Indeterminate Liver Research Articles

Combining CEUS and CT/MRI LI-RADS major imaging features: diagnostic accuracy for classification of indeterminate liver observations in patients at risk for HCC.

To determine the diagnostic accuracy of combining CEUS and CT/MRI LI-RADS major imaging features for the improved categorization of liver observations indeterminate on both CT/MRI and CEUS. A retrospective analysis using a database from a prospective study conducted at 11 centers in North America and Europe from 2018 to 2022 included a total of 109 participants at risk for HCC who had liver observations with indeterminate characterization (LR3, LR-4, and LR-M) on both CEUS and CT/MRI. The individual CEUS and CT/MRI LI-RADS major features were extracted from the original study and analyzed in various combinations. Reference standards included biopsy, explant histology, and follow-up CT/MRI. The diagnostic performance of the combinations of LI-RADS major features for definitive diagnosis of HCC was calculated. A reverse, stepwise logistical regression sub-analysis was also performed. This study included 114 observations indeterminate on both CT/MRI and CEUS. These observations were categorized as LR-3 (n = 37), LR-4 (n = 41), and LR-M (n = 36) on CT/MRI and LR-3 (n = 48), LR-4 (n = 36), LR-M (n = 29), and LR-TIV (n = 1) on CEUS. Of them, 43.0% (49/114) were confirmed as HCC, 37.3% (43/114) non-malignant, and 19.3% (22/114) non-hepatocellular malignancies. The highest diagnostic accuracy among the combinations of imaging features was achieved in CT/MRI LR-3 observations, where the combination of CEUS arterial phase hyper-enhancement (APHE) + CT/MRI APHE had 96.7% specificity, 75.0% positive predictive value (PPV), and 86.5% accuracy for HCC. The combination of LI-RADS major features on CT/MRI and CEUS showed higher specificity, PPV, and accuracy compared to individual modalities' assessments, particularly for CT/MRI LR-3 observations.

Risk of Malignancy in Indeterminate Liver Nodules Among Patients with Cirrhosis: A Retrospective Cohort Study

BackgroundSeveral studies have shown a higher risk of liver cancer from indeterminate liver nodules, but the exact occurrence and predictors of liver cancer in this group are still unclear. Our aim is to study the development of liver cancer in this population and identify any potential risk factors.MethodsThis retrospective study evaluated cirrhotic patients with indeterminate liver nodules from 2013 to 2023.Data from electronic patient records was analyzed to assess the association between HCC and baseline factors. Subgroup exploratory analysis compared characteristics of patients with de novo HCC and those with nodule transformation HCC.ResultsOut of 116 patients with liver nodules, 19 (16%) developed HCC in up to 7.5-year follow-up. Univariate Cox regression analysis showed a significant association between HCC incidence and smoking [hazard ratio (HR) 2.60, 95% Confidence Interval [CI] 1.01–6.74), nodule diameter exceeding 2 cm (HR 5.41, 95% CI 1.45–20.18), and baseline LI-RADS score 3 (HR 3.78, 95% CI 1.36–19.52). Multivariate Cox regression analysis revealed significant independent associations with nodule diameters 1 cm to < 2 cm (adjusted HR 3.35, 95% CI 1.06–10.60) and greater than 2 cm (adjusted HR 5.85, 95% CI 1.10–31.16), as well as with LI-RADS 3 lesions (adjusted HR 3.75, 95% CI 1.16–12.11) with adjusting other potential predictors and covariates.ConclusionOur findings show a higher incidence of HCC in patients with indeterminate liver nodules, increasing over time and reaching 30% at seven years. Nodules larger than 1–2 cm or LI-RADS 3 lesions pose increased risk for HCC. Enhanced surveillance is necessary given the lack of clear management guidelines.

The utility of next-generation sequencing in challenging liver FNA biopsies.

