Bita V. Naini

Total parenteral nutrition therapy and liver injury: a histopathologic study with clinical correlation

Total parenteral nutrition (TPN) therapy is a well-recognized cause of liver injury. The histologic changes attributed to TPN in the literature vary widely. In this study, we describe the histopathologic changes associated with TPN therapy and relate these changes to various clinical parameters. We conducted a retrospective study of 89 patients who underwent biopsy or liver transplantation while on TPN. We report that (1) ductopenia, a previously unreported finding, is seen in a significant number of patients on TPN. It is more frequently seen in patients with low stage of fibrosis and may have an inverse relationship with the length of therapy; (2) Perivenular fibrosis is a feature frequently seen in patients with high-stage portal fibrosis. In fact, we find the combination of portal and perivenular fibrosis to be a characteristic of TPN injury; (3) Infants are more susceptible to TPN-related hepatocellular injury, are more likely to develop fibrosis, and progress to high-stage fibrosis more rapidly than older children and adults; (4) Cholestasis, although more common in infants, is the most common pathologic finding in all age groups; (5) Steatosis is more commonly seen in older children and adults than in infants; (6) Progression to fibrosis in infants may be dependent on the length of therapy and the underlying disease for which TPN is administered; and (7) Clinical markers of liver injury (eg, elevated liver enzymes) do not predict the degree of hepatocellular injury or fibrosis, and therefore, serial biopsies may be indicated for patients on TPN therapy.

Assessment of hepatic steatosis by transplant surgeon and expert pathologist: A prospective, double‐blind evaluation of 201 donor livers

An accurate clinical assessment of hepatic steatosis before transplantation is critical for successful outcomes after liver transplantation, especially if a pathologist is not available at the time of procurement. This prospective study investigated the surgeons accuracy in predicting hepatic steatosis and organ quality in 201 adult donor livers. A steatosis assessment by a blinded expert pathologist served as the reference gold standard. The surgeons steatosis estimate correlated more strongly with large‐droplet macrovesicular steatosis [ld‐MaS; nonparametric Spearman correlation coefficient (rS) = 0.504] versus small‐droplet macrovesicular steatosis (sd‐MaS; rS = 0.398). True microvesicular steatosis was present in only 2 donors (1%). Liver texture criteria (yellowness, absence of scratch marks, and round edges) were mainly associated with ld‐MaS (variance = 0.619) and were less associated with sd‐MaS (variance = 0.264). The prediction of ≥30% ld‐MaS versus <30% ld‐MaS was excellent when liver texture criteria were used (accuracy = 86.2%), but it was less accurate when the surgeons direct estimation of the steatosis percentage was used (accuracy = 75.5%). The surgeons quality grading correlated with the degree of ld‐MaS and the surgeons steatosis estimate as well as the incidence of poor initial function and primary nonfunction. In conclusion, the precise estimation of steatosis remains challenging even in experienced hands. Liver texture characteristics are more helpful in identifying macrosteatotic organs than the surgeons actual perception of steatosis. These findings are especially important when histological assessment is not available at the donors hospital. Liver Transpl 19:437–449, 2013.

TLR4 Signaling via NANOG Cooperates With STAT3 to Activate Twist1 and Promote Formation of Tumor-initiating Stem-like Cells in Livers of Mice.

