Prevalence and Risk Factors of Gallbladder Polypoid Lesions in a Healthy Population

Gallbladder polypoid lesions: Current practices and future prospects

ABSTRACT

Gallbladder polypoid lesions (GPLs) refer to any elevated lesion of the mucosal surface of the gallbladder wall, and the prevalence is estimated to be between 0.9% and 12.1%. GPLs include benign polyps and malignant polyps. Benign polyps are further classified as non-neoplastic polyps and neoplastic polyps. Cholesterol polyps are the most common benign polyps and adenocarcinoma is the main type of malignant polyp. Hepatitis B virus infection, liver function abnormalities, dyslipidemia, and obesity are the main risk factors for GPLs. Studies of biological mechanisms have focused on malignant gallbladder polyps, the development of which is regulated by hormone levels in vivo , gut microbiota, inflammation, oxidative stress, Salmonella typhimurium , and related molecules. Diagnostic modalities include chemical examination and imaging examination, with imaging examination currently being the mainstay. Treatment of patients with GPLs is based on the presence or absence of symptoms, age, size of the polyps, tendency of the polyp to increase, and risk factors for symptomatic malignancy to determine whether surgery should be performed.

Prediction of neoplastic gallbladder polyps in patients with different age level based on preoperative ultrasound: a multi-center retrospective real-world study

BACKGROUND

The prevalence of neoplastic polyps in gallbladder polyps (GPs) increases sharply with age and is associated with gallbladder carcinoma (GBC). This study aims to predict neoplastic polyps and provide appropriate treatment strategies based on preoperative ultrasound features in patients with different age level.

METHODS

According to the age classification of WHO, 1523 patients with GPs who underwent cholecystectomy from January 2015 to December 2019 at 11 tertiary hospitals in China were divided into young adults group (n=622), middle-aged group (n=665) and elderly group (n=236). Linear scoring models were established based on independent risk variables screened by the Logistic regression model in different age groups. The area under ROC (AUC) to evaluate the predictive ability of linear scoring models, long- and short- diameter of GPs.

RESULTS

Independent risk factors for neoplastic polyps included the number of polyps, polyp size (long diameter), and fundus in the young adults and elderly groups, while the number of polyps, polyp size (long diameter), and polyp size (short diameter) in the middle-aged groups. In different age groups, the AUCs of its linear scoring model were higher than the AUCs of the long- and short- diameter of GPs for differentiating neoplastic and non-neoplastic polyps (all P<0.05), and Hosmer-Lemeshow goodness of fit test showed that the prediction accuracy of the linear scoring models was higher than the long- and short- diameter of GPs (all P>0.05).

CONCLUSION

The linear scoring models of the young adults, middle-aged and elderly groups can effectively distinguish neoplastic polyps from non-neoplastic polyps based on preoperative ultrasound features.

Retrospective Study of the Prevalence and Associated Factors of Gallbladder Polyps among Residents of Two Korean Cities

Background/Aims: Well-known risk factors for gallbladder polyps include metabolic syndrome, age, and dyslipidemia. Jeju Island is approximately 80 km from the Korean peninsula and is divided into two administrative regions (Jeju City and Seogwipo City), with Mount Halla intervening in the center. Jeju City has higher employment and birth rates than Seogwipo City. Age and alcohol consumption differ between the two regions, and these factors may affect the prevalence of gallbladder polyps (GBPs). Therefore, we investigated the prevalence of GBPs and compared various factors, including alcohol consumption habits and age, associated with GBPs among residents in the two regions. Methods: This study included 21,734 residents who visited the Health Screening and Promotion Center of Jeju National University Hospital between January 2009 and December 2019. We investigated the prevalence and associated factors of GBPs among residents of Jeju City and Seogwipo City. Results: The prevalence of GBPs in Jeju City and Seogwipo City was 9.8% and 8.9% (p = 0.043), respectively. The mean age and rate of high-risk alcohol intake were higher in Seogwipo City. The mean body mass index and levels of fasting blood glucose, total cholesterol, low-density lipoprotein cholesterol, aspartate aminotransferase, gamma-glutamyl transferase, and alkaline phosphatase were lower in Jeju City. Conclusions: This study demonstrated a significant difference in GBP prevalence between the two regions of Jeju Island. Age and alcohol consumption might contribute to this difference; however, further prospective cohort studies are warranted to confirm our findings.

Impact of nonalcoholic fatty liver disease on the risk of gallbladder polyps in lean and non-obese individuals: A cohort study

BACKGROUND

The association between non-obese or lean nonalcoholic fatty liver disease (NAFLD) and gallbladder polyps (GBPs) has not yet been evaluated. We aimed to determine whether NAFLD is an independent risk factor for the development of GBPs, even in non-obese and lean individuals.

METHODS

We analyzed a cohort of 331 208 asymptomatic adults who underwent abdominal ultrasonography (US). The risk of GBP development was evaluated according to the obesity and NAFLD status.

RESULTS

The overall prevalence of NAFLD and GBPs ≥ 5 mm was 28.5% and 2.9%, respectively. The prevalence of NAFLD among 160 276 lean, 77 676 overweight and 93 256 obese participants was 8.2%, 31.2%, and 61.1%, respectively. Individuals with NAFLD had a significantly higher incidence of GBPs with a size of ≥ 5 mm [adjusted odds ratio (OR) = 1.18; 95% confidence interval (CI): 1.11-1.25]. A higher body mass index and its categories were also significantly associated with an increased risk of GBPs ≥ 5 mm. Moreover, risk of GBPs ≥ 5 mm was significantly increased even in NAFLD individuals who are not obese (lean: adjusted OR = 1.36, 95% CI: 1.19-1.54; overweight: adjusted OR = 1.14, 95% CI: 1.03-1.26, respectively).

CONCLUSIONS

Non-obese/lean NAFLD is an independent risk factor for GBP development, suggesting that NAFLD may play an important role in the pathogenesis of GBPs regardless of the obesity status. Therefore, a more thorough evaluation for GBPs may be necessary when hepatic steatosis is detected on abdominal US, even in non-obese or lean individuals.

Impact of hepatitis B virus infection on the risk of gallbladder polyps: a cohort study

BACKGROUND/AIMS

We aimed to determine whether hepatitis B virus (HBV) or hepatitis C virus (HCV) infection remains an important risk factor for gallbladder polyps (GBPs) in the current context of reduced prevalence of these infections.

