Risk score for malignancy in patients with suspicious gallbladder lesions: Retrospective analysis of 175 cases

BACKGROUND

Among cancers, carcinoma gallbladder has one of the most dismal prognosis. Early lesions are difficult to biopsy because of proximity to luminal structures and risk of biliary peritonitis. However, early surgery offers the only chance of a complete cure. Utilizing a risk score would allow characterization of the risk of malignancy and early referral to an oncology centre thereby resulting in better outcomes for patients with carcinoma gallbladder.

METHODS

The aim of this study was to develop a risk score for carcinoma in patients with suspicious gallbladder lesions based on clinical presentation and imaging. All patients with suspicious gallbladder lesions on radiological imaging who underwent surgery were analyzed. Patients were considered for scoring if the ultrasound showed the gallbladder wall thickening (more than 4 mm) and computed tomography scan showed operable disease. Statistical analysis was done to derive a score for malignancy.

RESULTS

Total 175 patients underwent an operation for suspicious gallbladder lesions from January 2005 to December 2014. The factors analyzed were clinical biochemical and imaging findings. Of these, 71 were benign on the final histopathology and 104 were malignant. The score was constructed with the following variables: female sex, high total bilirubin (≥ 1 mg/dL), presence of a mass, focal location of the lesion, presence of gallbladder stones and nodal involvement in the hepatoduodenal region on imaging. A model score and modified score were obtained. In this modified score, score of more than 8 out of 20 predicted malignancy with a sensitivity of 78% and specificity of 70.4%. Receiver operating characteristic (ROC) curve constructed with these variables had an area under curve of 0.828. There was no statistically significant difference between the model score and the modified score.

CONCLUSIONS

A pre-operative risk score was obtained for carcinoma gallbladder, which needs to be validated prospectively in future.

Risk of developing gallbladder cancer in patients with gallbladder polyps detected on transabdominal ultrasound: a systematic review and meta-analysis

OBJECTIVE

To estimate the risk of malignancy in gallbladder polyps of incremental sizes detected during transabdominal ultrasound (TAUS).

METHODS

We searched databases including MEDLINE, Embase, and Cochrane Library for eligible studies recording the polyp size from which gallbladder malignancy developed, confirmed following cholecystectomy, or by subsequent follow-up. Primary outcome was the risk of gallbladder cancer in patients with polyps. Secondary outcome was the effect of polyp size as a prognostic factor for cancer. Risk of bias was assessed using the Quality in Prognostic Factor Studies (QUIPS) tool. Bayesian meta-analysis estimated the median cancer risk according to polyp size. This study is registered with PROSPERO (CRD42020223629).

RESULTS

82 studies published since 1990 reported primary data for 67,837 patients. 67,774 gallbladder polyps and 889 cancers were reported. The cumulative median cancer risk of a polyp measuring 10 mm or less was 0.60% (99% credible range 0.30-1.16%). Substantial heterogeneity existed between studies (I2 = 99.95%, 95% credible interval 99.86-99.98%). Risk of bias was generally high and overall confidence in evidence was low. 13 studies (15.6%) were graded with very low certainty, 56 studies (68.3%) with low certainty, and 13 studies (15.6%) with moderate certainty. In studies considered moderate quality, TAUS monitoring detected 4.6 cancers per 10,000 patients with polyps less than 10 mm.

CONCLUSION

Malignant risk in gallbladder polyps is low, particularly in polyps less than 10 mm, however the data are heterogenous and generally low quality. International guidelines, which have not previously modelled size data, should be informed by these findings.

ADVANCES IN KNOWLEDGE

This large systematic review and meta-analysis has shown that the mean cumulative risk of small gallbladder polyps is low, but heterogeneity and missing data in larger polyp sizes (>10 mm) means the risk is uncertain and may be higher than estimated.Studies considered to have better methodological quality suggest that previous estimates of risk are likely to be inflated.

Follow-up of gallbladder polyps in a high-risk population of gallbladder cancer: a cohort study and multivariate survival competing risk analysis

BACKGROUND

The risk of neoplasia in gallbladder polyps seems to be low, but the evidence from populations at high-risk of gallbladder cancer is limited. We aimed to estimate the risk and to identify the factors associated with neoplastic polyps in a high-risk Hispanic population.

