Is cholecystectomy a reasonable treatment option for simple gallbladder polyps larger than 10 mm?

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.

Preliminary study on diagnosis of gallbladder neoplastic polyps based on contrast-enhanced ultrasound and grey scale ultrasound radiomics

Objective

Neoplastic gallbladder polyps (GPs), including adenomas and adenocarcinomas, are considered absolute indications for surgery; however, the distinction of neoplastic from non-neoplastic GPs on imaging is often challenging. This study thereby aimed to develop a CEUS radiomics nomogram, and evaluate the role of a combined grey-scale ultrasound and CEUS model for the prediction and diagnosis of neoplastic GPs.

Methods

Patients with GPs of ≥ 1 cm who underwent CEUS between January 2017 and May 2022 were retrospectively enrolled. Grey-scale ultrasound and arterial phase CEUS images of the largest section of the GPs were used for radiomics feature extraction. Features with good reproducibility in terms of intraclass correlation coefficient were selected. Grey-scale ultrasound and CEUS Rad-score models were first constructed using the Mann-Whitney U and LASSO regression test, and were subsequently included in the multivariable logistic regression analysis as independent factors for construction of the combined model.

Results

A total of 229 patients were included in our study. Among them, 118 cholesterol polyps, 68 adenomas, 33 adenocarcinomas, 6 adenomyomatoses, and 4 inflammatory polyps were recorded. A total of 851 features were extracted from each patient. Following screening, 21 and 15 features were retained in the grey-scale and CEUS models, respectively. The combined model demonstrated AUCs of 0.88 (95% CI: 0.83 - 0.93) and 0.84 (95% CI: 0.74 - 0.93) in the training and testing set, respectively. When applied to the whole dataset, the combined model detected 111 of the 128 non-neoplastic GPs, decreasing the resection rate of non-neoplastic GPs to 13.3%.

Conclusion

Our proposed combined model based on grey-scale ultrasound and CEUS radiomics features carries the potential as a non-invasive, radiation-free, and reproducible tool for the prediction and identification of neoplastic GPs. Our model may not only guide the treatment selection for GPs, but may also reduce the surgical burden of such patients.

Risk stratification of gallbladder masses by machine learning-based ultrasound radiomics models: a prospective and multi-institutional study

OBJECTIVE

This study aimed to evaluate the diagnostic performance of machine learning (ML)-based ultrasound (US) radiomics models for risk stratification of gallbladder (GB) masses.

METHODS

We prospectively examined 640 pathologically confirmed GB masses obtained from 640 patients between August 2019 and October 2022 at four institutions. Radiomics features were extracted from grayscale US images and germane features were selected. Subsequently, 11 ML algorithms were separately used with the selected features to construct optimum US radiomics models for risk stratification of the GB masses. Furthermore, we compared the diagnostic performance of these models with the conventional US and contrast-enhanced US (CEUS) models.

RESULTS

The optimal XGBoost-based US radiomics model for discriminating neoplastic from non-neoplastic GB lesions showed higher diagnostic performance in terms of areas under the curves (AUCs) than the conventional US model (0.822-0.853 vs. 0.642-0.706, p < 0.05) and potentially decreased unnecessary cholecystectomy rate in a speculative comparison with performing cholecystectomy for lesions sized over 10 mm (2.7-13.8% vs. 53.6-64.9%, p < 0.05) in the validation and test sets. The AUCs of the XGBoost-based US radiomics model for discriminating carcinomas from benign GB lesions were higher than the conventional US model (0.904-0.979 vs. 0.706-0.766, p < 0.05). The XGBoost-US radiomics model performed better than the CEUS model in discriminating GB carcinomas (AUC: 0.995 vs. 0.902, p = 0.011).

CONCLUSIONS

The proposed ML-based US radiomics models possess the potential capacity for risk stratification of GB masses and may reduce the unnecessary cholecystectomy rate and use of CEUS.

