Gallbladder metastasis: spectrum of imaging findings

Radiomics and machine learning analysis by computed tomography and magnetic resonance imaging in colorectal liver metastases prognostic assessment

OBJECTIVE

The aim of this study was the evaluation radiomics analysis efficacy performed using computed tomography (CT) and magnetic resonance imaging in the prediction of colorectal liver metastases patterns linked to patient prognosis: tumor growth front; grade; tumor budding; mucinous type. Moreover, the prediction of liver recurrence was also evaluated.

METHODS

The retrospective study included an internal and validation dataset; the first was composed by 119 liver metastases from 49 patients while the second consisted to 28 patients with single lesion. Radiomic features were extracted using PyRadiomics. Univariate and multivariate approaches including machine learning algorithms were employed.

RESULTS

The best predictor to identify tumor growth was the Wavelet_HLH_glcm_MaximumProbability with an accuracy of 84% and to detect recurrence the best predictor was wavelet_HLH_ngtdm_Complexity with an accuracy of 90%, both extracted by T1-weigthed arterial phase sequence. The best predictor to detect tumor budding was the wavelet_LLH_glcm_Imc1 with an accuracy of 88% and to identify mucinous type was wavelet_LLH_glcm_JointEntropy with an accuracy of 92%, both calculated on T2-weigthed sequence. An increase statistically significant of accuracy (90%) was obtained using a linear weighted combination of 15 predictors extracted by T2-weigthed images to detect tumor front growth. An increase statistically significant of accuracy at 93% was obtained using a linear weighted combination of 11 predictors by the T1-weigthed arterial phase sequence to classify tumor budding. An increase statistically significant of accuracy at 97% was obtained using a linear weighted combination of 16 predictors extracted on CT to detect recurrence. An increase statistically significant of accuracy was obtained in the tumor budding identification considering a K-nearest neighbors and the 11 significant features extracted T1-weigthed arterial phase sequence.

CONCLUSIONS

The results confirmed the Radiomics capacity to recognize clinical and histopathological prognostic features that should influence the choice of treatments in colorectal liver metastases patients to obtain a more personalized therapy.

Recent Advances in Ultrasound Breast Imaging: From Industry to Clinical Practice

Breast ultrasound (US) has undergone dramatic technological improvement through recent decades, moving from a low spatial resolution, grayscale-limited technique to a highly performing, multiparametric modality. In this review, we first focus on the spectrum of technical tools that have become commercially available, including new microvasculature imaging modalities, high-frequency transducers, extended field-of-view scanning, elastography, contrast-enhanced US, MicroPure, 3D US, automated US, S-Detect, nomograms, images fusion, and virtual navigation. In the subsequent section, we discuss the broadened current application of US in breast clinical scenarios, distinguishing among primary US, complementary US, and second-look US. Finally, we mention the still ongoing limitations and the challenging aspects of breast US.

Risk Assessment and Cholangiocarcinoma: Diagnostic Management and Artificial Intelligence

Intrahepatic cholangiocarcinoma (iCCA) is the second most common primary liver tumor, with a median survival of only 13 months. Surgical resection remains the only curative therapy; however, at first detection, only one-third of patients are at an early enough stage for this approach to be effective, thus rendering early diagnosis as an efficient approach to improving survival. Therefore, the identification of higher-risk patients, whose risk is correlated with genetic and pre-cancerous conditions, and the employment of non-invasive-screening modalities would be appropriate. For several at-risk patients, such as those suffering from primary sclerosing cholangitis or fibropolycystic liver disease, the use of periodic (6-12 months) imaging of the liver by ultrasound (US), magnetic Resonance Imaging (MRI)/cholangiopancreatography (MRCP), or computed tomography (CT) in association with serum CA19-9 measurement has been proposed. For liver cirrhosis patients, it has been proposed that at-risk iCCA patients are monitored in a similar fashion to at-risk HCC patients. The possibility of using Artificial Intelligence models to evaluate higher-risk patients could favor the diagnosis of these entities, although more data are needed to support the practical utility of these applications in the field of screening. For these reasons, it would be appropriate to develop screening programs in the research protocols setting. In fact, the success of these programs reauires patient compliance and multidisciplinary cooperation.

