Markedly increased duodenal villous surface apoptosis in patients taking pre-exposure prophylaxis (PrEP) against human immunodeficiency virus

AIMS

Pre-exposure prophylaxis (PrEP) consists of combination antiretroviral therapy and is increasingly utilized to prevent human immunodeficiency virus (HIV) in high-risk populations. Two index cases noted during routine care showed markedly increased duodenal villous surface apoptosis in patients on PrEP. We sought to examine the prevalence of this finding and identify any clinicopathologic correlations.

METHODS

Gastrointestinal biopsy specimens from 23 male patients aged 18-40 years taking PrEP and 23 control patients were reviewed. Patients with HIV, inflammatory gastrointestinal diseases, and celiac disease were excluded. Apoptoses were counted on surface epithelium and deep crypts. The highest apoptotic body count per tissue fragment was recorded. Clusters were defined as groups of ≥5 apoptoses. Apoptotic counts between patients taking PrEP and controls were compared using t-tests.

RESULTS

In PrEP patients, the median age was 35 years (range 25-40) and 83% (19/23) were white. The control patients were demographically similar (median age: 32 years [range 23-40]; 70% [16/23] white). Duodenal apoptosis in villous surface epithelium was increased in PrEP patients, with 14/23 (60.9%) patients having ≥10 surface apoptoses compared to 2/23 (8.7%) controls (P = 2.1 × 10-3 ) and 14/23 (61%) having clusters compared to 3/23 (13%) controls (P = 2.0 × 10-3 ). There was no significant association between increased surface apoptosis or clusters and clinical symptoms or duration of PrEP use.

CONCLUSION

Markedly increased villous surface apoptosis, particularly in clusters, is often seen in the duodenum of patients taking PrEP. Although the mechanism and significance are unknown, knowledge of this peculiar finding may prevent unnecessary additional testing.

Arginase-1 is More Specific Than Hepatocyte Paraffin 1 for Differentiating Hepatocellular Carcinomas With Cytoplasmic Clearing from Nonhepatocellular Clear Cell Tumors in Liver Biopsies

Arginase-1 (Arg1) and hepatocyte paraffin antigen 1 (HepPar1) are specific and sensitive markers of hepatocellular differentiation. HepPar1 is a granular cytoplasmic immunostain that may be negative in hepatocellular carcinoma (HCC) with cytoplasmic clearing. Arg1 shows uniform cytoplasmic positivity and frequent nuclear positivity. This study was undertaken to determine the staining pattern of Arg1 in HCC with cytoplasmic clearing and compare its use to HepPar1. Fifteen resected HCCs with cytoplasmic clearing and 31 biopsies of clear cell liver tumors (14 HCCs and 17 nonhepatocellular tumors) were identified. Resections were stained with Arg1 to characterize the pattern, intensity, and extent of Arg1 positivity. Biopsies were stained with Arg1 (n=31) and HepPar1 (n=28). In all, 13/15 resected and 11/14 biopsied HCCs with cytoplasmic clearing showed nuclear positivity for Arg1. Both Arg1 and HepPar1 stained significantly more HCCs than nonhepatocellular tumors (13/14 and 11/12, respectively, with P <0.0001 and P =0.0018, respectively). However, HepPar1 stained significantly more nonhepatocellular tumors (5/12) than Arg1 (0/17, P =0.0445). Arg1 frequently displayed nuclear positivity, and interobserver agreement was better for Arg1 ( K =0.93 vs. 0.79). Overall, Arg1 is more specific than HepPar1 for differentiating HCC with cytoplasmic clearing from nonhepatocellular clear cell tumors in the liver. Its staining characteristics, including nuclear positivity, make it easier to interpret in combination with morphology, improving interobserver variability, and it stains significantly fewer mimics than HepPar1.

Traditional Chinese Medicine, Cordyceps, Related to Hepatoportal Sclerosis

We describe a case of hepatoportal sclerosis (HPS) identified in an 81-year-old woman taking a traditional Chinese herbal supplementation, Cordyceps. The patient presented with splenomegaly and weight loss. After an extensive evaluation, liver biopsy confirmed loss of the small portal veins with characteristics of obstruction at the level of the small and large portal veins, suggestive of HPS. After a comprehensive history and exclusion of other etiological factors, patient's HPS was attributed to Cordyceps use. Ultimately, the patient's features of HPS improved with the cessation of Cordyceps.

Liver fibrosis: the good, the bad, and the patchy-an update

The purpose of this article is to review fibrosis staging systems, reversibility of fibrosis, histologic pattern of fibrosis regression, and recently proposed fibrosis staging systems that address the more nuanced fibrosis information needed clinically for management purposes. In most chronic liver diseases, the extent of liver fibrosis often drives patient outcomes. The evolving knowledge of the reversibility of fibrosis and the observed patterns of fibrosis seen in the setting of remodeling/regression can create staging difficulties, and problems in applying the existing "conventional" staging systems. The heterogeneity of liver fibrosis in congestive liver disease is an emerging problem in biopsies from patients with congestive heart failure. The fibrosis staging in these biopsies is of significant import as it is used to determine suitability of some congestive heart disease patients for heart transplantation alone, dual heart and liver transplantation, or be denied transplantation. Pathologist should be aware of these newly recognized concepts, the recently proposed staging systems that attempt to incorporate these new fibrosis patterns and be able to apply the knowledge in daily practice.

