Steroid-resistant minimal change nephrotic syndrome associated with thymoma treated effectively with rituximab following thymectomy and cyclosporine: a case report.

BACKGROUND: Minimal change nephrotic syndrome (MCNS) can be complicated by thymoma; however, no standard therapy for thymoma-associated MCNS has yet been established. We herein describe a case of steroid-resistant MCNS associated with thymoma, treated effectively with rituximab. CASE PRESENTATION: A 71-year-old Japanese man was referred to our department with severe proteinuria (20 g/gCr). Renal biopsy showed minimal change disease and computed tomography revealed an anterior mediastinal mass. Based on these findings, he was diagnosed with thymoma-associated MCNS. He was treated with oral prednisolone (50 mg/day) and cyclosporine, and underwent thymectomy and plasma exchange. However, no improvement in proteinuria was observed. He therefore received intravenous rituximab 500 mg, resulting in a marked decrease in proteinuria from 5328 to 336 mg/day after 1 week. CONCLUSIONS: This case suggests that rituximab might be an effective therapy in patients with steroid-resistant MCNS associated with thymoma.

Chronic active Epstein-Bar virus infection complicated by pulmonary artery hypertension.

Chronic active Epstein-Bar virus infection (CAEBV) is known to cause various symptoms. Although pulmonary artery hypertension (PAH) has been reported as a cardiovascular complication of CAEBV, the mechanisms of PAH and the effects of treatment have not been fully elucidated. We experienced 4 adult patients with CAEBV complicated by PAH. All of them received treatment for PAH with a vasodilator followed by chemotherapy with or without allogeneic hematopoietic cell transplantation for CAEBV. In all of these patients, the transtricuspid pressure gradient improved under treatment with vasodilator, and further improvement was observed under treatment for CAEBV in 3 patients. Autopsy was performed in 2 patients, which revealed EBER-positive cells and a change in the pulmonary artery at each stage in the pathology. In conclusion, EBV-infected cells can cause vasculitis and finally PAH. However, PAH complicated with CAEBV can be improved by PAH medication and treatment of CAEBV.

Multiparametric US for Identifying Patients with High-Risk NASH: A Derivation and Validation Study.

Background Nonalcoholic fatty liver disease (NAFLD) is common in the general population but identifying patients with high-risk nonalcoholic steatohepatitis (NASH) who are candidates for pharmacologic therapy remains a challenge. Purpose To develop a score to identify patients with high-risk NASH, defined as NASH with an NAFLD activity score (NAS) of 4 or greater and clinically significant fibrosis (stage 2 [F2] or higher). Materials and Methods This was a cross-sectional secondary analysis of data prospectively collected between April 2017 and March 2019 for a group of patients with NAFLD in Japan (Japan NAFLD, the derivation data set) with contemporaneous two-dimensional shear-wave elastography and biopsy-proven NAFLD (age range, 20-89 years). Three US markers (liver stiffness [LS, measured in kilopascals], attenuation coefficient [AC, measured in decibels per centimeter per megahertz], and dispersion slope [DS, measured in meters per second per kilohertz]) were determined, together with aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels and the AST-to-ALT ratio. The best-fit multivariate logistic regression model for identifying patients with high-risk NASH was determined. Diagnostic performance was assessed by using the area under the receiver operating characteristic curve (AUC). The findings were validated in an independent data set (Korea NAFLD; age range, 20-78 years). Results The Japan NAFLD data set included 111 patients (mean age, 53 years ± 18 [standard deviation]; 57 men), 84 (76%) with NASH. The Korea NAFLD data set included 102 patients (mean age, 48 years ± 18; 43 men), 55 (36%) with NASH. The most predictive model (LAD NASH score) combined LS, AC, and DS. Performance was satisfactory in both the derivation sample (AUC, 0.86; 95% CI: 0.79, 0.93) and the validation sample (AUC, 0.88; 95% CI: 0.80, 0.95). The LAD NASH score showed a positive predictive value of 86.5% and a negative predictive value of 87.5% for high-risk NASH in the derivation sample. Conclusion A score combining three US markers may be useful for noninvasive identification of patients with high-risk nonalcoholic steatohepatitis for inclusion in clinical trials and pharmacologic therapy. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Lockhart in this issue.