METHODS

A retrospective cohort was recruited between January 2010 and December 2019 at a Chilean university center. Multivariate survival analyses were conducted. Fine-Gray models were fitted to account for competing risks. Covariate adjustment was conducted using propensity scores. The main outcome was the development of gallbladder adenomas or adenocarcinoma.

RESULTS

Overall, 748 patients were included, 59.6% underwent cholecystectomy. The median follow-up of patients not subjected to cholecystectomy was 54.7 months (12-128.6 months). Seventeen patients (2.27%) developed the outcome. After adjustment by age, sex, intralesional blood flow, lithiasis and gallbladder wall thickening, only polyp size (≥10 mm, adjusted-HR: 15.01, 95%CI: 5.4-48.2) and number of polyps (≥3 polyps, adjusted-HR: 0.11, 95%CI: 0.01-0.55) were associated with neoplasia.

CONCLUSION

In a Hispanic population at high-risk for gallbladder cancer, gallbladder polyps seem to have a low risk of neoplasia. Polyp size was the main risk factor, while having multiple polyps was associated with an underlying benign condition.

Contrast-enhanced ultrasound to assess gallbladder polyps

PURPOSE

To assess the value of contrast-enhanced ultrasound (CEUS) in distinguishing adenomatous gallbladder polyps from cholesterol gallbladder polyps.

METHODS

A total of 164 patients with gallbladder polyps were retrospectively analyzed. All patients underwent B-mode ultrasound (US) and CEUS before cholecystectomy. Gallbladder polyps were divided into cholesterol polyp group and adenomatous polyp group according to pathology. Differences in patient's age, gender, maximum polyp size, number, presence of gallstones, vascularity and stalk width measured by US and vascular stalk width measured by CEUS were tested between the two groups. The diagnostic performance of specific US features was evaluated. The independent factors related with adenomatous polyps were analyzed by multiple logistic regression analyses.

RESULTS

There were 114 cholesterol polyps and 50 adenomatous polyps in 164 patients analyzed in the study. Differences in maximum size, vascularity, and stalk width of the gallbladder polyp were significant between the two groups (p < 0.05), whereas differences in patient's age, gender, number of gallbladder polyp, and presence of gallstones between the two groups were not (p > 0.05). Stalk width was wider than vascular stalk width between the two groups (p < 0.05). Vascular stalk width was also statistically different between the two groups (p < 0.05). The diagnostic performance of vascular stalk width was more significant than stalk width. Only vascular stalk width and vascularity were independent factors related with adenomatous polyps.

CONCLUSION

Vascular stalk width measured by CEUS is more accurate than stalk width measured by grayscale US in distinguishing adenomatous polyps from cholesterol polyps.

Analysis of risk factors for gallbladder polyp formation - A retrospective study based on serial ultrasounds

AIM

To evaluate gallbladder polyp (GBP) formation related risk factors based on serial ultrasounds (US).

METHODS

Risk factors related GBP formation were retrospectively investigated among participants, who had US reexamination and interval >180 days in 5 years. After groups were divided based on US, we compared final data and initial data in GBP new incidence group. Then compared the data in GBP new incidence group and GBP(-) group.

RESULTS

Overall 20 447 participants were recruited, including 18 243 in GBP (-) group and 2204 in GBP group. The mean diameters of polyps were 0.455 ± 0.198 mm in initial and 0.420 ± 0.180 mm in final examination. GBP new incidence group included 797 participants. Percentage of GBP new incidence participants was higher than GBP resolved (36.16% vs. 11.71%). Participants in middle age were more likely have GBP size increase or new incidence, and participants in old age (≥60 years old) were with GBP size decrease or resolved. In GBP new incidence group, participants in final US showed higher FBG, higher LDL, lower HDL, higher ALT and higher AST than initial US. Compared with GBP (-) group and, same risk factors, in addition with age, were shown in GBP new incidence group, Logistic regression analysis show that higher LDL, lower HDL and higher AST were risk factors for GBP formation.

CONCLUSION

Participants in middle age were more likely to have GBP new incidence. Higher LDL, lower HDL and higher AST were independently risk factors for GBP formation.

Gallbladder Polyps: Real or Imagined?

