Cystic lesions of the liver. AJR Am J Roentgenol. 2011;196:W355-W366. [PMID: 21427297 DOI: 10.2214/ajr.10.5292]

Contrast-enhanced ultrasound in the characterization of complex cystic focal liver lesions

Complex cystic focal liver lesions (FLLs) found at non-contrast ultrasound (US) may turn out to be malignant. In this prospective, monocentric study we investigated the value of contrast-enhanced US (CEUS) in the differential diagnosis of complex cystic FLLs. In the past 3 years, all patients with complex cystic FLLs unclassifiable at US underwent CEUS with low-transmit insonation power. We evaluated 36 consecutive patients with 61 FLLs (1-6/patient, mean = 2). The diameter of the lesions ranged from 1.1 to 7.9 cm (mean = 3.9 cm). Sixteen patients had an extrahepatic malignancy. There were 42 malignant lesions and 19 benign lesions. No lesion had a certain diagnosis at conventional US, whereas 16 FLLs were classified as probable (benign or malignant) and 45 as uncertain. CEUS correctly categorized 95% of the malignant cases. CEUS was not able to differentiate the biliary cystadenoma from its malignant counterpart and misdiagnosed two abscesses. Complete non-enhancement throughout three phases or sustained enhancement in the portal/late phase was exhibited in most benign complex cystic FLLs, except for 1 (of the 3) cystadenomas and in 2 (of the 4) abscesses. On the other hand, all malignant lesions presented a contrast washout with a hypo-enhancing appearance. CEUS may provide added diagnostic value in all complex cystic FLLs found uncertain at conventional US, potentially avoiding the use of more invasive and expensive imaging modalities.

Benign liver lesions: grey-scale and contrast-enhanced ultrasound appearances

Ultrasound is often the first point of detection of liver lesions, with up to 75% of liver lesions detected at ultrasound having benign histology. In 2012, NICE issued recommendations that ultrasound contrast be used for the evaluation of incidentally discovered liver lesions. This has been demonstrated to provide a rapid and cost-effective evaluation for incidental liver lesions, in many cases precluding the need for further CT or MRI scans. The aim of this review is to demonstrate the ultrasound features of benign liver lesions, and to demonstrate their further characterisation with contrast ultrasound.

National trends in the use of surgery for benign hepatic tumors in the United States

BACKGROUND

The widespread use of diagnostic imaging has led to an increase in the incidence and diagnosis of benign liver tumors. The objective of this study was to define the overall use and temporal trends of operative procedures for benign liver tumors using a nationally representative cohort.

METHODS

All patients who underwent liver surgery for benign liver tumors between 2000 and 2011 were identified from the Nationwide Inpatient Sample database. Trends in annual volume of liver procedures were analyzed using the average annual percent change (AAPC) assessed by joinpoint analysis.

RESULTS

There were 2,489 open (94.5%) and 144 (5.5%) minimally invasive surgical (MIS) procedures. Partial hepatectomy accounted for 43.8% of all cases (n = 1,153). Surgery for patients with benign liver tumors increased from 156 in 2000 to 272 in 2011 (AAPC, 5.8%; 95% CI, 3.2-8.6%). There was decline in the relative use of open operative procedures from 98.1% in 2000 to 92.3% in 2011 (AAPC, -0.4%; 95% CI, -0.7 to -0.1%). In contrast, the proportion of MIS procedures increased from 1.9% in 2000 to 7.7% in 2011 (AAPC, 7.4%; 95% CI, 1.9-13.3%). The median duration of stay among all patients was 5 days (interquartile range, 4-7; 5 days [open] vs 3 days [MIS]; P < .001). Inpatient mortality was 0.6% (n = 15 [open] vs n = 0 [MIS]; P = .43) and did not change during the study period (P > .05).

CONCLUSION

Overall volume of surgical management of benign liver tumors has increased substantially over the past decade. There has been a relative shift away from open procedures toward MIS procedures.

Incidental extra-mammary findings in breast MRI

AIM

To investigate the frequency, distribution, and nature of incidental extra-mammary findings detected with breast MRI.

MATERIALS AND METHODS

Incidental findings were defined as unexpected lesions outside the breast, not previously known or suspected at the time of referral. Five hundred consecutive breast MRI studies performed from June 2010 to September 2012 were reviewed in this retrospective study for which the institutional review board granted approval and waived the requirement for informed consent. MRI findings were compared with subsequent diagnostic procedures in order to differentiate benign from malignant lesions.

