Incidental gallbladder carcinoma: Utility of histopathological evaluation of routine cholecystectomy specimens

Advancements in Cholelithiasis Diagnosis: A Systematic Review of Machine Learning Applications in Imaging Analysis

Gallstone disease is a common condition affecting a substantial number of individuals globally. The risk factors for gallstones include obesity, rapid weight loss, diabetes, and genetic predisposition. Gallstones can lead to serious complications such as calculous cholecystitis, cholangitis, biliary pancreatitis, and an increased risk for gallbladder (GB) cancer. Abdominal ultrasound (US) is the primary diagnostic method due to its affordability and high sensitivity, while computed tomography (CT) and magnetic resonance cholangiopancreatography (MRCP) offer higher sensitivity and specificity. This review assesses the diagnostic accuracy of machine learning (ML) technologies in detecting gallstones. This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines for reporting systematic reviews and meta-analyses. An electronic search was conducted in PubMed, Cochrane Library, Scopus, and Embase, covering literature up to April 2024, focusing on human studies, and including all relevant keywords. Various Boolean operators and Medical Subject Heading (MeSH) terms were used. Additionally, reference lists were manually screened. The review included all study designs and performance indicators but excluded studies not involving artificial intelligence (AI)/ML algorithms, non-imaging diagnostic modalities, microscopic images, other diseases, editorials, commentaries, reviews, and studies with incomplete data. Data extraction covered study characteristics, imaging modalities, ML architectures, training/testing/validation, performance metrics, reference standards, and reported advantages and drawbacks of the diagnostic models. The electronic search yielded 1,002 records, of which 34 underwent full-text screening, resulting in the inclusion of seven studies. An additional study identified through citation searching brought the total to eight articles. Most studies employed a retrospective cross-sectional design, except for one prospective study. Imaging modalities included ultrasonography (four studies), computed tomography (three studies), and magnetic resonance cholangiopancreatography (one study). Patient numbers ranged from 60 to 2,386, and image numbers ranged from 60 to 17,560 images included in the training, validation, and testing of the diagnostic models. All studies utilized neural networks, predominantly convolutional neural networks (CNNs). Expert radiologists served as the reference standard for image labelling, and model performances were compared against human doctors or other algorithms. Performance indicators such as sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were commonly used. In conclusion, while the reviewed machine learning models show promising performance in diagnosing gallstones, significant work remains to be done to ensure their reliability and generalizability across diverse clinical settings. The potential for these models to improve diagnostic accuracy and efficiency is evident, but the careful consideration of their limitations and rigorous validation are essential steps toward their successful integration into clinical practice.

Post-operative complications of cholecystectomy: what the radiologist needs to know

Cholecystectomy is one of the most performed surgical procedures. The safety of this surgery notwithstanding, the sheer volume of operations results in a notable incidence of post-cholecystectomy complications. Early and accurate diagnosis of such complications is essential for timely and effective management. Imaging techniques are critical for this purpose, aiding in distinguishing between expected postsurgical changes and true complications. This review highlights current knowledge on the indications for cholecystectomy, pertinent surgical anatomy and surgical technique, and the recognition of anatomical variants that may complicate surgery. The article also outlines the roles of various imaging modalities in identifying complications, the spectrum of possible postsurgical anatomical changes, and the implications of such findings. Furthermore, we explore the array of complications that can arise post-cholecystectomy, such as biliary system injuries, gallstone-related issues, vascular complications, and the formation of postsurgical collections. Radiologists should be adept at identifying normal and abnormal postoperative findings to guide patient management effectively.

Incidental gallbladder cancer: what is the prevalence and how do we perform cholecystectomy for presumably benign biliary disease?

OBJECTIVE

to determine the prevalence of incidental gallbladder cancer (IGBC) in cholecystectomies performed in a tertiary public hospital and to describe technical and epidemiological aspects of performing cholecystectomies for presumably benign disease.

METHOD

descriptive, retrospective observational study, based on analysis of medical records of patients undergoing cholecystectomy with preoperative hypothesis of benign disease between January 2018 and January 2022.

RESULTS

prevalence of gallbladder adenocarcinoma in our sample was 0.16%, similar to data in the literature. Technical aspects during cholecystectomy were also described with a frequency similar to that found in the literature.

