBC is poor, and the only recommended chemotherapy regimen is FOLFOX (5-FU/folinic acid and oxaliplatin). Recent advances with the PD-L1 inhibitor durvalumab open the therapy landscape for immune checkpoint inhibition in GBC. Meanwhile, targeted therapy approaches are a cornerstone of GBC therapy based on molecular profiling and new evidence of molecular differences between different BTC forms and might further improve the prognosis of GBC patients.

Systematic review and meta-analysis of survival outcomes in T2a and T2b gallbladder cancers

BACKGROUND

The 8th edition of AJCC TNM staging of Gallbladder cancer subdivided T2 stage into T2a and T2b based on tumour location. This meta-analysis aimed to investigate the long-term outcomes in T2a and T2b gallbladder cancers.

METHODS

Literature search of Medline, Web of science, Embase and Cochrane databases was performed. Study characteristics, survival and recurrence data were extracted for meta-analysis of effect estimates and of individual patient data.

RESULTS

Fifteen retrospective studies (2531 patients, T2a = 1332, T2b = 199) were included in the meta-analysis. Overall survival (OS) was significantly worse in patients with T2b compared to T2a tumours (HR 2.18, 95% CI 1.67-2.86, p < 0.0001). Meta-analysis of individual patient data (n = 629) showed similar results (HR 1.92, 95% CI 1.43-2.58, p < 0.00001). Patients with T2b tumours had higher risk of recurrence compared to T2a (OR 3.19, 95% CI 1.40-7.28, p = 0.006) and were more likely to receive adjuvant chemotherapy (OR 1.76, 95% CI 1.12-2.84, p = 0.014). Liver resection improved OS in T2b tumours (HR 2.99, CI 1.73-5.16, p < 0.0001).

CONCLUSION

T2b gallbladder tumours have worse overall survival and increase risk of recurrence compared to T2a. Liver resection appears to improve OS in patients with T2b tumours. However, high quality multicenter data is required to confirm these results.

Comparing survival rate and appropriate surgery methods according to tumor location in T2 gallbladder cancer

BACKGROUND

The survival outcomes and optimal extent of surgery of T2 gallbladder cancers remain controversial. We aimed to investigate the difference in overall/disease-free survival rates and assess the prognosis of T2 gallbladder cancers.

METHODS

We retrospectively reviewed electronic medical records of 147 patients who underwent surgical resection for pathologically confirmed T2 gallbladder cancer between January 2003 and December 2012. Patients were categorized into two groups according to the tumor location (T2a vs. T2b) and three groups according to surgery method (simple cholecystectomy, cholecystectomy with lymph node dissection, and extended cholecystectomy). We compared the overall and disease-free survival rates according to T2 subgroups and surgery methods. Cox proportional hazard analysis was performed to evaluate prognostic factors for the overall survival of T2 gallbladder cancer.

RESULTS

Of all patients, 40 (27.2%) and 107 (72.8%) were diagnosed with T2a and T2b gallbladder cancers, respectively. The 5-year overall and disease-free survival rates were 75.0% vs. 73.8% (p = 0.653) and 72.5% vs. 70.1% (p = 0.479) in T2a and T2b gallbladder cancers, respectively. There was no difference in the survival rate among T2a gallbladder cancer according to the surgery method. However, in T2b gallbladder cancer, extended cholecystectomy showed a better overall survival than simple cholecystectomy and cholecystectomy with lymph node dissection groups (p = 0.043 and p = 0.003, respectively).

CONCLUSIONS

There is no difference in overall and disease-free survival rates according to the location of T2 gallbladder cancers. Extended cholecystectomy increases overall survival rate, especially in T2b gallbladder cancers.

Laparoscopic surgery for oncologic extended resection of T1b and T2 incidental gallbladder carcinoma at a high-volume center: a single-center experience in China

BACKGROUND

Surgical treatment is still the most effective treatment for gallbladder cancer. For the patients with stage T1b and above, the current guidelines recommend the extended radical operation, and oncologic extended resection can benefit the survival of the patients. The laparoscopic approach is still in the early phase, and its safety and oncological outcomes are not well known.

OBJECTIVE

To evaluate the technical feasibility and oncological outcomes of laparoscopic surgery for oncologic extended resection of early-stage incidental gallbladder carcinoma.