Immunotherapy Assessment: A New Paradigm for Radiologists

Immunotherapy denotes an exemplar change in an oncological setting. Despite the effective application of these treatments across a broad range of tumors, only a minority of patients have beneficial effects. The efficacy of immunotherapy is affected by several factors, including human immunity, which is strongly correlated to genetic features, such as intra-tumor heterogeneity. Classic imaging assessment, based on computed tomography (CT) or magnetic resonance imaging (MRI), which is useful for conventional treatments, has a limited role in immunotherapy. The reason is due to different patterns of response and/or progression during this kind of treatment which differs from those seen during other treatments, such as the possibility to assess the wide spectrum of immunotherapy-correlated toxic effects (ir-AEs) as soon as possible. In addition, considering the unusual response patterns, the limits of conventional response criteria and the necessity of using related immune-response criteria are clear. Radiomics analysis is a recent field of great interest in a radiological setting and recently it has grown the idea that we could identify patients who will be fit for this treatment or who will develop ir-AEs.

Imaging Features of Main Hepatic Resections: The Radiologist Challenging

Liver resection is still the most effective treatment of primary liver malignancies, including hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), and of metastatic disease, such as colorectal liver metastases. The type of liver resection (anatomic versus non anatomic resection) depends on different features, mainly on the type of malignancy (primary liver neoplasm versus metastatic lesion), size of tumor, its relation with blood and biliary vessels, and the volume of future liver remnant (FLT). Imaging plays a critical role in postoperative assessment, offering the possibility to recognize normal postoperative findings and potential complications. Ultrasonography (US) is the first-line diagnostic tool to use in post-surgical phase. However, computed tomography (CT), due to its comprehensive assessment, allows for a more accurate evaluation and more normal findings than the possible postoperative complications. Magnetic resonance imaging (MRI) with cholangiopancreatography (MRCP) and/or hepatospecific contrast agents remains the best tool for bile duct injuries diagnosis and for ischemic cholangitis evaluation. Consequently, radiologists should be familiar with the surgical approaches for a better comprehension of normal postoperative findings and of postoperative complications.

Risk Assessment and Pancreatic Cancer: Diagnostic Management and Artificial Intelligence

Pancreatic cancer (PC) is one of the deadliest cancers, and it is responsible for a number of deaths almost equal to its incidence. The high mortality rate is correlated with several explanations; the main one is the late disease stage at which the majority of patients are diagnosed. Since surgical resection has been recognised as the only curative treatment, a PC diagnosis at the initial stage is believed the main tool to improve survival. Therefore, patient stratification according to familial and genetic risk and the creation of screening protocol by using minimally invasive diagnostic tools would be appropriate. Pancreatic cystic neoplasms (PCNs) are subsets of lesions which deserve special management to avoid overtreatment. The current PC screening programs are based on the annual employment of magnetic resonance imaging with cholangiopancreatography sequences (MR/MRCP) and/or endoscopic ultrasonography (EUS). For patients unfit for MRI, computed tomography (CT) could be proposed, although CT results in lower detection rates, compared to MRI, for small lesions. The actual major limit is the incapacity to detect and characterize the pancreatic intraepithelial neoplasia (PanIN) by EUS and MR/MRCP. The possibility of utilizing artificial intelligence models to evaluate higher-risk patients could favour the diagnosis of these entities, although more data are needed to support the real utility of these applications in the field of screening. For these motives, it would be appropriate to realize screening programs in research settings.