CONCLUSION

despite a rare disease, IGBC is relevant in the routine of the General Surgeon. Its diagnosis, staging and treatment directly affect the prognosis. Technical aspects during cholecystectomy are not always remembered by surgeons and can interfere with the prognosis and subsequent treatment of the patient.

Incidental Gallbladder Neoplasms: A Growing Global Burden

Background

The increasing trend of laparoscopic procedures has made cholecystectomies one of the most common surgical specimens received for histopathological evaluation. This has also led to an increasing trend of finding incidental gallbladder malignancies for a presumed benign disease. The present study describes the histopathological spectrum of neoplastic lesions of the gallbladder along with the historadiological correlation with special emphasis on incidental gallbladder carcinomas (IGBC).

Materials and methods

All the cholecystectomies received over a span of two and a half years were studied. Demographic details, imaging findings, gross features, and microscopic findings of premalignant and malignant lesions were noted. Special stains were done as and when required.

Results

Of the 1253 cholecystectomies received during the study period, 50 gallbladders (3.9%) showed neoplastic pathology and were included in the present study. The age range was 40 to 60 years with female predominance. Ultrasonography revealed nonspecific wall thickness in both premalignant and incidental gallbladder carcinomas. Gallstones were seen in 74% of the cases (37/50). Gross and imaging findings in 17 (34%) of the malignant cases were in concordance with microscopic features, whereas the dysplastic lesions (21) and IGBC cases showed evidence of chronic cholecystitis on the same. Microscopic examination revealed focal dysplasia (low and high grade) in 21/50 (42%) cases. Invasive malignancy was seen in 28/50 (56%) of the cases, of which 11 cases (22%) were IGBC. Pancreaticobiliary type of adenocarcinoma was the most common morphology seen in almost all the cases. There was also one case each of intracholecystic papillary neoplasm (ICPN) and carcinosarcoma.

Conclusion

GBC is an unusual malignancy and its preoperative diagnosis is not so definitive. The incidental form of GBC presents as a radiological disguise and a histopathological surprise. Hence, the present study warrants a complete and scrupulous histopathological examination of all the cholecystectomy specimens for proper and further management of the case.

Câncer incidental de vesícula biliar: qual a prevalência e como operamos a colecistectomia por doença presumidamente benigna?

RESUMO Objetivos: determinar a prevalência de câncer incidental de vesícula biliar (CIVB) em colecistectomias realizadas em um hospital público terciário e descrever aspectos técnicos e epidemiológicos na realização de colecistectomias por doença presumidamente benigna. Método: estudo observacional descritivo, retrospectivo, a partir da análise de prontuários de pacientes submetidos à colecistectomia com hipótese pré-operatória de doença benigna entre janeiro de 2018 e janeiro de 2022. Resultados: a prevalência de adenocarcinoma de vesícula biliar na amostra avaliada foi de 0,16%, semelhante aos dados da literatura mundial. Os aspectos técnicos durante a realização da colecistectomia também foram descritos com frequência semelhante ao encontrado na literatura. Conclusão: o CIVB é uma doença rara mas de importância relevante na rotina do Cirurgião Geral. Seu diagnóstico, estadiamento e tratamento implicam diretamente no prognóstico. Aspectos técnicos durante a realização da colecistectomia nem sempre são lembrados pelos cirurgiões e podem interferir no prognóstico e tratamento subsequente do paciente.

Segnet Network Algorithm-Based Ultrasound Images in the Diagnosis of Gallbladder Stones Complicated with Gallbladder Carcinoma and the Relationship between P16 Expression with Gallbladder Carcinoma