Capecitabine-induced Gastrointestinal Injury Shows a Graft-Versus-Host Disease (GVHD)-like Pattern

Capecitabine is a commonly used oral chemotherapeutic agent. Gastrointestinal (GI) side effects are clinically well-known, however, the histopathologic changes have not been comprehensively studied. This study describes the largest case series (8 patients) characterizing the histopathology of capecitabine-induced GI injury. All patients were adults (median age: 64.5 y, range: 61 to 76 y) and there was gender parity. Patients were receiving treatment for malignancies of the colorectum (n=5), breast (n=1), pancreas (n=1), and appendix (n=1). All had GI symptoms, including 7 with diarrhea and abdominal pain and 1 with melena. Five of 8 (63%) showed graft-versus-host disease (GVHD)-like histologic changes in small intestinal and/or colonic biopsies characterized by crypt disarray and dropout, crypt atrophy, dilated crypts lined by attenuated epithelium, and increased crypt apoptosis. Neuroendocrine cell aggregates were present in 4 of 5 cases. Four of 5 showed patchy prominence in lamina propria eosinophils. One patient receiving concomitant radiation therapy had a small intestinal biopsy showing regenerative changes. Two patients had histologically unremarkable biopsies. On follow-up, capecitabine was discontinued or dose-reduced in all patients. Three of 5 patients with a GVHD-like pattern had clinical improvement, whereas 2 died shortly after biopsy. One with regenerative changes also had radiation dose reduction and improved clinically. Two with unremarkable biopsies improved symptomatically. In summary, capecitabine-related GI injury shows a GVHD-like pattern. Knowledge of this is important to confirm the diagnosis as patients typically improve with dose reduction or discontinuation of the drug.

Glycogenic hepatopathy is associated with type 1 diabetes mellitus in only a minority of cases in a contemporary adult population

OBJECTIVES

This study examines the clinical-pathological profiles of patients with glycogenic hepatopathy in a contemporary cohort of patients at an adult acute care hospital.

METHODS

Liver biopsies with glycogenic hepatopathy were retrieved from the departmental surgical pathology database, the histological findings were studied, and the clinical findings were reviewed.

RESULTS

Five cases of glycogenic hepatopathy were found, including cases associated with type 1 diabetes mellitus (n = 1), type 2 diabetes mellitus (n = 1), corticosteroids (n = 2), and anorexia (n = 2, including the patient with type 1 diabetes). AST and ALT were normal to mildly elevated (13-115 U/L and 7-126 U/L, respectively). Trace ascites was present in two patients. Hepatomegaly was only present in the patient with type 1 diabetes at the time of diagnosis.

CONCLUSIONS

Four of five cases were associated with etiologies other than type 1 diabetes, which is widely reported as the most common etiology of glycogenic hepatopathy. This study suggests that etiologies currently only rarely recognized may actually be more common causes of glycogenic hepatopathy than type 1 diabetes in a contemporary adult population. It is important not only to recognize that these rarely reported causes of glycogenic hepatopathy may be underrecognized, but that the clinical presentation may also be mild.

Machine learning models are superior to noninvasive tests in identifying clinically significant stages of NAFLD and NAFLD-related cirrhosis

BACKGROUND AND AIMS

We assessed the performance of machine learning (ML) models in identifying clinically significant NAFLD-associated liver fibrosis and cirrhosis.

APPROACH AND RESULTS

We implemented ML models including logistic regression (LR), random forest (RF), and artificial neural network to predict histological stages of fibrosis using 17 demographic/clinical features in 1370 patients with NAFLD who underwent liver biopsy, FibroScan, and labs within a 6-month period at multiple U.S. centers. Histological stages of fibrosis (≥F2, ≥F3, and F4) were predicted using ML, FibroScan liver stiffness measurements, and Fibrosis-4 index (FIB-4). NASH with significant fibrosis (NAS ≥ 4 + ≥F2) was assessed using ML, FibroScan-AST (FAST) score, FIB-4, and NAFLD fibrosis score (NFS). We used 80% of the cohort to train and 20% to test the ML models. For ≥F2, ≥F3, F4, and NASH + NAS ≥ 4 + ≥F2, all ML models, especially RF, had primarily higher accuracy and AUC compared with FibroScan, FIB-4, FAST, and NFS. AUC for RF versus FibroScan and FIB-4 for ≥F2, ≥F3, and F4 were (0.86 vs. 0.81, 0.78), (0.89 vs. 0.83, 0.82), and (0.89 vs. 0.86, 0.85), respectively. AUC for RF versus FAST, FIB-4, and NFS for NASH + NAS ≥ 4 + ≥F2 were (0.80 vs. 0.77, 0.66, 0.63). For NASH + NAS ≥ 4 + ≥F2, all ML models had lower/similar percentages within the indeterminate zone compared with FIB-4 and NFS. Overall, ML models performed better in sensitivity, specificity, positive predictive value, and negative predictive value compared with traditional noninvasive tests.

CONCLUSIONS

ML models performed better overall than FibroScan, FIB-4, FAST, and NFS. ML could be an effective tool for identifying clinically significant liver fibrosis and cirrhosis in patients with NAFLD.

Large Cancer Pedigree Involving Multiple Cancer Genes including Likely Digenic MSH2 and MSH6 Lynch Syndrome (LS) and an Instance of Recombinational Rescue from LS

Lynch syndrome (LS), caused by heterozygous pathogenic variants affecting one of the mismatch repair (MMR) genes (MSH2, MLH1, MSH6, PMS2), confers moderate to high risks for colorectal, endometrial, and other cancers. We describe a four-generation, 13-branched pedigree in which multiple LS branches carry the MSH2 pathogenic variant c.2006G>T (p.Gly669Val), one branch has this and an additional novel MSH6 variant c.3936_4001+8dup (intronic), and other non-LS branches carry variants within other cancer-relevant genes (NBN, MC1R, PTPRJ). Both MSH2 c.2006G>T and MSH6 c.3936_4001+8dup caused aberrant RNA splicing in carriers, including out-of-frame exon-skipping, providing functional evidence of their pathogenicity. MSH2 and MSH6 are co-located on Chr2p21, but the two variants segregated independently (mapped in trans) within the digenic branch, with carriers of either or both variants. Thus, MSH2 c.2006G>T and MSH6 c.3936_4001+8dup independently confer LS with differing cancer risks among family members in the same branch. Carriers of both variants have near 100% risk of transmitting either one to offspring. Nevertheless, a female carrier of both variants did not transmit either to one son, due to a germline recombination within the intervening region. Genetic diagnosis, risk stratification, and counseling for cancer and inheritance were highly individualized in this family. The finding of multiple cancer-associated variants in this pedigree illustrates a need to consider offering multicancer gene panel testing, as opposed to targeted cascade testing, as additional cancer variants may be uncovered in relatives.