Microbubble-Assisted Ultrasound for Imaging and Therapy of Melanoma Skin Cancer: A Systematic Review

Recent technological developments in ultrasound (US) imaging and ultrasound contrast agents (UCAs) have improved diagnostic confidence in echography. In the clinical management of melanoma, contrast-enhanced ultrasound (CEUS) imaging complements conventional US imaging (i.e., high-resolution US and Doppler imaging) for clinical examination and therapeutic follow-up. These developments have set into motion the combined use of ultrasound and UCAs as a new modality for drug delivery. This modality, called sonoporation, has emerged as a non-invasive, targeted and safe method for the delivery of therapeutic drugs into melanoma. This review focuses on the results and prospects of using US and UCAs as dual modalities for CEUS imaging and melanoma treatment.

Imaging Features of Main Posthepatectomy Complications: A Radiologist’s Challenge

In the recent years, the number of liver resections has seen an impressive growth. Usually, hepatic resections remain the treatment of various liver diseases, such as malignant tumors, benign tumors, hydatid disease, and abscesses. Despite technical advancements and tremendous experience in the field of liver resection of specialized centers, there are moderately high rates of postoperative morbidity and mortality, especially in high-risk and older patient populations. Although ultrasonography is usually the first-line imaging examination for postoperative complications, Computed Tomography (CT) is the imaging tool of choice in emergency settings due to its capability to assess the whole body in a few seconds and detect all possible complications. Magnetic resonance cholangiopancreatography (MRCP) is the imaging modality of choice for delineating early postoperative bile duct injuries and ischemic cholangitis that may arise in the late postoperative phase. Moreover, both MDCT and MRCP can precisely detect tumor recurrence. Consequently, radiologists should have knowledge of these surgical procedures for better comprehension of postoperative changes and recognition of the radiological features of various postoperative complications.

Gallbladder reporting and data system (GB-RADS) for risk stratification of gallbladder wall thickening on ultrasonography: an international expert consensus

The Gallbladder Reporting and Data System (GB-RADS) ultrasound (US) risk stratification is proposed to improve consistency in US interpretations, reporting, and assessment of risk of malignancy in gallbladder wall thickening in non-acute setting. It was developed based on a systematic review of the literature and the consensus of an international multidisciplinary committee comprising expert radiologists, gastroenterologists, gastrointestinal surgeons, surgical oncologists, medical oncologists, and pathologists using modified Delphi method. For risk stratification, the GB-RADS system recommends six categories (GB-RADS 0-5) of gallbladder wall thickening with gradually increasing risk of malignancy. GB-RADS is based on gallbladder wall features on US including symmetry and extent (focal vs. circumferential) of involvement, layered appearance, intramural features (including intramural cysts and echogenic foci), and interface with the liver. GB-RADS represents the first collaborative effort at risk stratifying the gallbladder wall thickening. This concept is in line with the other US-based risk stratification systems which have been shown to increase the accuracy of detection of malignant lesions and improve management.

Grayscale ultrasonography findings for characterization of gallbladder wall thickening in non-acute setting: a systematic review and meta-analysis

BACKGROUND

The accurate characterization of gallbladder wall thickening (GWT) into benign or malignant on ultrasound (US) is a significant challenge.

METHODS

We searched the MEDLINE and EMBASE databases for studies reporting two-dimensional grayscale US in benign and malignant GWT. The pooled prevalence was calculated using a generalized linear mixed method with a random-effects model. The pooled sensitivity and specificity were calculated using a bivariate random-effects model.

RESULTS

Of the 7309 studies screened by titles, 73 studies with 18,008 patients were included. The most common findings in xanthogranulomatous cholecystitis (XGC) were lack of wall disruption and intramural hypoechoic nodules while adenomyomatosis (ADM) was frequently associated with intramural cysts and intramural echogenic foci. Echogenic foci, lack of gallbladder wall disruption, and hypoechoic nodules had a sensitivity of 89%, 77%, and 66% and specificity of 86%, 51%, and 80%, respectively for the diagnosis of benign GWT. Focal thickening and indistinct liver interface had a sensitivity of 75% and 55% and specificity of 64% and 69%, respectively for the diagnosis of malignant GWT.