RESULTS

This study included 18 male and 32 female patients. Twenty patients underwent laparoscopic oncologic extended resection and 30 patients underwent open oncologic extended resection. All of the patients had R0 resection. A laparoscopic approach was associated with less intraoperative blood loss (242 ± 108.5 vs 401 ± 130.3; p < 0.01) and shorter duration of postoperative hospital stay (6.2 ± 2.4 vs 8.6 ± 2.3; p < 0.01). There was no statistically significant difference between two groups for lymph nodes yield (5.4 ± 3.5 vs 5.8 ± 2.1; p > 0.05), incidence of lymphatic metastasis (15% vs 16.67%; p > 0.05), residual disease (20% vs 23.3%; p > 0.05), and postoperative morbidity (15% vs 20%; p > 0.05). During follow-up time of median 20.95 (12-29.5) months, no significant difference was found between the two groups for early tumor recurrence (10% vs 13.33%; p > 0.05) and disease-free survival (p > 0.05).

CONCLUSION

Laparoscopic surgery may offer similar intraoperative, perioperative, and short-term oncological outcomes as an open oncologic extended resection for incidental gallbladder carcinoma.

Tumor location and concurrent liver resection, impact survival in T2 gallbladder cancer: a meta-analysis of the literature

Aim of doing this review was to give a uniform consensus on prognostic impact of tumor location (hepatic vs peritoneal), liver resection and adjuvant chemotherapy in gall bladder cancer and, to compare them with previous well-studied factors of survival. We systematically review PubMed, Scopus and Cochrane for relevant articles with no date restrictions, language was restricted to English. Those articles were included that had provided Hazard ratio (HR) of survival for T2 gall bladder cancer. We identified nine retrospective studies published between 2014 and 2020 with 2345 patients. Meta-analysis showed that T2b (hepatic) cancers had higher odds of mortality (HR 3.16 [2.11, 4.74], I2 = 0%). Liver resection was associated with significantly higher odds of 5-year overall survival only in T2b (2.20 [1.33, 3.63], I2 = 67%), adjuvant chemotherapy was not associated with any significant decrease in mortality risk (0.98 [0.83-1.16]. I2 = 20%). Hepatic sided gall bladder tumors carry higher odds for mortality and recurrence. T2a tumors can be managed without hepatic resection. To risk stratify patients we also formulated a scoring system for mortality risk.

Anatomic location of residual disease after initial cholecystectomy independently determines outcomes after re-resection for incidental gallbladder cancer

PURPOSE

This study aimed to elucidate the impact of anatomic location of residual disease (RD) after initial cholecystectomy on survival following re-resection of incidental gallbladder cancer (IGBC).

METHODS

Patients with pT2 or pT3 gallbladder cancer (36 with IGBC and 171 with non-IGBC) who underwent resection were analyzed. Patients with IGBC were classified as follows according to the anatomic location of RD after initial cholecystectomy: no RD (group 1); RD in the gallbladder bed, stump of the cystic duct, and/or regional lymph nodes (group 2); and RD in the extrahepatic bile duct and/or distant sites (group 3).

RESULTS

Timing of resection (IGBC vs. non-IGBC) did not affect survival in either multivariate or propensity score matching analysis. RD was found in 16 (44.4%) of the 36 patients with IGBC; R0 resection following re-resection was achieved in 32 patients (88.9%). Overall survival (OS) following re-resection was worse in group 3 (n = 7; 5-year OS, 14.3%) than in group 2 (n = 9; 5-year OS, 55.6%) (p = 0.035) or in group 1 (n = 20; 5-year OS, 88.7%) (p < 0.001). There was no survival difference between groups 1 and 2 (p = 0.256). Anatomic location of RD was independently associated with OS (group 2, HR 2.425, p = 0.223; group 3, HR 9.627, p = 0.024).

CONCLUSION

The anatomic location of RD independently predicts survival following re-resection, which is effective for locoregional disease control in IGBC, similar to resection for non-IGBC. Not all patients with RD have poor survival following re-resection for IGBC.