BACKGROUND & AIMS Obesity and alcohol consumption contribute to steatohepatitis, which increases the risk for hepatitis C virus (HCV)-associated hepatocellular carcinomas (HCCs). Mouse hepatocytes that express HCV-NS5A in liver up-regulate the expression of Toll-like receptor 4 (TLR4), and develop liver tumors containing tumor-initiating stem-like cells (TICs) that express NANOG. We investigated whether the TLR4 signals to NANOG to promote the development of TICs and tumorigenesis in mice placed on a Western diet high in cholesterol and saturated fat (HCFD). METHODS We expressed HCV-NS5A from a transgene (NS5A Tg) in Tlr4-/- (C57Bl6/10ScN), and wild-type control mice. Mice were fed a HCFD for 12 months. TICs were identified and isolated based on being CD133+, CD49f+, and CD45-. We obtained 142 paraffin-embedded sections of different stage HCCs and adjacent nontumor areas from the same patients, and performed gene expression, immunofluorescence, and immunohistochemical analyses. RESULTS A higher proportion of NS5A Tg mice developed liver tumors (39%) than mice that did not express HCV NS5A after the HCFD (6%); only 9% of Tlr4-/- NS5A Tg mice fed HCFD developed liver tumors. Livers from NS5A Tg mice fed the HCFD had increased levels of TLR4, NANOG, phosphorylated signal transducer and activator of transcription (pSTAT3), and TWIST1 proteins, and increases in Tlr4, Nanog, Stat3, and Twist1 messenger RNAs. In TICs from NS5A Tg mice, NANOG and pSTAT3 directly interact to activate expression of Twist1. Levels of TLR4, NANOG, pSTAT3, and TWIST were increased in HCC compared with nontumor tissues from patients. CONCLUSIONS HCFD and HCV-NS5A together stimulated TLR4-NANOG and the leptin receptor (OB-R)-pSTAT3 signaling pathways, resulting in liver tumorigenesis through an exaggerated mesenchymal phenotype with prominent Twist1-expressing TICs.

Diffuse cirrhosis-like hepatocellular carcinoma: a clinically and radiographically undetected variant mimicking cirrhosis.

A rare variant of hepatocellular carcinoma (HCC) is encountered that produces small cirrhosis-like nodules diffusely throughout the liver (CL-HCC), instead of a larger evident mass. This pattern remains undetected as carcinoma clinically and radiographically and is unexpectedly discovered after liver transplantation in the explanted native liver. We studied 10 such cases (9 males and 1 female, age 35 to 80 y) from 4 medical centers. The pretransplant clinical, laboratory, and radiographical studies were reviewed to determine the cause and stage of liver disease, α-fetoprotein (AFP) levels, and detectability of a mass on imaging. All 10 cases had underlying cirrhosis of varying etiology [3 hepatitis C virus (HCV), 3 alcoholic hepatitis, 1 hepatitis B virus, 1 autoimmune, and 2 mixed HCV/alcoholic hepatitis and hemochromatosis/HCV] and underwent orthotopic liver transplantation with no preoperative clinical suspicion of HCC. Ultrasound and/or dynamic imaging showed cirrhosis and no definite HCC. AFP levels were only mildly elevated in only 3 of 10 cases (144, 150, and 252 ng/mL). Grossly, there were innumerable (from about 20 to >1000) small CL-HCC nodules (0.2 to 0.6 cm) scattered among cirrhotic nodules. Histologically, these were well or moderately differentiated HCC, often with pseudoglandular pattern, perinodular sclerotic rims, cholestasis, frequent Mallory bodies, and small vessel invasion. In addition to the usual HCC immunophenotype, CL-HCC showed frequent ubiquitin and cytoplasmic and membranous CD10 positivity, relatively low Ki-67 proliferative index and absence of AFP immunohistochemically. CL-HCC warrants recognition as a unique HCC variant that evades pretransplant detection despite massive tumor burden, mimics cirrhotic nodules, and shows some uncommon pathologic and immunophenotypical characteristics.

A histopathologic scoring system as a tool for standardized reporting of chronic (ileo)colitis and independent risk assessment for inflammatory bowel disease

Pathologists regularly evaluate for the presence of chronic (ileo)colitis in lower gastrointestinal mucosal biopsies, for which a major differential diagnosis is inflammatory bowel disease. Although the histologic features of chronic (ileo)colitis are clearly defined, there is no standard, experimentally derived and validated terminology to document these findings in pathology reports and to convey the likelihood of inflammatory bowel disease in a compact, consistent style. This study had 2 retrospective and 1 prospective phases. In phase 1, we developed a histopathologic scoring system for chronic (ileo)colitis and measured the agreement in scoring between pathologists. In phase 2, we emulated the surgical pathology practice by scoring mucosal biopsies of 164 patients who had undergone lower gastrointestinal endoscopies for clinical suspicion of (ileo)colitis. The cases were matched to 6 different groups based on clinical diagnoses. In phase 3, we prospectively assessed accuracy and ease of application of the scoring system in our practice. The scoring system showed low interobserver variability (correlation coefficient, 0.94-0.96) and distinguished chronic (ileo)colitis from negative cases. In addition, it enabled us to provide probabilistic diagnostic statements based on total scores and their positive predictive values, conveying the likelihood of inflammatory bowel disease as low (<20%), intermediate (∼50%), and high (∼90%). In conclusion, this histopathologic scoring system might be a useful approach to report the findings of lower gastrointestinal mucosal biopsies and to provide measured opinion regarding chronic (ileo)colitis independent of available clinical information. In addition, a defined set of diagnostic statements with regard to likelihood of inflammatory bowel disease would reduce interpretive variability.