Claudin-18

CONTEXT.—

Claudin-18 is expressed in some gastric cancers. Clinical trials are evaluating it as a therapeutic target.

OBJECTIVE.—

To evaluate claudin-18 expression in intestinal metaplasia, dysplasia, and adenocarcinoma of distal esophagus/gastroesophageal junction and stomach. To also evaluate claudin-18 expression in gastric and nongastric neuroendocrine tumors as a marker of gastric origin.

DESIGN.—

Samples included gastroesophageal junction with intestinal metaplasia (n = 40), dysplasia (n = 54), and adenocarcinoma (n = 20) and stomach with intestinal metaplasia (n = 79), dysplasia (n = 43), and adenocarcinoma (n = 25). Additionally, gastric (n = 40) and nongastric (n = 322) neuroendocrine tumors were included. Claudin-18 expression was evaluated for any staining as positive and by meeting clinical trial inclusion criteria (≥2+ intensity in ≥50% of tumor).

RESULTS.—

Claudin-18 staining was not significantly different across dysplasia categories in gastroesophageal junction (P = .11) or stomach (P = .12). Rate of positive staining was higher in gastroesophageal junction than stomach for intestinal metaplasia (37 of 40 [92.5%] versus 37 of 79 [46.8%]; P < .001) and high-grade dysplasia (33 of 38 [86.8%] versus 9 of 16 [56.3%]; P = .03). Intestinal metaplasia showed staining in 7 of 37 autoimmune gastritis samples (18.9%) compared with 30 of 42 without autoimmune gastritis (71.4%) (P < .001). Adenocarcinoma showed similar staining in gastroesophageal junction (15 of 20; 75.0%) and stomach (17 of 25; 68.0%) (P = .85). Eighty percent (32 of 40) of gastric neuroendocrine tumors were positive for claudin-18 expression, with 57.5% (23 of 40) meeting clinical trial inclusion criteria. Comparatively, 0.62% (2 of 322) of nongastric neuroendocrine tumors showed staining (P < .001).

CONCLUSIONS.—

Claudin-18 staining was similar in intestinal metaplasia, dysplasia, and adenocarcinoma. Claudin-18 was negative in most cases of intestinal metaplasia in autoimmune gastritis, indicating that intestinal metaplasia in this setting may differ from other forms. Claudin-18 was sensitive and specific for gastric origin in neuroendocrine tumors.

Consensus recommendations for histological criteria of autoimmune hepatitis from the International AIH Pathology Group: Results of a workshop on AIH histology hosted by the European Reference Network on Hepatological Diseases and the European Society of Pathology: Results of a workshop on AIH histology hosted by the European Reference Network on Hepatological Diseases and the European Society of Pathology

BACKGROUND & AIMS

Diagnostic histological criteria for autoimmune hepatitis (AIH) have not been clearly established. Previously published criteria focused mainly on chronic AIH, in which inflammatory changes mainly occur in portal/periportal regions and may not be applicable to acute presentation of AIH, in which inflammatory changes are typically predominantly lobular in location. International consensus criteria for the diagnosis and assessment of disease severity in both acute and chronic AIH are thus urgently needed.

METHODS

Seventeen expert liver pathologists convened at an international workshop and subsequently used a modified Delphi panel approach to establish consensus criteria for the histopathological diagnosis of AIH.

RESULTS

The consensus view is that liver biopsy should remain standard for diagnosing AIH. AIH is considered likely, if there is a predominantly portal lymphoplasmacytic hepatitis with more than mild interface activity and/or more than mild lobular hepatitis in the absence of histological features suggestive of another liver disease. AIH is also considered likely if there is predominantly lobular hepatitis with or without centrilobular necroinflammation and at least one of the following features: portal lymphoplasmacytic hepatitis, interface hepatitis or portal-based fibrosis, in the absence of histological features suggestive of another liver disease. Emperipolesis and hepatocellular rosettes are not regarded as being specific for AIH.

CONCLUSIONS

The criteria proposed in this consensus statement provide a uniform approach to the histological diagnosis of AIH, which is relevant for patients with an acute as well as a chronic presentation and to more accurately reflect the current understanding of liver pathology in AIH.

MRI-based (MAST) score accurately identifies patients with NASH and significant fibrosis

BACKGROUND & AIMS

Among the large population of patients with non-alcoholic fatty liver disease (NAFLD), identifying those with fibrotic non-alcoholic steatohepatitis (Fibro-NASH) is a clinical priority, as these patients are at the highest risk of disease progression and will benefit most from pharmacologic treatment. MRI-based proton density fat fraction (MRI-PDFF) and MR elastography (MRE) can risk-stratify patients with NAFLD by assessing steatosis and fibrosis, respectively. We developed a highly specific MRI-based score to identify patients with Fibro-NASH.

METHODS

This analysis included derivation (n = 103) and validation (n = 244) cohorts of patients who underwent MRI, liver biopsy, transient elastography, and laboratory testing for NAFLD from 2016-2020 in 2 tertiary care centers. To identify Fibro-NASH, a formula was developed based on MRI-PDFF, MRE, and a third variable with highest balanced accuracy per logistic regression. The MRI-aspartate aminotransferase (MAST) score was created and compared to NAFLD fibrosis (NFS), Fibrosis-4 (FIB-4), and FibroScan-aspartate aminotransferase (FAST) scores.

RESULTS

The MAST score demonstrated high performance and discrimination in the validation cohort (AUC 0.93; 95% CI 0.88-0.97). In the validation cohorts, the 90% specificity cut-off of 0.242 corresponded to a sensitivity of 75.0%, positive predictive value (PPV) of 50.0% and negative predictive value (NPV) of 96.5%, whereas the 90% sensitivity cut-off of 0.165 corresponded to a specificity of 72.2%, PPV of 29.4%, and NPV of 98.1%. Compared to NFS and FIB-4, MAST resulted in fewer patients having indeterminate scores and an overall higher AUC. Compared to FAST, MAST exhibited a higher AUC and overall better discrimination.