METHODS

The cohort included 392,913 asymptomatic adults who underwent abdominal ultrasonography (US).

RESULTS

The prevalence of GBP sized ≥ 5 mm, ≥ 10 mm, and overall (< 5, 5-9 and ≥ 10 mm) was 2.9%, 0.1%, and 12.8%, respectively. The prevalence of hepatitis B surface antigen (HBsAg), hepatitis B core antibody (HBcAb), and hepatitis C antibody (anti-HCV) positivity was 3.2%, 26.7%, and 0.1%, respectively. The GBP risk was significantly increased in HBsAg-positive individuals, with an adjusted odds ratio of 1.66 (95% confidence interval, 1.49-1.85) for GBP ≥ 5 mm, 2.39 (1.53-3.75) for GBP ≥ 10 mm, and 1.49 (1.41-1.59) for overall, whereas there was no significant association between anti-HCV positivity and GBP risk. The GBP risk did not increase significantly in individuals who tested negative for HBsAg but positive for HBcAb.

CONCLUSION

The presence of HBsAg may be an independent risk factor for GBP development in the current context of a indecreasing prevalence of HBsAg positivity. A more comprehensive evaluation of GBP during abdominal US surveillance of HBsAg-positive individuals may be necessary.

Differences in the Impact of Obesity and Metabolic Unhealthiness on the Risk of Gallbladder Polyp

PURPOSE

Differences in the impact of obesity and metabolic health status on the risk of gallbladder polyp (GBP) remain uncertain. Herein, we aimed to compare the risk of GBP ≥5 mm among individuals with different phenotypes based on obesity and metabolic health status.

MATERIALS AND METHODS

A cohort of 253485 asymptomatic adults who underwent abdominal ultrasonography screening were categorized into the following four groups according to obesity and metabolic health status: 1) metabolically healthy non-obese (MHNO), 2) metabolically unhealthy and non-obese (MUNO), 3) metabolically healthy but obese (MHO), and 4) metabolically unhealthy obese (MUO).

RESULTS

The prevalences of GBP ≥5 mm were 2.4%, 3.1%, 3.7%, and 4.0% in the MHNO, MUNO, MHO, and MUO groups, respectively. The multivariable-adjusted odds ratio (OR) values for prevalence of GBP ≥5 mm by comparing the MUNO, MHO, and MUO with the MHNO group were 1.11 [95% confidence interval (CI), 1.04-1.19], 1.30 (95% CI, 1.15-1.47), and 1.37 (95% CI, 1.28-1.45), respectively. The risk of GBP ≥5 mm in the MHO group was significantly higher than that in the MUNO group, but not significantly different from that in the MUO group.

CONCLUSION

Obesity and metabolic unhealthiness appear to be independent risk factors for the prevalence of GBP, and the impact of obesity is greater than that of metabolic unhealthiness, suggesting that maintaining both normal weight and metabolic health may help reduce the risk of GBP.

A Bayesian network model to predict neoplastic risk for patients with gallbladder polyps larger than 10 mm based on preoperative ultrasound features

BACKGROUND

Polyp size of 10 mm is insufficient to discriminate neoplastic and non-neoplastic risk in patients with gallbladder polyps (GPs). The aim of the study is to develop a Bayesian network (BN) prediction model to identify neoplastic polyps and create more precise criteria for surgical indications in patients with GPs lager than 10 mm based on preoperative ultrasound features.

METHODS

A BN prediction model was established and validated based on the independent risk variables using data from 759 patients with GPs who underwent cholecystectomy from January 2015 to August 2022 at 11 tertiary hospitals in China. The area under receiver operating characteristic curves (AUCs) were used to evaluate the predictive ability of the BN model and current guidelines, and Delong test was used to compare the AUCs.

RESULTS

The mean values of polyp cross-sectional area (CSA), long, and short diameter of neoplastic polyps were higher than those of non-neoplastic polyps (P < 0.0001). Independent neoplastic risk factors for GPs included single polyp, polyp CSA ≥ 85 mm ², fundus with broad base, and medium echogenicity. The accuracy of the BN model established based on the above independent variables was 81.88% and 82.35% in the training and testing sets, respectively. Delong test also showed that the AUCs of the BN model was better than that of JSHBPS, ESGAR, US-reported, and CCBS in training and testing sets, respectively (P < 0.05).

CONCLUSION

A Bayesian network model was accurate and practical for predicting neoplastic risk in patients with gallbladder polyps larger than 10 mm based on preoperative ultrasound features.

The value of CT findings combined with inflammatory indicators for preoperative differentiation of benign and malignant gallbladder polypoid lesions

BACKGROUND

The study aimed to explore the value of CT findings and inflammatory indicators in differentiating benign and malignant gallbladder polypoid lesions before surgery.

METHODS

The study comprised a total of 113 pathologically confirmed gallbladder polypoid lesions with a maximum diameter ≥ 1 cm (68 benign and 45 malignant), all of which were enhanced CT-scanned within 1 month before surgery. The CT findings and inflammatory indicators of the patients were analyzed by univariate and multivariate logistic regression analysis to identify independent predictors of gallbladder polypoid lesions, and then a nomogram distinguishing benign and malignant gallbladder polypoid lesions was developed by combining these characteristics. The receiver operating characteristic (ROC) curve and decision curve were plotted to assess the performance of the nomogram.

RESULTS

Base status of the lesion (p < 0.001), plain CT value (p < 0.001), neutrophil-lymphocyte ratio (NLR) (p = 0.041), and monocyte-lymphocyte ratio (MLR) (p = 0.022) were independent predictors of malignant polypoid lesions of the gallbladder. The nomogram model established by incorporating the above factors had good performance in differentiating and predicting benign and malignant gallbladder polypoid lesions (AUC = 0.964), with sensitivity and specificity of 82.4% and 97.8%, respectively. The DCA demonstrated the important clinical utility of our nomogram.

CONCLUSION

CT findings combined with inflammatory indicators can effectively differentiate benign and malignant gallbladder polypoid lesions before surgery, which is valuable for clinical decision-making.