Fine-needle aspiration (FNA) biopsy is increasingly used for the diagnosis of hepatocellular masses. Because distinguishing well differentiated hepatocellular carcinoma (HCC) from other well differentiated hepatocellular lesions (e.g., large regenerative nodules or focal nodular hyperplasia) requires an assessment of architectural features, this may be challenging on FNA when intact tissue fragments are not sampled. Poorly differentiated HCC and intrahepatic cholangiocarcinoma (ICC) may exhibit overlapping pathologic features. Molecular testing can be helpful, because mutations in TERT promoter and CTNNB1 (β-catenin) are characteristic of HCC, whereas mutations in BAP1, IDH1/IDH2, and PBRM1 may favor ICC. The goal of this study was to assess the role of next-generation sequencing (NGS) in further subclassifying indeterminate liver lesions sampled by FNA. A retrospective review of liver cytology cases with NGS on cell block material was performed. Age, radiologic features, background hepatic disease and treatment, outcome, and NGS data were obtained from the electronic medical record. Twelve FNA biopsies that had cell blocks from clinically suspected primary hepatic masses were identified. The presence of a TERT promoter mutation supported a diagnosis of HCC for one well differentiated neoplasm. For three patients, the presence of mutations, such as IDH1, CDKN2A/CDKN2B, and BRAF, supported a diagnosis of ICC. Of the eight poorly differentiated carcinomas, NGS helped refine the diagnosis in six of eight cases, with one HCC, three ICCs, and two that had combined HCC-ICC, with two cases remaining unclassified. Molecular diagnostics can be helpful to distinguish HCC and ICC on FNA specimens, although a subset of primary hepatic tumors may remain unclassifiable.

Natural History of Indeterminate Liver Nodules in Patients With Advanced Liver Disease: A Multicenter Retrospective Cohort Study.

Indeterminate liver nodules (ILNs) are frequently encountered on diagnostic imaging after positive hepatocellular carcinoma (HCC) surveillance results, but their natural history remains unclear. We conducted a multicenter retrospective cohort study among patients with ≥1 newly detected LI-RADS 3 (LR-3) lesion ≥1 cm or LI-RADS 4 (LR-4) lesion of any size (per LI-RADS v2018) between January 2018 and December 2019. Patients were followed with repeat imaging at each site per institutional standard of care. Multivariable Fine-Gray models were used to evaluate associations between potential risk factors and patient-level time-to-HCC diagnosis, with death and liver transplantation as competing risks. Of 307 patients with ILNs, 208 had LR-3 lesions, 83 had LR-4 lesions, and 16 had both LR-3 and LR-4 lesions. HCC incidence rates for patients with LR-3 and LR-4 lesions were 110 (95% CI 70-150) and 420 (95% CI 310-560) per 1,000 person-year, respectively. In multivariable analysis, incident HCC among patients with LR-3 lesions was associated with older age, thrombocytopenia (platelet count ≤150 ×10 9 /L), and elevated serum alpha-fetoprotein levels. Among those with LR-4 lesions, incident HCC was associated with a maximum lesion diameter >1 cm. Although most patients had follow-up computed tomography or magnetic resonance imaging, 13.7% had no follow-up imaging and another 14.3% had follow-up ultrasound only. ILNs have a high but variable risk of HCC, with 4-fold higher risk in patients with LR-4 lesions than those with LR-3 lesions, highlighting a need for accurate risk stratification tools and close follow-up in this population.

Radiologic Occult Metastases in Pancreatic Cancer: Analysis of Risk Factors and Survival Outcomes in the Age of Contemporary Neoadjuvant Multi-agent Chemotherapy.

Radiologic occult metastatic disease (ROMD) in patients with pancreatic ductal adenocarcinoma (PDAC) who undergo contemporary neoadjuvant chemotherapy (NAC) has not been well studied. This study sought to analyze the incidence, risk factors, and oncologic outcomes for patients who underwent the NAC approach for PDAC. A retrospective review analyzed a prospectively maintained database of patients who had potentially resectable PDAC treated with NAC and were offered pancreatectomy at our institution from 2011 to 2022. Multivariable regression analysis was performed to assess risk factors associated with ROMD. Kaplan-Meier curves with log-rank analyses were generated to estimate time-to-event end points. The study enrolled 366 patients. Upfront and borderline resectable anatomic staging comprised 80% of the cohort, whereas 20% had locally advanced disease. The most common NAC regimen was FOLFIRINOX (n = 274, 75%). For 55 patients (15%) who harbored ROMD, the most common site was liver-only metastases (n = 33, 60%). The independent risk factors for ROMD were increasing CA19-9 levels during NAC (odds ratio [OR], 7.01; confidence interval [CI], 1.97-24.96; p = 0.008), indeterminate liver lesions (OR, 2.19; CI, 1.09-4.39; p = 0.028), and enlarged para-aortic lymph nodes (OR, 6.87; CI, 2.07-22.74; p = 0.002) on preoperative cross-sectional imaging. Receipt of palliative chemotherapy (p < 0.001) and eventual formal pancreatectomy (p = 0.04) were associated with survival benefit in the log-rank analysis. The median overall survival (OS) of the patients with ROMD was nearly 15 months from the initial diagnosis, with radiologic evidence of metastases occurring after a median of 2 months. Radiologic occult metastatic disease remains a clinical challenge associated with poor outcomes for patients who have PDAC treated with multi-agent NAC.