CONCLUSION

intramural features (echogenic foci, hypoechoic nodules), gallbladder wall disruption, and liver interface are useful US features for the characterization of GWT.

Imaging of gallbladder metastasis

Gallbladder metastasis (GM) is a rare condition, often with a late diagnosis or detected upon autopsy. There is no extensive literature on the imaging diagnosis of GM. Here we present a comprehensive review of the literature with the aim of helping to interpret the clinical findings and imaging features of such patients. Few studies on GM are reported in literature. GM by melanoma accounts for about 55.6% of cases. The remaining cases origin from breast cancer (13.6%), hepatocellular carcinoma (13.6%), renal cell carcinoma (6.8%), lung cancer (4.5%), lymphoma (3.5%) and gastric cancer (2.4%). The most common clinical presentation of GM is abdominal pain from cholecystitis due to obstruction of the cystic duct. The main ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI) findings that clinicians and radiologists should consider in their everyday medical activity were discussed. The diagnosis of GM was often achieved through a combination of more than one imaging modality. In more than 90% of cases, the diagnosis of GM is often late and combined with other organs involvement in the terminal stage of the malignancy. The knowledge of the clinical features and different imaging techniques through careful evaluation of the gallbladder can help to achieve early diagnosis and avoid misdiagnosis or false negative results.

Gallbladder Metastasis of Renal Cell Carcinoma: A Case Report

The gallbladder (GB) is a rare site of renal cell carcinoma (RCC) metastasis. To the best of our knowledge, only a few reports of CT findings of GB metastasis exist in the literature. Herein, we report a case of histologically proven GB metastasis of RCC in a 55-year-old male who underwent CT for an intraluminal polypoid mass simulating a primary GB lesion.

Key Imaging Findings for the Prospective Diagnosis of Rare Diseases of the Gallbladder and Cystic Duct

There are various diseases of the gallbladder and cystic duct, and imaging diagnosis is challenging for the rare among them. However, some rare diseases show characteristic imaging findings or patient history; therefore, familiarity with the imaging presentation of rare diseases may improve diagnostic accuracy and patient management. The purpose of this article is to describe the imaging findings of rare diseases of the gallbladder and cystic duct and identify their pathological correlations with these diseases.

Gallbladder polyps ultrasound: what the sonographer needs to know

Gallbladder polyps are protuberances of the gallbladder wall projecting into the lumen. They are usually incidentally found during abdominal sonography or diagnosed on histopathology of a surgery specimen, with an estimated prevalence of up to 9.5% of patients. Gallbladder polyps are not mobile and do not demonstrate posterior acoustic shadowing; they may be sessile or pedunculated. Gallbladder polyps may be divided into pseudopolyps and true polyps. Pseudopolyps are benign and include cholesterolosis, cholesterinic polyps, inflammatory polyps, and localised adenomyomatosis. True gallbladder polyps can be benign or malignant. Benign polyps are most commonly adenomas, while malignant polyps are adenocarcinomas and metastases. There are also rare types of benign and malignant true gallbladder polyps, including mesenchymal tumours and lymphomas. Ultrasound is the first-choice imaging method for the diagnosis of gallbladder polyps, representing an indispensable tool for ensuring appropriate management. It enables limitation of secondary level investigations and avoidance of unnecessary cholecystectomies.

Acute cholecystitis caused by gallbladder metastasis from non-small cell lung cancer: a case report

Although non-small cell lung cancer can metastasize to any part of the body, metastasis to the gallbladder is extremely rare. We present a case of acute cholecystitis caused by gallbladder metastasis from non-small cell lung cancer. A 66-year-old man diagnosed with primary stage IV T4N3M1b non-small cell lung cancer was admitted to our hospital to receive chemotherapy, during which he presented with right upper abdominal pain. Abdominal contrast-enhanced computed tomography showed an enhanced mass at the neck of the gallbladder and gallbladder distension with obvious wall thickening. Acute cholecystitis caused by obstruction of the gallbladder neck by malignancy was suspected. Open cholecystectomy, extrahepatic bile duct resection, and Roux-en-Y choledochojejunostomy were performed. Pathological and immunohistochemical examinations revealed gallbladder metastasis originating from non-small cell lung cancer. In conclusion, when a patient with lung cancer presents with acute cholecystitis, the rare possibility of gallbladder metastasis should be considered.