The finding of gallbladder polyps on imaging studies prompts further workup. Imaging results are often discordant with final pathology. The goal of this study is to compare polypoid lesions of the gallbladder found on preoperative ultrasound (US) with final pathologic diagnosis after cholecystectomy to help guide clinical decision-making. A retrospective study was conducted identifying adult patients who were diagnosed with polyps via US and who underwent cholecystectomy from 2008 through 2015. Imaging data, final pathology, and demographics were manually reviewed. A total of 2290 cholecystectomy patients had US-based polyps. Of these, 1661 patients (73%) did not have polyps on final pathology; primarily, stones or sludge were identified. Adenomyosis was diagnosed in 61 patients (2.7%). A total of 556 patients (24.2%) had pathologic polypoid lesions with the following breakdown: 463 (20.2%) cholesterol polyps, 43 other benign polyps (1.8%), 40 adenomas (1.7%), and 10 adenocarcinomas (0.4%). All patients with adenocarcinoma were older than 40 years and 91 per cent had US findings of polyps >10 mm. Ultrasound alone is an unreliable method of detecting real gallbladder polyps. This large database study found a very low risk of cancer. Size on US and patient age should be considered in the selection of appropriate surgical candidates with sonographic “polyps.”

Primary squamous cell carcinoma of the gallbladder: Report of a rare neoplasm from the Eastern Province of Saudi Arabia

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There is paucity in the literature regarding gallbladder cancer in Saudi Arabia.

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Only 3% of gallbladder cancers worldwide are primary squamous cell carcinoma (SCC).

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We present the first case of primary gallbladder SCC reported in Saudi Arabia.

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Physicians should be aware of this cancer even if it is rare in our country.

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We should consider gallbladder cancer when diagnosing gallbladder-related symptoms.

Introduction

Primary squamous cell carcinoma of the gallbladder is extremely rare, and accounts for about 3% of all malignant gallbladder neoplasms.

Presentation of case

We report the case of a 58-year-old woman who presented with acute onset epigastric pain radiating to the back. The initial diagnosis, based on radiological images, was an incidental gallbladder mass with multiple gallstones. A staging laparoscopy was performed, followed by exploratory laparotomy with radical cholecystectomy. Segments 4b and 5 of the liver and the first part of the duodenum with the transverse colon were also resected. Histopathology of the gallbladder mass revealed invasive moderately differentiated squamous cell carcinoma with infiltration of liver segments 4b and 5, the first part of the duodenum, and two pericaval lymph nodes (with lymphovascular and perineural invasion). The primary tumour was scored as pT3, pN2, M1, stage IVB, based on the American Joint Committee on Cancer classification, version 7. The patient was discharged postoperatively and started adjuvant chemotherapy.

Discussion

The best option for treating early-stage gallbladder cancer is radical surgery, while adjuvant chemo-radiation can also be beneficial. Our patient did not exhibit the typical symptoms of gallbladder cancer, and radiography was required for her diagnosis. Thus, additional work is needed to improve the detection of squamous cell carcinoma to improve the prognosis of patients like our own.

Conclusion

Clinicians must be alert to the possibility of squamous cell gallbladder carcinoma, and gallbladder neoplasms should be among the possibilities considered during the differential diagnosis of symptoms related to the gallbladder.

Transabdominal ultrasound and endoscopic ultrasound for diagnosis of gallbladder polyps

BACKGROUND

Approximately 0.6% to 4% of cholecystectomies are performed because of gallbladder polyps. The decision to perform cholecystectomy is based on presence of gallbladder polyp(s) on transabdominal ultrasound (TAUS) or endoscopic ultrasound (EUS), or both. These polyps are currently considered for surgery if they grow more than 1 cm. However, non-neoplastic polyps (pseudo polyps) do not need surgery, even when they are larger than 1 cm. True polyps are neoplastic, either benign (adenomas) or (pre)malignant (dysplastic polyps/carcinomas). True polyps need surgery, especially if they are premalignant or malignant. There has been no systematic review and meta-analysis on the accuracy of TAUS and EUS in the diagnosis of gallbladder polyps, true gallbladder polyps, and (pre)malignant polyps.

OBJECTIVES

To summarise and compare the accuracy of transabdominal ultrasound (TAUS) and endoscopic ultrasound (EUS) for the detection of gallbladder polyps, for differentiating between true and pseudo gallbladder polyps, and for differentiating between dysplastic polyps/carcinomas and adenomas/pseudo polyps of the gallbladder in adults.