Barrett's Esophagus: A Comprehensive and Contemporary Review for Pathologists.

This review provides a summary of our current understanding of, and the controversies surrounding, the diagnosis, pathogenesis, histopathology, and molecular biology of Barrett’s esophagus (BE) and associated neoplasia. BE is defined as columnar metaplasia of the esophagus. There is worldwide controversy regarding the diagnostic criteria of BE, mainly with regard to the requirement to histologically identify goblet cells in biopsies. Patients with BE are at increased risk for adenocarcinoma, which develops in a metaplasia-dysplasia-carcinoma sequence. Surveillance of patients with BE relies heavily on the presence and grade of dysplasia. However, there are significant pathologic limitations and diagnostic variability in evaluating dysplasia, particularly with regard to the more recently recognized unconventional variants. Identification of non–morphology-based biomarkers may help risk stratification of BE patients, and this is a subject of ongoing research. Because of recent achievements in endoscopic therapy, there has been a major shift in the treatment of BE patients with dysplasia or intramucosal cancer away from esophagectomy and toward endoscopic mucosal resection and ablation. The pathologic issues related to treatment and its complications are also discussed in this review article.

A correlation study of diagnostic fine-needle aspiration with histologic diagnosis in cystic neck lesions.

The clinical diagnosis of a mass in the neck region encompasses a wide spectrum of differential diagnosis. Fine‐needle aspiration is a quick and safe technique, which can provide useful information for initial assessment and further therapeutic measures. The aim of this retrospective study was to evaluate the performance characteristics of the fine‐needle aspiration (FNA) in cystic neck lesions. Of 142 patients with FNA for cystic neck masses during 2002–2007, 92 cases were selected with a follow‐up histologic diagnosis, excluding the cystic colloid nodule of the thyroid. The cases were divided into salivary gland cystic neck (37 patients) and non‐salivary cystic neck (55 patients) mass groups. False‐positive and false‐negative diagnoses were applied only to the malignant lesions after confirmation by histopathology. In the first group, nine malignant and 28 benign diagnoses were made by FNA; of which three were false‐negative. In the second group, there were nine malignant and 46 benign diagnoses with three false negatives. The overall performance of the FNA showed 76% sensitivity and 100% specificity. In conclusion, FNA of the cystic neck lesions offers an invaluable and highly specific initial diagnostic approach for the management of the patients. Diagn. Cytopathol. 2009.

Chromophobe hepatocellular carcinoma with abrupt anaplasia: a proposal for a new subtype of hepatocellular carcinoma with unique morphological and molecular features

Hepatocellular carcinomas exhibit heterogeneous morphologies by routine light microscopy. Although some morphologies represent insignificant variations in growth patterns, others may represent unrecognized subtypes of hepatocellular carcinoma. Identification of these subtypes could lead to separation of hepatocellular carcinomas into discrete groups with unique underlying genetic changes, prognosis, or therapeutic responses. In order to identify potential subtypes, two pathologists independently screened a cohort of 219 unselected hepatocellular carcinoma resection specimens and divided cases into potential subtypes. One of these promising candidate subtypes was further evaluated using histological and molecular techniques. This subtype was characterized by a unique and consistent set of histological features: smooth chromophobic cytoplasm, abrupt focal nuclear anaplasia (small clusters of tumor cells with marked nuclear anaplasia in a background of tumor cells with bland nuclear cytology), and scattered microscopic pseudocysts—we designate this variant as ‘chromophobe hepatocellular carcinoma with abrupt anaplasia’. Thirteen cases were identified (6% of all hepatocellular carcinomas), including 6 men and 7 women with an average age of 61 years. Six cases occurred in cirrhotic livers. Serum AFP was elevated in 6 out of 10 cases. There were a variety of underlying liver diseases, but cases were enrichment for chronic hepatitis B, P=0.006. Interestingly, at the molecular level, this variant was strongly associated with the alternative lengthening of telomere (ALT) phenotype by telomere FISH. ALT is a telomerase-independent mechanism of telomere maintenance and is found in approximately 8% of unselected hepatocellular carcinomas. In contrast, 11/12 (92%) of the cases of chromophobe hepatocellular carcinoma with abrupt anaplasia were ALT-positive. In summary, we propose that chromophobe hepatocellular carcinoma with abrupt anaplasia represents a new subtype of hepatocellular carcinoma with unique morphological and molecular features.