A method to obtain reproducible Ki-67 indices in lung adenocarcinoma.

AIMS: Proliferative activity, evaluated from the Ki-67 index, is a strong prognostic factor in lung adenocarcinoma (LADC). Here, we optimised a procedure to measure the Ki-67 index and establish the best cut-off value. METHODS AND RESULTS: We examined 342 stage I LADCs for the immunohistochemical expression of Ki-67 using different antibodies, MIB1 and SP6. The results revealed the superior specificity of SP6; therefore, SP6 was used in subsequent analyses. Slides were scanned with a virtual slide system. Using software, tumour cells were counted in a whole tumour. Thereafter, the tumour was evenly subdivided into 0.25-mm2 tiles. The frequency of positive cells was counted in each tile of an invasive area or the whole tumour. We calculated the number of tumour cells required to produce a 95% confidence interval (CI) <0.05. Additionally, we calculated coverage probabilities (CP) using two different methods, counting any number or 200 cells per tile. The results showed that we could meet our goal by counting 2000 cells from 10 random tiles (200 cells each) in invasive areas. CONCLUSIONS: We successfully developed an optimal procedure for determination of the Ki-67 labelling index using an SP6 antibody, which provided CP > 70% and CI of <0.05 in more than 90% of cases. Furthermore, we identified an optimal cut-off value of 0.12 with an alternative of 0.15, based on disease recurrence. This procedure and the cut-off values may be used in the routine pathological diagnosis of LADC.

The Role of Multiparametric US of the Liver for the Evaluation of Nonalcoholic Steatohepatitis.

Background Nonalcoholic steatohepatitis (NASH) is diagnosed with histopathologic testing, but noninvasive surrogate markers are desirable for screening patients who are at high risk of NASH. Purpose To investigate the diagnostic performance of dispersion slope, attenuation coefficient, and shear-wave speed measurements obtained using two-dimensional (2D) shear-wave elastography (SWE) in assessing inflammation, steatosis, and fibrosis and in the noninvasive diagnosis of NASH in patients suspected of having nonalcoholic fatty liver disease (NAFLD). Materials and Methods This prospective study collected data from 120 consecutive adults who underwent liver biopsy for suspected NAFLD and were enrolled between April 2017 and March 2019. Three US parameters (dispersion slope [(m/sec)/kHz], attenuation coefficient [dB/cm/MHz], and shear-wave speed [in meters per second]) were measured using a 2D SWE system immediately before biopsy. The biopsy specimens were scored by one expert pathologist according to the Nonalcoholic Steatohepatitis Clinical Research Network criteria (119 participants underwent a histologic examination). Diagnostic performance was assessed using the area under the receiver operating characteristic curve (AUC) for the categories of inflammation, steatosis, and fibrosis. Results One hundred eleven adults (mean age, 53 years ± 18 [standard deviation]; 57 men) underwent a US examination. Dispersion slope enabled the identification of lobular inflammation, with an AUC of 0.95 (95% confidence interval [CI]: 0.91, 0.10) for an inflammation grade greater than or equal to A1 (mild), 0.81 (95% CI: 0.72, 0.89) for an inflammation grade greater than or equal to A2 (moderate), and 0.85 (95% CI: 0.74, 0.97) for an inflammation grade equal to A3 (marked). Attenuation coefficient enabled the identification of steatosis, with an AUC of 0.88 (95% CI: 0.80, 0.97) for steatosis grade greater than or equal to S1 (mild), 0.86 (95% CI: 0.79, 0.93) for steatosis grade greater than or equal to S2 (moderate), and 0.79 (95% CI: 0.68, 0.89) for steatosis grade equal to S3 (severe). Shear-wave speed enabled the identification of fibrosis, with an AUC of 0.79 (95% CI: 0.69, 0.88) for fibrosis stage greater than or equal to F1 (portal fibrosis), 0.88 (95% CI: 0.82, 0.94) for fibrosis stage greater than or equal to F2 (periportal fibrosis), 0.90 (95% CI: 0.84, 0.96) for fibrosis stage greater than or equal to F3 (septal fibrosis), and 0.95 (95% CI: 0.91, 0.99) for fibrosis stage equal to F4 (cirrhosis). The combination of dispersion slope, attenuation coefficient, and shear-wave speed showed an AUC of 0.81 (95% CI: 0.71, 0.91) for the diagnosis of NASH. Conclusion Dispersion slope, attenuation coefficient, and shear-wave speed were found to be useful for assessing lobular inflammation, steatosis, and fibrosis, respectively, in participants with biopsy-proven nonalcoholic fatty liver disease. © RSNA, 2020 Online supplemental material is available for this article.