Small Intestinal Bacterial Overgrowth in Patients with Gallbladder Polyps: A Cross-Sectional Study

Purpose

There is probably a high prevalence of small intestinal bacterial overgrowth (SIBO) in patients with gallbladder polyps (GBPs). To date, no study has evaluated the occurrence of SIBO in patients with GBPs. The aim of this study was to investigate the prevalence of SIBO in patients with GBPs and explore the possible association between these two conditions.

Patients and Methods

The hydrogen-methane breath test was used to diagnose SIBO, and patients were divided into GBPs and control groups based on whether GBPs were found under ultrasound. Clinical and paraclinical factors were compared between the two groups.

Results

A total of 297 subjects were included in this study. The prevalence of SIBO was significantly higher in the GBPs group than in the control group (50.0% vs.30.8%, p<0.01). Multivariate logistic regression analysis showed that male (OR=2.26, 95% CI=1.12-4.57, p=0.023), SIBO (OR=3.21, 95% CI=1.69-6.11, p<0.001), fatty liver (OR=2.91, 95% CI= 1.50-5.64, p=0.002) and BMI (OR=1.13, 95% CI=1.01-1.26, p=0.035) were independently associated with GBPs. And by subgroup analysis, we found that the association between SIBO and GBPs was stronger in females than in males (p for interaction< 0.001). In addition, SIBO (OR=5.11, 95% CI=1.42-18.36, p=0.012) and fasting glucose (OR=3.04, 95% CI=1.27-7.28, p=0.013) were found to be associated with solitary polyps.

Conclusion

SIBO was highly prevalent in patients with GBPs, and this association seemed to be stronger among females.

A Bayesian network prediction model for gallbladder polyps with malignant potential based on preoperative ultrasound

BACKGROUND

It is important to identify gallbladder polyps (GPs) with malignant potential and avoid unnecessary cholecystectomy by constructing prediction model. The aim of the study is to develop a Bayesian network (BN) prediction model for GPs with malignant potential in a long diameter of 8-15 mm based on preoperative ultrasound.

METHODS

The independent risk factors for GPs with malignant potential were screened by χ² test and Logistic regression model. Prediction model was established and validated using data from 1296 patients with GPs who underwent cholecystectomy from January 2015 to December 2019 at 11 tertiary hospitals in China. A BN model was established based on the independent risk variables.

RESULTS

Independent risk factors for GPs with malignant potential included age, number of polyps, polyp size (long diameter), polyp size (short diameter), and fundus. The BN prediction model identified relationships between polyp size (long diameter) and three other variables [polyp size (short diameter), fundus and number of polyps]. Each variable was assigned scores under different status and the probabilities of GPs with malignant potential were classified as [0-0.2), [0.2-0.5), [0.5-0.8) and [0.8-1] according to the total points of [- 337, - 234], [- 197, - 145], [- 123, - 108], and [- 62,500], respectively. The AUC was 77.38% and 75.13%, and the model accuracy was 75.58% and 80.47% for the BN model in the training set and testing set, respectively.

CONCLUSION

A BN prediction model was accurate and practical for predicting GPs with malignant potential patients in a long diameter of 8-15 mm undergoing cholecystectomy based on preoperative ultrasound.

Combining polyp diameter and polyp-to-bile ratio by dynamic contrast-enhanced CT scanning can improve the diagnostic specificity of gallbladder neoplastic polyps

OBJECTIVE

This study aimed to distinguish between cholesterol and neoplastic gallbladder polyps using dynamic contrast-enhanced CT.

METHODS

The dataset retrospectively comprised 222 cases, including 106 cases of cholesterol polyps and 116 cases of neoplastic polyps (59 adenoma and 57 adenocarcinoma). The perception and Hounsfield units of the polyps and gallbladder bile were assessed by contrast-enhanced CT, and the polyp-to-bile ratio (PBR) was calculated. Receiver operating characteristic (ROC) curves and area under the curve analyses were used to assess the diagnostic value of the diameter and PBR for neoplastic polyps.

RESULTS

The diameter of cholesterol polyps was significantly smaller than that of neoplastic polyps. The proportion of perceived cholesterol polyps in the plain and arterial phases of CT were significantly lower than those of neoplastic polyps (p < .001). On the contrary, the CT values of gallbladder bile of cholesterol polyps were always significantly higher than those of neoplastic polyps (p < .001). The median PBR values of cholesterol polyps were significantly lower than those of neoplastic polyps (p ≤ .001). ROC analysis showed that diameter and a plain phase PRB had better diagnostic value for neoplastic polyps. Polyp diameter ≥ 11.95 mm and the plain phase PBR ≥1.48 were the optimal cut-off values for diagnosis of neoplastic polyps. Combining a diameter ≥ 12 mm and a PBR in the plain phase ≥1.48 further improved neoplastic polyp diagnostic specificity and positive likelihood ratio (10.453).

CONCLUSIONS

Polyp-to-bile ratio in contrast-enhanced CT scanning is a new and convenient index for identifying cholesterol and neoplastic gallbladder polyps.

Risk factors for gallbladder polyps observed through second-look abdominal sonography in patients with fatty liver disease

FLD, older age group, and alcohol consumption are major risk factors of GBP formation in Taiwanese population. The presence of GBPs might be revealed in second-look examinations of abdominal sonographies.

Development and Validation of a Preoperative Nomogram for Predicting Benign and Malignant Gallbladder Polypoid Lesions

Purpose

The purpose of this study was to develop and validate a preoperative nomogram of differentiating benign and malignant gallbladder polypoid lesions (GPs) combining clinical and radiomics features.

Methods

The clinical and imaging data of 195 GPs patients which were confirmed by pathology from April 2014 to May 2021 were reviewed. All patients were randomly divided into the training and testing cohorts. Radiomics features based on 3 sequences of contrast-enhanced computed tomography were extracted by the Pyradiomics package in python, and the nomogram further combined with clinical parameters was established by multiple logistic regression. The performance of the nomogram was evaluated by discrimination and calibration.

Results

Among 195 GPs patients, 132 patients were pathologically benign, and 63 patients were malignant. To differentiate benign and malignant GPs, the combined model achieved an area under the curve (AUC) of 0.950 as compared to the radiomics model and clinical model with AUC of 0.929 and 0.925 in the training cohort, respectively. Further validation showed that the combined model contributes to better sensitivity and specificity in the training and testing cohorts by the same cutoff value, although the clinical model had an AUC of 0.943, which was higher than 0.942 of the combined model in the testing cohort.

