The optimal extent of surgery in T2 gallbladder cancer and the need for hepatectomy: A meta-analysis

Prognostic analysis of lymph node resection and liver resection for T1b and T2 gallbladder cancer: a multi-center retrospective study

BACKGROUND

Survival benefit of extended cholecystectomy including lymph node resection (LNR) and liver resection (LR) is still debating.

METHODS

Patients pathologically diagnosed with T1b and T2 stage GBC in 6 medical centers from 2012 to 2022 were included and retrospectively analyzed. Clinical variables, including patient characteristics, overall survival (OS), disease-free survival (DFS), surgical approaches, and adjuvant treatments were collected. Propensity score-matching was performed to compare the survival outcomes.

RESULTS

A total of 160 T1b/T2 GBC patients were included. 52 patients undergoing LNR were matched to 54 patients without LNR. After matching, LNR demonstrated significant survival benefit in OS (mOS 48.8 months vs not reached; p = 0.020) and DFS (mDFS 47.9 months vs 70.2 months; p = 0.038). Meanwhile, 61 patients undergoing LR were matched to 54 patients without LR. After matching, LR demonstrated no statistical difference in overall survival (mOS 68.2 months vs 78.5 months; p = 0.72) and disease-free survival (mDFS 67.1 months vs 42.6 months; p = 0.30).

CONCLUSIONS

Our results revealed that pathological T1b and T2 GBC patients benefit from radical cholecystectomy including lymph node resection and may not benefit from liver resection.

Recurrence patterns and prediction of survival after recurrence for gallbladder cancer

BACKGROUND

Gallbladder cancer (GBC) is associated with a poor prognosis. Recurrence patterns and their effect on survival remain ill-defined. This study aimed to analyze recurrence patterns and develop a machine learning (ML) model to predict survival after recurrence (SAR) of GBC.

METHODS

Patients who underwent curative-intent resection of GBC between 1999 and 2022 were identified using an international database. An Extreme Gradient Boosting ML model to predict SAR was developed and validated.

RESULTS

Among 348 patients, 110 (31.6%) developed disease recurrence during follow-up. The most common recurrence site was local (29.1%), followed by multiple site (26.4%), liver (21.8%), peritoneal (18.2%), and lung (0.05%). The median SAR was the longest in patients with lung recurrence (36.0 months), followed by those with local recurrence (15.7 months). In contrast, patients with peritoneal (8.9 months), liver (8.5 months), or multiple-site (6.4 months) recurrence had a considerably shorter SAR. Patients with multiple-site recurrence had a worse SAR than individuals with single-site recurrence (6.4 vs 11.10 months, respectively; P =.014). The model demonstrated good performance in the evaluation and bootstrapping cohorts (area under the receiver operating characteristic curve: 71.4 and 71.0, respectively). The most influential variables were American Society of Anesthesiologists classification, local recurrence, receipt of adjuvant chemotherapy, American Joint Committee on Cancer T and N categories, and developing early disease recurrence (<12 months). To enable clinical applicability, an easy-to-use calculator was made available (https://catalano-giovanni.shinyapps.io/SARGB).

CONCLUSION

Except for lung recurrence, SAR for GBC was poor. A subset of patients with less aggressive disease biology may have favorable SAR. ML-based SAR prediction may help individuate candidates for curative re-resection when feasible.

Advantage of Log Odds of Metastatic Lymph Nodes After Curative-Intent Resection of Gallbladder Cancer

BACKGROUND

Lymph node metastasis (LNM) is among the most important predictors of poor prognosis after surgery for gallbladder cancer (GBC). Traditionally, staging has been based on the raw count of LNM, with a high risk of understaging patients who undergo inadequate lymph node dissection (LND). The log odds of metastatic lymph nodes (LODDS) may represent an alternative staging approach to stratify patients more accurately after resection of GBC.

PATIENTS AND METHODS

In this cross-sectional study, patients who underwent curative-intent surgery with LND for GBC were identified from an international database. Two predictive models were built and compared, each integrating a different lymph nodes status indicator [i.e., American Joint Committee on Cancer (AJCC) and LODDS].