Pancreaticoduodenectomy for a primary duodenal capicua transcriptional repressor (CIC) -rearranged sarcoma with severe bleeding: a case report.

BACKGROUND: Capicua transcriptional repressor (CIC) -rearranged sarcoma is characterized by small round cells, histologically similar to Ewing sarcoma. However, CIC-rearranged sarcoma has different clinical, histological, and immunohistochemical features from Ewing sarcoma. It is important to differentiate between these tumors. CASE PRESENTATION: The patient is a 44-year-old man with a duodenal tumor diagnosed in another hospital who presented with a history of melena. Laboratory studies showed anemia with a serum hemoglobin of 6.0 g/dL. He was hospitalized and gastrointestinal bleeding was controlled successfully with endoscopy. However, he suffered from appetite loss and vomiting and progression of anemia a few weeks after presentation. Upper gastrointestinal endoscopy showed a circumferential soft tumor in the second portion of the duodenum and the endoscope could not pass distally. Computed tomography scan showed a greater than 10 cm tumor in the duodenum, with compression of the inferior vena cava and infiltrating the ascending colon. A definitive pathologic diagnosis could not be established despite four biopsies from the tumor edge. Due to gastrointestinal obstruction and progression of anemia, a pylorus-preserving pancreaticoduodenectomy with partial resection of the inferior vena cava and right hemicolectomy was performed as a complete tumor resection. The tumor was diagnosed as a CIC-rearranged sarcoma, but 2 months postoperatively local recurrence and distant metastases to the liver and lung were found. The patient died 3 months after surgery. CONCLUSIONS: Although the only definitive treatment for CIC-rearranged sarcoma is surgical resection, the CIC-rearranged sarcoma is highly malignant with a poor prognosis even after radical resection. More research is needed to establish optimal treatment strategies.

TAFRO Syndrome with an Anterior Mediastinal Mass and Lethal Autoantibody-Mediated Thrombocytopenia: An Autopsy Case Report.

TAFRO syndrome, a rare systemic inflammatory disease, can lead to multiorgan failure without appropriate treatment. Although thrombocytopenia is frequently seen in patients with TAFRO syndrome, little is known about its pathogenesis. Moreover, while recent studies have reported the presence of an anterior mediastinal mass in some patients, the pathological status of this remains unclear. Here, we report a case of fatal bleeding in a patient with TAFRO syndrome accompanied by an anterior mediastinal mass. A 55-year-old female was transferred to our hospital with a 2-week history of fever, epistaxis, and dyspnea. Laboratory tests revealed severe thrombocytopenia, computed tomography (CT) showed pleural effusions, and bone marrow biopsy revealed reticulin myelofibrosis. We suspected TAFRO syndrome, but the CT scan showed an anterior mediastinal mass that required a biopsy to exclude malignancy. She soon developed severe hemorrhagic diathesis and died of intracranial hemorrhage despite intensive treatment. She had multiple autoantibodies against platelets, which caused platelet destruction. An autopsy of the mediastinal mass revealed fibrous thymus tissues with infiltration by plasma cells. Our case suggests that thrombocytopenia could be attributed to antibody-mediated destruction and could be lethal. Hence, immediate treatment is imperative in cases of severe thrombocytopenia, even when accompanied by an anterior mediastinal mass.