Utilization of Contrast-Enhanced Ultrasound in Diagnosis of Focal Liver Lesions.

Background and aims: Focal liver lesions (FLL) are one of the most common indications for hepatology and hepatobiliary surgery consultation. In this retrospective study, we aim to assess if contrast-enhanced ultrasound (CEUS) can address diagnostic dilemmas in the evaluation of indeterminate liver lesions by identifying characteristics of indeterminate FLL on CEUS and correlating these with cross-sectional imaging and pathology findings. Methods: We retrospectively reviewed all patients who underwent CEUS evaluation for liver lesions over a 28-month period (Oct 2020 to Jan 2023) at the University of Kentucky. To assess the relationship between CEUS results and the corresponding CT, MRI, and/or pathologic findings, the McNemar-Bowker tests were performed. Results: Twenty-nine patients were included (after two exclusions from a total n of 31). Mean age was 54 years, 62% were female, and 48% had underlying cirrhosis. Of the 29 patients with initial cross-sectional imaging, the initial results showed malignancy or likely malignant lesion in 6 patients and benign or likely benign lesion in 6 patients. The remaining 17 patients had inconclusive/indeterminate results. CEUS clarified an "indeterminate" CT/MRI result 15 times out of 17 (88.2%), moving the diagnosis to "benign" 11 times while suggesting "malignant" only four times. When aggregating indeterminate cross-sectional results with either benign or malignant categories suggested by CEUS, CEUS never reversed a benign CT/MRI diagnosis but often reversed a malignant CT/MRI diagnosis. Conclusion: CEUS provided a definitive diagnosis of indeterminate liver lesions in approximately 90% of patients and avoided the need for biopsy in most patients. In cases where the liver lesions were biopsied, CEUS accurately distinguished malignant versus benign lesions as confirmed by biopsy findings. CEUS, therefore, has the potential to provide a precise diagnosis for the majority of indeterminate lesions.

Diagnosis and management of indeterminate liver nodules in patients with cirrhosis.

Diagnosis and management of indeterminate liver nodules in patients with cirrhosis.

Augmenting care in hepatocellular carcinoma with artificial intelligence

Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer-related death worldwide and prognosis remains poor. The recent paradigm shifts in management algorithms of such patients have resulted in unique challenges in the early identification of HCC, prognosis, surgical outcomes, prioritization of potential transplant recipients, donor-recipient matching, and so on. In recent years, advancements in artificial intelligence (AI) capabilities have shown potential in HCC treatment. In this narrative review, we outline first the different types of AI models that are applied in clinical practice and then focus on the frontiers of AI research in the diagnosis, prognostication, and treatment of HCC, particularly in classification of indeterminate liver lesions, tumor staging, survival prediction, improving equity in transplant recipient selection, prediction of treatment response and prognosis. We show that US coupled with AI-driven predictive models can provide accurate noninvasive screening tools for early disease. While AI models applied to contrast-enhanced CT, MRI and PET studies may appear to have limited clinical utility in disease diagnosis and differentials, owing to their accuracy, we highlighted the importance of such models in predicting pathological findings preoperatively. Despite the availability of many accurate, sensitive, and specific AI algorithms that outperform traditional scoring systems, they have not been widely used in clinical practice. The challenges in AI application, including distributional shift and imbalanced data, lack of standardization, and the ‘black box’ phenomenon, are addressed here. The importance of AI in the future of HCC makes it important for clinicians to have a good understanding of different AI techniques, their benefits, and potential pitfalls.