Conclusion

This study develops a nomogram based on the clinical and radiomics features for the highly effective differentiation and prediction of benign and malignant GPs before surgery.

Cáncer de vesícula biliar, una visión actual

Introducción. El diagnóstico de cáncer de vesícula biliar se realiza generalmente de forma incidental durante el estudio de las piezas quirúrgicas o cuando la enfermedad está avanzada y se expresa por su diseminación. Muy pocas veces se diagnostica de forma preoperatoria. Corresponde a la neoplasia más común de las vías biliares y su incidencia varía de acuerdo a la región geográfica. La región andina en Latinoamérica presenta una de las mayores incidencias a nivel mundial. Métodos. Se realizó una revisión narrativa de la literatura, para presentar una información actualizada en lo referente a los factores de riesgo (incluyendo las alteraciones genéticas y moleculares), al diagnóstico y al tratamiento de esta patología. Basados en los datos actuales, presentamos algunas recomendaciones dirigidas al diagnóstico temprano, que permita un manejo más adecuado de nuestros pacientes. Resultados. Se han implicado nuevos factores de riesgo relacionados con la etiología del cáncer de vesícula biliar, como la obesidad, factores genéticos y moleculares. A pesar de la disponibilidad de los métodos diagnósticos imagenológicos, no ha ocurrido una importante variación porcentual en cuanto al estadio al momento del diagnóstico. Conclusiones. El manejo quirúrgico del cáncer de vesícula biliar está indicado en los estadios más tempranos de la enfermedad y es importante evaluar las opciones terapéuticas en pacientes con enfermedad avanzada. Se considera de suma importancia el estudio anatomopatológico de la pieza quirúrgica y la revisión del informe por parte del cirujano

Prevalence and risk factors of gallbladder polyps in primary health care centers among patients examined by abdominal ultrasonography in Qatar: a case-control study

BACKGROUND

Gallbladder (GB) polyps are raised lesions from the GB wall and projected into its lumen. The prevalence of GB polyps ranged between 4.3% and 12.3%. The clinical presentation of GB polypoid lesions vary, can be nonspecific and vague, and may be asymptomatic. Identifying malignant and premalignant polyps is important to provide treatment early and prevent cancer spread or development of malignancy. Ultrasonography (US) is the first imaging modality widely used in abdominal imaging. It is a noninvasive, rapid, painless, and safe imaging technique, with no radiation; thus, it is considered the best available examination with good sensitivity and specificity for GB polyps.

AIM OF THE WORK

This study aimed to determine the relative frequency of the GB polyps and its risk factors among patients who underwent abdominal US in Primary Health Care Corporation, Qatar.

MATERIALS AND METHODS

This was quantitative multicenter observational case-control study nested in a cross-sectional design. For the cross-sectional top-level study, the first step was to assess available abdominal ultrasound studies for the presence of GB polyps and stones. The second step was to perform a case-control study with three groups (a case group and two control groups; first, participants without GB stones and GB polyps; second, patients with GB stones but without GB polyps).

RESULTS

The study evaluated the GB images of 7156 individuals. The overall prevalence of GB polyps was 7.4% in the study population. Specifically, the overall prevalence of solitary GB polyp was 4.2% and that of multiple GB polyps was 3.2%. Regarding the size distribution of GB polyps in positive cases, 89.4% were < 6 mm, 9.3% were 69 mm, and 1.3% were ≥ 10 mm. Prevalence rate of selected comorbidities were as follows: liver disease, 1.8%; diabetes mellitus, 25.5%; hypertension, 25.5%; and dyslipidemia, 29.8%. The prevalence in male and female patients was 7.7% and 7%, respectively. The prevalence of GB polyps was higher in south-eastern patients (21.4% of positive cases) and was the highest in the overweight group (8.8%). A higher prevalence was noted in the hypertensive group (hypertensive group, 9.8%; non-hypertensive group, 6.6%) and dyslipidemia group (dyslipidemia group, 7.8%; no dyslipidemia group, 7.2%). Moreover, a higher prevalence was noted in hepatitis B surface (HBS)-positive group (15%) than in the HBS-negative group (8.2%) and slightly higher in Helicobacter pylori antigen positive group than in the negative group.

CONCLUSION

Abdominal US is an important and commonly used imaging modality in the detection of GB polyps. In this study, the prevalence of GB polyps was approximately 7.4%, with higher prevalence in participants who were overweight and had diabetes mellitus, hypertension, and dyslipidemia.

Triphasic dynamic enhanced computed tomography for differentiating cholesterol and adenomatous gallbladder polyps

BACKGROUND

Triphasic dynamic enhanced computed tomography (CT) scans were acquired to identify cholesterol and adenomatous gallbladder (GB) polyps that were inaccurately diagnosed before surgery.

PURPOSE

To evaluate the CT findings of 1.0- to 2.0-cm GB polyps for differentiating between cholesterol and adenomatous polyps.

METHODS

Fifty-two patients with GB polyps were treated surgically from December 2017 to July 2020 and were retrospectively divided into 2 groups according to the postoperative pathologic results: a cholesterol group with 30 patients and an adenomatous group with 22 patients. Unenhanced and triphasic dynamic enhanced CT scans were performed for all the patients within 2 weeks before surgery. The CT image parameters were measured and analyzed by 2 senior radiologists blinded to the pathological diagnoses.

RESULTS

Of the 22 patients in the adenomatous group, 77.3% were female and 22.7% were male, with a mean age of 53.5 years; among the 30 patients in the cholesterol group, 66.7% were female and 33.3% were male, with a median age of 50.1 years. The CT image parameters of all 52 patients with GB polyps were analyzed. Significant differences were found in the arterial phase CT values, portal venous phase CT values, delayed phase CT values, ∆CT1 values (portal venous phase CT minus delayed phase CT values), and ∆CT2 values (arterial phase CT minus delayed phase CT values) between the cholesterol and adenomatous polyp groups (p < 0.05). In differentiating the two groups, the ∆CT1 and ∆CT2 values were superior to the arterial, portal venous and delayed phase CT values regarding both sensitivity and specificity.