Overexpression of matriptase in tumor stroma is a poor prognostic indicator of extrahepatic bile duct cancer.

Bile duct cancer is known to contain numerous fibroblasts, and reported to recruit cancer- associated fibroblasts by secreting platelet-derived growth factor-D (PDGF-D) which needs serine proteases, such as matriptase, to behave as a ligand. However, their expression pattern, and prognostic value have not been clarified. In this study, we investigated the clinicopathological significance of PDGF-D and matriptase expression in patients with extrahepatic bile duct cancer. The samples were obtained from 256 patients who underwent the surgical resection between 1991 and 2015, and the expression levels of PDGF-D and matriptase were evaluated immunohistochemically. Staining intensities and distribution were scored, and finally classified into low and high expression groups in cancer cells and stroma respectively. High expression of matriptase in the cancer stroma was detected in 91 tumors (40%). The high stromal matriptase expression was significantly associated with shorter recurrence-free survival (RFS) and overall survival (OS) (P = 0.0027 and 0.0023, respectively). Multivariate analyses also demonstrated that the stromal matriptase expression level was an independent influential factor in RFS (P = 0.0050) and OS (P = 0.0093). Our findings suggest that the high stromal matriptase expression was strongly associated with tumor progression, recurrence and poor outcomes in patients with extrahepatic bile duct cancer.

A case of primary aldosteronism caused by unilateral multiple adrenocortical micronodules presenting as muscle cramps at rest: The importance of functional histopathology for identifying a culprit lesion.

Unilateral multiple adrenocortical micronodules (UMNs) constitute a rare subset of primary aldosteronism (PA) characterized by the hypersecretion of aldosterone derived from multiple small nodules in the zona glomerulosa of the unilateral adrenal grand. This case study describes a 49-year-old man with PA and UMNs who presented with muscle cramps at rest due to hypokalemia. The patient had a 6-year history of hypertension treated with antihypertensive drugs. Imaging studies revealed bilateral adrenal nodules as large as 5 mm. Adrenal venous sampling confirmed unilateral PA; therefore, the patient underwent the removal of the affected adrenal gland. Macroscopically, the removed adrenal gland exhibited irregular adrenocortical thickening accompanied by ill-defined, adrenocortical macronodules as large as 6 mm. The zona glomerulosa was histologically hyperplastic. However, an immunohistochemistry test of the steroidogenic enzymes revealed that these macronodules and the hyperplastic glomerular layer tested negative for CYB11B2. Moreover, we observed adrenocortical micronodules as large as 0.5 mm that tested immunohistochemically positive for CYP11B2 and HSD3B2 but negative for CYP17A1 and CYP11B1. Thus, UMNs were diagnosed. This case instructively indicates that a grossly or histologically detectable nodular lesion is not necessarily a culprit lesion for PA. Therefore, functional histopathology is indispensable for the correct subclassification of PA.

Randomized trial comparing a side-port needle and standard needle for EUS-guided histology of pancreatic lesions.

BACKGROUND AND AIMS: A side-port needle has been developed to improve diagnostic accuracy by obtaining more cellular material during EUS-guided FNA (EUS-FNA). We compared the accuracy rate of histology and the quality of histologic specimens from 22-gauge (G) side-port and standard needles for EUS-FNA of a solid pancreatic mass in a multicenter, prospective, randomized control trial. METHODS: Between January 2013 and September 2013, 160 consecutive patients with a suspected solid pancreatic mass at 5 tertiary referral centers were enrolled. Patients were randomized to the 22G side-port needle or 22G standard needle group. The primary endpoint was the diagnostic accuracy of histology. Secondary endpoints were the quality of the histologic specimen (quantity of tissue, degree of GI contamination, and amount of blood). RESULTS: An analysis of 154 patients (side-port, 76, vs standard, 78) was performed. Six patients were excluded because of no pancreatic mass on EUS. There was no significant difference in the rate of diagnostic accuracy of histology (side-port, 87% [66/76], vs standard, 82% [64/78]; P = .51). Samples that enabled histologic interpretation were obtained in 64% (47/73) and 43% (33/77) of patients from the side-port and standard groups, respectively (P = .009). No significant difference was seen in the degree of GI contamination and amount of blood between groups. CONCLUSIONS: There was no significant difference in the accuracy rate of histology between needle types. The side-port needle was superior to the standard needle in terms of obtaining samples that enabled histologic interpretation.