A review of the indeterminate liver lesions on staging CT in patients with rectal cancer

A review of the indeterminate liver lesions on staging CT in patients with rectal cancer

954 Sarcoidosis Mimicking Progression of Melanoma: A Case Report

Abstract A 78-year-old lady with a history of malignant melanoma on the dorsal aspect of her left foot, presented with a new fluorodeoxyglucose positron emission tomography (FDG-PET) avid lesion in her left fibular head. The patient had been diagnosed eight months previously with a 5.1mm Breslow thickness invasive melanoma. Following initial diagnosis, she underwent a wide local excision and sentinel lymph node biopsy (SLN). The melanoma was completely excised and SLN was negative for malignancy. Postoperatively, she underwent radiological staging with computed tomography scans (CT) of her thorax, abdomen, and pelvis. This showed scattered pulmonary nodules, and multiple indeterminate liver lesions. A PET scan was then performed, which showed an expansile, FDG-avid, lytic lesion in the left fibular head, suspicious for bone metastasis. Following discussion at the multidisciplinary team meeting, the patient underwent an open biopsy of the fibular head. Histology revealed non-necrotising epitheloid granulomata without evidence of malignancy. Ziehl-Neelsen and periodic acid Schiff stains were negative. The findings were suggestive of sarcoidosis. The patient revealed she had a previous diagnosis of pulmonary sarcoidosis 25 years prior, however, had no known extrapulmonary disease and was not attending a specialist. The pulmonary findings on CT were consistent with sarcoidosis. Sarcoidosis is a systemic inflammatory disease characterised by the development of non-caseating granulomata which typically affect the lungs and lymph nodes but can affect multiple organ systems. This case highlights the diagnostic uncertainty of an FDG-avid lesion on PET, necessitating diagnostic biopsy. Sarcoidosis is an uncommon but possible differential in this setting.

Routine contrast-enhanced CT is insufficient for TNM-staging of duodenal adenocarcinoma

PurposeAdequate TNM-staging is important to determine prognosis and treatment planning of duodenal adenocarcinoma. Although current guidelines advise contrast-enhanced CT (CECT) for staging of duodenal adenocarcinoma, literature about diagnostic tests is sparse.MethodsIn this retrospective single-center cohort study, we analyzed the real life performance of routine CECT for TNM-staging and the assessment of resectability of duodenal adenocarcinoma. Intraoperative findings and pathological staging served as reference standard for resectability, T-, and N-staging. Biopsies, 18FDG-PET-CT, and follow-up were used as the reference standard for M-staging.ResultsFifty-two consecutive patients with duodenal adenocarcinoma were included, 26 patients underwent resection. Half of the tumors were isodense to normal duodenum on CECT. The tumor was initially missed in 7/52 patients (13%) on CECT. The correct T-stage was assigned with CECT in 14/26 patients (54%), N-stage in 11/26 (42%), and the M-stage in 42/52 (81%). T-stage was underestimated in (27%). The sensitivity for detecting lymph node metastases was only 24%, specificity was 78%. Seventeen percent of patients had indeterminate liver or lung lesions on CECT. Surgery with curative intent was started in 32 patients, but six patients (19%) could not be resected due to unexpected local invasion or metastases.ConclusionRadiologists and clinicians have to be aware that routine CECT is insufficient for staging and determining resectability in patients with duodenal adenocarcinoma. CECT underestimates T-stage and N-stage, and M-stage is often unclear, resulting in futile surgery in 19% of patients. Alternative strategies are required to improve staging of duodenal adenocarcinoma. We propose to combine multiphase hypotonic duodenography CT with MRI.

Clinical Outcomes of Patients With Suspicious (LI-RADS 4) Liver Observations

Hepatocellular cancer (HCC) surveillance is associated with increased curative treatment and improved survival, underscoring its importance in patients with cirrhosis.1 Surveillance is 1 step in a larger HCC screening continuum, and those with abnormal screening results must undergo diagnostic evaluation with multiphase computed tomography (CT) or magnetic resonance imaging (MRI).2 The Liver Imaging Reporting and Data System (LI-RADS) classifies liver observations in at-risk patients based on risk of malignancy and HCC, with LR-5 observations having a positive predictive value exceeding 95% for HCC. However, indeterminate liver nodules (ie, LR-3 or LR-4) are commonly observed in clinical practice, associated with heterogenous HCC risk, and have large variations in practice management.3,4 We previously reported the natural history of LR-3 observations in a multicenter cohort of patients with cirrhosis, demonstrating a high annual incidence for HCC development of 8.4 cases per 100 person-years;5 however, the natural history of LR-4 observations remains uncertain. Herein, we aimed to characterize clinical outcomes in patients with LR-4 observations in a multicenter cohort.