RESULTS

One hundred and thirty-eight incidental findings were found in 107 of the 500 (21.4%) examined patients. The most common site was the liver (61/138; 44.2%), followed by the lung (24/138; 17.4%), mediastinum (22/138; 15.9%), pleural cavity (15/138; 10.9%), bone tissue (9/138; 6.5%), spleen (3/138; 2.2%), major pectoral muscle (3/138; 2.2%), and kidney (1/138; 0.7%). Twenty-five of the 138 (18.1%) incidental findings were confirmed to be malignant, whereas the remaining 113 (81.9%) were benign. Malignant findings were exclusively detected in patients with known breast carcinoma, whereas incidental findings in patients without a history of carcinoma were all benign. Twenty-five of 100 (24.8%) incidental findings among patients with history of breast cancer were malignant.

CONCLUSION

Although many of incidental findings were benign, some were malignant, altering the diagnostic work-up, staging, and treatment. Therefore, it is important to assess the entire field of view carefully for abnormalities when reviewing breast MRI studies.

Rare benign tumors of the liver: still rare?

Background

Benign liver tumors are common. They do not spread to other areas of the body, and they usually do not pose a serious health risk. In fact, in most cases, benign liver tumors are not diagnosed because patients are asymptomatic. When they are detected, it’s usually because the person has had medical imaging tests, such as an ultrasound (US), computed tomography (CT) scan, or magnetic resonance imaging (MRI), for another condition.

Materials and methods

A search of the literature was made using cancer literature and the PubMed, Scopus, and Web of Science (WOS) database for the following keywords: “hepatic benign tumors”, “hepatic cystic tumors”, “polycystic liver disease”, “liver macroregenerative nodules”, “hepatic mesenchymal hamartoma”, “hepatic angiomyolipoma”, “biliary cystadenoma”, and “nodular regenerative hyperplasia”.

Discussion and conclusion

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in some areas of the world; there is an increasing incidence worldwide. Approximately 750,000 new cases are reported per year. More than 75 % of cases occur in the Asia-Pacific region, largely in association with chronic hepatitis B virus (HBV) infection. The incidence of HCC is increasing in the USA and Europe because of the increased incidence of hepatitis C virus (HCV) infection. Unlike the liver HCC, benign tumors are less frequent. However, they represent a chapter always more interesting of liver disease. In fact, a careful differential diagnosis with the forms of malignant tumor is often required in such a way so as to direct the patient to the correct therapy. In conclusion, many of these tumors present with typical features in various imaging studies. On occasions, biopsies are required, and/or surgical removal is needed. In the majority of cases of benign hepatic tumors, no treatment is indicated. The main indication for treatment is the presence of significant clinical symptoms or suspicion of malignancy or fear of malignant transformation.

Intracystic concentrations of tumour markers for the diagnosis of cystic liver lesions

BACKGROUND

Imaging occasionally fails to differentiate hepatic simple cysts from malignant or premalignant mucinous cystic lesions such as biliary cystadenomas. Hepatic simple cysts can be treated conservatively, whereas malignant or premalignant cysts require complete resection. This study assessed the ability of intracystic tumour marker concentrations to differentiate these disease entities.

METHODS

Intracystic fluid was sampled in patients undergoing partial or complete resection of a cystic lesion of the liver. The indication for surgery in hepatic simple cysts was symptoms or suspicion of a biliary cystadenoma. Intracystic concentrations of carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 19-9 and tumour-associated glycoprotein (TAG) 72 were measured to assess the diagnostic accuracy of these tumour markers. Cut-off values were defined by receiver operating characteristic (ROC) curves.

RESULTS

The study population comprised 118 patients (94 women) with a median age of 59 years. There were 75 patients with hepatic simple cysts, 27 with mucinous cysts (19 biliary cystadenomas, 4 biliary cystadenocarcinomas, 4 intraductal papillary mucinous neoplasms of the bile duct) and 16 with miscellaneous cysts. Unlike CEA and CA19-9, a TAG-72 concentration of more than 25 units/ml differentiated hepatic simple cysts from mucinous cysts with a sensitivity and a specificity of 0·79 and 0·97 respectively. The area under the ROC curve was 0·98 for mucinous versus hepatic simple cysts.

CONCLUSION

The concentration of TAG-72 in cyst fluid accurately identified hepatic cysts that required complete resection.