Assessment of various types of US findings after irreversible electroporation in porcine liver: comparison with radiofrequency ablation.

PURPOSE: To assess various ultrasound (US) findings, including B-mode, shear-wave elastography (SWE), and contrast-enhanced US, in accurately assessing ablation margins after irreversible electroporation (IRE) based on radiologic-pathologic correlation, and to compare these findings between IRE and radiofrequency (RF) ablation. MATERIALS AND METHODS: IRE (n = 9) and RF ablation (n = 3) were performed in vivo in three pig livers. Each ablation zone was imaged by each method immediately after the procedure and 90 minutes later. Ablation zones were evaluated based on gross pathologic and histopathologic findings in samples from animals euthanized 2 hours after the last ablation. The characteristics and dimensions of the histologic ablation zones were qualitatively and quantitatively compared against each US finding. RESULTS: In B-mode US at 90 minutes after IRE, the ablation zones appeared as hyperechoic areas with a peripheral hyperechoic rim, showing excellent correlation (r(2) = 0.905, P < .0001) with gross pathologic findings. SWE showed that tissue stiffness in the IRE ablation zones increased over time. Contrast-enhanced US depicted the IRE ablation zones as hypovascular areas in the portal phase, and showed the highest correlation (r(2) = 0.923, P < .0001) with gross pathologic findings. The RF ablation zones were clearly visualized by B-mode US. SWE showed that tissue stiffness after RF ablation was higher than after IRE. Contrast-enhanced US depicted the RF ablation zones as avascular areas. CONCLUSIONS: IRE and RF ablation zones can be most accurately predicted by portal-phase contrast-enhanced US measurements obtained immediately after ablation.

Establishment of successively transplantable rabbit VX2 cancer cells that express enhanced green fluorescent protein.

Morphological detection of cancer cells in the rabbit VX2 allograft transplantation model is often difficult in a certain region such as serosal cavity where reactive mesothelial cells mimic cancer cells and both cells share common markers such as cytokeratins. Therefore, tagging VX2 cells with a specific and sensitive marker that easily distinguishes them from other cells would be advantageous. Thus, we tried to establish a successively transplantable, enhanced green fluorescent protein (EGFP)-expressing VX2 model. Cancer cells obtained from a conventional VX2-bearing rabbit were cultured in vitro and transfected with an EGFP-encoding vector, and then successively transplanted in Healthy Japanese White rabbits (HJWRs) (n = 8). Besides, conventional VX2 cells were transplanted in other HJWRs (n = 8). Clinicopathological comparison analyses were performed between the two groups. The success rate of transplantation was 100% for both groups. The sensitivity and specificity of EGFP for immunohistochemical detection of VX2 cells were 84.3 and 100%, respectively. No significant differences in cancer cell morphology, tumor size (P = 0.742), Ki-67 labeling index (P = 0.878), or survival rate (P = 0.592) were observed between the two. VX2 cells can be genetically altered, visualized by EGFP, and successively transplanted without significant alteration of morphological and biological properties compared to those of the conventional model.

Focal nodular hyperplasia-like lesion of the liver with focal adenoma features associated with idiopathic portal hypertension.