RESULTS

Among 199 patients, the median number of lymph nodes examined was 5 [interquartile range (IQR): 3.0, 8.0]; most patients had T1 (n = 26, 13.1%) or T2 (n = 97, 48.7%) disease, and a subset had LNM (n = 87, 44.0%). Multivariable Cox analysis demonstrated LODDS was an independent predictor of overall survival [hazard ratio (HR) 1.84, 95% confidence interval (CI) 1.5-2.3; p < 0.001]. The LODDS model demonstrated better performance compared with a traditional model that utilized the AJCC N category [concordance (C) index: 0.814 versus 0.763; p < 0.001]. Patients classified as high- versus low-risk based on LODDS had much worse overall survival (OS) (4.9% versus 83.7%, respectively; p < 0.001). The LODDS model performance remained high even among patients with inadequate LND (< 6 LN) (C index: 0.87). An online calculator was developed ( https://catalano-giovanni.shinyapps.io/LoddsGBC/ ).

CONCLUSIONS

A novel prognostic model based on LODDS may overcome the inherent limitations of the current AJCC staging system, reducing understaging among patients with fewer than six total lymph nodes evaluated.

Role of Minimally Invasive Reoperation for Postoperatively Diagnosed T2 Gallbladder Cancer: Multicenter Retrospective Cohort Study

BACKGROUND

Although T2 gallbladder cancer (GBC) incidentally diagnosed after cholecystectomy requires additional resection, the surgical approaches are technically difficult due to inflammatory adhesion or fibrosis around the hepatoduodenal ligament and gallbladder bed. In this study, we sought to compare the surgical and oncologic outcomes of open and minimally invasive reoperation for postoperatively diagnosed T2 GBC.

STUDY DESIGN

Patients who underwent open (110) and laparoscopic (38) reoperation for T2 GBC between November 2004 and October 2022 at 5 tertiary referral centers were included in this multicenter retrospective cohort study. The short- and long-term outcomes were compared between the 2 groups.

RESULTS

There were no differences in clinicopathologic characteristics between the open and laparoscopic groups. Liver resection was more frequent in the open group (101 [91.8%] vs 21 [55.3%], p < 0.001). Compared with open operation, laparoscopic reoperation was associated with shorter postoperative hospital stay (9.0 [8.0 to 10.0] vs 6.0 [3.8 to 8.3] days, p < 0.001) and a lower postoperative complication rate (24 [21.8%] vs 1 [2.6%], p = 0.013). Among patients who underwent liver resection, the postoperative hospital stay was shorter in the laparoscopic group (9.0 [8.0 to 10.0] vs 6.0 [4.0 to 9.0] days, p = 0.004). The 5-year disease-free survival (66.7% vs 76.1%, p = 0.749) and overall survival (75.2% vs 73.7%, p = 0.789) rates were not significantly different between the 2 groups.

CONCLUSIONS

The results indicate that laparoscopic reoperation for postoperatively diagnosed T2 GBC has favorable postoperative outcomes and similar oncologic safety compared with open operation.

Laparoscopic Reoperation for Postoperatively Diagnosed Gallbladder Cancer: Technical Options for Cystic Duct Management

BACKGROUND

Gallbladder cancer is a rare disease with poor prognosis, for which surgical resection is considered the only curative treatment.1 The widespread adoption of laparoscopic cholecystectomy for benign biliary diseases has led to an increased incidence of postoperatively diagnosed gallbladder cancer.2-5 Several studies have proposed that tumors exceeding stage T2 require additional resection.3,6,7 However, reoperation for postoperatively diagnosed gallbladder cancer is technically difficult due to inflammatory adhesion or fibrosis around the hepatoduodenal ligament and gallbladder bed.8,9 For such reasons, there are limited evidence regarding the safety and feasibility of laparoscopic reoperation and no clear indications for when to perform minimally invasive surgery.

