Association of CT Findings With Perineural Invasion in Gallbladder Cancer: Preliminary Assessment.

Perineural invasion (PNI) indicates a worse prognosis for patients with gallbladder cancer (GBC). This preliminary retrospective study included 19 patients with GBC who under-went contrast-enhanced CT in the 4 weeks before undergoing surgical resection. GBC showed PNI on pathologic assessment in eight of 19 patients. On CT, wall thickening morphology had sensitivity of 75.0% and specificity of 81.8% for PNI; soft-tissue stranding around the celiac plexus had sensitivity of 62.5% and specificity of 100.0% for PNI.

Optimal radiological gallbladder lesion characterization by combining visual assessment with CT-based radiomics.

OBJECTIVES: Differentiating benign gallbladder diseases from gallbladder cancer (GBC) remains a radiological challenge because they can appear very similar on imaging. This study aimed at investigating whether CT-based radiomic features of suspicious gallbladder lesions analyzed by machine learning algorithms could adequately discriminate benign gallbladder disease from GBC. In addition, the added value of machine learning models to radiological visual CT-scan interpretation was assessed. METHODS: Patients were retrospectively selected based on confirmed histopathological diagnosis and available contrast-enhanced portal venous phase CT-scan. The radiomic features were extracted from the entire gallbladder, then further analyzed by machine learning classifiers based on Lasso regression, Ridge regression, and XG Boosting. The results of the best-performing classifier were combined with radiological visual CT diagnosis and then compared with radiological visual CT assessment alone. RESULTS: In total, 127 patients were included: 83 patients with benign gallbladder lesions and 44 patients with GBC. Among all machine learning classifiers, XG boosting achieved the best AUC of 0.81 (95% CI 0.72-0.91) and the highest accuracy rate of 73% (95% CI 65-80%). When combining radiological visual interpretation and predictions of the XG boosting classifier, the highest diagnostic performance was achieved with an AUC of 0.98 (95% CI 0.96-1.00), a sensitivity of 91% (95% CI 86-100%), a specificity of 93% (95% CI 90-100%), and an accuracy of 92% (95% CI 90-100%). CONCLUSIONS: Machine learning analysis of CT-based radiomic features shows promising results in discriminating benign from malignant gallbladder disease. Combining CT-based radiomic analysis and radiological visual interpretation provided the most optimal strategy for GBC and benign gallbladder disease differentiation. KEY POINTS: Radiomic-based machine learning algorithms are able to differentiate benign gallbladder disease from gallbladder cancer. Combining machine learning algorithms with a radiological visual interpretation of gallbladder lesions at CT increases the specificity, compared to visual interpretation alone, from 73 to 93% and the accuracy from 85 to 92%. Combined use of machine learning algorithms and radiological visual assessment seems the most optimal strategy for GBC and benign gallbladder disease differentiation.

Histological examination of the gallbladder following routine cholecystectomy? A selective analysis is justified.

BACKGROUND: It was hitherto common practice to analyse each removed gallbladder for the presence of gall bladder cancer (GBC) although this approach may be questioned. The aim of this study was to determine whether a policy of selective histopathological analysis (Sel-HPA) is oncologically safe and cost effective. METHODS: This retrospective study was conducted in a single Dutch teaching hospital. Immediately following cholecystectomy, the surgeon decided on the basis of inspection and palpation whether histological examination was indicated. The Dutch Comprehensive Cancer Organisation (IKNL) registry was used to identify the number of GBC during this time period. RESULTS: Of 2271 patients who underwent a cholecystectomy in our institution between January 2012 and December 2017, 1083 (47.7%) were deemed indicated for histopathological analysis. Sixteen pathological gallbladders (1.5%) were identified in that period (intestinal metaplasia, n = 3; low grade dysplasia n = 7; carcinoma n = 6). During follow-up, no patient was found to have GBC recurrence in the population whose gallbladder was not sent for pathology (52.3%, n = 1188, median 49 months of follow up). The percentage of gallbladders that were analysed decreased over the six years of observation from 83% to 38%. Our policy of Sel-HP saved over €65 000. CONCLUSIONS: A policy of selective histopathology after cholecystectomy is oncologically safe and reduces costs.