Great progress has been made in the diagnosis of focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA) in the last few years due to the use of molecular criteria. This has allowed us to identify a new type of hepatic nodule. In this case report, we present a male patient with a hepatic nodule associated with idiopathic portal hypertension (IPH) pathologically exhibiting not only the morphological features of FNH, such as ductular reactions, dilated sinusoids, major vascular abnormalities and an immunohistochemical "map-like" pattern of glutamine synthetase (GS), but also the immunohistological features of focal HCA, such as strong expression of serum amyloid A and C-reactive protein and weak expression of GS. As the final diagnosis, the nodule was identified as an FNH-like lesion with focal inflammatory hepatocellular adenoma.

Relationship between the liver tissue shear modulus and histopathologic findings analyzed by intraoperative shear wave elastography and digital microscopically assisted morphometry in patients with hepatocellular carcinoma.

OBJECTIVES: Shear wave elastography is a novel noninvasive method for assessing liver fibrosis by measuring liver stiffness. This study was conducted to evaluate how pathologic changes could have an impact on measured elasticity values in both resected hepatocellular carcinomas and adjacent liver tissue. METHODS: Intraoperative shear wave elastography was performed in 7 patients who underwent liver resection at our institution; 7 hepatocellular carcinomas and adjacent liver tissue were subjected to elastographic measurements. A total of 48 circular regions of interest (ROIs; 3-8 mm in diameter) were located in the hepatocellular carcinomas (n = 37) and adjacent liver tissue (n = 11), and mean stiffness values were obtained from each ROI. All of the histologic images corresponding to the 48 ROIs after surgery were transformed into digital microscopic images by a scanning system, and histologic parameters, such as the proportions of nuclear areas, fatty areas, fibrous areas, and vessel areas, were quantitatively assessed. Relationships between the mean stiffness and the histologic parameters were investigated by the mixed effects model. RESULTS: By univariate analysis, the proportions of collagen fiber areas (P = .039), fibrous areas (P = .045), hepatocellular nuclear areas (P = .045), and nuclear areas other than hepatocellular and lymphoplasmacytic areas (P = .039) showed statistically positive associations with mean stiffness values. Multivariate analysis indicated that the proportion of collagen fiber areas was the strongest pathologic determinant of mean stiffness (P = .008), with hepatocellular nuclear areas also having a significant effect (P = .010). CONCLUSIONS: Fibrosis predictably affects elastographic estimation, but hepatocellular density (ie, hepatocellular nuclear areas) also alters elastographic assessment.

Reappraisal of mechanical exfoliating cytology for the detection of peritoneal dissemination during the surgical staging of epithelial ovarian carcinomas and borderline tumours.

OBJECTIVE: This study aimed to evaluate the usability of peritoneal swabbing cytology (PSC) with cotton swabs as an effective method for the detection of peritoneal metastasis during the staging laparotomy of epithelial ovarian carcinomas and borderline tumours (EOC/BT). STUDY DESIGN: One hundred and ninety-two patients with EOC/BT who underwent laparotomy at the Yokohama City University Hospital from 2004 to 2010 were analysed retrospectively. The positive rates of the PSC and ascites/peritoneal-wash cytology (A/PWC) were compared. RESULTS AND CONCLUSION: Both A/PWC and PSC were performed during laparotomy (n = 140). The rate of metastasis detection with A/PWC was significantly higher than with PSC (50.0 vs. 20.7%, p < 0.001 by χ(2) test). The superior detection ability of A/PWC was observed regardless of the presence of macroscopic peritoneal metastasis in 56 cases with macroscopic peritoneal metastasis, with A/PWC detecting 80.3% of cases versus PSC detecting 37.5% (p = 0.013). In 84 cases without macroscopic peritoneal metastasis, A/PWC detected 29.8% of cases versus 9.5% with PSC (p = 0.003). Our results suggest that PSC is insufficient to evaluate the peritoneal metastasis for the surgical staging of EOC/BT. Other procedures such as subdiaphragmatic A/PWC should be included when possible to maximize the accuracy of diagnosis.

Metastatic Pleomorphic Carcinoma of the Lung with Extensive Chromosomal Rearrangements: An Autopsy Case with a Literature Review.