CONCLUSION

The MAST score is an accurate, MRI-serum-based score that outperforms previous scores in non-invasively identifying patients at higher risk of Fibro-NASH.

LAY SUMMARY

Identifying patients with non-alcoholic steatohepatitis and significant fibrosis - who need treatment and are at risk of clinical liver-related outcomes - is a clinical priority. We developed a more accurate score using MRI-based technologies and a laboratory blood test (aspartate aminotransferase) that outperforms previous non-invasive scores for the identification of patients at higher risk of liver disease progression.

Heterogeneity of liver fibrosis in patients with congestive hepatopathy: A biopsy and explant comparison series

PURPOSE

Patients with end-stage heart failure and concomitant irreversible liver injury may be candidates for combined heart liver transplant (CHLT). Determining appropriate candidates for CHLT is essential given organ scarcity. Transjugular liver biopsy (TJLB) is used to evaluate the severity of parenchymal liver injury in transplant candidates. In patients with congestive hepatopathy (CH), the fibrosis pattern may be heterogenous.

METHODS

We reviewed all CHLT cases between 2007 and 2017, as well as lone-heart transplant cases with post-mortem autopsy. Pre-transplant TJLB was compared to explant to assess the performance of biopsy fibrosis staging.

RESULTS

12 patients were included. Median age at time of transplant was 58 and the cohort was predominantly male (75%). Seven (64%) TJLB were predominantly stage 4 fibrosis and 4 (36%) were stage 1. Advanced fibrosis was the dominant pattern in 7 (70%) explants and 5 (50%) explants had heterogenous fibrosis. In 50% of CH cases, there was discordance between the TJLB and explant. In the autopsy cases, the TJLB and autopsy findings differed.

CONCLUSIONS

In this series of matched TJLB and explanted livers, we found variable performance of TJLB in predicting the predominant fibrosis stage present in the liver.

Evaluation of tumor mutational burden in small early hepatocellular carcinoma and progressed hepatocellular carcinoma

While researchers know that tumor mutational burden (TMB) is low in hepatocellular carcinoma (HCC), prior studies have not investigated TMB in cirrhosis, small early HCC and progressed HCC. HCC (n = 18) and cirrhosis (n = 6) cases were identified. TMB was determined by a 1.7 megabase, 409-gene next-generation sequencing panel. TMB values were defined as the number of nonsynonymous variants per megabase of sequence. There was no significant difference between cirrhosis versus small early HCC or between cohorts when stratified by size, early versus progressed, differentiation or morphology. There was a significant difference between cirrhosis and small early HCC versus progressed HCC (p = 0.045), suggesting TMB may be related to HCC progression. TMB similarities in small early HCC and background cirrhosis suggest TMB is not a useful tool for diagnosing small early HCC. Additional study is needed to address TMB in histological and molecular subsets of HCC.

Applying criteria for hepatocellular neoplasm of uncertain malignant potential reclassifies more than half of hepatocellular adenomas

OBJECTIVES

Hepatocellular adenoma (HCA) is a benign well-differentiated hepatocellular neoplasm that can be difficult to distinguish from well-differentiated hepatocellular carcinoma (HCC). The term "well-differentiated hepatocellular neoplasm of uncertain malignant potential" (HUMP) has been proposed for neoplasms resembling HCAs, but arising in atypical clinical situations (in females over 50 years old or under 15, in males, with anabolic steroid use, or in some congenital conditions), and/or with atypical pathological features (focal cytological/architectural atypia, β-catenin activation, or focal reticulin loss) insufficient for an unequivocal diagnosis of HCC.

METHODS

This study evaluated HUMP criteria on 42 previously diagnosed HCAs from 33 patients.

RESULTS

Twenty-six (62%) masses from 21 patients were classified as HUMPs. Eleven (42%) had focal cytological atypia, and two (8%) had focal architectural atypia. Four (15%) showed focal reticulin loss. Five (19%) showed evidence of β-catenin activation. Four (12%) HUMP patients were male.

CONCLUSIONS

In this series, HUMP did not correlate with an increased rate of synchronous or metachronous HCC compared to HCA. Clinical colleagues may not accept such a high rate of tumors placed in a category of "uncertain malignant potential". Additional study is warranted to refine criteria for designating well-differentiated hepatocellular neoplasms as of uncertain malignant potential.

New Names for Old Tumors

OBJECTIVES

Previous studies described "clear cell" hepatocellular carcinoma (HCC), although definitions have varied. New clear cell subtypes of HCC have been proposed, including chromophobe (C-HCC), steatohepatitic (SH-HCC), and steatotic (S-HCC), and this study assessed the utility and clinical-pathologic profile of these subtypes.

METHODS

Current histologic definitions, including 3 separate proposed definitions for SH-HCC, were applied to tumors previously characterized as clear cell HCC. Histologic and clinical variables were analyzed.

RESULTS

Of 66 HCCs, 51 (77%) were classified using modern definitions, including 34 SH-HCCs, 15 S-HCCs, and 2 C-HCCs. Compared with the most permissive SH-HCC definition, the other 2 definitions designated 30 and 25 SH-HCCs (-12% and -26% cases, respectively). Unsurprisingly, S-HCC and SH-HCC were associated with steatotic clear cells (P < .0001). S-HCC was also more typically early type and low grade (P = .0017). The remaining unclassified clear cell HCCs were associated with flocculent (rather than steatotic or optically clear) cytoplasm (P < .0001) but otherwise demonstrated no discrete clinical-pathologic profile.

CONCLUSIONS

Current definitions could be used to reclassify the majority of "clear cell" HCCs. The subtypes are significantly correlated with a few variables, suggesting valid differences of the subtypes, although additional study is warranted, particularly to standardize the definition of SH-HCC.