Gallbladder Carcinoma and Its Differential Diagnosis at MRI: What Radiologists Should Know

Gallbladder carcinoma is the most common cancer of the biliary system. It is challenging to diagnose because patients are often asymptomatic or present with nonspecific symptoms that mimic common benign diseases. Surgical excision is the only curative therapy and is best accomplished at early non-locally advanced stages. Unfortunately, gallbladder cancer often manifests at late locally advanced stages, precluding cure. Early tumors are often incidentally detected at imaging or at cholecystectomy performed for another indication. Typical imaging features of localized disease include asymmetric gallbladder wall thickening, polyps larger than 1.0 cm, and a solid mass replacing the gallbladder lumen. Advanced tumors are often infiltrative and can be confusing at CT and MRI owing to their large size. Determination of the origin of the lesion is paramount to narrow the differential diagnosis but is often challenging. It is important to identify gallbladder cancer and distinguish it from other benign and malignant hepatobiliary processes. Since surgical resection is the only curative treatment option, radiologist understanding and interpretation of pathways of nodal and infiltrative tumor spread can direct surgery or preclude patients who may not benefit from surgery. While both CT and MRI are effective, MRI provides superior soft-tissue characterization of the gallbladder and biliary tree and is a useful imaging tool for diagnosis, staging, and evaluation of treatment response. ^©RSNA, 2020.

Malignant metastatic melanoma to the gallbladder: Report of a peculiar case

INTRODUCTION

Melanoma is one of the most aggressive and one of the fastest growing types of cancer. The occurrence of a malignant melanoma in the gastrointestinal tract, either primary or metastatic, is a rare event. Metastatis from cutaneous malignant melanoma to the gallbladder are a highly uncommon finding, usually associated with diffuse metastatic disease and observed during autopsy. The event of a solitary metastasis of malignant melanoma to gallbladder is barely reported.

CASE REPORT

We report a case of a 35-year old Caucasian woman with isolated metastasis of gallbladder from cutaneous primary malignant melanoma managed with laparoscopic cholecystectomy.

DISCUSSION

Gallbladder metastasis as a first site of recurrence represents a rare condition for all cancers. Since the occurrence of an isolated gallbladder metastasis of cutaneous melanoma is an uncommon circumstance, no therapeutic guidelines have yet been proposed. Nevertheless cholecystectomy appears to be the standard of care for the treatment of this unusual condition, especially when symptomatic and for palliative purpose. The surgical approach is still debated, with no unanimous consent between mini-invasive surgery and open technique.

CONCLUSION

In our case, we decided to carry out a three-port laparoscopic cholecystectomy, preferring a mini-invasive approach considering the good performance status of our patient and her young age.

Colorectal metastasis to the gallbladder mimicking a primary gallbladder malignancy: histopathological and molecular characteristics

AIMS

Outcomes of colorectal cancer (CRC) treatment and survival have steadily improved during the past decades, accompanied by an increased risk of developing second primary tumours and metastatic tumours at unusual sites. Metastatic CRC can show mucosal colonisation, thereby mimicking a second primary tumour. This potential confusion could lead to incorrect diagnosis and consequently inadequate treatment of the patient. The aim of this study was to differentiate between metastatic CRC and a second primary (gallbladder cancer, GBC) using a combination of standard histopathology and molecular techniques.