METHODS

In this multimedia article, we present the laparoscopic reoperation techniques for postoperatively diagnosed gallbladder cancer. We focus specifically on various approaches to surgically manage the cystic duct stump, depending on the length of remnant stump, degree of surrounding fibrosis, and margin status.

RESULTS

We represent three cases with different approaches. In the first case, a patient with a long remnant stump is managed with clip ligation and resection of the stump. Second, a patient with a short remnant stump and severe fibrosis is treated with stump excision and suture closure. Lastly, bile duct resection is performed for a patient with margin involvement during the initial operation.

CONCLUSIONS

Various technical options exist to approach the remnant cystic duct stump during laparoscopic reoperation for postoperatively diagnosed gallbladder cancer.

Machine learning prediction of early recurrence after surgery for gallbladder cancer

BACKGROUND

Gallbladder cancer is often associated with poor prognosis, especially when patients experience early recurrence after surgery. Machine learning may improve prediction accuracy by analysing complex non-linear relationships. The aim of this study was to develop and evaluate a machine learning model to predict early recurrence risk after resection of gallbladder cancer.

METHODS

In this cross-sectional study, patients who underwent resection of gallbladder cancer with curative intent between 2001 and 2022 were identified using an international database. Patients were assigned randomly to a development and an evaluation cohort. Four machine learning models were trained to predict early recurrence (within 12 months) and compared using the area under the receiver operating curve (AUC).

RESULTS

Among 374 patients, 56 (15.0%) experienced early recurrence; most patients had T1 (51, 13.6%) or T2 (180, 48.1%) disease, and a subset had lymph node metastasis (120, 32.1%). In multivariable Cox analysis, resection margins (HR 2.34, 95% c.i. 1.55 to 3.80; P < 0.001), and greater AJCC T (HR 2.14, 1.41 to 3.25; P < 0.001) and N (HR 1.59, 1.05 to 2.42; P = 0.029) categories were independent predictors of early recurrence. The random forest model demonstrated the highest discrimination in the evaluation cohort (AUC 76.4, 95% c.i. 66.3 to 86.5), compared with XGBoost (AUC 74.4, 53.4 to 85.3), support vector machine (AUC 67.2, 54.4 to 80.0), and logistic regression (AUC 73.1, 60.6 to 85.7), as well as good accuracy after bootstrapping validation (AUC 75.3, 75.0 to 75.6). Patients classified as being at high versus low risk of early recurrence had much worse overall survival (36.1 versus 63.8% respectively; P < 0.001). An easy-to-use calculator was made available (https://catalano-giovanni.shinyapps.io/GallbladderER).

CONCLUSION

Machine learning-based prediction of early recurrence after resection of gallbladder cancer may help stratify patients, as well as help inform postoperative adjuvant therapy and surveillance strategies.

Prognostic Effect of Liver Resection in Extended Cholecystectomy for T2 Gallbladder Cancer Revisited: A Retrospective Cohort Study With Propensity Score-matched Analysis

OBJECTIVE

This study aimed to evaluate the effect of liver resection on the prognosis of T2 gallbladder cancer (GBC).

BACKGROUND

Although extended cholecystectomy [lymph node dissection (LND) + liver resection] is recommended for T2 GBC, recent studies have shown that liver resection does not improve survival outcomes relative to LND alone.

METHODS

Patients with pT2 GBC who underwent extended cholecystectomy as an initial procedure and did not reoperation after cholecystectomy at 3 tertiary referral hospitals between January 2010 and December 2020 were analyzed. Extended cholecystectomy was defined as either LND with liver resection (LND+L group) or LND only (LND group). We conducted 2:1 propensity score matching to compare the survival outcomes of the groups.