The study focused on how to improve the diagnostic coincidence rate of patients with gallbladder stones and gallbladder cancer based on an optimized Segnet network algorithm and the relationship of gallbladder cancer with multiple tumor suppressor 1 (P16). 300 patients diagnosed with gallbladder cancer in the hospital were selected as the research subjects. The pyramid pooling operation was incorporated into the original Segnet network algorithm, and its performance was evaluated, factoring into the intersection of union (IoU), algorithm precision (Pre), and recall rate (Recall). After 8 hours of fasting, conventional ultrasound and contrast-enhanced ultrasound examinations were performed, and the images were evaluated by three experienced ultrasound diagnosticians. The positive signal of P16 immunohistochemical staining was brownish yellow, which was generally concentrated in the nucleus, and a small part was located in the cytoplasm. In each slice, ten visual fields were selected. Then, they were observed under a high-power mirror, and the number was counted. It was found that the optimized Segnet network algorithm increased the IoU by 7.3%, the precision by 8.2%, and the recall rate by 11.1%. The diagnostic coincidence rates of conventional ultrasound and contrast-enhanced ultrasound examinations for gallbladder cancer were 78.13% (25/32) and 87.5% (25/32), respectively. The positive expression rate of P16 in gallbladder adenocarcinoma (47.06%) was significantly lower than that of acute cholecystitis with gallbladder stones (84.38%) and gallbladder polyps (67.16%) (P < 0.05). The positive expression rate of P16 in patients with stage III and stage IV (33.33% and 40%) was significantly lower than that in patients with stages I and II (87.5% and 80%) (P < 0.05). The positive expression rate of P16 in high differentiation (86.67%) was significantly higher than that of moderate differentiation (40%) and poor differentiation (28.57%) (P < 0.05). In short, contrast-enhanced ultrasound can effectively improve the diagnostic coincidence rate of gallbladder cancer, and the expression of P16 in gallbladder cancer is closely related to tumor staging and differentiation.

Thirty-five cases of gallbladder carcinoma out of 4914 cholecystectomy specimens from a Nepalese tertiary care hospital - A retrospective cohort study

Introduction

The density of gallbladder carcinoma differs in different parts of the world. It is an aggressive tumor with poor prognosis presenting in advanced stages due to paucity of signs and symptoms. This research was conducted to analyze the frequency of incidental and clinically suspected gallbladder carcinoma with clinicopathological correlation.

Methods

This is a retrospective cohort study conducted in the Department of Pathology, Manipal College of Medical Sciences, Pokhara, Nepal from January 2005 to December 2020.

Results

The study included 35 cases of gallbladder carcinoma compiled over a period of 16 years. There were 11 males and 24 females with a male to female ratio of 1: 2.1. Age ranged from 29 to 75 years with a mean age of 56.51 ± 11.38 years. Incidental carcinoma was observed in 26 (74.28%) cases while clinically suspected carcinoma was identified in 9 (25.71%) cases. Gallstone was associated in 14 (40%) cases of incidental carcinoma. Tumor staging of both incidental and clinically suspected carcinomas showed 13 (37.14%) cases in T1 stage, 15 (42.85%) cases in T2 stage and 7(20%) cases in T3 stage.

Conclusion

Our analysis established prevalance of gallbladder carcinoma from 5th to 7th decades with female predominance and higher association of gallstones in incidental carcinoma. The principal histology in incidental carcinoma was well differentiated carcinoma while poorly differentiated carcinoma was encountered only in clinically suspected carcinoma.

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Gallbladder carcinoma is an aggressive tumor with poor prognosis.

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Early diagnosis of gallbladder carcinoma is rare.

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Incidental carcinomas are more frequent than clinically suspected carcinomas.

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Incidental carcinomas have more association with gallstones.

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Clinically suspected carcinoma shows higher stage of tumor.

Incidental Gallbladder Carcinoma in North Indian Population: Importance of Routine Histopathological Examination of All Benign Gallbladder Specimens

AIM

To evaluate the incidence of incidental gallbladder carcinoma in specimens of cholecystectomy performed for benign gallbladder diseases and to establish the utility of routine histopathological examination of all gallbladder specimens obtained following cholecystectomy done for benign diseases.

MATERIAL AND METHODS

 This was a hospital-based three years prospective and retrospective study done at a tertiary care centre in North India. Gallbladder specimens from laparoscopic and open cholecystectomies done for benign gallbladder diseases without any clinico-radiological evidence of malignancy were included in the study. Routine histopathological evaluation of 1,268 such gallbladder specimens was carried out to get the incidence of incidental gallbladder carcinoma and pathological staging of carcinoma was done according to American Joint Committee recommendations for cancer staging (AJCC). All the diagnosed cases of Incidental gallbladder carcinoma (IGBC) were analysed in terms of demographics, radiology findings, and gross and microscopic pathology findings.