Seronegative autoimmune enteropathy with duodenal sparing and colonic clues in an adult female

Autoimmune enteropathy (AIE) is a rare immune disorder of the gut seldom found in adults and characterized by uncontrollable diarrhea resulting in malabsorption. While AIE is known to be pan-enteric, virtually all cases have presented with altered duodenal histology following known patterns with or without macroscopic change. We describe a unique case of seronegative AIE lacking typical duodenal manifestations in a 43-year-old female. To our knowledge, this is the first report of AIE lacking usual duodenal histologic changes, which resulted in missed diagnosis for years. Ultimately, crypt epithelial apoptosis, mononuclear inflammation of the lamina propria, and goblet cell loss of intestinal mucosa besides the duodenum clinched the diagnosis of AIE. Colonic histologic abnormalities consistent with AIE in the setting of diarrhea with malnutrition despite duodenal sparing should prompt suspicion for AIE given the pan-enteric nature of this disease.

Lymphogranuloma venereum (LGV) of the anorectum: evaluation of clinicopathological associations and the utility of a novel RNA in-situ hybridisation stain

AIMS

Recent studies from multiple global regions have reported a resurgence of lymphogranuloma venereum (LGV) proctitis, which is caused by Chlamydia trachomatis (CT). LGV proctitis is histologically indistinguishable from other forms of sexually transmitted proctitis and is difficult to differentiate from inflammatory bowel disease. While immunohistochemical stains are available for syphilis, there is no commonly available stain for the tissue identification of CT.

MATERIALS AND METHODS

From 200 positive CT nucleic acid tests (NAT) from anorectal swabs, we identified 12 patients with biopsies collected from the distal colorectum or anus within 90 days of the positive NAT. We collected basic demographic information and tabulated clinical and histological findings. We examined the performance of a novel RNA in-situ hybridisation (ISH) stain targeting CT 23s rRNA on these 12 cases and 10 controls from the anorectum.

RESULTS

All 12 patients were male; nine were HIV+, two had concurrent gonococcal infection, one had concurrent syphilis and one had cytomegalovirus co-infection. The majority of biopsies (11 of 12) showed mild or moderate acute inflammation, had a prominent lymphoplasmacytic infiltrate (eight of 11) and lacked marked crypt distortion (10 of 10). The RNA ISH stain was positive in 10 of 12 cases (sensitivity 83%). One case showed equivocal staining. No controls showed definitive positive staining (specificity 100%). One had equivocal staining.

CONCLUSION

Our series showed that anorectal LGV had similar histological findings to those of prior STI proctitis series predominantly comprised of syphilis. The novel RNA ISH stain was sensitive and specific and may show utility in differentiating types of STI proctitis.

Standardising the interpretation of liver biopsies in non-alcoholic fatty liver disease clinical trials

BACKGROUND

There is substantial variation in how histologic definitions and scoring systems of non-alcoholic fatty liver disease (NAFLD) are operationalised.

AIM

To develop a consensus-based framework for standardising histologic assessment of liver biopsies in clinical trials of NAFLD.

METHODS

An expert panel of 14 liver pathologists and three hepatologists was assembled. Using modified RAND/University of California Los Angeles appropriateness methodology, 130 items derived from literature review and expert opinion were rated by each panel member on a 1-9 scale. Disagreement was defined as ≥5 ratings in the lowest (1-3) and highest (7-9) categories. Items were classified as inappropriate (median 1-3.5 without disagreement), uncertain (median 3.5-6.5 or any median with disagreement) or appropriate (median 6.5-9 without disagreement). Survey results were discussed as a group before voting.

RESULTS

Current measures of disease activity and fibrosis may not fully capture important features of non-alcoholic steatohepatitis (NASH). Alternative methods to evaluate ballooning degeneration are needed. Panellists were uncertain whether portal inflammation, degree of steatosis and Mallory-Denk bodies are important measures of disease activity. Furthermore, it was felt that current staging systems do not capture the full spectrum of fibrosis in NASH. A consensus definition and sub-stages for bridging fibrosis are needed. The severity of perisinusoidal fibrosis should be captured at all stages. Lastly, a method to evaluate features of fibrosis regression should be developed.

CONCLUSION

The operating properties of the modifications proposed should be evaluated prospectively to determine reliability and responsiveness.

First Reported Case of a Well-Differentiated Neuroendocrine Tumor (WDNET) Arising Within Diffuse Ganglioneuromatosis (DGN) in a Patient With Neurofibromatosis Type 1 (NF-1)

Case Report

A 51-year-old female with NF-1 underwent flexible sigmoidoscopy, which revealed a 1.8-cm mass in the upper rectum. The noncircumferential mass was located predominantly at the posterior rectal wall and was suspicious for a neurofibroma. The biopsy revealed a WDNET arising in a ganglioneuroma that extended to the edges of the biopsy tissue. The patient underwent a segmental resection, and sections revealed residual grade 1 WDNET intimately admixed with DGN. The area of DGN also showed multifocal microscopic clusters of neuroendocrine cells limited to the lamina propria.

Discussion

NF-1 involves the gastrointestinal tract in 10% to 25% of affected individuals. DGN is a poorly circumscribed, frequently transmural gastrointestinal lesion composed of spindled and ganglion cells that may be seen in PTEN hamartomatous tumor syndrome, multiple endocrine neoplasia syndrome type 2B, and (less commonly) NF-1. Though malignant transformation of neurofibromas to malignant peripheral nerve sheath tumors is well documented in NF-1, malignant transformation of DGN is extremely rare. To our knowledge, this is the first reported case of a WDNET arising in DGN.

In addition to being the first reported case of WDNET in this setting, this is the first case to describe microscopic neuroendocrine cell nests in DGN. Similar proliferations have been described in the setting of inflammatory bowel disease, termed microcarcinoid or neuroendocrine cell micronests, which are not thought to have malignant potential. However, given the presence of these microscopic neuroendocrine cell nests within the larger DGN lesions and adjacent to the WDNET, we hypothesize that in the setting of NF-1, microscopic neuroendocrine cell clusters may serve as a precursor of WDNET. While this is a rare situation, these novel findings should prompt careful examination for WDNET and microscopic neuroendocrine cell nests in future cases of DGN.