CONCLUSION

The arterial phase CT values, portal venous phase CT values, delayed phase CT values, and ∆CT values (including ∆CT1 and ∆CT2) from triphasic dynamic enhanced CT scans can differentiate the nature of gallbladder polypoid lesions, with the ∆CT values having the highest sensitivity and specificity.

Are there modifiable risk factors affecting the prevalence of gallbladder polyps or those 5 mm or larger? A retrospective cross-sectional study

Gallbladder polyps (GBPs), especially GBPs ≥5 mm in diameter, are clinically important because they can progress to gallbladder cancer. The known modifiable risk factors for GBP are obesity, metabolic syndrome, and dyslipidemia; however, there is limited evidence regarding specific modifiable risk factors for GBPs ≥5 mm in diameter. Therefore, this study is aimed to investigate the existence of modifiable risk factors affecting the prevalence of GBPs and GBPs ≥5 mm in diameter in a Korean population.A total of 10,119 subjects who visited a single health-screening center at Jeju National University Hospital between January 2009 and December 2019 was included in this study. Binary logistic analyses were performed to identify risk factors affecting the prevalence of GBPs and GBPs ≥5 mm in diameter.The overall prevalence of GBPs and GBPs ≥5 mm in diameter were 9.0% and 4.1%, respectively. Multivariable analysis identified male gender as an independent risk factor affecting the prevalence of GBPs. Moreover, multivariable analysis revealed age and high-density lipoprotein cholesterol levels as independent risk factors for GBPs ≥5 mm in diameter.This study showed that gender was a risk factor affecting the prevalence of GBPs and that age and high-density lipoprotein-cholesterol levels were risk factors for the presence of GBPs ≥5 mm in diameter. High-density lipoprotein cholesterol levels could be a modifiable risk factor affecting the prevalence of large-diameter GBPs.

Value of high frame rate contrast-enhanced ultrasound in distinguishing gallbladder adenoma from cholesterol polyp lesion

OBJECTIVES

To compare the diagnostic value of high frame rate contrast-enhanced ultrasound (H-CEUS) in distinguishing gallbladder adenomas from cholesterol polyp lesions with that of CEUS.

METHODS

This study enrolled 94 patients with gallbladder polyp lesions (GPLs) who underwent laparoscopic cholecystectomy. CEUS and H-CEUS were performed before surgery. The perfusion features of GPLs and the final diagnosis as determined by both technologies were compared.

RESULTS

There were differences in vascular types between gallbladder adenomas and cholesterol polyp lesions observed on H-CEUS (p < 0.05), while there were no differences in vascular types between gallbladder adenomas and cholesterol polyp lesions observed on CEUS (p > 0.05). In the cholesterol polyp lesion group, there were no differences in vascular types between CEUS and H-CEUS (p > 0.05), while the vascular types were different between CEUS and H-CEUS in the gallbladder adenoma group (p < 0.05). The diagnostic value of H-CEUS in distinguishing gallbladder adenomas from cholesterol polyp lesions was better than that of CEUS.

CONCLUSIONS

H-CEUS improved the time resolution by increasing the frame rate, which helped to accurately reflect the difference in the microcirculation of GPLs and improved the ability of a differential diagnosis between cholesterol polyp lesions and adenomas. H-CUES may provide an effective means of imaging for patients with GPLs regarding the choice of treatment options.

KEY POINTS

• High frame rate CEUS improves the time resolution of CEUS by increasing the frame rate. • High frame rate CEUS is helpful to accurately evaluate the microvascular morphology of a gallbladder polyp lesion in the arterial phase. • High frame rate CEUS helps patients with gallbladder polyp lesions to choose the appropriate treatment means.

Establishment of a nomogram prediction model for long diameter 10-15 mm gallbladder polyps with malignant tendency

BACKGROUND

Surgical indications for the treatment of gallbladder polyps are controversial. Evaluation of gallbladder polyps with malignant tendency and indications for cholecystectomy in patients with long diameter polyps of 10 to 15 mm require further analysis and discussion. In this study, our objective was to re-evaluate indications for the surgical resection of gallbladder polyps and construct a nomogram model for the prediction of gallbladder polyps with malignant tendency.

METHODS

Clinicopathologic data of 2,272 patients who had undergone cholecystectomy for gallbladder polyps were collected from 11 medical centers in China. Risk factor analyses and nomogram prediction model for gallbladder polyps with malignant tendency were conducted.

RESULTS

Excluding 311 patients with cholelithiasis and 488 patients with long diameter polyps ≤5 and >15 mm, factors that differed significantly among patients with gallbladder polyps having a long diameter of 6 to 9 mm (885 cases) and 10 to 15 mm (588 cases) were polyp detection time, CEA and CA19-9 levels, number of polyps, fundus, echogenicity, gallbladder wall thickness and postoperative pathologic features (P < .05). Among 588 patients with gallbladder polyps with a long diameter of 10 of 15 mm, multivariate analysis indicated the following independent risk factors of gallbladder polyps with malignant tendency: single polyps (OR = 0.286/P < .001), polyps with broad base (OR = 2.644/P = .001), polyps with medium/low echogenicity (OR = 2.387/P = .003), and polyps with short diameter of 7 to 9 or 10 to 15 mm (OR = 3.820/P = .005; OR = 2.220/P = .048, respectively). The C-index of the nomogram model and internal validation were .778 and .768, respectively. In addition, a sample online calculator for the nomogram prediction model had been created (https://docliqi.shinyapps.io/dynnom/).

CONCLUSION

Indications for cholecystectomy in patients with gallbladder polyps with a long diameter of 10 to 15 mm should be assessed by combining the information on short diameter, number of polyps, fundus, and echogenicity. The nomogram model can be used to predict the risk for the development of gallbladder polyps with malignant tendency.

Dual-energy CT to differentiate gallbladder polyps: cholesterol versus adenomatous

BACKGROUND

Dual-energy computed tomography (DE-CT) scans were acquired to identify cholesterol and adenomatous gallbladder (GB) polyps, which have not been well evaluated before surgery.

PURPOSE

To evaluate the DE-CT findings of GB polyps 1.0-2.0 cm in size and differentiate between cholesterol and adenomatous polyps.