CLINICAL RELEVANCE STATEMENT

The machine learning-based ultrasound radiomics models have potential for risk stratification of gallbladder masses and may potentially reduce unnecessary cholecystectomies.

KEY POINTS

• The XGBoost-based US radiomics models are useful for the risk stratification of GB masses. • The XGBoost-based US radiomics model is superior to the conventional US model for discriminating neoplastic from non-neoplastic GB lesions and may potentially decrease unnecessary cholecystectomy rate for lesions sized over 10 mm in comparison with the current consensus guideline. • The XGBoost-based US radiomics model could overmatch CEUS model in discriminating GB carcinomas from benign GB lesions.

Propensity score matching analysis of perioperative outcomes including quality of life after multi-port vs. single port laparoscopic cholecystectomy: a nationwide prospective multicenter study in Korea

INTRODUCTION

The usefulness of single-port laparoscopic cholecystectomy (SPLC) as compared to multi-port laparoscopic cholecystectomy (MPLC) remains controversial. Between SPLC and MPLC, we compared outcomes, especially subjective aspects, such as quality of life (QoL).

MATERIAL AND METHODS

This multi-center study, involving 20 institutions from 2016 to 2017, enrolled 2507 patients who underwent laparoscopic cholecystectomy. Various perioperative outcomes, pain assessed by the numeric rating scale (NRS) score, and QoL evaluated by the gastrointestinal QoL index (GIQLI) questionnaire, were compared between the two procedures. We generated balanced groups after propensity score matching (PSM) using preoperative factors that influence the decision to perform MPLC or SPLC.

RESULTS

MPLC and SPLC were performed in 2176 and 331 patients, respectively. Nine hundred and twelve and 329 patients, respectively, were selected from the two groups by PSM. Operation time was longer and surgical difficulty was lower in SPLC. There were no significant differences in most outcomes, including biliary complications. Significant superiority of SPLC over MPLC was shorter hospitalization, lower NRS score, and favorable GIQLI.

CONCLUSIONS

From nationwide prospective data, SPLC showed outcomes comparable to MPLC. In SPLC, morbidity was not high and postoperative QoL was favorable. In the future, more implementations and studies are needed to ensure the safety and feasibility of SPLC.

Value of Conventional Ultrasound-based Scoring System in Distinguishing Adenomatous Polyps From Cholesterol Polyps

BACKGROUND AND AIM

Ultrasound has increased the detection of gallbladder polyps, but it has limitations in evaluating the nature of gallbladder polyps, especially the maximum size of 1.0 to 1.5 cm. We assessed the value of ultrasound scoring system based on independent predictive parameters in distinguishing adenomatous polyps from cholesterol polyps with the maximum size of 1.0 to 1.5 cm.

MATERIALS AND METHODS

We enrolled 163 patients with gallbladder polyps (1.0 to 1.5 cm) who underwent ultrasonography and cholecystectomy. Ultrasound image characteristics were compared between cholesterol polyps and adenomatous polyps in the training cohort from April 2018 to January 2020. An ultrasound scoring system was constructed in the training cohort, and its diagnostic performance was evaluated in the validation cohort from February 2020 to February 2021.

RESULTS

Maximum size, height/width ratio, stone or sludge, vascularity, and hyperechoic spot were significantly different between cholesterol polyps and adenomatous polyps in the training cohort ( P <0.05). The independent predictive parameters for adenomatous polyps were lower height/width ratio, presence of vascularity and absence of hyperechoic spot. The total score was as follows: (height/width ratio, <0.9=4, ≥0.9=0) + (vascularity, present=3, absent=0) + (hyperechoic spot, absent=2, present=0). The sensitivity, specificity and accuracy of ultrasound scoring system ≥5 for diagnosis of adenomatous polyps in the validation cohort were 73.33%, 80.49%, and 78.57%, respectively.

CONCLUSIONS

The ultrasound scoring system aids in distinguishing adenomatous polyps from cholesterol polyps, and effectively decreasing unnecessary cholecystectomy.

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.