Wilson disease

Wilson disease (WD) is an inherited disorder of copper metabolism. The resultant defective handling of copper results in toxic effects on the hepatocytes and increased copper in the circulation. Copper accumulates in other organ sites especially the central nervous system. WD occurs worldwide, usually between 5 and 35 years; a wider age range is now recognized. Clinical presentations are diverse and include combinations of hepatic, neurological, ophthalmic and psychiatric manifestations. Biochemical abnormalities such as serum ceruloplasmin and 24-h urinary copper excretion are important for the diagnosis but are not always abnormal in WD. They can overlap with non-WD causes. Patients may present with hepatic or neurological disease or combinations thereof. Approx. 50% of WD patients present with liver disease. Liver presentation is variable: asymptomatic abnormal liver tests, chronic hepatitis picture, cirrhosis, and acute liver failure. Similarly, the histology has several different patterns: mild nonspecific changes, steatosis or steatohepatitis, chronic hepatitis, and acute hepatitis with submassive or massive necrosis. None of these are specific for WD. Aids to the histologic diagnosis include special stains for copper and copper associated protein, and copper concentration in liver tissue. The biopsy is performed in the context of the clinical algorithms for the diagnosis of WD put forth by the clinical hepatology organizations such as the European Association for the Study of Liver Disease and the American Association for the Study of Liver Disease. The discovery of the responsible gene ATP7B has made the molecular diagnosis feasible through genetic testing and sequencing of the gene.

Methylated SEPTIN9 plasma test for colorectal cancer detection may be applicable to Lynch syndrome

OBJECTIVE

The plasma-based methylated SEPTIN9 (mSEPT9) is a colorectal cancer (CRC) screening test for adults aged 50-75 years who are at average risk for CRC and have refused colonoscopy or faecal-based screening tests. The applicability of mSEPT9 for high-risk persons with Lynch syndrome (LS), the most common hereditary CRC condition, has not been assessed. This study sought preliminary evidence for the utility of mSEPT9 for CRC detection in LS.

DESIGN

Firstly, SEPT9 methylation was measured in LS-associated CRC, advanced adenoma, and subject-matched normal colorectal mucosa tissues by pyrosequencing. Secondly, to detect mSEPT9 as circulating tumor DNA, the plasma-based mSEPT9 test was retrospectively evaluated in LS subjects using the Epi proColon 2.0 CE assay adapted for 1mL plasma using the "1/1 algorithm". LS case groups included 20 peri-surgical cases with acolonoscopy-based diagnosis of CRC (stages I-IV), 13 post-surgical metastatic CRC, and 17 pre-diagnosis cases. The control group comprised 31 cancer-free LS subjects.

RESULTS

Differential hypermethylation was found in 97.3% (36/37) of primary CRC and 90.0% (18/20) of advanced adenomas, showing LS-associated neoplasia frequently produce the mSEPT9 biomarker. Sensitivity of plasma mSEPT9 to detect CRC was 70.0% (95% CI, 48%-88%)in cases with a colonoscopy-based CRC diagnosis and 92.3% (95% CI, 64%-100%) inpost-surgical metastatic cases. In pre-diagnosis cases, plasma mSEPT9 was detected within two months prior to colonoscopy-based CRC diagnosis in 3/5 cases. Specificity in controls was 100% (95% CI 89%-100%).

CONCLUSION

These preliminary findings suggest mSEPT9 may demonstrate similar diagnostic performance characteristics in LS as in the average-risk population, warranting a well-powered prospective case-control study.

Hepatic Tm6sf2 overexpression affects cellular ApoB-trafficking, plasma lipid levels, hepatic steatosis and atherosclerosis

The human transmembrane 6 superfamily member 2 (TM6SF2) gene has been implicated in plasma lipoprotein metabolism, alcoholic and non-alcoholic fatty liver disease and myocardial infarction in multiple genome-wide association studies. To investigate the role of Tm6sf2 in metabolic homeostasis, we generated mice with elevated expression using adeno-associated virus (AAV)-mediated gene delivery. Hepatic overexpression of mouse Tm6sf2 resulted in phenotypes previously observed in Tm6sf2-deficient mice including reduced plasma lipid levels, diminished hepatic triglycerides secretion and increased hepatosteatosis. Furthermore, increased hepatic Tm6sf2 expression protected against the development of atherosclerosis in LDL-receptor/ApoB48-deficient mice. In cultured human hepatocytes, Tm6sf2 overexpression reduced apolipoprotein B secretion and resulted in its accumulation within the endoplasmic reticulum (ER) suggesting impaired ER-to-Golgi trafficking of pre-very low-density lipoprotein (VLDL) particles. Analysis of two metabolic trait-associated coding polymorphisms in the human TM6SF2 gene (rs58542926 and rs187429064) revealed that both variants impact TM6SF2 expression by affecting the rate of protein turnover. These data demonstrate that rs58542926 (E167K) and rs187429064 (L156P) are functional variants and suggest that they influence metabolic traits through altered TM6SF2 protein stability. Taken together, our results indicate that cellular Tm6sf2 level is an important determinant of VLDL metabolism and further implicate TM6SF2 as a causative gene underlying metabolic disease and trait associations at the 19p13.11 locus.

A Limited Immunohistochemical Panel Can Subtype Hepatocellular Adenomas for Routine Practice

OBJECTIVES

β-Catenin-activated hepatocellular adenomas have an elevated risk of harboring foci of hepatocellular carcinoma. Inflammatory adenomas also have an increased propensity for malignant transformation and are associated with a systemic inflammatory syndrome. Patients with these two adenoma subtypes benefit from excision. We assessed whether β-catenin-activated and inflammatory adenomas could be identified using a limited immunohistochemical panel.

METHODS

Forty-six adenomas were assessed by morphology and β-catenin, serum amyloid A, and glutamine synthetase immunostains.