Routine Pathology and Postoperative Follow-Up are Not Cost-Effective in Cholecystectomy for Benign Gallbladder Disease.

INTRODUCTION: The incidence of gallstone disease is increasing and represents a strain on healthcare systems worldwide. Following cholecystectomy, gallbladder specimens are generally submitted for histopathologic examination and the diagnostic yield of this strategy remains questionable. This study aimed to evaluate the usefulness of routine pathologic examination of the gallbladder specimens and investigate the results of routine postoperative follow-up visits. METHODS: All cholecystectomies performed between January 2011 and July 2017 at a single center were evaluated. All gallbladder specimens were routinely pathologically examined. The outcome parameters were the macro- and microscopic gallbladder anomalies at pathology and the reported symptoms during routine follow-up visits 2-6 weeks after surgery. RESULTS: In the study period a total of 2763 patients underwent cholecystectomy, of which 2615 had a postoperative visit in the outpatient clinic. Seventy-three patients (3%) complained of persistent abdominal pain, and 29 of these patients were referred for further treatment, resulting in a resolution of symptoms in 97%. Of all gallbladder specimens, 199 (7%) displayed macroscopic anomalies and in four (2%) of these, gallbladder carcinoma was diagnosed. DISCUSSION: Selective pathologic examination of gallbladder specimens in case of macroscopic anomalies appears justified. Also routine follow-up after cholecystectomy appears not useful since 97% of patients do not report any symptoms at follow-up. A selective pathology and follow-up strategy could save significant healthcare costs.

Efficacy and safety assessment of ERCP in patients with malignant biliary obstruction.

BACKGROUND: To assess the efficacy and safety of Endoscopic retrograde cholangiopancreatography (ERCP) for malignant biliary obstruction (MBO). MATERIAL AND METHODS: A review of all ERCP-procedures performed at Akershus University Hospital during the six year period between 2009-2014 was analysed. Data for the period 2009- 2013 were obtained retrospectively and prospectively for 2014. Patients with jaundice due to MBO were selected for the present study. RESULTS: A total of 210 patients (51% females), median age of 70 years (range 33-96) were included. The total number of procedures were 314, whereof 218 (69%) were successful and 96 (31%) were failures. 292 procedures were palliative and 22 procedures were intended as 'bridge to surgery' whereof 15 patients underwent surgery. Pancreatic carcinoma occurred in 105 (50%) patients and was the most common reason for MBO. Straight plastic stents (I-stents) were applied in 145 (74%), double-pigtail stents (JJ-stents) in 29 (15%), self-expanding metal stent (SEMS) in 18 (9%) procedures and in 3 procedures (1.5%) an I-stent was inserted through an indwelling SEMS. Median duration of stentpatency in months was 2 (range 0-74) for I-stent, 1 (range 0-29) for JJ-stent and 4 (range 0-29) for SEMS. The rates of complication and mortality due to complication were 8.9% and 1.3% per procedure. CONCLUSION: Adequate drainage of MBO by ERCP was obtained in 69%. The rates of complication and procedure related mortality were at acceptable levels.

The use of real-time elastography in the assessment of gallbladder polyps: preliminary observations.

AIMS: Gallbladder polyps often have a benign nature. Current guidelines suggest surgical removal of polyps greater than 10 mm. However, the accuracy of the size criteria is limited because neoplasia can be found in gallbladder polyps less than 10 mm. The aim of this study was to evaluate the feasibility of real time elastography for gallbladder polyps and to demonstrate the elasticity properties of the polyps. MATERIAL AND METHOD: Fifty-three polypoid lesions of the gallbladder were prospectively examined with real-time elastography. Of these patients, 52 had a diagnosis of benign gallbladder polyps and one patient was accepted as a gallbladder carcinoma due to its clinical and radiological findings. B-mode and real-time elastographic images were simultaneously presented as a two-panel image, and the elastogram was displayed in a color scale that ranged from red (greatest strain, softest component), to green (average strain, intermediate component), to blue (no strain, hardest component). RESULTS: The mean size for benign gallbladder polyps was 7.2 +/- 3 mm (range, 5-21 mm). All benign gallbladder polyps on consecutive real-time elastographic images appeared as having a high-strain elastographic pattern. Only one patient who was accepted with gallbladder carcinoma had a gallbladder polyp with low elasticity properties. CONCLUSIONS: Our study showed that real time elastography of gallbladder polyps is feasible. This novel approach may be useful for the characterization of polypoid lesions of the gallbladder.