Prognostic Significance of Tumor Location in T2 Gallbladder Cancer: A Systematic Review and Meta-Analysis

(1) Background: The AJCC Cancer Staging Manual, Eighth Edition, subdivided T2 GBC into T2a and T2b. However, there still exist a lack of evidence on the prognostic significance of tumor location. The aim of the present study was to examine the existing evidence to determine the prognostic significance of tumor location of T2 gallbladder cancer (GBC) and to evaluate the optimal surgical extent according to tumor location. (2) Methods: We searched for relevant literature published in the electronic databases PubMed, MEDLINE, Web of Science, Cochrane Library, and Embase before September 2020 using search terms related to gallbladder, cancer, and stage. Data were weighted and pooled using random-effects modeling. (3) Results: Seven studies were deemed eligible for inclusion, representing a cohort of 1789 cases of resected T2 GBC. The overall survival for T2b tumor was significantly worse than that for T2a tumor (HR, 2.141; 95% confidence interval (CI), 1.140 to 4.023; I² = 71.4%; P_chⁱ² = 0.007). The rate of lymph node metastasis was lower in the T2a group (26.6%) than in the T2b group (36.6%) (OR, 2.164; 95% CI, 1.309 to 3.575). There was no evidence of a survival difference between the patients who underwent extended cholecystectomy and simple cholecystectomy in T2a GBC (OR, 0.802; 95% CI, 0.618 to 1.042) and T2b GBC (OR, 0.820; 95% CI, 0.620 to 1.083). (4) Conclusions: Hepatic side tumor was a significant poor prognostic factor in T2 GBC. Extended cholecystectomy and simple cholecystectomy showed comparable survival outcomes in T2 GBC, and additional large-scale prospective studies are warranted to establish evidence-based treatment guidelines for T2 GBC.

Essential updates 2019/2020: Surgical treatment of gallbladder cancer

Gallbladder cancer is a biliary tract cancer that originates in the gallbladder and cystic ducts and is recognized worldwide as a refractory cancer with early involvement of the surrounding area because of its anatomical characteristics. Although the number of cases is increasing steadily worldwide, the frequency of this disease remains low, making it difficult to plan large-scale clinical studies, and there is still much discussion about the indications for surgical resection and the introduction of multidisciplinary treatment. Articles published between 2019 and 2020 were reviewed, focusing mainly on the indications for surgical resection for each tumor stage, the treatment of incidental gallbladder cancer, and current trends in minimally invasive surgery for gallbladder cancer.

Rates, Predictors, and Outcomes of Portal Lymphadenectomy for Resectable Gallbladder Cancer

INTRODUCTION

Lymphadenectomy (LND) is recommended following surgical resection of ≥ T1b gallbladder cancer (GBC). However, frequency and stage-specific survival benefits of LND remain unclear.

PATIENTS AND METHODS

The National Cancer Database (NCDB; 2006-15) was queried for resected pathologic stage I-III GBC. LND performance, predictors of receiving LND, and LND association with overall survival (OS) were assessed.

RESULTS

Of 2302 total patients, 1343 (58.3%) underwent LND. Patients who underwent LND were younger and more frequently had private health insurance, a negative surgical margin, higher pathologic T stage, and received adjuvant chemotherapy (all p < 0.001). LND rates were highest at academic centers (70.1%) relative to all other facility types (p < 0.001). LND was independently associated with improved OS [hazard ratio (HR) 0.52, 95% confidence interval (CI) 0.44-0.61]. LND was associated with improved OS for pT1b, pT2, and pT3 patients (all p < 0.05) on univariate analysis. LND was independently associated with improved OS in pT2 (HR 0.44, CI 0.35-0.56) and pT3 (HR 0.54, CI 0.43-0.69) patients.

CONCLUSIONS

LND is associated with a 48% reduction in risk of death in patients with resectable non-metastatic GBC, with greatest impact in pT2-3 patients. Patients without LND have similar OS to patients with node-positive disease, highlighting the importance of LND. Underutilization of LND likely results in undertreatment of patients with undiagnosed nodal disease, which may contribute to unfavorable oncologic outcomes.

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.

Prognostic Significance of Tumor Location in T2 Gallbladder Cancer: A Korea Tumor Registry System Biliary Pancreas (KOTUS-BP) Database Analysis