Management and follow-up of gallbladder polyps: updated joint guidelines between the ESGAR, EAES, EFISDS and ESGE

Abstract

Main recommendations

Primary investigation of polypoid lesions of the gallbladder should be with abdominal ultrasound. Routine use of other imaging modalities is not recommended presently, but further research is needed. In centres with appropriate expertise and resources, alternative imaging modalities (such as contrast-enhanced and endoscopic ultrasound) may be useful to aid decision-making in difficult cases. Strong recommendation, low–moderate quality evidence.

Cholecystectomy is recommended in patients with polypoid lesions of the gallbladder measuring 10 mm or more, providing the patient is fit for, and accepts, surgery. Multidisciplinary discussion may be employed to assess perceived individual risk of malignancy. Strong recommendation, low-quality evidence.

Cholecystectomy is suggested for patients with a polypoid lesion and symptoms potentially attributable to the gallbladder if no alternative cause for the patient’s symptoms is demonstrated and the patient is fit for, and accepts, surgery. The patient should be counselled regarding the benefit of cholecystectomy versus the risk of persistent symptoms. Strong recommendation, low-quality evidence.

If the patient has a 6–9 mm polypoid lesion of the gallbladder and one or more risk factors for malignancy, cholecystectomy is recommended if the patient is fit for, and accepts, surgery. These risk factors are as follows: age more than 60 years, history of primary sclerosing cholangitis (PSC), Asian ethnicity, sessile polypoid lesion (including focal gallbladder wall thickening > 4 mm). Strong recommendation, low–moderate quality evidence.

If the patient has either no risk factors for malignancy and a gallbladder polypoid lesion of 6–9 mm, or risk factors for malignancy and a gallbladder polypoid lesion 5 mm or less, follow-up ultrasound of the gallbladder is recommended at 6 months, 1 year and 2 years. Follow-up should be discontinued after 2 years in the absence of growth. Moderate strength recommendation, moderate-quality evidence.

If the patient has no risk factors for malignancy, and a gallbladder polypoid lesion of 5 mm or less, follow-up is not required. Strong recommendation, moderate-quality evidence.

If during follow-up the gallbladder polypoid lesion grows to 10 mm, then cholecystectomy is advised. If the polypoid lesion grows by 2 mm or more within the 2-year follow-up period, then the current size of the polypoid lesion should be considered along with patient risk factors. Multidisciplinary discussion may be employed to decide whether continuation of monitoring, or cholecystectomy, is necessary. Moderate strength recommendation, moderate-quality evidence.

If during follow-up the gallbladder polypoid lesion disappears, then monitoring can be discontinued. Strong recommendation, moderate-quality evidence.

Source and scope

These guidelines are an update of the 2017 recommendations developed between the European Society of Gastrointestinal and Abdominal Radiology (ESGAR), European Association for Endoscopic Surgery and other Interventional Techniques (EAES), International Society of Digestive Surgery–European Federation (EFISDS) and European Society of Gastrointestinal Endoscopy (ESGE). A targeted literature search was performed to discover recent evidence concerning the management and follow-up of gallbladder polyps. The changes within these updated guidelines were formulated after consideration of the latest evidence by a group of international experts. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was adopted to define the strength of recommendations and the quality of evidence.

Key Point

• These recommendations update the 2017 European guidelines regarding the management and follow-up of gallbladder polyps.

Is there a role for growth status in distinguishing gallbladder adenomas from cholesterol polyps? - A retrospective study based on 520 cholecystectomy patients

INTRODUCTION

Gallbladder adenomas have cancerous potential and occur in 4-8.9% of gallbladder polyps. The growth status (size progression and growth rate during follow-up) of polyps and their effectiveness for predicting adenomas are poorly defined. Herein, we compared adenomas and cholesterol polyps based on the growth status and evaluated the reported risk factors in predicting neoplasm.

METHODS

We enrolled 520 patients who underwent preoperative ultrasonic follow-up more than 6 months with post-cholecystectomy pathologically confirmed gallbladder polyps. The patients were classified into adenoma and cholesterol polyp groups. Growth status, clinical characteristics, laboratory data, ultrasonic findings were reviewed and compared between the groups.