SEARCH METHODS

We searched the Cochrane Library, MEDLINE, Embase, Science Citation Index Expanded, and trial registrations (last date of search 09 July 2018). We had no restrictions regarding language, publication status, or prospective or retrospective nature of the studies.

SELECTION CRITERIA

Studies reporting on the diagnostic accuracy data (true positive, false positive, false negative and true negative) of the index test (TAUS or EUS or both) for detection of gallbladder polyps, differentiation between true and pseudo polyps, or differentiation between dysplastic polyps/carcinomas and adenomas/pseudo polyps. We only accepted histopathology after cholecystectomy as the reference standard, except for studies on diagnosis of gallbladder polyp. For the latter studies, we also accepted repeated imaging up to six months by TAUS or EUS as the reference standard.

DATA COLLECTION AND ANALYSIS

Two authors independently screened abstracts, selected studies for inclusion, and collected data from each study. The quality of the studies was evaluated using the QUADAS-2 tool. The bivariate random-effects model was used to obtain summary estimates of sensitivity and specificity, to compare diagnostic performance of the index tests, and to assess heterogeneity.

MAIN RESULTS

A total of 16 studies were included. All studies reported on TAUS and EUS as separate tests and not as a combination of tests. All studies were at high or unclear risk of bias, ten studies had high applicability concerns in participant selection (because of inappropriate participant exclusions) or reference standards (because of lack of follow-up for non-operated polyps), and three studies had unclear applicability concerns in participant selection (because of high prevalence of gallbladder polyps) or index tests (because of lack of details on ultrasound equipment and performance). A meta-analysis directly comparing results of TAUS and EUS in the same population could not be performed because only limited studies executed both tests in the same participants. Therefore, the results below were obtained only from indirect test comparisons. There was significant heterogeneity amongst all comparisons (target conditions) on TAUS and amongst studies on EUS for differentiating true and pseudo polyps.Detection of gallbladder polyps: Six studies (16,260 participants) used TAUS. We found no studies on EUS. The summary sensitivity and specificity of TAUS for the detection of gallbladder polyps was 0.84 (95% CI 0.59 to 0.95) and 0.96 (95% CI 0.92 to 0.98), respectively. In a cohort of 1000 people, with a 6.4% prevalence of gallbladder polyps, this would result in 37 overdiagnosed and seven missed gallbladder polyps.Differentiation between true polyp and pseudo gallbladder polyp: Six studies (1078 participants) used TAUS; the summary sensitivity was 0.68 (95% CI 0.44 to 0.85) and the summary specificity was 0.79 (95% CI 0.57 to 0.91). Three studies (209 participants) used EUS; the summary sensitivity was 0.85 (95% CI 0.46 to 0.97) and the summary specificity was 0.90 (95% CI 0.78 to 0.96). In a cohort of 1000 participants with gallbladder polyps, with 10% having true polyps, this would result in 189 overdiagnosed and 32 missed true polyps by TAUS, and 90 overdiagnosed and 15 missed true polyps by EUS. There was no evidence of a difference between the diagnostic accuracy of TAUS and EUS (relative sensitivity 1.06, P = 0.70, relative specificity 1.15, P = 0.12).Differentiation between dysplastic polyps/carcinomas and adenomas/pseudo polyps of the gallbladder: Four studies (1,009 participants) used TAUS; the summary sensitivity was 0.79 (95% CI 0.62 to 0.90) and the summary specificity was 0.89 (95% CI 0.68 to 0.97). Three studies (351 participants) used EUS; the summary sensitivity was 0.86 (95% CI 0.76 to 0.92) and the summary specificity was 0.92 (95% CI 0.85 to 0.95). In a cohort of 1000 participants with gallbladder polyps, with 5% having a dysplastic polyp/carcinoma, this would result in 105 overdiagnosed and 11 missed dysplastic polyps/carcinomas by TAUS and 76 overdiagnosed and seven missed dysplastic polyps/carcinomas by EUS. There was no evidence of a difference between the diagnostic accuracy of TAUS and EUS (log likelihood test P = 0.74).