RESULTS

Out of 1,268 gallbladder specimens of clinically benign diseases, 16 cases (1.26%) were diagnosed as cases of IGBC with female predominance with a male to female ratio of 1:7. Mean gallbladder thickness in these cases was 0.77±0.20 cm, and 98.30% cases of IGBC were associated with gall stone disease. However, no correlation was observed between the age, gallbladder thickness and pathological stages of these IGBC.

CONCLUSION

 IGBC is an occult disastrous malignancy of the gallbladder, which can be missed in the pre and intraoperative periods despite careful clinical and radiological evaluation and comes as a surprise for pathologists the first time. We recommend that all specimens of gallbladder obtained from its surgical resection for benign diseases should be subjected to histopathological examination.

Selective or Routine Histology of Cholecystectomy Specimens for Diagnosing Incidental Carcinoma of Gallbladder and Correlation with Careful Intraoperative Macroscopic Examination? A Systematic Review

BACKGROUND

Selective or Routine histology of cholecystectomy specimens for benign gallbladder disease has always been a matter of debate because of the low prevalence and bad prognosis associated with gall bladder carcinoma. The objective of this study is to ascertain whether selective histology can be preferred over Routine histology without any harm.

METHODS

This systematic review is conducted according to PRISMA's checklist; relevant articles were searched in the database until September 1 2020 in PubMed, Scopus, Science Direct, and Web of Science databases, manually, with search queries and without date restrictions. Studies included in this systematic review involved patients who underwent cholecystectomy for benign gallbladder disease and were diagnosed with gallbladder carcinoma incidentally either after selective or routine histology of the gallbladder.

RESULTS

A total of 24 routine or selective histology recommending studies were selected for the systematic review after following the inclusion and exclusion criteria. These studies comprised 77,213 numbers of patients and 486 numbers of Malignancies. These studies correlate the number of IGBC diagnosed histologically with the number of IGBC's that were suspected by the surgeons intraoperative by macroscopy. Routine recommending studies show a significant number of IGBC diagnosed histologically as missed by surgeons whereas the selective recommending studies show most of the histologically diagnosed IGBC already suspected by the surgeons intraoperative. When comparing the macroscopic details of the IGBC's between routine and selective studies, we found that there was significant overlap. Most of the findings missed by the surgeons as suspicious in routine studies were suspected by the surgeons involved in selective histology recommending studies. Thereby, favouring selective histology and emphasizing the need for careful intraoperative macroscopy for suspecting IGBC.

CONCLUSION

Selective Histological examination of cholecystectomy specimens can be preferred if a careful intraoperative macroscopic examination is done and patient risk factors are taken into consideration.

Safe, selective histopathological examination of gallbladder specimens: a systematic review

Background

Routine histopathological examination after cholecystectomy is costly, but the prevalence of unsuspected gallbladder cancer (incidental GBC) is low. This study determined whether selective histopathological examination is safe.

Methods

A comprehensive search of PubMed, Embase, Web of Science and the Cochrane Library was performed. Pooled incidences of incidental and truly incidental GBC (GBC detected during histopathological examination without preoperative or intraoperative suspicion) were estimated using a random‐effects model. The clinical consequences of truly incidental GBC were assessed.

Results

Seventy‐three studies (232 155 patients) were included. In low‐incidence countries, the pooled incidence was 0·32 (95 per cent c.i. 0·25 to 0·42) per cent for incidental GBC and 0·18 (0·10 to 0·35) per cent for truly incidental GBC. Subgroup analysis of studies in which surgeons systematically examined the gallbladder revealed a pooled incidence of 0·04 (0·01 to 0·14) per cent. In high‐incidence countries, corresponding pooled incidences were 0·83 (0·58 to 1·18), 0·44 (0·21 to 0·91) and 0·08 (0·02 to 0·39) per cent respectively. Clinical consequences were reported for 176 (39·3 per cent) of 448 patients with truly incidental GBC. Thirty‐three patients (18·8 per cent) underwent secondary surgery. Subgroup analysis showed that at least half of GBC not detected during the surgeon's systematic examination of the gallbladder was early stage (T1a status or below) and of no clinical consequence.