Rare cystic liver lesions: A diagnostic and managing challenge

Cystic formations within the liver are a frequent finding among populations. Besides the common cystic lesions, like simple liver cysts, rare cystic liver lesions like cystadenocarcinoma should also be considered in the differential diagnosis. Thorough knowledge of each entity’s nature and course are key elements to successful treatment. Detailed search in PubMed, Cochrane Database, and international published literature regarding rare cystic liver lesions was carried out. In our research are included not only primary rare lesions like cystadenoma, hydatid cyst, and polycystic liver disease, but also secondary ones like metastasis from gastrointestinal stromal tumors lesions. Up-to date knowledge regarding diagnosis and management of rare cystic liver lesions is provided. A diagnostic and therapeutic algorithm is also proposed. The need for a multidisciplinary approach by a team including radiologists and surgeons familiar with liver cystic entities, diagnostic tools, and treatment modalities is stressed. Patients with cystic liver lesions must be carefully evaluated by a multidisciplinary team, in order to receive the most appropriate treatment, since many cystic liver lesions have a malignant potential and evolution.

Hepatic loss of miR-122 predisposes mice to hepatobiliary cyst and hepatocellular carcinoma upon diethylnitrosamine exposure

Loss of miR-122 causes chronic steatohepatitis and spontaneous hepatocellular carcinoma. However, the consequence of miR-122 deficiency on genotoxic stress-induced liver pathogenesis is poorly understood. Here, we investigated the impact of miR-122 depletion on liver pathobiology by treating liver-specific miR-122 knockout (LKO) mice with the hepatocarcinogen diethylnitrosamine (DEN). At 25 weeks post-DEN injection, all LKO mice developed CK-19-positive hepatobiliary cysts, which correlated with DEN-induced transcriptional activation of Cdc25a mediated through E2f1. Additionally, LKO livers were more fibrotic and vascular, and developed larger microscopic tumors, possibly due to elevation of the Axl oncogene, a receptor tyrosine kinase as a novel target of miR-122, and several protumorigenic miR-122 targets. At 35 weeks following DEN exposure, LKO mice exhibited a higher incidence of macroscopic liver tumors (71%) and cysts (86%) compared to a 21.4% and 0% incidence of tumors and cysts, respectively, in control mice. The tumors in LKO mice were bigger (ninefold, P = 0.015) and predominantly hepatocellular carcinoma, whereas control mice mostly developed hepatocellular adenoma. DEN treatment also reduced survival of LKO mice compared to control mice (P = 0.03). Interestingly, induction of oxidative stress and proinflammatory cytokines in LKO liver shortly after DEN exposure indicates predisposition of a pro-tumorigenic microenvironment. Collectively, miR-122 depletion facilitates cystogenesis and hepatocarcinogenesis in mice on DEN challenge by up-regulating several genes involved in proliferation, growth factor signaling, neovascularization, and metastasis.

Current management of noninfectious hepatic cystic lesions: A review of the literature

Nonparasitic hepatic cysts consist of a heterogeneous group of disorders, which differ in etiology, prevalence, and manifestations. With improving diagnostic techniques, hepatic cysts are becoming more common. Recent advancements in minimally invasive technology created a new Era in the management of hepatic cystic disease. Herein, the most current recommendations for management of noninfectious hepatic cysts are described, thereby discussing differential diagnosis, new therapeutic modalities and outcomes.

Pathophysiology, epidemiology, classification and treatment options for polycystic liver diseases

Polycystic liver diseases (PLD) represent a group of genetic disorders in which cysts occur in the liver (autosomal dominant polycystic liver disease) or in combination with cysts in the kidneys (autosomal dominant polycystic kidney disease). Regardless of the genetic mutations, the natural history of these disorders is alike. The natural history of PLD is characterized by a continuous increase in the volume and the number of cysts. Both genders are affected; however, women have a higher prevalence. Most patients with PLD are asymptomatic and can be managed conservatively. Severe symptoms can affect 20% of patients who develop massive hepatomegaly with compression of the surrounding organs. Rrarely, patients with PLD suffer from acute complications caused by the torsion of hepatic cysts, intraluminal cystic hemorrhage and infections. The most common methods for the diagnosis of PLD are cross sectional imaging studies. Abdominal ultrasound and computerized tomography are the two most frequently used investigations. Magnetic resonance imaging is more sensitive and specific, and it is a valuable test for patients with intravenous contrast allergies or renal dysfunction. Different treatment modalities are available to physicians caring for these patients. Medical treatment has been ineffective. Percutaneous sclerotherapy, trans-arterial embolization, cyst fenestration, hepatic resection and liver transplantation are indicated to specific groups of patients and have to be tailored according to the extent of disease. This review outlines the current knowledge of the pathophysiology, clinical course, diagnosis and treatment strategies of PLD.