RESULTS

Morphologic examination produced a morphologic working diagnosis of inflammatory adenoma in 25 (54%) of 46 cases, β-catenin-activated adenoma in three (7%) of 46 cases, and 18 (39%) of 46 cases of other adenomas. After immunohistochemical staining, the morphologic diagnosis was confirmed in 15 (33%) of 46 and changed in 20 (43%) of 46, for a final distribution of 16 (35%) of 46 inflammatory adenomas, four (9%) of 46 β-catenin-activated adenomas, seven (15%) of 46 β-catenin-activated inflammatory adenomas, and 19 (41%) of 46 other adenomas.

CONCLUSIONS

Inflammatory and β-catenin-activated adenomas were readily identified by immunostaining patterns. These findings reinforce the necessity of immunohistochemistry in classifying adenomas, as assessing morphology alone often provided inaccurate subclassification. β-Catenin-activated and inflammatory adenomas can be accurately diagnosed using only a limited panel of widely available immunostains.

Comparison of endoscopic ultrasound guided fine needle aspiration and PET/CT in preoperative diagnosis of pancreatic adenocarcinoma

BACKGROUND

Endoscopic ultrasound guided fine needle aspiration (EUS-FNA) is the procedure of choice to investigate and sample pancreatic masses for the preoperative diagnosis of pancreatic ductal adenocarcinoma (PDAC). The role of ¹⁸fluoro-deoxyglucose positron emission tomography/computed tomography (PET/CT) in PDAC is debated. This study evaluates the role of EUS-FNA as compared to PET/CT in the preoperative evaluation of PDAC.

METHODS

Preoperative evaluation by PET/CT and EUS-FNA was performed on 25 patients with pancreatic solid lesions, who underwent a subsequent Whipple procedure or partial pancreatic resection.

RESULTS

This series included 19 PDACs and 6 non-PDACs including 1 metastatic breast ductal adenocarcinoma, 2 low grade neuroendocrine tumors, 2 chronic pancreatitis and 1 gastrointestinal tumor abutting the pancreas. EUS-FNA correctly diagnosed 18 of 19 PDACs, 1 metastatic breast ductal adenocarcinoma and all 5 of the other non-PDAC cases. One case of well differentiated PDAC was negative on EUS-FNA. PET/CT provided excellent size and was positive in 14 of 19 PDACs and the metastatic breast ductal adenocarcinoma. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy for EUS-FNA in diagnosis of selected pancreatic tumors were 91%, 100%, 100%, 50% and 92%, respectively, while they were 65%, 100%, 100%, 20% and 68% for PET/CT, respectively.

CONCLUSIONS

Compared to PET/CT, EUS-FNA has a higher sensitivity and accuracy for preoperative diagnosis of PDAC. However, PET/CT provides excellent size, volume and stage information. A combination of both PET/CT and EUS will better help guide diagnosis and treatment of pancreatic adenocarcinoma.

Association of hyaluronan accumulation with clinical-pathologic features in pancreatic ductal adenocarcinomas

322

Background: Pancreatic ductal adenocarcinoma (PDA) is characterized by marked stromal fibrosis and hyaluronan (HA) accumulation. Degradation of stromal HA using PEGylated recombinant human hyaluronidase (PEGPH20) in combination with anti-cancer therapeutics has demonstrated increased efficacy in preclinical models. This study used an exploratory prototype HA assay to assess HA and to explore the association of HA status with clinical and pathological variables. Methods: Sixty-four PDA samples from 49 patients treated with gemcitabine and nab-paclitaxel were stained for HA using a prototype histochemical binding assay. The tumor extracellular matrix staining for HA at any intensity above background as a proportion of the total tumor surface area was recorded. Cases were categorized as HA-high (HA score of ≥50%) or HA-low (HA score of <50%). Subgroup analyses were also performed in paired pre- and post-chemotherapy samples. Results: Twenty-six of 49 (53%) patients were determined to be HA-high. HA-high status was significantly associated with pN1 (positive node) status (p<0.001) and well/moderate differentiation (p<0.001). No correlation of HA status was observed with sex, race, primary tumor location, pT (tumor) stage, lymph-vascular invasion, pathologic stage, or initial CA19-9 levels. No trend in HA status was observed comparing pre- and post-chemotherapy specimens (n=5). Conclusions: HA status was significantly associated with nodal stage and grade.

Cadherin-11 Is a Cell Surface Marker Up-Regulated in Activated Pancreatic Stellate Cells and Is Involved in Pancreatic Cancer Cell Migration

Chronic pancreatitis is a prominent risk factor for the development of pancreatic ductal adenocarcinoma. In both conditions, the activation of myofibroblast-like pancreatic stellate cells (PSCs) plays a predominant role in the formation of desmoplastic reaction through the synthesis of connective tissue and extracellular matrix, inducing local pancreatic fibrosis and an inflammatory response. Yet the signaling events involved in chronic pancreatitis and pancreatic cancer progression and metastasis remain poorly defined. Cadherin-11 (Cad-11, also known as OB cadherin or CDH11) is a cell-to-cell adhesion molecule implicated in many biological functions, including tissue morphogenesis and architecture, extracellular matrix-mediated tissue remodeling, cytoskeletal organization, epithelial-to-mesenchymal transition, and cellular migration. In this study, we show that, in human chronic pancreatitis and pancreatic cancer tissues, Cad-11 expression was significantly increased in PSCs and pancreatic cancer cells. In particular, an increased expression of Cad-11 can be detected on the plasma membrane of activated PSCs isolated from chronic pancreatitis tissues and in pancreatic cancer cells metastasized to the liver. Moreover, knockdown of Cad-11 in cancer cells reduced pancreatic cancer cell migration. Taken together, our data underline the potential role of Cad-11 in PSC activation and pancreatic cancer metastasis.