AUTHORS' CONCLUSIONS

Although TAUS seems quite good at discriminating between gallbladder polyps and no polyps, it is less accurate in detecting whether the polyp is a true or pseudo polyp and dysplastic polyp/carcinoma or adenoma/pseudo polyp. In practice, this would lead to both unnecessary surgeries for pseudo polyps and missed cases of true polyps, dysplastic polyps, and carcinomas. There was insufficient evidence that EUS is better compared to TAUS in differentiating between true and pseudo polyps and between dysplastic polyps/carcinomas and adenomas/pseudo polyps. The conclusions are based on heterogeneous studies with unclear criteria for diagnosis of the target conditions and studies at high or unclear risk of bias. Therefore, results should be interpreted with caution. Further studies of high methodological quality, with clearly stated criteria for diagnosis of gallbladder polyps, true polyps, and dysplastic polyps/carcinomas are needed to accurately determine diagnostic accuracy of EUS and TAUS.

Polypoid lesions of the gallbladder: disease spectrum with pathologic correlation

Gallbladder polyps are seen on as many as 7% of gallbladder ultrasonographic images. The differential diagnosis for a polypoid gallbladder mass is wide and includes pseudotumors, as well as benign and malignant tumors. Tumefactive sludge may be mistaken for a gallbladder polyp. Pseudotumors include cholesterol polyps, adenomyomatosis, and inflammatory polyps, and they occur in that order of frequency. The most common benign and malignant tumors are adenomas and primary adenocarcinoma, respectively. Polyp size, shape, and other ancillary imaging findings, such as a wide base, wall thickening, and coexistent gallstones, are pertinent items to report when gallbladder polyps are discovered. These findings, as well as patient age and risk factors for gallbladder cancer, guide clinical decision making. Symptomatic polyps without other cause for symptoms, an age over 50 years, and the presence of gallstones are generally considered indications for cholecystectomy. Incidentally noted pedunculated polyps smaller than 5 mm generally do not require follow-up. Polyps that are 6-10 mm require follow-up, although neither the frequency nor the length of follow-up has been established. Polyps that are larger than 10 mm are typically excised, although lower size thresholds for cholecystectomy may be considered for patients with increased risk for gallbladder carcinoma, such as patients with primary sclerosing cholangitis.

Malignant transformation of a 5-mm gallbladder polyp over 2 years: a case report and review of current literature

Gallbladder polyps (GBPs) are incidentally seen in 4% to 7% of adults on abdominal ultrasounds. Most GBPs are benign cholesterol polyps, adenomyomatosis, or inflammatory polyps. Currently, cholecystectomy is widely accepted as appropriate care for polyps 10 mm or larger as they present a higher risk for malignancy. However, the management of small polyps smaller than 10 mm has continued to be a dilemma to clinicians and radiologists. Many authors support a nonoperative approach with imaging follow-up for polyps smaller than 10 mm, as most have been shown to be benign. However, small polyps do have the potential to be neoplastic adenomas and become malignant. In this report, we will describe a case of a tiny GBP that subsequently developed into a 20-mm carcinoma over a period of 2 years.

Gallbladder Cancer in the 21st Century

Gallbladder cancer (GBC) is an uncommon disease in the majority of the world despite being the most common and aggressive malignancy of the biliary tree. Early diagnosis is essential for improved prognosis; however, indolent and nonspecific clinical presentations with a paucity of pathognomonic/predictive radiological features often preclude accurate identification of GBC at an early stage. As such, GBC remains a highly lethal disease, with only 10% of all patients presenting at a stage amenable to surgical resection. Among this select population, continued improvements in survival during the 21st century are attributable to aggressive radical surgery with improved surgical techniques. This paper reviews the current available literature of the 21st century on PubMed and Medline to provide a detailed summary of the epidemiology and risk factors, pathogenesis, clinical presentation, radiology, pathology, management, and prognosis of GBC.

US characteristics for the prediction of neoplasm in gallbladder polyps 10 mm or larger

PURPOSE

To evaluate the characteristics of gallbladder polyps 10 mm or larger to predict a neoplasm in US examinations.

MATERIALS AND METHODS

Fifty-three patients with gallbladder polyps ≥ 10 mm with follow-up images or pathologic diagnosis were included in the retrospective study. All images and reports were reviewed to determine the imaging characteristics of gallbladder polyps. Univariate and multivariate analyses were used to evaluate predictors for a neoplastic polyp.