RESULTS

Seventy-nine adenomas and 441 cholesterol polyps were analyzed. The mean diameter of adenomas (cholesterol polyps) was 7.24 ± 4.36 mm (6.23 ± 2.88 mm) in the initial and 12.06 ± 4.61 mm (10.05 ± 2.95 mm) in the preoperative examination. The median size progression (range) of polyps in the cholesterol polyps [3 (0, 22)] mm was smaller than that in adenomas [4 (0, 21)] mm (p = .075). The mean growth rate of adenomas (1.07 ± 1.33 mm/6 months) was slightly faster than in cholesterol polyps (0.83 ± 1.04 mm/6 months) (p = .338). The indicators significantly associated with adenomas were age >49.5 years, lack of gallbladder polyps/cholelithiasis family history, polyp size >11.5 mm and solitary polyp (p = .005, p = .027, p = .001, and p = .021, respectively).

CONCLUSION

Growth status was not a valuable modality to distinguishing gallbladder adenomas from cholesterol polyps. Risk factors such as age, polyp size, and solitary polyp were effective in predicting adenomas.

How Can We Manage Gallbladder Lesions by Transabdominal Ultrasound?

The most important role of ultrasound (US) in the management of gallbladder (GB) lesions is to detect lesions earlier and differentiate them from GB carcinoma (GBC). To avoid overlooking lesions, postural changes and high-frequency transducers with magnified images should be employed. GB lesions are divided into polypoid lesions (GPLs) and wall thickening (GWT). For GPLs, classification into pedunculated and sessile types should be done first. This classification is useful not only for the differential diagnosis but also for the depth diagnosis, as pedunculated carcinomas are confined to the mucosa. Both rapid GB wall blood flow (GWBF) and the irregularity of color signal patterns on Doppler imaging, and heterogeneous enhancement in the venous phase on contrast-enhanced ultrasound (CEUS) suggest GBC. Since GWT occurs in various conditions, subdividing into diffuse and focal forms is important. Unlike diffuse GWT, focal GWT is specific for GB and has a higher incidence of GBC. The discontinuity and irregularity of the innermost hyperechoic layer and irregular or disrupted GB wall layer structure suggest GBC. Rapid GWBF is also useful for the diagnosis of wall-thickened type GBC and pancreaticobiliary maljunction. Detailed B-mode evaluation using high-frequency transducers, combined with Doppler imaging and CEUS, enables a more accurate diagnosis.

Malignancy in elective cholecystectomy due to gallbladder polyps or thickened gallbladder wall: a single-centre experience

INTRODUCTION

Gallbladder cancer is a rare but aggressive malignancy. Surgical resection is recommended for gallbladder polyps ≥10 mm. For gallbladder wall thickening, resection is recommended if malignancy cannot be excluded. The incidence of gallbladder malignancy after cholecystectomy with indications of polyps or wall thickening in the Swedish population is not known.

MATERIAL/METHODS

A retrospective study was performed at Linköping University Hospital and included patients who underwent cholecystectomy 2010 - 2018. All cholecystectomies performed due to gallbladder polyps or gallbladder wall thickening without other preoperative malignant signs were identified. Preoperative radiological examinations were re-analysed by a single radiologist. Medical records and histopathology reports were analysed.

RESULTS

In all, 102 patients were included, of whom 65 were diagnosed with gallbladder polyps and 37 with gallbladder wall thickening. In each group, one patient (1.5% and 2.7% in each group) had gallbladder malignancy ≥ pT1b.Two (3.1%) and three (8.1%) patients with gallbladder malignancy < T1b were identified in each group.