The fate of indeterminate liver lesions: What proportion are precursors of hepatocellular carcinoma?

BackgroundThe natural history and incidence of hepatocellular carcinoma (HCC) arising from indeterminate liver lesions are not well described. We aimed to define the incidence of HCC in a cohort of patients undergoing surveillance by magnetic resonance imaging (MRI) and estimate any associations with incident HCC.MethodsWe performed a retrospective follow-up study, identifying MRI scans in which indeterminate lesions had been reported between January 2006 and January 2017. Subsequent MRI scan reports were reviewed for incident HCC arising from indeterminate lesions, data were extracted from electronic patient records and survival analysis performed to estimate associations with baseline factors.ResultsOne hundred and nine patients with indeterminate lesions on MRI were identified. HCC developed in 19 (17%) patients over mean follow up of 4.6 years. Univariate Cox proportional hazards analysis found incident HCC to be significantly associated with baseline low platelet count (hazard ratio (HR) = 7.3 (95% confidence intervals (CI) 2.1–24.9), high serum alpha-fetoprotein level (HR = 2.7 (95% CI 1.0–7.1)) and alcohol consumption above fourteen units weekly (HR = 3.1 (95% CI 1.1–8.7)). Multivariate analysis, however, found that only low platelet count was independently associated with HCC (HR = 5.5 (95% CI 0.6–5.1)).ConclusionsHCC arises in approximately one fifth of indeterminate liver lesions over 4.6 years and is associated with a low platelet count at the time of first diagnosis of an indeterminate lesion. Incidence of HCC was more common in people with viral hepatitis and in those consuming > 14 units of alcohol per week. Our data may be used to support a strategy of enhanced surveillance in patients with indeterminate lesions.

P-L01 Newly detected liver nodules with a history of colorectal cancer: are they metastasis?

Abstract Background The diagnosis of newly detected liver nodules in patients with colorectal cancer (CRC) is crucial for determining prognosis and treatment. Accurate identification of benign nodules can help avoid unnecessary therapy. The aim of our study was to retrospectively review CRC patients who underwent liver resection for newly detected liver nodules in our institution. Methods We went over all patients with a history of CRC, who underwent liver resection from January 2012 to December 2019 in our institution. We specifically focused on nodules pathologically confirmed benign. Clinicopathological characteristics of these patients were collected. Results From 2012 to 2019, a total of 2632 CRC patients received liver resection for liver nodules, among which 2584 cases were proved to be malignant, and 48 cases were benign. Among these 48 cases, 24 were pathologically confirmed as focal nodular hyperplasia (FNH), 10 were inflammatory lesions, 9 were peliosis, and 5 were hemangioma. At least one pre-operative imaging examination (MRI, US, or PET-CT) indicated CRLM, while no one underwent gadoxetic acid-enhanced MRI. The median size of nodule was 2.0 cm (range, 0.4-8.0 cm). For therapy, ten patients received laparoscopic surgery, and 38 patients received open surgery; ten patients received chemotherapy after discovery of liver nodules. Conclusions Newly detected liver nodules with a history of colorectal cancer could be benign. Gadoxetic acid-enhanced MRI should be considered especially for indeterminate liver nodules that would be mimicker of colorectal cancer liver metastasis.

Hybrid Imaging with SPECT-CT and SPECT-MR in Hepatic Splenosis.

Splenosis, commonly occurs incidentally and locates to bowel surfaces, parietal peritoneum, mesentery, and diaphragm, but can potentially occur anywhere in the peritoneal cavity. Patients frequently have a history of splenectomy or trauma. On the other hand, hepatic splenosis is a rare entity and may present itself clinically. Indeterminate liver lesions can pose a clinical dilemma and may lead to additional investigations, anxiety, follow-up imaging and even to invasive procedures. MRI usually performs extremely well. In difficult cases, scintigraphy can be of great value -especially with novel SPECT-CT and SPECT-MR techniques-. We describe a case of a 29-year-old lady with hepatic splenosis and the impact of hybrid imaging.

Hepatobiliary and Pancreatic: Liver lesions in cirrhosis: When to biopsy?