MATERIAL AND METHODS

Forty-six patients with GB polyps were surgically treated from December 2017 to December 2019 and divided into two groups according to their postoperative pathologic results: a cholesterol group with 26 patients and an adenomatous group with 20 patients. All of these patients underwent DE-CT imaging with tube voltages of 80 kVp and 140 kVp within two weeks before surgery. Mean attenuation values were measured for every GB polyp at 80/140 kVp and at 40/140 keV. The mean attenuation value changes between 140 kVp and 80 kVp (MAVC_{140-80 kVp}) and mean attenuation value changes between 100 keV and 40 keV (MAVC_{100-40 keV}) were calculated.

RESULTS

The CT image parameters of all 46 patients with GB polyps were analyzed. There were significant differences in MAVC_{140-80 kVp} and MAVC_{100-40 keV} between cholesterol and adenomatous polyps (P <0.05); these values were positive for cholesterol polyps and negative for adenomatous polyps.

CONCLUSION

The unique energy spectrum information provided by DE-CT scans is helpful in differentiating between cholesterol and adenomatous polyps 1.0-2.0 cm in size.

[Gallbladder polyps: modern approaches to diagnostics and treatment]

Gallbladder polyps are an elevation of the mucous membrane that protrudes into the lumen of the gallbladder cavity. Their prevalence in the general population varies from 0.3 to 13.8%. According to the modern classification, polyps of the gallbladder are divided into benign non-tumor, benign tumor and malignant tumor polyps. A review of modern literature presents cohort and randomized controlled trials, including those summarized in meta-analyzes and systematic reviews, suggesting that the dominant form of polypoid formations of the gallbladder are cholesterol pseudo-polyps with no malignant potential associated with impaired cholesterol metabolism, often combined with gallbladder cholesterosis, metabolic syndrome and cardiovascular morbidity. Evidence is building up on the effectiveness of ursodeoxycholic acid for controlling components of the metabolic syndrome and cardiovascular risks. Ursodeoxycholic acid preparations may become promising for the management of cholesterol polyps.

Gallbladder polyps: evolving approach to the diagnosis and management

Gallbladder (GB) polyp is a mucosal projection into the GB lumen. With increasing health awareness, GB polyps are frequently found using ultrasonography during health screening. The prevalence of GB polyps ranges between 1.3% and 9.5%. Most patients are asymptomatic and have benign characteristics. Of the nonneoplastic polyps, cholesterol polyps are most common, accounting for 60%-70% of lesions. However, a few polyps have malignant potential. Currently, the guidelines recommend laparoscopic cholecystectomy for polyps larger than 1 cm in diameter due to their malignan potential. The treatment algorithm can be influenced by the size, shape, and numbers of polyps, old age (>50 years), the presence of primary sclerosing cholangitis, and gallstones. This review summarizes the commonly recognized concepts on GB polyps from diagnosis to an algorithm of treatment.

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.

The management of gallbladder polyps

Neoplastic gallbladder polyps (NGP) are rare; the prevalence in the overall population is less than 10%. NGP are associated with a risk of malignant degeneration and must be distinguished from other benign gallbladder polypoid lesions that occur more frequently. NGP are adenomas and the main risk associated with their management is to fail to detect their progression to gallbladder cancer, which is associated with a particular poor prognosis. The conclusions of the recent European recommendations have a low level of evidence, based essentially on retrospective small-volume studies. Abdominal sonography is the first line study for diagnosis and follow-up for NGP. To prevent the onset of gallbladder cancer, or treat malignant degeneration in its early phases, all NGP larger than 10mm, or symptomatic, or larger than 6mm with associated risk factors for cancer (age over 50, sessile polyp, Indian ethnicity, or patient with primary sclerosing cholangitis) are indications for cholecystectomy. Apart from these situations, simple sonographic surveillance is recommended for at least five years; if the NGP increases in size by more than 2mm in size, cholecystectomy is indicated. Laparoscopic cholecystectomy is possible but if the surgeon feels that the risk of intra-operative gallbladder perforation is high, conversion to laparotomy should be preferred to avoid potential intra-abdominal tumoral dissemination. When malignant NGP is suspected (size greater than 15mm, signs of locoregional extension on imaging), a comprehensive imaging workup should be performed to search for liver extension: in this setting, radical surgery should be considered.

Computer-aided diagnosis of gallbladder polyps based on high resolution ultrasonography

BACKGROUND AND OBJECTIVE

Gallbladder polyp is a common disease with an overall population prevalence between 4 and 7%. It can be classified as neoplastic and non-neoplastic lesions. Surgical treatment is necessary for neoplastic polyps. Due to its easy accessibility and nonradioactive, ultrasonography is the mostly used preoperative diagnosis tool for gallbladder polyps. However, human image analysis depends greatly on levels of experience, which results in many overtreatment cases and undertreatment cases in clinics.

METHODS

In this study, we proposed an ultrasound image segmentation algorithm, combined with principal components analysis (PCA) and AdaBoost algorithms to construct a computer-aided diagnosis system for the differentiate diagnosis of neoplastic and non-neoplastic gallbladder polyps.

RESULTS

The proposed segmentation method achieved a high accuracy of 95% for outlining the gallbladder region. The accuracy, sensitivity, specificity for the proposed computer-aided diagnosis system based on the segmented images are 87.54%, 86.52% and 89.40%, compared to 69.05%, 67.86% and 70.17% with convolutional neural network. The diagnosis result is also slightly higher than the human eyes of sonologists (86.22%, 85.19% and 89.18% as an average of four sonologists), while with a much faster diagnosis speed (0.02s vs 3s).

CONCLUSIONS

We proposed an efficient ultrasound image segmentation approach and a reliable system of automatic diagonals of neoplastic and non-neoplastic gallbladder polyps. The results show that the diagnosis accuracy is competitive to the expert sonologists while requires much less diagnosis time.

Gallbladder Polyps: Rare Lesions in Childhood

OBJECTIVE

Unlike adults, gallbladder polyps (GPs) are rare in childhood. The aim of this study was to evaluate patients with a GP diagnosis.

METHODS

Patients who were diagnosed with GP via ultrasonography from October 2012 to October 2017 were retrospectively evaluated in terms of sociodemographic characteristics and laboratory findings.