Conclusion

Selective histopathological examination of the gallbladder after initial macroscopic assessment by the surgeon seems safe and could reduce costs.

Incidental Carcinoma after Cholecystectomy for Benign Disease of the Gallbladder: A Meta-Analysis

This study aimed to determine the incidence and the prognosis of incidental carcinoma of the gallbladder (IGBC) after cholecystectomy through a meta-analysis. This meta-analysis included 51 studies and 436,636 patients with cholecystectomy. The incidence rate of IGBC after cholecystectomy was 0.6% (95% confidence interval (CI) 0.5%-0.8%). The incidence rate of recent studies was not significantly different from those of past studies. The mean age and female ratio of the IGBC subgroup were not significantly different from those of the overall patient group. The estimated rates of IGBC were 13.0%, 34.1%, 39.7%, 22.7%, and 12.5% in the pTis, pT1, pT2, pT3, and pT4 stages, respectively. Patients with IGBC had a favorable overall survival rate compared to patients with non-IGBC (hazard ratio (HR) 0.574, 95% CI 0.445-0.739). However, there was no significant difference of disease-free survival between the IGBC and non-IGBC subgroups (HR 0.931, 95% CI 0.618-1.402). IGBC was found in 0.6% of patients with cholecystectomy. The prognosis of patients with IGBC was favorable compared to those with non-IGBC. In the pathologic examination after cholecystectomy for benign diseases, a sufficient examination for histology should be guaranteed to detect IGBC.

Systematic Selective Sampling of Cholecystectomy Specimens Is Adequate to Detect Incidental Gallbladder Adenocarcinoma

Many gallbladder adenocarcinomas (ACs) are detected incidentally in routine cholecystectomy specimens, yet sampling practices vary when intestinal metaplasia (IM) or dysplasia are found via routine sampling. Our practice has been to submit 5 additional sections when IM is found, but cases with dysplasia are entirely submitted. We sought to determine an appropriate sampling protocol when encountering these findings. We retrospectively identified cholecystectomy specimens with these features over a 26-month period, yielding 48 of 4059 (1%) cases. Four pathologists independently classified the (2 longitudinal and 1 cystic duct margin) original sections into 1 of 3 categories (IM, low-grade dysplasia [LGD] or high-grade dysplasia [HGD]); initial findings were correlated with final diagnoses. Sixteen (33%) cases had additional findings upon further sampling, including LGD (n=10) or HGD (n=4) and AC (n=2). HGD always accompanied malignancy. We prospectively analyzed 39 of 3133 (1%) additional cholecystectomy specimens, initially submitting the same routine sections. We submitted 5 random sections from cases with IM. Cases with LGD were first examined with 1 additional section per centimeter. All remaining tissue was submitted in all of these cases and separately reviewed. Cases with HGD were entirely submitted as both test cases with HGD in initial sections ultimately showed carcinoma. This protocol detected all cases of HGD and AC. Patients with clear cystic duct margins did not experience neoplastic progression, even if dysplasia was present elsewhere. We conclude gallbladders with HGD should be entirely submitted, LGD may be representatively sampled, and routine sampling is adequate for IM.

A Comparative Analysis of Clinical Characteristics and Histomorphologic and Immunohistochemical Spectrum of Gallbladder Carcinoma in Young Adults (< 45 Years) and Elderly Adults (> 60 Years)