A 70-year-old man originally from Poland was referred to the hepatoma service for investigation of two liver lesions found during routine hepatocellular carcinoma (HCC) screening. Active medical history included both castrate sensitive metastatic prostate cancer and Child–Pugh A cirrhosis secondary to type 2 diabetes mellitus and previous heavy alcohol use. For his prostate cancer, he was treated with androgen deprivation therapy (ADT) with goserelin and received upfront docetaxel chemotherapy with prednisolone, before being enrolled on a clinical trial of enzalutamide. Prostate specific antigen (PSA) level remained suppressed at <0.01 μg/L on therapy. The patient was asymptomatic with no features of hepatic decompensation. His Child–Pugh status was A6. Biochemistry revealed preserved synthetic liver function; alpha fetoprotein (AFP) level was 5 μg/L. Computed tomography (CT) chest, abdomen, and pelvis demonstrated two 10-mm arterially enhancing hepatic nodules in segments 7/8 and 4a (Fig. 1a) with no portal venous washout (Fig. 1b). On magnetic resonance imaging (MRI) with Primovist, both lesions retained Primovist and hence both were indeterminate (Liver Imaging Reporting and Data System [LI-RADS]-3). Differentials at discussion at the Hepatoma Multidisciplinary meeting included regenerative or dysplastic nodules, given metastatic prostate cancer typically shows hypodensity on contrast-enhanced imaging. The nodules were followed up in tandem with the patient's prostate cancer at 6 monthly intervals and were stable on contrast-enhanced CT (LI-RADS 3) at 12 and 18 months (Fig. 1c) (LI-RADS 3) and therefore did not meet criteria for biopsy. In addition, there were numerous new pulmonary nodules. At 24 months however, CT revealed new lesions concerning for multifocal HCC (Fig. 1d), increase in the size of the segment 7 and 8 lesions with a new 1.5-cm lesion in segment 2 with washout (LI-RADS 5). The patient remained clinically stable and had a suppressed PSA level. He underwent an ultrasound guided biopsy of the segment 2 lesion. Histopathology was consistent with a diagnosis of metastatic small cell neuroendocrine carcinoma. The patient was commenced on single agent Carboplatin to treat his now de-differentiated small cell prostate cancer, to which he has responded well with interval response demonstrated on serial CT of pulmonary and liver lesions in addition to the bony disease on CT SPECT. The diagnosis of HCC is typically made on cross-sectional radiological findings without the need for confirmatory tissue in cirrhotics. LI-RADS scoring system has high sensitivity and specificity in diagnosing HCC in cirrhotic patients and is applicable to lesions ≥ 1 cm. Thus, biopsy is rarely required to diagnose HCC. Current guidelines support the use of the LI-RADS as a classification system for reporting liver lesions. The decision to biopsy is a contentious clinical question that is not definitively answered by current guidelines. Biopsy carries known risks of bleeding, tumor seeding, and failure to obtain adequate tissue for sampling. There are several mimics of HCC on imaging. Intrahepatic cholangiocarcinomas are known to mimic HCC. Tumors such as neuroendocrine tumors, squamous cell carcinoma metastases, and lung cancer metastases require pathological differentiation from HCC. Prostate cancer metastasis to the liver is heralded by hypoenhancement on contrast-enhanced imaging, whereas small cell prostate cancer itself is ill defined in imaging and there is currently a paucity of literature describing its imaging characteristics. It is aggressive in nature and 40–50% of cases are reported to occur in men with pre-existing prostate adenocarcinoma. The PSA is highly sensitive to progression of metastatic prostate adenocarcinoma but not to de-differentiated carcinoma, and it can therefore be difficult to differentiate de-differentiated prostate cancer from HCC in the cirrhotic patient. This case demonstrates that although current clinical practice guidelines deliver a safe approach to the diagnosis of HCC, alternative diagnoses can be missed if they carry similar characteristics on cross-sectional imaging, especially in cirrhotic patients and particularly in those with a cancer history. The role of biopsy in indeterminate liver lesions is often a discussion point and requires multidisciplinary team discussion, and the LI-RADS criteria should always be interpreted in the clinical context.