RESULTS

The study included 19 patients diagnosed with GP and followed up in our department. The patients comprised 14 (73.6%) girls with a mean age of 13.9 ± 4.1 years and a mean follow-up period of 10.2 ± 5.4 months (range, 3-26 months). The most common presenting symptom of the patients (n = 15, 78.9%) for ultrasonography was abdominal pain without biliary symptoms. Location of the polyps was in the corpus in 55% of patients, and either in the fundus (20%) or the neck of the gallbladder (25%). The average diameter of the polyps was 4.5 ± 1.6 mm (range, 2-9 mm). Multiple polyps were observed in 3 patients. No significant change in the number or size of polyps was noted at the end of the follow-up periods. Cholecystectomy was applied to 1 patient who had >5 polyps with a rapid increase in size, and the pathology report was hamartomatous polyp. There was no remarkable change in the clinical or laboratory findings of other patients during the follow-up period.

CONCLUSION

In this study, GPs could be seen in young children as young as 16 months of age and ultrasonography is sufficient for follow-up in stable and asymptomatic patients.

Risk factors of gallbladder polyps formation in East Asian population: A meta-analysis and systematic review

To perform Meta-analysis to identify risk factors associated with gallbladder polyps (GBP) formation in east Asian population. Three English electronic bibliographic databases includes PubMed, Embase and Medline, with reviewed researches from 1986 to 2017. All possible risk factors of GBP formation were recorded. Meta-analyses were performed by Review Manager Software. Pooled odds ratios (OR) or the mean difference (MD) were used to determine risk factors. Sixteen studies and 227021 people were recruited, including 17261 people with GBP and 209760 without GBP. For categorical variables evaluated by OR test., risk factors of GBP formation were male gender (OR, 1.63; 95%CI, 1.42-1.87) and positive HBsAg. GBP formation were not correlated with age <50 years old, hypertension, DM, BMI ≥ 25kg/m², smoking, drinking, HDL decrease, TC increase, TG increase, fatty liver and GBS. For continuous variables evaluated by MD test, risk factors of GBP formation were DBP (MD, 1.08; 95%CI, 0.15-2.02), mean BMI (MD,0.19; 95%CI,0.02-0.35), waist circumference (MD,1.780; 95%CI, 0.17,3.40), mean LDL (MD,0.89; 95%CI,0.03-1.75), mean HDL (MD,-1.87; 95%CI,-3.21 to -0.52). GBP formation were not correlated with mean age, SBP, mean TC, mean TG, ASL and ALT. In conclusion, risk factors of gallbladder polyp formation included male gender, higher BMI, higher waist circumference, higher DBP, higher LDL, lower HDL and positive HBsAg in east Asian population. GBP formation was not correlated with age, hypertension, DM, smoking, drinking, fatty liver, GBS, TC, TG, SBP, ASL and ALT. The mechanism of Dyslipidemias causing GBP needs deeper study in future.

Gallbladder polyps - a follow-up study after 11 years

Background

The aim of our study was to investigate the prevalence and natural long-term progression of gallbladder polyps in a random sample of the general population.

Methods

Four hundred and thirteen subjects (190 women, 223 men; aged 29–75 years) were studied first in 2002 and again eleven years later in 2013. All subjects were interviewed using a standardised questionnaire, anthropometric data were recorded, and an abdominal ultrasound scan was carried out.

Results

The prevalence of gallbladder polyps was 6.1% (115/1880) in the 2002 study and 12.1% (50/413) in the 2013 follow-up study. After eleven years, 36 subjects (8.7%, 36/413) had developed new polyps, thirteen subjects (48.1%, 13/27) no longer had gallbladder polyps, and 14 subjects (51.9%, 14/27) still had polyps. The number of polyps had increased in six of these subjects (43%, 6/14), decreased in a further six (43%, 6/14), and remained unchanged in two (14%, 2/14). The mean polyp size was 4.7 mm (± 2.2 mm, range 2–20 mm) in 2002 and 4.0 mm (± 1.9 mm, range 0.5–11 mm) at follow-up. A decrease in polyp size was noted in seven (50%) of the 14 subjects, an increase in size in five subjects (35.7%), and no change in two subjects (14.3%). The shape of the polyps had changed from pedunculated to sessile in two subjects (14.3%, 2/14) and from sessile to pedunculated in one subject (7.1%, 1/14).

Conclusions

In long-term follow-up, the prevalence of gallbladder polyps increased, with new lesions developing in 8.7% of the population. Polyps persisted in 51.9% of the subjects who had them in the original study and disappeared in the other 48.1%.

Correlation of dyslipidemias and gallbladder polyps-A large retrospective study among Chinese population

OBJECTIVE

Aim to explore the association of dyslipidemias with GBP prevalence, number and size in a large Chinese population in Beijing. Dyslipidemias include hypercholesterolemia, hypertriglyceridemia, increased low density lipoprotein (LDL) and decreased high density lipoproteins (HDL).

METHODS

Prevalence of GBP and its association with dyslipidemias were retrospectively investigated among subjects who underwent check-up at Health Screening Center of Xuanwu Hospital between January 2014 and December 2017.

RESULTS

This study enrolled 97117 participants. Prevalence of GBP was 7.3%. There were significant differences in increased LDL (595/7107 vs 6004/90010, P = 0.000) and increased cholesterol (TC) (403/7107 vs 4846/90010,P = 0.000) between GBP group and control group, but not in decreased HDL and increased triglyceride (TG). Logistic regression analysis showed that gender, age, BMI, SBP, DBP and LDL were independently associated with GBP. People with increases LDL had 1.488 times higher risk for GBP formation. Trend of dyslipidemias prevalence change according to age was similar with that of GBP. Increased LDL group had higher GBP prevalence rate (9.0% vs 7.2%, p = 0.000), multiple GBP proportion (2.9% vs 2.2%, p = 0.000) and large polyps with diameter ≥ 5 mm proportion (3.7% vs 2.6%,p = 0.000). Comparing with control group, there was higher proportion of large polyps in Increased TC group (3.2% vs 2.7%, p = 0.019) and decreased HDL group (3.0% vs 2.6%,p = 0.028). Increased TG group had not difference with its control group in GBP prevalence, number or size.

CONCLUSION

Dyslipidemias is associated with GBP formation. Dyslipidemias change according to age is consistent with GBP prevalence. Increased LDL was a more related risk factor rather than decreased HDL, increased TC or TG.