Gallbladder carcinoma (GBC) is more frequent after 60 years of age; its behavior in young adults has not been much studied. A retrospective analysis was performed in patients who underwent a cholecystectomy procedure between the years 2001 to 2016. A group of young patients (< 45) were compared with elderly patients (> 60 years) with reference to various clinical, histomorphologic, and immunohistochemical parameters. Statistical analysis was performed using t test and Fisher's test. Survival curves were calculated by Kaplan-Meier actuarial survival curves and log-rank tests. One hundred and one patients with GBC were observed during the study period. Of these, 14 patients (13.9%) belonged to the study group (age range 20 to 45 years) and 43 patients (42.6%) constituted the comparison elderly control group (age range 60 to 80 years). Forty-four pts. were in the middle-aged group (46 to 59 years) and were thus excluded from the study. With reference to age (< 45 and > 60), no significant difference was found in sex (females 64.3% vs 69.8%, p = 0.7), presence of gall stones (64% vs 60%, p = 0.8), advanced disease at presentation (T4) (14.3% vs 7%, p = 0.40), incidental detection of gallbladder carcinoma (28.5% vs 28%, p = 0.9), tumor stage at presentation (stage I/II) (35.7% vs 49%, p = 0.39), and poor differentiation (tumor grades G3) (14% vs 12%, p = 0.79). Full-length involvement (28.5% vs 11.6%, p = 0.015) of the gallbladder and abundant tumor necrosis (43% vs 14%, p = 0.021) were more common in the younger patients group whereas adenosquamous and pure squamous cell carcinoma were predominantly observed in elderly patients. Immunohistochemical studies showed higher percentage of overexpression of p53 and Ki-67 proliferation indices in the younger population. Overall survival in younger patients was 48 months whereas in elderly patients it was 36 months. Histological markers denoting aggressive tumor behavior were observed in gallbladder carcinomas of younger individuals; further studies are needed to delineate the differences in molecular mechanisms involved in progression of the tumor in the two groups.

Laparoscopic Cholecystectomy for Symptomatic Cholecystic Disease in Children: Defining Surgical Timing

Background: Laparoscopic cholecystectomy (LC) is the standard of care for gallbladder (GB) pathologies. We evaluated clinical, ultrasonographic (US) data as well as histopathological findings in children affected with symptomatic cholecystic disease (SCD) who underwent LC, with the aim of defining surgical timing. Methods: We reviewed our cases who underwent elective LC (ELC) or urgent LC (ULC). Clinical, US, surgical and histological features were used to create different risk scores. Results: We considered 26 children (17 ELC/9 ULC). US signs were not different in the two groups (p > 0.05). Operating times were longer in ELC than in ULC (p = 0.01). Histopathological evaluation revealed fibrosis and atrophy in both ELC and ULC. The clinical risk score was higher in ELC compared to ULC (p < 0.001). An increased operative risk score was noted in patients with systemic inflammatory signs (OR1.98), lithotherapy (OR1.4.3) and wall thickening ≥3 mm (OR2.6). An increased histopathological risk score was detected in children with symptom duration >7 days (OR3.61), concomitant hematological disease (OR1.23) and lithotherapy (OR3.61). Conclusion: Criteria adopted in adults cannot be adopted to detect the severity of GB damage in children. A dedicated clinical and US score is mandatory to define the most appropriate surgical timing.

Analysis of Incidental Gallbladder Cancer in Cholecystectomies

OBJECTIVE

To study incidental gallbladder cancer (IGBC) incidence in patients who underwent cholecystectomy.

METHODS

The records of patients who underwent cholecystectomy between 2004-2019 were retrospectively reviewed. The demographic information, preoperative radiological findings of the patients diagnosed with gallbladder cancer (GBC), as a result of routine histopathological examination and operation records, were reviewed and findings were recorded. The preoperative radiological records of the patients with GBC and, if any, findings of GBC suspected during surgery were recorded.

RESULTS

Between 2004-2019, a total of 6314 patients underwent cholecystectomy. Of the patients, 5404 (85.59%) were female and 910 (14.41%) were male. The median age was 47 years (min:19, max:94) and the mean age was 47.28±14.60 years. Nine out of 6314 patients (0.14%) were diagnosed with GBC by postoperative histopathological examination. All patients with GBC were female and their mean age was 64.33±11.08 years. Two out of nine GBC cases were prediagnosed with GBC in preoperative radiological findings; the remaining seven (0.11%) had IGBC without any preoperative findings.

CONCLUSION

Asian populations are reported to have a higher incidence of GBC. Turkey is located in the transition zone between Asia and Europe. However, the GBC rates in our study remain far below the rates reported in Asian publications. We believe that our results may be affected by the predominantly Mediterranean-type diet and the relatively higher socioeconomic level of the region where we conducted our study. Consequently, we recommend routine histopathological examination after cholecystectomies in regions with a high incidence of GBC.