DISCUSSION/CONCLUSION

This study indicates that the incidence of malignancy is low without other malignant signs beyond gallbladder polyps and/or gallbladder wall thickening. We propose that these patients should be discussed at a multidisciplinary tumour board. If the polyp is 10-15 mm or if the gallbladder wall is thickened but no other malignant signs are observed, cholecystectomy can be safely performed by an experienced general surgeon at a general surgery unit. If the histopathology indicates ≥ pT1b, the patient should be referred immediately to a hepatobiliary centre for liver and lymph node resection.

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.

Gallbladder polyps: Correlation of size and clinicopathologic characteristics based on updated definitions

BACKGROUND

Different perspectives exist regarding the clinicopathologic characteristics, biology and management of gallbladder polyps. Size is often used as the surrogate evidence of polyp behavior and size of ≥1cm is widely used as cholecystectomy indication. Most studies on this issue are based on the pathologic correlation of polyps clinically selected for resection, whereas, the data regarding the nature of polypoid lesions from pathology perspective -regardless of the cholecystectomy indication- is highly limited.

METHODS

In this study, 4231 gallbladders -606 of which had gallbladder carcinoma- were reviewed carefully pathologically by the authors for polyps (defined as ≥2 mm). Separately, the cases that were diagnosed as "gallbladder polyps" in the surgical pathology databases were retrieved.

RESULTS

643 polyps identified accordingly were re-evaluated histopathologically. Mean age of all patients was 55 years (range: 20-94); mean polyp size was 9 mm. Among these 643 polyps, 223 (34.6%) were neoplastic: I. Non-neoplastic polyps (n = 420; 65.4%) were smaller (mean: 4.1 mm), occurred in younger patients (mean: 52 years). This group consisted of fibromyoglandular polyps (n = 196) per the updated classification, cholesterol polyps (n = 166), polypoid pyloric gland metaplasia (n = 41) and inflammatory polyps (n = 17). II. Neoplastic polyps were larger (mean: 21 mm), detected in older patients (mean: 61 years) and consisted of intra-cholecystic neoplasms (WHO's "adenomas" and "intracholecystic papillary neoplasms", ≥1 cm; n = 120), their "incipient" version (<1 cm) (n = 44), polypoid invasive carcinomas (n = 26) and non-neoplastic polyps with incidental dysplastic changes (n = 33). In terms of size cut-off correlations, overall, only 27% of polyps were ≥1 cm, 90% of which were neoplastic. All (except for one) ≥2 cm were neoplastic. However, 14% of polyps <1 cm were also neoplastic. Positive predictive value of ≥1 cm cut-off -which is widely used for cholecystectomy indication-, was 94.3% and negative predictive value was 85%.

CONCLUSIONS

Approximately a third of polypoid lesions in the cholecystectomies (regardless of the indication) prove to be neoplastic. The vast majority of (90%) of polyps ≥1 cm and virtually all of those ≥2 cm are neoplastic confirming the current impression that polyps ≥1 cm ought to be removed. However, this study also illustrates that 30% of the neoplastic polyps are <1 cm and therefore small polyps should also be closely watched, especially in older patients.

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.

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.”

Predictive Model for Neoplastic Potential of Gallbladder Polyp

GOAL

To provide the statistical predictive model for neoplastic potential of gallbladder polyp (GBP).

BACKGROUND

Many studies have attempted to define the risk factors for neoplastic potential of GBP. It remains difficult to precisely adapt the reported risk factors for the decision of surgery. Estimating the probability for neoplastic potential of GBP using a combination of several risk factors before surgical resection would be useful in patient consultation.

STUDY

We collected data of patients confirmed as GBP through cholecystectomy at Samsung Medical Center between January 1997 and March 2015. Those with a definite evidence for malignancy, such as adjacent organ invasion, metastasis on preoperative imaging studies, polyp >15 mm, and absence of proper preoperative ultrasonographic imaging were excluded. A total of 1976 patients were enrolled. To make and validate the predictive model, we divided the cohort into the modeling group (n=979) and validation group (n=997). Clinical information, ultrasonographic findings, and blood tests were retrospectively analyzed.