Cost effectiveness of routine laparoscopic ultrasound for assessment of resectability of gallbladder cancer.

BACKGROUND: In addition to a diagnostic laparoscopy (DL), a routine laparoscopic ultrasound (LUS) has been proposed to identify undetected hepatic metastases and/or anatomically advanced disease in patients with T2 or higher gall bladder cancer (GBC) patients planned for surgical resection. It was hypothesized that a routine LUS is not a cost-effective strategy for these patients. METHODS: Decision tree modeling was undertaken to compare DL-LUS vs. DL at the time of definitive resection of GBC (with no prior cholecystectomy). Costs in US dollars (payer's perspective), quality-adjusted life weeks (QALWs), and incremental cost-effectiveness ratios (ICER) were calculated (horizon: 6 weeks, willingness-to-pay: $1,000/QALW or $50,000/QALY). RESULTS: DL-LUS was cost effective at the base case scenario (costs: $30,838 for DL vs. $30,791 for DL-LUS and effectiveness 3.81 QALWs DL vs. 3.82 QALW DL-LUS), resulting in a cost reduction of $9,220 per quality-adjusted life week gained (or $479,469 per QALY). DL-LUS became less cost effective as the cost of ultrasound increased or the probability of exclusion from resection decreased. CONCLUSIONS: Routine LUS with DL for the assessment of resectability and exclusion of metastases is cost effective for patients with GBC. Until improvements in preoperative imaging occur to decrease the probability of exclusion, this appears to be a feasible strategy.

A prospective analysis of the preoperative assessment of duodenal involvement in gallbladder cancer.

BACKGROUND: Duodenal involvement occurs frequently in gallbladder cancer (GBC) as a result of the proximity of the duodenum to the gallbladder. METHODS: The study group included 74 GBC patients assessed between August 2009 and March 2011 in whom computed tomography (CT) of the abdomen indicated suspicion for duodenal involvement. RESULTS: Of 172 patients with resectable GBC, 74 (43.0%) had suspected duodenal involvement on imaging. Of these, 51 (68.9%) had suspected duodenal involvement on upper gastrointestinal endoscopy (UGIE). Symptoms of gastric outlet obstruction (GOO) were present in only 14 (18.9%) patients. Thirteen (17.6%) patients underwent staging laparoscopy alone. Of the 61 patients who underwent laparotomy, 31 (50.8%) were found to have actual duodenal involvement. The positive predictive value (PPV) of CT of the abdomen for duodenal involvement was 50.8% (31 of 61 patients). The addition of UGIE increased the PPV to 65.9% (27 of 41 patients). In the subgroup with evidence of duodenal mural thickening or mucosal irregularity on CT of the abdomen (n= 9) or duodenal mucosal infiltration on UGIE (n= 14), the PPV increased to 100%. A total of 33 (44.6%) patients underwent curative resection. The resectability rate was significantly lower in patients with symptoms of GOO [two of 14 (14.3%) vs. 31 of 60 (51.7%); P= 0.010], CT findings of duodenal mural thickening or mucosal irregularity compared with only loss of the fat plane [two of 12 (16.7%) vs. 31 of 62 (50.0%); P= 0.032], and UGIE evidence of duodenal infiltration compared with extrinsic compression or normal endoscopic findings [three of 16 (18.8%) vs. 18 of 35 (51.4%) and 12 of 23 (52.2%), respectively; P= 0.027 and P= 0.036, respectively]. CONCLUSIONS: Overall, CT of the abdomen demonstrated a PPV of 50.8% in detecting duodenal involvement, which increased to 65.9% with the addition of UGIE. The combined presence of GOO symptoms, CT findings of duodenal mural thickening and mucosal irregularity, and UGIE findings of infiltration of the duodenal mucosa significantly decreases resectability but does not preclude resection.

Hepatic functional reserve in patients with biliary malignancies: an assessment by technetium 99m galactosyl human serum albumin hepatic scintigraphy.