METHODS AND RESULTS

Ten consecutive patients with both CRC and GBC were identified in our region using the Dutch National Pathology Archive (PALGA). Two patients served as negative controls. Histology of GBC was reviewed by nine pathologists. A combination of immunohistochemistry, microsatellite analysis, genomewide DNA copy number analysis and targeted somatic mutation analysis was used to aid in differential diagnosis. In two patients, CRC and GBC were clonally related, as confirmed by somatic mutation analysis. For one case, this was confirmed by genomewide DNA copy number analysis. However, in both cases, pathologists initially considered the GBC as a second primary tumour.

CONCLUSIONS

Metastatic CRC displaying mucosal colonisation is often misinterpreted as a second primary tumour. A combination of traditional histopathology and molecular techniques improves this interpretation, and lowers the risk of inadequate treatment.

Incidental metastases and lymphoma of the gallbladder - an analysis of ten rare cases identified from a large national database

Background: The aim was to identify and characterize rare malignancies of the gallbladder, incidentally found at cholecystectomy, and describe the diagnostic work-up, treatment and outcome. Methods: Data from cholecystectomies during 2007-2014 registered in the Swedish Register for Gallstone Surgery (GallRiks) were analyzed for incidental cancer. For completion of the pathology report, data were linked with the Swedish Registry for Cancer in the liver and biliary tract (SweLiv) and/or the Swedish Cancer Registry. Results: From 36,355 patients that underwent cholecystectomy on a benign indication 215 cases of incidental gallbladder cancer (IGBC) were identified. In total seven patients with metastases to the gallbladder from different primary tumors (breast cancer, malignant melanoma, gastric cancer, renal cell carcinoma, upper gastrointestinal cancer, colon cancer and pancreatic cancer) and three patients with lymphoma involvement of the gallbladder were found. Most patients were female with no difference between the groups (8/10 versus 171/215). The median age for the metastasis and lymphoma (MOL) group was equal to the IGBC group, 70 (64-72) years versus 70 (63-78) years. All patients in the MOL group underwent preoperative imaging with ultrasound or computed tomography, on which no metastases were identified. In only two patients a tumor was seen by the surgeon during the perioperative examination of the gallbladder. The median survival was 5.8 months for MOL patients and 23 months for IGBC patients. Conclusion: Metastases and lymphoma of the gallbladder are rare. Traditional imaging methods prior to cholecystectomy may miss gallbladder malignancies. A liberal approach of histopathological analysis of the gallbladder should be applied.

Metastatic Gallbladder Melanoma Presenting as Acute Emphysematous Cholecystitis

Malignant melanoma is an aggressive tumor with a high potential for distant metastases, including spread to the gallbladder where it represents more than half of all metastases detected at autopsy. Yet, it is rarely symptomatic in life and is a rare cause of acute cholecystitis. Emphysematous cholecystitis is a rare, potentially fatal variant of acute cholecystitis characterized by the presence of gas in the gallbladder lumen or wall. We report a 77-year-old woman with acute emphysematous cholecystitis as the initial feature of recurrent melanoma metastatic to the gallbladder. This exceptional association highlights the need to consider a relapse of malignancy when assessing unexplained abdominal symptoms in any patient with a prior history of melanoma.

Gallbladder carcinoma: causes of misdiagnosis at CT

Gallbladder carcinomas can present with varied imaging features on computed tomography. The three major imaging features include (1) focal or diffuse wall thickening with or without irregularity of the gallbladder; (2) polypoidal intraluminal mass; and (3) large mass obscuring and replacing the gallbladder, often extending to the liver. Patterns of wall thickening or polypoid growth are often confused with various benign gallbladder diseases due to overlap of imaging findings. Moreover, gallbladder carcinomas that coexist with benign gallbladder diseases make accurate preoperative diagnosis more difficult. Recently, high-resolution ultrasound (HRUS) has been regarded as a problem-solving tool for gallbladder diseases. In this article, we will illustrate various imaging presentations of gallbladder cancer, along with imaging pitfalls and recently updated HRUS findings.

CT findings of gallbladder metastases: emphasis on differences according to primary tumors

Objective

To describe computed tomography (CT) features of metastatic gallbladder (GB) tumors (MGTs) from various primary tumors and to determine whether there are differential imaging features of MGTs according to different primary tumors.