Background: T2 gallbladder cancer (GBC) is subdivided into T2a and T2b by the American Joint Committee on Cancer (AJCC) 8th edition. However; there is a lack of evidence for the prognostic significance of tumor location and validation with large-scale studies is needed. The aims of this study were to investigate the clinical features and clinical outcomes of T2 GBC according to tumor location and determine the prognostic significance of tumor location and an appropriate surgical strategy. Methods: Between 2000 and 2014 the Korea Tumor Registry System Biliary Pancreas (KOTUS-BP) database was used to identify and enroll a total 707 patients with pathologically diagnosed T2 GBC who underwent curative resection. Clinicopathological findings and long-term follow-up results were analyzed. Results: The incidence of lymph node metastasis in T2b was significantly higher than that of T2a tumors (37.9% vs. 29.5%, p = 0.032). The 5-year disease-specific survival of T2a was better than that of T2b tumors (74.8% vs. 65.4%, p = 0.019). There was no significant survival difference in T2a between extended cholecystectomy and simple cholecystectomy with lymph node dissection (81.8% vs. 73.7%, p = 0.361). However; there was a better survival trend for T2b tumor after extended cholecystectomy (71.7% vs. 59.3%, p = 0.057). Adjuvant chemotherapy was associated with improved survival for patients with lymph node metastasis in T2a (72.1% vs. 56.9; p = 0.022) and in T2b (68.2 vs. 48.5; p < 0.001). Multivariate analysis revealed that lymph node metastasis was the only significant poor prognostic factor (Hazard ratio 3.222; 95% confidential interval 1.960–4.489; p < 0.001). Conclusions: For T2 GBC; tumor location was not an independent prognostic factor. Lymph node metastasis was a significant poor prognostic factor and adjuvant chemotherapy should be considered for the patients with lymph node metastasis.

A predictive nomogram for lymph node metastasis of incidental gallbladder cancer: a SEER population-based study

BACKGROUND

Existing imaging techniques have a low ability to detect lymph node metastasis (LNM) of gallbladder cancer (GBC). Gallbladder removal by laparoscopic cholecystectomy can provide pathological information regarding the tumor itself for incidental gallbladder cancer (IGBC). The purpose of this study was to identify the risk factors associated with LNM of IGBC and to establish a nomogram to improve the ability to predict the risk of LNM for IGBC.

METHODS

A total of 796 patients diagnosed with stage T1/2 GBC between 2004 and 2015 who underwent surgery and lymph node evaluation were enrolled in this study. We randomly divided the dataset into a training set (70%) and a validation set (30%). A logistic regression model was used to construct the nomogram in the training set and then was verified in the validation set. Nomogram performance was quantified with respect to discrimination and calibration.

RESULTS

The rates of LNM in T1a, T1b and T2 patients were 7, 11.1 and 44.3%, respectively. Tumor diameter, T stage, and tumor differentiation were independent factors affecting LNM. The C-index and AUC of the training set were 0.718 (95% CI, 0.676-0.760) and 0.702 (95% CI, 0.659-0.702), respectively, demonstrating good prediction performance. The calibration curves showed perfect agreement between the nomogram predictions and actual observations. Decision curve analysis showed that the LNM nomogram was clinically useful when the risk was decided at a possibility threshold of 2-63%. The C-index and AUC of the validation set were 0.73 (95% CI: 0.665-0.795) and 0.692 (95% CI: 0.625-0.759), respectively.

CONCLUSION

The nomogram established in this study has good prediction ability. For patients with IGBC requiring re-resection, the model can effectively predict the risk of LNM and make up for the inaccuracy of imaging.

Prognostic Evaluation for Patients over 45 Years Old with Gallbladder Adenocarcinoma Resection: A SEER-Based Nomogram Analysis

Gallbladder adenocarcinoma is the main histopathological type of gallbladder cancer (GBC), so it is particularly important to understand its biological characteristics. Due to the low incidence of this type of cancer, there are few studies with large sample sizes. The log of positive lymph nodes (LODDS) has been evaluated by many scholars as a lymph node stage that may play a better role than the 8^th edition of the American Joint Committee on Cancer (AJCC) lymph node staging system in many cancers. However, the effect of LODDS has not been proven in gallbladder adenocarcinoma. Our research aimed to identify independent prognostic factors that are closely related to overall survival (OS) in patients with gallbladder adenocarcinoma over 45 years of age using data from the Surveillance, Epidemiology and, End Results (SEER) database. All patients were randomly divided into a modeling cohort and an internal validation cohort. Seven independent prognostic factors associated with OS—age, marital status, grade, tumor size, AJCC 8^th edition T stage and M stage, and LODDS—were used to build a nomogram to predict 1-, 3-, and 5-year survival. The C-index of our nomogram was 0.735 (95% CI, 0.716 to 0.754), and together with the calibration curve and ROC curve validation, the results confirmed the prediction effect of our nomogram. We believe that our nomogram will be an accurate and convenient method for patient prognosis assessment in the future.