RESULTS

Of the 197 patients enrolled, 100 patients from the LND+L group and 50 from the LND group were successfully matched. The LND+L group experienced greater estimated blood loss ( P <0.001) and a longer postoperative hospital stay ( P =0.047). There was no significant difference in the 5-year disease-free survival (DFS) of the 2 groups (82.7% vs 77.9%, respectively, P =0.376). A subgroup analysis showed that the 5-year DFS was similar in the 2 groups in both T substages (T2a: 77.8% vs 81.8%, respectively, P =0.988; T2b: 88.1% vs 71.5%, respectively, P =0.196). In a multivariable analysis, lymph node metastasis [hazard ratio (HR) 4.80, P =0.006] and perineural invasion (HR 2.61, P =0.047) were independent risk factors for DFS; liver resection was not a prognostic factor (HR 0.68, P =0.381).

CONCLUSIONS

Extended cholecystectomy including LND without liver resection may be a reasonable treatment option for selected T2 GBC patients.

Wedge resection versus segment IVb and V resection of the liver for T2 gallbladder cancer: a systematic review and meta-analysis

Objectives

Although guidelines recommend extended cholecystectomy for T2 gallbladder cancer (GBC), the optimal hepatectomy strategy remains controversial. The study aims to compare the prognosis of T2 GBC patients who underwent wedge resection (WR) versus segment IVb and V resection (SR) of the liver.

Methods

A specific search of online databases was performed from May 2001 to February 2023. The postoperative efficacy outcomes were synthesized and meta-analyses were conducted.

Results

A total of 9 studies involving 2,086 (SR = 627, WR = 1,459) patients were included in the study. The primary outcomes included disease-free survival (DFS) and overall survival (OS). For DFS, the 1-year DFS was statistically higher in patients undergoing SR than WR [risk ratio (RR) = 1.07, 95% confidence interval (CI) = 1.02-1.13, P = 0.007]. The 3-year DFS (P = 0.95), 5-year DFS (P = 0.77), and hazard ratio (HR) of DFS (P = 0.72) were similar between the two groups. However, the 3-year OS was significantly lower in patients who underwent SR than WR [RR = 0.90, 95% CI = 0.82-0.99, P = 0.03]. Moreover, SR had a higher hazard HR of OS [HR = 1.33, 95% CI = 1.01-1.75, P = 0.04]. No significant difference was found in 1-year (P = 0.32) and 5-year (P = 0.9) OS. For secondary outcomes, patients who received SR tended to develop postoperative complications (POC) [RR = 1.90, 95% CI = 1.00-3.60, P = 0.05]. In addition, no significant differences in intrahepatic recurrence (P = 0.12) were observed.

Conclusions

In conclusion, SR can improve the prognosis of T2 GBC patients in DFS. In contrast to WR, the high HR and complications associated with SR cannot be neglected. Therefore, surgeons should evaluate the condition of the patients and take their surgical skills into account when selecting SR.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier, CRD42022362974.

Gallbladder cancer

Gallbladder cancer (GBC) is the most common cancer of the biliary tract, characterized by a very poor prognosis when diagnosed at advanced stages owing to its aggressive behaviour and limited therapeutic options. Early detection at a curable stage remains challenging because patients rarely exhibit symptoms; indeed, most GBCs are discovered incidentally following cholecystectomy for symptomatic gallbladder stones. Long-standing chronic inflammation is an important driver of GBC, regardless of the lithiasic or non-lithiasic origin. Advances in omics technologies have provided a deeper understanding of GBC pathogenesis, uncovering mechanisms associated with inflammation-driven tumour initiation and progression. Surgical resection is the only treatment with curative intent for GBC but very few cases are suitable for resection and most adjuvant therapy has a very low response rate. Several unmet clinical needs require to be addressed to improve GBC management, including discovery and validation of reliable biomarkers for screening, therapy selection and prognosis. Standardization of preneoplastic and neoplastic lesion nomenclature, as well as surgical specimen processing and sampling, now provides reproducible and comparable research data that provide a basis for identifying and implementing early detection strategies and improving drug discovery. Advances in the understanding of next-generation sequencing, multidisciplinary care for GBC, neoadjuvant and adjuvant strategies, and novel systemic therapies including chemotherapy and immunotherapies are gradually changing the treatment paradigm and prognosis of this recalcitrant cancer.