RESULTS

A neoplastic polyp was verified in 12 of 53 patients and the mean size was 13.9 mm. The univariate analysis revealed that adjacent gallbladder wall thickening, larger size (≥15 mm), older age (≥57 years), absence of hyperechoic foci in a polyp, CT visibility, sessile shape, a solitary polyp, and an irregular surface were significant predictors for a neoplastic polyp. In the multivariate analysis, larger size (≥15 mm) was a significant predictor for a neoplastic polyp.

CONCLUSION

A polyp size ≥15 mm was the strongest predictor for a neoplastic polyp with US. The hyperechoic foci in a polyp and CT visibility would be useful indicators for the differentiation of a neoplastic polyp, in addition to the established predictors.

KEY POINTS

• A polyp size ≥15 mm is the strongest predictor for a neoplastic polyp with US. • Hyperechoic foci in a polyp and CT visibility are new predictors. • The rate of malignancy is low in polyps even 10 mm or larger (15.1 %).

Role of aberrant PI3K pathway activation in gallbladder tumorigenesis

The PI3K/AKT pathway governs a plethora of cellular processes, including cell growth, proliferation, and metabolism, in response to growth factors and cytokines. By acting as a unique lipid phosphatase converting phosphatidylinositol-3,4,5,-trisphosphate (PIP3) to phosphatidylinositol-4,5,-bisphosphate (PIP2), phosphatase and tensin homolog (PTEN) acts as the major cellular suppressor of PI3K signaling and AKT activation. Recently, PI3K mutations and loss/mutation of PTEN have been characterized in human gallbladder tumors; whether aberrant PTEN/PI3K pathway plays a causal role in gallbladder carcinogenesis, however, remains unknown. Herein we show that in mice, deregulation of PI3K/AKT signaling is sufficient to transform gallbladder epithelial cells and trigger fully penetrant, highly proliferative gallbladder tumors characterized by high levels of phospho-AKT. Histopathologically, these mouse tumors faithfully resemble human adenomatous gallbladder lesions. The identification of PI3K pathway deregulation as both an early event in the neoplastic transformation of the gallbladder epithelium and a main mechanism of tumor growth in Pten heterozygous and Pten mutant mouse models provides a new framework for studying in vivo the efficacy of target therapies directed against the PI3K pathway, as advanced metastatic tumors are often addicted to “trunkular” mutations.

Upregulated plasma and urinary levels of nucleosides as biological markers in the diagnosis of primary gallbladder cancer

We first detected aberrant nucleoside levels in the plasma, urine, bile, and tissues from cases and controls to explore them as biomarkers in the diagnosis of gallbladder cancer. Reversed-phase high-performance liquid chromatography was used to assess the levels of ten nucleosides in these samples from gallbladder cancer patients, gallstone patients, and healthy controls. Plasma and urine samples were collected from patients with gallbladder cancer (n = 202), patients with gallstones (n = 203), and healthy controls (n = 205); bile and tissue samples were collected from 91 gallbladder cancer patients, 93 gallstone patients; and 90 were donated after cardiac death. Of the ten nucleosides analyzed, eight urinary nucleosides, five plasma nucleosides, three bile nucleosides, and one tissue nucleoside were significantly upregulated in the gallbladder cancer patients compared to control groups (p < 0.05). Among these upregulated nucleosides, the sensitivity, specificity, and accuracy of urinary nucleosides in the diagnosis of gallbladder cancer patients were 89.4, 97.1, and 95.7%, respectively, those of plasma nucleosides were 91.2, 95.6, and 94.2%, respectively, those of bile nucleosides were 95.3, 96.4, and 95.1%, respectively, and those of tissue nucleosides were 86.2, 93.8, and 92.6%, respectively. These results suggest that nucleosides may be as useful as biological markers for gallbladder cancer.

Primary gallbladder lymphoma presenting as a polyp

We present an unusual case of a 75-year-old woman, with no significant medical history, presenting with ongoing weight loss and change in bowel habit. Her physical examination and initial blood tests were all normal, and, therefore, radiographic imaging was undertaken. Ultrasound and CT of the abdomen confirmed a gallbladder polyp and a laparoscopic cholecystectomy was subsequently performed. Histological analysis confirmed primary gallbladder lymphoma. This case report is the first to present gallbladder lymphoma presenting as a polyp. The authors discuss the incidence, presentation and management of gallbladder lymphoma.