Evaluation of hepatic cystic lesions

Hepatic cysts are increasingly found as a mere coincidence on abdominal imaging techniques, such as ultrasonography (USG), computed tomography (CT) and magnetic resonance imaging (MRI). These cysts often present a diagnostic challenge. Therefore, we performed a review of the recent literature and developed an evidence-based diagnostic algorithm to guide clinicians in characterising these lesions. Simple cysts are the most common cystic liver disease, and diagnosis is based on typical USG characteristics. Serodiagnostic tests and microbubble contrast-enhanced ultrasound (CEUS) are invaluable in differentiating complicated cysts, echinococcosis and cystadenoma/cystadenocarcinoma when USG, CT and MRI show ambiguous findings. Therefore, serodiagnostic tests and CEUS reduce the need for invasive procedures. Polycystic liver disease (PLD) is arbitrarily defined as the presence of > 20 liver cysts and can present as two distinct genetic disorders: autosomal dominant polycystic kidney disease (ADPKD) and autosomal dominant polycystic liver disease (PCLD). Although genetic testing for ADPKD and PCLD is possible, it is rarely performed because it does not affect the therapeutic management of PLD. USG screening of the liver and both kidneys combined with extensive family history taking are the cornerstone of diagnostic decision making in PLD. In conclusion, an amalgamation of these recent advances results in a diagnostic algorithm that facilitates evidence-based clinical decision making.

Hepatobiliary anomalies associated with ABCB4/MDR3 deficiency in adults: a pictorial essay

BACKGROUND

ABCB4/MDR3 gene variants are mostly associated with a peculiar form of cholelithiasis in European adults, currently referred to as low phospholipid-associated cholelithiasis (LPAC) syndrome.

METHODS

LPAC syndrome is a rare genetic disorder, characterised by the following clinical features: biliary symptoms before the age of 40, recurrence of the symptoms after cholecystectomy, and intrahepatic microlithiasis or intrahepatic hyperechogenic foci.

RESULTS

Imaging features associated with ABCB4/MDR3 mutations are not specific and correspond to a wide spectrum of biliary abnormalities. The main feature is the presence of intrahepatic lithiasis. Other uncommon presentations have been described, such as uni- or multifocal spindle-shaped dilatations of the intrahepatic bile ducts filled with gallstones, secondary sclerosing cholangitis, biliary cirrhosis, and intrahepatic cholangiocarcinoma.

CONCLUSION

This review focuses on MR features related to ABCB4/MDR3 mutations.

MAIN MESSAGES

• LPAC syndrome is characterised by intrahepatic microlithiasis or intrahepatic hyperechogenic foci. • Ultrasound examination is very accurate in detecting intrahepatic stones. • At MR imaging, LPAC syndrome is associated with various presentations.

Multicystic hepatocarcinoma mimicking liver abscess

The diagnosis of hepatocellular carcinoma (HCC) became easier in relation to the improved radiological examinations; however, the neoplasm may occur under atypical presentations mimicking other benign or malignant processes. Multicystic HCC mimicking a liver abscess associated with septic-type fever and leukocytosis is rare, has a poor prognosis, and poses diagnostic and therapeutic dilemmas. We present the case of an 80-year-old patient, who presented with fever, leukocytosis, and large cystic masses involving right and left lobes of the liver initially considered abscesses and finally diagnosed as HCC after open drainage and liver biopsy. Although the patient died on the tenth postoperative day due to pulmonary oedema, the authors emphasize the high index of suspicion needed in the diagnosis of this unusual presentation of HCC.

Giant hepatic cyst with septal structure: diagnosis and management

The hepatic cyst is a common benign liver tumor, and no surgical treatment is necessary. However, it is difficult to correctly diagnose the giant hepatic cyst containing the solid septal structures inside, from the malignant cystadenocarcinomas. The various imaging modalities such as computed tomography, magnetic resonance imaging, and ultrasonography, have been developed and are useful for the diagnosis of these liver tumors. Reviewing the other reports in this paper, the combination of more than 2 modalities will help to diagnose these tumors; however, the malignant potential is unable to be excluded if the tumor is huge. Therefore, the surgical resection should be considered for the huge hepatic cysts with septal structures if the correct diagnosis is unable to be made. For example, when the hemorrhages cause the granulation in the septa which often shows neovascularization, the imaging modalities are unable to define this situation from the malignant tissue with hypervascularity. Therefore, with the careful review of other reports, we conclude that if the imaging studies show the possible malignant potential or the sizing-up is marked, the surgical treatment should be considered with the consent from the patients.