Ovo-lactovegetarian diet as a possible protective factor against gallbladder polyps in Taiwan: A cross-sectional study

OBJECTIVE

Gallbladder polyps (GBPs) are an increasingly common incidental finding and 3% to 8% of GBPs become malignant. A poor prognosis is expected in patients with gallbladder cancer. No studies have considered the relationship between diet and the development of GBPs in the Taiwanese population. The objective of this study was to investigate whether a vegetarian diet protects against GBP development.

MATERIALS AND METHODS

This cross-sectional study included 11,717 individuals who received a health checkup at Taipei Tzu Chi Hospital (New Taipei City, Taiwan) between October 2011 and October 2016. All individuals completed questionnaires that collected data about their characteristics, dietary patterns, and lifestyle. Physical examinations were conducted, and blood chemistry tests were performed. The presence of GBPs was determined using ultrasonography. We subsequently evaluated the association between diet and GBP prevalence using multivariate analysis.

RESULTS

The prevalence of GBPs for the entire group was 8.3%. GBPs were significantly less common in the vegetarian groups (vegans 9.0%, ovo-lacto vegetarians 7.5%, and semi-vegetarians 7.2%) compared with the omnivore group (9.6%) (P = 0.002). Step-wise logistic regression revealed that an ovo-lacto vegetarian diet was a possible protective factor (odds ratio = 0.83, P = 0.015).

CONCLUSIONS

The study findings showed a strong negative association between an ovo-lacto vegetarian diet and GBP occurrence.

Strategy for discriminating cholesterol and premalignancy in polypoid lesions of the gallbladder: a single-centre, retrospective cohort study

BACKGROUND

The present study aimed to assess the risk factors of cholesterol and premalignancy in polypoid lesions of the gallbladder (PLGs) and to establish an appropriate treatment strategy.

METHODS

Data from patients who underwent cholecystectomy at the First Affiliated Hospital, School of Medicine, Zhejiang University, between January 2011 and July 2017, were collected retrospectively.

RESULTS

A total of 1561 patients were included in the present study. The cohort comprised of 636 (40.7%) males and 925 (59.3%) females, with a mean age of 49.5 (range 16-88) years; 65.6% (1024/1561) demonstrated cholesterol lesions in this cohort, among which cholesterol polyps accounted for 81.0%. Age younger than 50 years and multiple number of polyps were found to be independent predictive variables for cholesterol lesions (odds ratio (OR) 3.461, 95% confidence interval (CI) 2.058-5.820, P < 0.001 and OR 3.321, 95% CI 1.988-5.547, P < 0.001, respectively). The presence of polyp growth was associated with premalignancy (OR 5.366, 95% CI 1.466-19.637, P = 0.011), and the presence of clinical symptoms indicated benign non-cholesterol lesions (OR 0.368, 95% CI 0.153-0.885, P = 0.026).

CONCLUSION

In the case of patients ≥50 years old with single asymptomatic polyp, cholecystectomy was recommended if the polyp presented growth at a rate above 3-4 mm within 6 months. If not, trimonthly ultrasound follow up was recommended, and clinicians should carefully assess the risk factors for premalignancy in PLGs.

Gallbladder Polypoid-Lesions: What Are They and How Should They be Treated? A Single-Center Experience Based on 1446 Cholecystectomy Patients

BACKGROUND AND AIM

Gallbladder polypoid-lesions (GPs) are commonly seen on ultrasonography (USG), but several aspects of this problem are ill-defined. This study aimed to analyze clinic and pathologic characteristics of 1446 USG-detected GPs, identify predictive factors for cholesterol lesions and malignancy, and provide comments and recommendations on specific aspects of GPs.

METHODS

We retrospectively analyzed clinic files of 1446 patients who underwent cholecystectomy for USG-detected GPs between 2008 and 2015 in Gallbladder Diseases Center, East Hospital of Tongji University.

RESULTS

For the 1446 patients, the F: M ratio and the mean age were 1.06: 1 and 45 years, and most of them were asymptotic (80.3%) and had multiple polyps (62.5%). All the 1446 GPs were classified into three categories: cholesterol, benign non-cholesterol, and malignant lesions, with respective proportion of 87.1% (1260), 11.2% (162), and 1.7% (24). Over half of benign non-cholesterol lesions, of which most were premalignant neoplasm (adenoma), were less than 10 mm. Multiple number and the presence of lipid abnormalities were significantly more associated with cholesterol than non-cholesterol lesions, with odd ratios (OR) of 2.9 (P < 0.001) and 1.6 (P = 0.023), respectively. Age ≥50 years, present symptoms, size ≥10 mm and concurrent gallstones were independent predictive factors to discriminate malignant polyps from premalignant lesions, with ORs of 16.5 (P < 0.001), 6.3 (P = 0.013), 41.5 (P = 0.014), and 18.0 (P = 0.002), respectively.

CONCLUSIONS

According to our proposed classification, the vast majority of GPs were cholesterol lesions without malignant potential and associating with metabolic diseases. We strongly recommend that risk factors of GPs be investigated by subtypes, and patients with GPs be treated with personalized and differentiated strategies.

The gallbladder polypoid-lesions conundrum: moving forward with controversy by looking back

Gallbladder polypoid-lesions (GPs) are found in 5-10% of the general population. Although the majority of GPs are asymptomatic and benign in nature, some of them can develop into cancer, which carries a poor prognosis. Currently, the risk factors, natural history and classification of GPs remain unclear, differentiation of benign from malignant or premalignant GPs based on available diagnostic modalities and/or features of patients and GPs remain difficult, and there are still no evidence-based guidelines to dictate when and how GPs of varying sizes and subtypes should be managed. All of these facts have left GPs in uncertainty. Areas covered: A literature search was performed using the terms 'gallbladder polyps' AND 'polypoid lesion of gallbladder' in the PubMed database from January 2000 to September 2016. Original and review articles on almost all aspects of GPs in humans, especially diagnosis, treatment and surveillance, were reviewed and analyzed. Reference lists of reviews and original articles were also examined for relevant publications. Expert commentary: The present article summarizes almost all aspects of GPs, analyzes the controversies, and outlines our data and comments. It is the authors' purpose that this article be beneficial for scientific, accurate and appropriate management of GPs.