Materials and Methods

Twenty-one patients who had pathologically confirmed MGTs and underwent CT were retrospectively enrolled. Clinical findings including presenting symptoms, type of surgery, and interval between primary and metastatic tumors were recorded. Histologic features of primary tumor and MGTs including depth of invasion were also reviewed. Imaging findings were analyzed for the location and morphology of MGTs, pattern and degree of enhancement, depth of invasion, presence of intact overlying mucosa, and concordance between imaging features of primary and metastatic tumors. Significant differences between the histologies of MGTs and imaging features were determined.

Results

The most common primary tumor metastasized to the GB was gastric cancer (n = 8), followed by renal cell carcinoma (n = 4) and hepatocellular carcinoma (n = 3). All MGTs (n = 21) manifested as infiltrative wall thickenings (n = 15) or as polypoid lesions (n = 6) on CT, similar to the features of primary GB cancers. There were significant differences in the morphology of MGTs, enhancement pattern, enhancement degree, and depth of invasion according to the histology of primary tumors (p < 0.05). Metastatic adenocarcinomas of the GB manifested as infiltrative and persistently enhancing wall thickenings, while non-adenocarcinomatous metastases usually manifested as polypoid lesions with early wash-in and wash-out.

Conclusion

Although CT findings of MGTs are similar to those of primary GB cancer, they are significantly different between the various histologies of primary tumors.

Contrast enhanced ultrasound of a gallbladder lesion in a patient with a history of renal cell and rectal cancer

The gallbladder is an uncommon site of metastatic cancer. Although ultrasound can be regarded as a first line investigation for the detection of gallbladder lesions, differentiation between benign and malignant tumors usually requires resection. Real-time contrast enhanced ultrasound (CEUS) is a well-established technique for the classification of liver, pancreatic, and renal diseases (Weskott, 2008). The application of CEUS in the diagnosis of gallbladder tumors has rarely been described. We report the application of contrast enhanced ultrasound for the characterization of a gallbladder lesion in a 63-year-old patient with a history of renal cell and rectal cancer.

Gallbladder Metastasis of Non-small Cell Lung Cancer Presenting as Acute Cholecystitis

Although non-small cell lung cancer (NSCLC) can metastasize to almost any organ, metastasis to the gallbladder with significant clinical manifestation is relatively rare. Here, we report a case of gallbladder metastasis of NSCLC presenting as acute cholecystitis. A 79-year-old man presented with pain in the right upper quadrant and fever. A computed tomography (CT) scan of the chest and abdomen showed a cavitary mass in the right lower lobe of the lung and irregular wall thickening of the gallbladder. Open cholecystectomy and needle biopsy of the lung mass were performed. Histological examination of the gallbladder revealed a moderately-differentiated squamous cell carcinoma displaying the same morphology as the lung mass assessed by needle biopsy. Subsequent immunohistochemical examination of the gallbladder and lung tissue showed that the tumor cells were positive for P63 but negative for cytokeratin 7, cytokeratin 20 and thyroid transcription factor-1. A second primary tumor of the gallbladder was excluded by immunohistochemical methods, and the final pathological diagnosis was gallbladder metastasis of NSCLC. Although the incidence is extremely rare, acute cholecystitis can occur in association with lung cancer metastasis to the gallbladder.

Metastasis of the gallbladder in clear cell renal carcinoma

Metastasis of the gallbladder due to renal cell tumors is rare. We present a case of gallbladder and metachronous left adrenal metastasis at six months follow-up, which demonstrates the importance of radiological tests and histology when making a definitive diagnosis. Clinical findings are not specific enough to arrive at a final diagnosis. However, immunohistochemistry is necessary to differentiate between primary and secondary metastatic tumors. Cholecystectomy should be performed to obtain a definitive diagnosis and to improve survival in cases of single lesions in the gallbladder.