Indeterminate liver lesions on gadoxetic acid-enhanced magnetic resonance imaging of the liver: Case-based radiologic-pathologic review

Different histopathological manifestations of focal liver lesions show varying common and uncommon imaging findings and some pathologies may show similar appearance despite of different histopathology. It is necessary to characterise focal liver lesions accurately as not only benign and malignant lesions are managed differently, but also certain benign lesions have differing management. These lesions are increasingly being detected due to rapid growth of use of cross-sectional imaging as well as improvement in image quality and new imaging techniques. Contrast enhanced magnetic resonance imaging (MRI) is considered the gold standard technique in characterising focal liver lesions. Addition of gadoxetic acid has been shown to significantly increase diagnostic accuracy in the detection and characterization of liver abnormalities. Classic imaging characteristics of common liver lesions, including their behaviour on gadoxetic acid enhanced MRI, have been described in literature over recent years. It is important to be familiar with the typical aspects of these lesions as well as know the uncommon and overlapping imaging features to reach an accurate diagnosis. In this article, we will review the well-described characteristic imaging findings of common and rare focal liver lesions and present several challenging cases encountered in the clinical setting, namely hepatocellular adenoma, focal nodular hyperplasia, hepatic angiomyolipoma, hepatocellular carcinoma, intrahepatic cholangiocarcinoma, neuroendocrine tumours as well as a pleomorphic liposarcoma of the liver.

Indeterminate Liver Lesions in Patients With Early Stage Rectal Cancer: Can They Be Ignored?

PurposeSmall, hypoattenuating, indeterminate liver lesions are often encountered during staging computed tomography (CT) in patients with early-stage rectal cancer. This study aimed to determine the incidence and prognostic significance of these lesions. Methods and MaterialsA single institution's colorectal cancer (CRC) database was searched for patients with early-stage rectal cancer, defined as a cT1-2N0 tumor on magnetic resonance imaging (MRI). Abdominal CT scans of these patients were assessed for the presence of liver lesions and categorized according to their morphology. Preoperative MRI scans of the liver and abdominal follow-up imaging were assessed to determine whether the liver lesions found during staging CT appeared to be CRC metastases or not. ResultsIn a consecutive cohort of 1232 patients with CRC who had undergone surgery, 84 patients with early-stage rectal cancer (cT1-2N0 on MRI) were identified. Of those 84 patients, 45 (54%) had 1 or more liver lesions on staging CT; a total of 122 liver lesions were observed, consisting of 95 indeterminate lesions (78%), 25 cysts (20%), and 2 hemangiomas (2%). Preoperative MRI of the liver and regular follow-up imaging revealed no synchronous or metachronous liver metastases in this cohort. ConclusionsIn this study, small, hypoattenuating, indeterminate lesions of the liver were common in patients diagnosed with early rectal cancer and seemed to have no clinical significance. Additional preoperative imaging or follow-up imaging for indeterminate liver lesions in such patients may be unnecessary.

Noninvasive staging of liver fibrosis: review of current quantitative CT and MRI-based techniques.

Liver fibrosis features excessive protein accumulation in the liver interstitial space resulting from repeated tissue injury due to chronic liver disease. Liver fibrosis eventually proceeds to cirrhosis and associated complications. So, early diagnosis and staging of liver fibrosis are of vital importance for clinical treatment. Liver biopsy remains the gold standard for the diagnosing and staging of fibrosis, but it is suboptimal due to various limitations. Recently, efforts have been made to migrate toward noninvasive techniques for assessing liver fibrosis. CT is relatively easy to perform, relatively standardized for different scanners, and does not require additional hardware in liver fibrosis staging. MRI is frequently performed to characterize indeterminate liver lesions. Because it does not use ionizing radiation and features high image contrast, its role has increased in the staging of liver fibrosis. More recently, several studies on liver fibrosis staging using deep learning algorithms in CT or MRI have been proposed and have shown meaningful results. In this review, we summarize the basic concept, diagnostic performance, and advantages and limitations of each technique to noninvasively stage liver fibrosis.

Imaging Characteristics and Management of Infected Hepatic Hemangioma: Case-in Discussion

AbstractHepatic hemangiomas are the most common type of benign liver tumors. We present a case of an infected hepatic hemangioma, which posed a diagnostic challenge. A 43-year-old female presented with right upper quadrant pain after blunt force trauma and intentional weight loss. CT and MRI were done, showing a posterior right lobe liver mass. Imaging characteristics were thought to be suggestive of metastatic disease, with a differential diagnosis of abscess. Drainage and biopsy of the mass revealed Streptococcus sp. infection, and pathology showed a cavernous hemangioma with inflammation. Patients presenting with systemic symptoms and an indeterminate liver mass on imaging should be evaluated for infected hepatic hemangiomas. Biopsy may be needed to rule out cancer. Management may include surgical resection; however, antibiotics and percutaneous drainage can suffice, as in this case.