PROBLEM: Technetium 99m galactosyl human serum albumin (99mTc-GSA) is a hepatic scintigraphy agent that binds to the asialoglycoprotein receptors. We evaluated the clinical use of the scintigraphy for the pre-operative assessment of biliary malignancies. PATIENTS AND METHODS: Scintigraphy was performed before operation in 56 patients with biliary malignancies. A hepatic uptake ratio of 99mTc-GSA (LHL15; the count ratio of the liver to the sum of the heart and liver 15 min after injection of 99mTc-GSA) was calculated. RESULTS: LHL15 was significantly associated with bilirubin half-life in patients treated before operation with percutaneous transhepatic biliary drainage (P = 0.007). After operation, 4 of 18 patients with LHL15 < 0.925 died within 30 days. The postoperative mortality was significantly greater in patients with LHL15 < 0.925 than in patients with LHL15 > or = 0.925 (P = 0.033). CONCLUSION: 99mTc-GSA scintigraphy is useful in evaluating the hepatic functional reserve in patients with biliary malignancies.

[Clinical assessment of contrast-enhanced ultrasonography for the diagnosis of gall bladder diseases].

We evaluated the efficacy of contrast-enhanced ultrasonography (CEUS) with intra-arterial injection of CO2 microbubbles in 37 cases of gall bladder diseases. CEUS clearly visualized arterial flow and vascularity in every lesions without debris and gave us the precise information of vascular structure for the differential diagnosis of gall bladder tumors. For example, highly bifurcated tumor vessels and strong enhancement was observed in gall bladder cancer and we could detect relatively strong enhancement along the lumen with lack of enhancement of Rokitansky-Aschoff sinus in localized-type adenomyomatosis. Though CEUS is now an invasive modality, it will enable us to understand the non-invasive modality such as color doppler imaging with intra-venous administration of microbubbles in the future.

[The value of Doppler ultrasonography in gastroenterology: limitations and possibilities in the assessment of portal venous hypertension and in tumor diagnosis]. / Die Bedeutung der Dopplersonographie in der Gastroenterologie: Grenzen und Möglichkeiten bei der Abklärung der portalvenösen Hypertonie und in der Tumordiagnostik.

Due to technical progress, duplex sonography is growing in diagnostic value in gastrointestinal imaging. Color and pulsed spectral Doppler are the methods of choice in making information on morphologic and physiologic aspects of blood flow available. Amongst the various gastroenterologic applications, two important features are presented and discussed: investigation of the mesenterico-spleno-portal axis in patients with portal venous hypertension, and contributions to evaluation of primary and secondary liver tumors.

Improved delineation of the gallbladder wall with ultrasonography: its value in assessment of the depth of carcinoma invasion.

We examined 30 surgically removed gallbladders with ultrasound using a 10 MHz transducer in a water bath. The sonographic structure of gallbladder wall was imaged as 5 layers. The layer 3, a well-defined hyperechoic zone, was confirmed histologically as corresponding to the boundary between subserosa and muscularis. Since the spreading of gallbladder carcinoma beyond the muscle coat is an important prognostic indicator, high resolution images may well be used to advantage in assessing gallbladder wall penetration intraoperatively, enabling the surgeon to choose the proper operative procedure.

[Sonographic assessment of the extent of colonic wall lesions exemplified by colonic tumors]. / Sonographische Beurteilung des Ausmasses von Kolonwandläsionen am Beispiel von Kolontumoren.

In order to reveal sonographic accuracy in imaging gut wall lesions transcutaneous ultrasonic findings in 78 colonic wall tumours (6 polyps sized more than 1 cm, 68 colonic carcinomas, 1 pancreatic carcinoma, 1 gallbladder carcinoma and 2 benign diverticulitis tumours) were staged according or similar to TNM classification from 1987 and compared to histologic findings. 62 ultrasonic stagings were correct, sensitivity and specificity of U/T1 to U/T4 stagings ranged from 0.64 to 0.89 resp. 0.7 to 1.0. Thus, in the example of colonic tumours (of either dignity) ultrasound not only shows quality differences as gut wall lesions, but also images depth of invasion as a quantitative feature in gut wall lesions with acceptable accuracy.