Neoadjuvant Chemotherapy for Advanced Gallbladder Cancer: Do We have Enough Evidence? A Systematic Review

Incidence and management of gallbladder cancer in cholecystectomy specimens: a 5-year tertiary centre experience

BACKGROUND

Gallbladder cancer (GBC) is an uncommon, but highly aggressive cancer. Half of these cases are diagnosed pre-operatively, and the remaining cases are discovered incidentally on post-cholecystectomy specimens. There is a significant geographical variability in GBC incidence, with increasing age, female sex, and prolonged duration of cholelithiasis being risk factors for GBC. The primary aim was to define the overall local incidence of GBC incidental GBC and management of these cases. The secondary aim was to determine any pertinent risk factors in our case population.

METHODS

A retrospective observational study was performed on all the cholecystectomy specimens at the Gold Coast Hospital and Health Service from 1 January 2016 to 2 December 2021. Data was collected via the electronic medical record. The incidence and management of gallbladder cancers was calculated, and association with body mass index (BMI), smoking status, diabetes, inflammatory bowel disease (IBD) was identified.

RESULTS

3904 cholecystectomy specimens were reviewed. GBC was identified in 0.46% of cholecystectomies. 50% of these cases were found incidentally. Abdominal pain was the most common presenting complaint (94.4%). GBC was associated with increased age and BMI and female sex. There was no association between smoking status, diabetes or IBD with an increased incidence of cancer. Tumour staging guided surgical and/or adjuvant chemotherapy.

CONCLUSION

GBC is rare. Patients with symptoms are associated with a poor prognosis. Incidental cancers are common, and negative margin resection based on the T stage of the cancer is the most reliable curative option.

Gallbladder cancer mimicking perihilar cholangiocarcinoma-considerable rate of postoperative reclassification with implications for prognosis

BACKGROUND

For some patients undergoing resection under the suspicion of a perihilar cholangiocarcinoma (pCCA), postoperative diagnosis may differ from the preoperative diagnosis. While a postoperative finding of benign bile duct stricture is known to affect 3-15% of patients, less has been described about the consequences of finding other biliary tract cancers postoperatively. This study compared pre- and postoperative diagnoses, risk characteristics, and outcomes after surgery for suspected pCCA.

METHODS

Retrospective single-center study, Karolinska University Hospital, Stockholm, Sweden (January 2009-May 2017). The primary postoperative outcome was overall survival. Secondary outcomes were disease-free survival and postoperative complications. Survival analysis was performed by the Kaplan-Meier method.

RESULTS

Seventy-one patients underwent resection for suspected pCCA. pCCA was confirmed in 48 patients (68%). Ten patients had benign lesions (14%), 2 (3%) were diagnosed with other types of cholangiocarcinoma (CCA, distal n = 1, intrahepatic n = 1), while 11 (15%) were diagnosed with gallbladder cancer (GBC). GBC patients were older than patients with pCCA (median age 71 versus 58 years, p = 0.015), with a large proportion of patients with a high tumor extension stage (≥ T3, 91%). Median overall survival was 20 months (95% CI 15-25 months) for patients with pCCA and 17 months (95% CI 11-23 months) for patients with GBC (p = 0.135). Patients with GBC had significantly shorter median disease-free survival (DFS), 10 months (95% CI 3-17 months) compared 17 months (95% CI 15-19 months) for patients with pCCA (p = 0.010).

CONCLUSIONS

At a large tertiary referral center, 15% of patients resected for suspected pCCA were postoperatively diagnosed with GBC. Compared to patients with pCCA, GBC patients were older, with advanced tumors and shorter DFS. The considerable rate of re-classification stresses the need for improved preoperative staging, as these prognostic differences could have implications for treatment strategies.

Differential diagnoses of gallbladder tumors using CT-based deep learning

Background

The differential diagnosis between gallbladder cancer (GBC) and xanthogranulomatous cholecystitis (XGC) remains quite challenging, and can possibly lead to improper surgery. This study aimed to distinguish between XGC and GBC by combining computed tomography (CT) images and deep learning (DL) to maximize the therapeutic success of surgery.

Methods

We collected a dataset, including preoperative CT images, from 28 cases of GBC and 21 XGC patients undergoing surgery at our facility. It was subdivided into training and validation (n = 40), and test (n = 9) datasets. We built a CT patch-based discriminating model using a residual convolutional neural network and employed 5-fold cross-validation. The discriminating performance of the model was analyzed in the test dataset.

Results

Of the 40 patients in the training dataset, GBC and XGC were observed in 21 (52.5%), and 19 (47.5%) patients, respectively. A total of 61 126 patches were extracted from the 40 patients. In the validation dataset, the average sensitivity, specificity, and accuracy were 98.8%, 98.0%, and 98.5%, respectively. Furthermore, the area under the receiver operating characteristic curve (AUC) was 0.9985. In the test dataset, which included 11 738 patches, the discriminating accuracy for GBC patients after neoadjuvant chemotherapy (NAC) (n = 3) was insufficient (61.8%). However, the discriminating model demonstrated high accuracy (98.2%) and AUC (0.9893) for cases other than those receiving NAC.

Conclusion

Our CT-based DL model exhibited high discriminating performance in patients with GBC and XGC. Our study proposes a novel concept for selecting the appropriate procedure and avoiding unnecessary invasive measures.