RESULTS

Clinical factors of older age, single lesion, sessile shape, and polyp size showed statistical significance for neoplastic potential of GBP in the modeling group. A predictive model for neoplastic potential of GBP was constructed utilizing the statistical outcome of the modeling group. Statistical validation was performed with the validation group to determine the optimal clinical sensitivity and specificity of the predictive model. Optimal cut-off value for neoplastic probability was 7.4%.

CONCLUSIONS

The predictive model for neoplastic potential of GBP may support clinical decisions before cholecystectomy.

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.

Risk stratification of gallbladder polyps larger than 10 mm using high-resolution ultrasonography and texture analysis

OBJECTIVES

To assess important features for risk stratification of gallbladder (GB) polyps >10 mm using high-resolution ultrasonography (HRUS) and texture analysis.

METHODS

We included 136 patients with GB polyps (>10 mm) who underwent both HRUS and cholecystectomy (non-neoplastic, n = 58; adenomatous, n = 32; and carcinoma, n = 46). Two radiologists retrospectively assessed HRUS findings and texture analysis. Multivariate analysis was performed to identify significant predictors for neoplastic polyps and carcinomas.

RESULTS

Single polyp (OR, 3.680-3.856) and larger size (OR, 1.450-1.477) were independently associated with neoplastic polyps (p < 0.05). In a single or polyp >14 mm, sensitivity for differentiating neoplastic from non-neoplastic polyps was 92.3%. To differentiate carcinoma from adenoma, sessile shape (OR, 9.485-41.257), larger size (OR, 1.267-1.303), higher skewness (OR, 6.382) and lower grey-level co-occurrence matrices (GLCM) contrast (OR, 0.963) were significant predictors (p < 0.05). In a polyp >22 mm or sessile, sensitivity for differentiating carcinomas from adenomas was 93.5-95.7%. If a polyp demonstrated at least one HRUS finding and at least one texture feature, the specificity for diagnosing carcinoma was increased to 90.6-93.8%.

CONCLUSION

In a GB polyp >10 mm, single and diameter >14 mm were useful for predicting neoplastic polyps. In neoplastic polyps, sessile shape, diameter >22 mm, higher skewness and lower GLCM contrast were useful for predicting carcinoma.

KEY POINTS

• Risk of neoplastic polyp is low in <14 mm and multiple polyps • A sessile polyp or >22 mm has increased risk for GB carcinomas • Higher skewness and lower GLCM contrast are predictors of GB carcinoma • HRUS is useful for risk stratification of GB polyps >1 cm.

Management and follow-up of gallbladder polyps : Joint guidelines between the European Society of Gastrointestinal and Abdominal Radiology (ESGAR), European Association for Endoscopic Surgery and other Interventional Techniques (EAES), International Society of Digestive Surgery - European Federation (EFISDS) and European Society of Gastrointestinal Endoscopy (ESGE)

Objectives

The management of incidentally detected gallbladder polyps on radiological examinations is contentious. The incidental radiological finding of a gallbladder polyp can therefore be problematic for the radiologist and the clinician who referred the patient for the radiological examination. To address this a joint guideline was created by the European Society of Gastrointestinal and Abdominal Radiology (ESGAR), European Association for Endoscopic Surgery and other Interventional Techniques (EAES), International Society of Digestive Surgery – European Federation (EFISDS) and European Society of Gastrointestinal Endoscopy (ESGE).

Methods

A targeted literature search was performed and consensus guidelines were created using a series of Delphi questionnaires and a seven-point Likert scale.

Results

A total of three Delphi rounds were performed. Consensus regarding which patients should have cholecystectomy, which patients should have ultrasound follow-up and the nature and duration of that follow-up was established. The full recommendations as well as a summary algorithm are provided.

Conclusions

These expert consensus recommendations can be used as guidance when a gallbladder polyp is encountered in clinical practice.

Key Points

• Management of gallbladder polyps is contentious

• Cholecystectomy is recommended for gallbladder polyps >10 mm

• Management of polyps <10 mm depends on patient and polyp characteristics

• Further research is required to determine optimal management of gallbladder polyps