We herein report a 47-year-old man who presented with progressive paraparesis. Imaging revealed a right upper pulmonary nodule, massive bilateral adrenal metastases, thoracolumbar vertebral osteolysis, and subcutaneous nodules. A biopsy of the right buttock nodule revealed a poorly differentiated metastatic carcinoma with high programmed cell death-ligand 1 expression and extensive chromosomal rearrangements. The patient died 10 days after the initiation of pembrolizumab treatment. Autopsy findings confirmed pulmonary pleomorphic carcinoma with extensive metastases. Quantification of chromosomal rearrangements revealed a jump-up mutation from the normal karyotype, followed by a further incremental increase in the degree of deviation.

Primary Bile Duct Diffuse Large B-cell Lymphoma Diagnosed by Repeated Endoscopic Ultrasound-guided Fine-needle Aspiration and Endoscopic Retrograde Cholangiopancreatography.

A 54-year-old man was admitted with obstructive jaundice. Computed tomography showed common bile duct stricture and a tumor around the celiac artery. Repeated endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) and endoscopic retrograde cholangiopancreatography (ERCP) as well as a laparotomic biopsy around the celiac artery were diagnostically unsuccessful. Since the bile duct stricture progressed, EUS-FNA and ERCP were performed a third time, finally leading to the diagnosis of diffuse large B-cell lymphoma. The treatment plan and prognosis of obstructive jaundice differ greatly depending on the disease. It is important to conduct careful follow-up and repeated histological examinations with appropriate modifications until a diagnosis is made.

Comparison of Kupffer-phase Sonazoid-enhanced sonography and hepatobiliary-phase gadoxetic acid-enhanced magnetic resonance imaging of hepatocellular carcinoma and correlation with histologic grading.

OBJECTIVES: To determine the relative wash-out of hepatocellular carcinomas and dysplastic nodules using Kupffer-phase sonography with Sonazoid (Daiichi-Sankyo, Tokyo, Japan) enhancement and hepatobiliary-phase gadoxetic acid-enhanced magnetic resonance imaging (MRI) in the evaluation of the histopathologic grades of individual nodules. METHODS: This retrospective study included 66 consecutive patients with 78 histologically confirmed hepatocellular carcinomas and dysplastic nodules. In patients with carcinomas, 33 were well differentiated; 29 were moderately differentiated; and 11 were poorly differentiated; and there were 5 dysplastic nodules. All patients underwent both gadoxetic acid-enhanced MRI and Sonazoid-enhanced sonography. The interval between the two imaging examinations was less than 30 days. Six radiologists independently reviewed both images and rated the degree of relative wash-out between the tumorous and nontumorous areas on Kupffer- and hepatobiliary-phase images using a continuous rating scale. We compared these results with the histopathologic grade of each nodule, and the results were then analyzed with multireader multicase receiver operating characteristic analysis. RESULTS: The average Kupffer-phase (P < .001) and hepatobiliary-phase (P = .004) rating scores increased as the carcinomas became less differentiated (Kruskal-Wallis test). The diagnostic accuracies of the average area under the receiver operating characteristic curve, which were estimated using the confidence levels of the relative wash-out of the Kupffer- and hepatobiliary-phase images, were 0.705 and 0.785 for dysplastic nodules versus well-, moderately, and poorly differentiated carcinomas (P = .517), 0.791 and 0.687 for dysplastic nodules and well-differentiated carcinomas versus moderately and poorly differentiated carcinomas (P = .093), and 0.871 and 0.716 for dysplastic nodules and well-and moderately differentiated carcinomas versus poorly differentiated carcinomas (P = .005), respectively. CONCLUSIONS: Kupffer-phase Sonazoid-enhanced sonography and hepatobiliary-phase gadoxetic acid-enhanced MRI may be useful in estimating the histologic grade, although Kupffer-phase Sonazoid-enhanced sonography may be more accurate in distinguishing hepatocellular carcinomas, especially moderately and poorly differentiated types.