Polypectomy is adequate treatment for adenoma-like dysplastic lesions (DALMs) in Crohn's disease.

Background:The purpose of this study was to reevaluate the clinical and pathologic features and outcomes in patients with Crohns disease with an adenoma-like dysplasia-associated lesion or mass (DALMs) to determine if polypectomy is adequate treatment. Methods:The clinical, endoscopic and pathologic features, and outcomes of 50 patients with Crohns disease, each with ≥1 adenoma-like DALM were evaluated. The median length of follow-up was 39 months (range: 0.5–156 months). Results:Of the 50 patients with Crohns disease (male to female ratio, 30:20; median age: 53 years; median duration of disease: 83 months), 11 had ileal disease, 26 had colonic disease, and 13 had both ileal and colonic disease. Approximately 43% of polyps occurred within areas of previous or concurrent colitis, whereas 57% occurred in areas not previously involved by colitis. Most polyps had tubular architecture and contained low-grade dysplasia. Of the patients who had polypectomy followed by surveillance, 45% developed new adenoma-like DALMs, but none developed flat dysplasia and only 1 had adenocarcinoma at the time of resection, which was within 3 months of polypectomy. There were no differences in the clinical or pathologic features or outcomes in patients who had adenoma-like DALMs within versus outside areas of previous or concurrent colitis, except that the former showed a higher risk of developing new polyps within areas of colitis and near the site of the original polyp compared with the latter. Conclusions:Patients with Crohns disease who develop an adenoma-like DALM, regardless of its location in relationship to previous or concurrent colitis, may be treated safely with polypectomy and continued surveillance.

Hepatocellular Neoplasms Arising in Association With Androgen Use.

Correlation between androgen use and hepatocellular neoplasia is well established. However, there are no detailed studies of the histopathology and immunohistochemical/molecular profile of these tumors. We studied 9 patients with androgen-associated hepatocellular neoplasms. In addition to histology, immunostains for liver fatty acid–binding protein, &bgr;-catenin, glutamine synthetase, C-reactive protein, and serum amyloid A were utilized for tumor subtyping. Molecular testing using Solid Tumor Targeted Cancer Panel was performed on 3 cases. The neoplasms were predominantly seen in male individuals (7/9). Two patients (22%) had multifocal lesions. All lesions had architectural and 4/9 had cytologic atypia. Cholestasis was present in 6/9 cases. Reticulin was focally disrupted in 5/9 cases. Given the clinical setting, all lesions were classified as well-differentiated hepatocellular neoplasms of uncertain malignant potential. In cases with follow-up (6/9 cases, 67%), there were no recurrences or metastases. On the basis of the immunoprofile, 7 (78%) cases were &bgr;-catenin activated (including 1 hepatic adenoma with concurrent hepatocyte nuclear factor 1&agr; inactivation) and 2 (22%) had inflammatory phenotype. Somatic mutations in CTNNB1 were detected in all 3 tested cases (all &bgr;-catenin activated by immunostain), all involving exon-3. Our data indicate that androgen-associated hepatocellular neoplasms most often develop in male individuals and always show some degree of atypia and/or focal reticulin disruption. Most are &bgr;-catenin activated, often harboring CTNNB1 exon-3 mutations, and a minority is inflammatory type. Although &bgr;-catenin and inflammatory pathways likely play a role in pathogenesis, the heterogenous molecular profile suggests there are other (yet to be characterized) primary oncogenic mechanisms in this unique tumor type.