Adjuvant sunitinib following chemoradiotherapy and surgery for locally advanced esophageal cancer: a phase II trial

The prognosis for locally advanced esophageal cancer is poor despite the use of trimodality therapy. In this phase II study, we report the feasibility, tolerability and efficacy of adjuvant sunitinib. Included were patients with stage IIa, IIB or III cancer of the thoracic esophagus or gastroesophageal junction. Neoadjuvant therapy involved Irinotecan (65 mg/m² ) + Cisplatin (30 mg/m² ) on weeks 1 and 2, 4 and 5, 7 and 8 with concurrent radiation (50Gy/25 fractions) on weeks 4-8. Sunitinib was commenced 4-13 weeks after surgery and continued for one year. Sixty-one patients were included in the final analysis, 36 patients commenced adjuvant sunitinib. Fourteen patients discontinued sunitinib due to disease recurrence (39%) within the 12-month period, 12 (33%) discontinued due to toxicity, and 3 (8%) requested cessation of therapy. In the overall population, median survival was 26 months with a 2 and 3-year survival rate of 52% and 35%, respectively. The median survival for the 36 patients treated with sunitinib was 35 months and 2-year survival probability of 68%. In a historical control, a prior phase II study with the same trimodality therapy (n = 43), median survival was 36 months, with a 2-year survival of 67%. Initiation of adjuvant sunitinib is feasible, but poorly tolerated, with no signal of additional benefit over trimodality therapy for locally advanced esophageal cancer.

Plasma phospholipids and fatty acid composition differ between liver biopsy-proven nonalcoholic fatty liver disease and healthy subjects

Background:

There is growing evidence that nonalcoholic fatty liver disease (NAFLD) is associated with perturbations in liver lipid metabolism. Liver phospholipid and fatty acid composition have been shown to be altered in NAFLD. However, detailed profiles of circulating lipids in the pathogenesis of NAFLD are lacking.

Objective:

Therefore, the objective of the present study was to examine circulating lipids and potential mechanisms related to hepatic gene expression between liver biopsy-proven simple steatosis (SS), nonalcoholic steatohepatitis (NASH) and healthy subjects.

Subjects:

Plasma phospholipid and fatty acid composition were determined in 31 healthy living liver donors as healthy controls (HC), 26 patients with simple hepatic steatosis (SS) and 20 with progressive NASH. Hepatic gene expression was analyzed by Illumina microarray in a subset of 22 HC, 16 SS and 14 NASH.

Results:

Concentrations of phosphatidylethanolamine (PE) increased relative to disease progression, HC<SS<NASH (170<210<250 μg ml⁻¹), and was significantly different (P<0.05) between HC and NASH. Circulating phosphatidylserine (PS) and phosphatidylinositol were higher in SS and NASH compared with HC (P<0.05), but there was no difference between SS and NASH. Fatty acid composition of phospholipids was also remodeled. In particular, docosahexaenoic and arachidonic acid were higher (P<0.05) in SS and NASH relative to HC in PS. Differentially expressed hepatic genes included ETNK1 and PLSCR1 that are involved in PE synthesis and PS transport, respectively.

Conclusions:

The present study demonstrates that there is a disruption in phospholipid metabolism that is present in SS, but more pronounced in NASH. Intervention studies targeted at lipid metabolism could benefit SS and NASH.

Quantitative imaging for development of companion diagnostics to drugs targeting HGF/MET

The limited clinical success of anti-HGF/MET drugs can be attributed to the lack of predictive biomarkers that adequately select patients for treatment. We demonstrate here that quantitative digital imaging of formalin fixed paraffin embedded tissues stained by immunohistochemistry can be used to measure signals from weakly staining antibodies and provides new opportunities to develop assays for detection of MET receptor activity. To establish a biomarker panel of MET activation, we employed seven antibodies measuring protein expression in the HGF/MET pathway in 20 cases and up to 80 cores from 18 human cancer types. The antibodies bind to epitopes in the extra (EC)- and intracellular (IC) domains of MET (MET4^EC, SP44_MET^IC, D1C2_MET^IC), to MET-pY1234/pY1235, a marker of MET kinase activation, as well as to HGF, pSFK or pMAPK. Expression of HGF was determined in tumour cells (T_HGF) as well as in stroma surrounding cancer (St_HGF). Remarkably, MET4^EC correlated more strongly with pMET (r = 0.47) than SP44_MET^IC (r = 0.21) or D1C2_MET^IC (r = 0.08) across 18 cancer types. In addition, correlation coefficients of pMET and T_HGF (r = 0.38) and pMET and pSFK (r = 0.56) were high. Prediction models of MET activation reveal cancer-type specific differences in performance of MET4^EC, SP44_MET^IC and anti-HGF antibodies. Thus, we conclude that assays to predict the response to HGF/MET inhibitors require a cancer-type specific antibody selection and should be developed in those cancer types in which they are employed clinically.

The State of the Art in Colorectal Cancer Molecular Biomarker Testing

The number of molecular biomarkers to inform treatment decisions in patients with metastatic colorectal cancer (mCRC) continues to expand and with it the methodologies that can be employed to evaluate these biomarkers. Beyond standard diagnostic and prognostic biomarkers, such as those used for Lynch syndrome, mutations in KRAS exon 2 are well established as predictive for lack of response to the antiepidermal growth factor receptor therapies panitumumab and cetuximab. Recent studies have extended these findings by demonstrating that mutations in KRAS exons 3 and 4 and in NRAS exons 2, 3, and 4 (with all KRAS and NRAS mutations collectively referred to as RAS) are also predictive for treatment outcomes among patients with mCRC receiving panitumumab and cetuximab in combination with chemotherapy or as monotherapy. Consequently, evaluation of these additional loci has been incorporated into current clinical guidelines, and pathologists will need to develop testing procedures and algorithms to reliably and rapidly evaluate RAS status. With the increased number of mutations that must be examined to evaluate the status of RAS and other emerging biomarkers, next-generation sequencing technologies are likely to become increasingly important in mCRC testing. This review describes new considerations for pathologists that have arisen as a consequence of the incorporation of additional biomarker testing into clinical practice for mCRC.

Hypoxia after transarterial chemoembolization may trigger a progenitor cell phenotype in hepatocellular carcinoma

AIMS

To test the hypothesis that the hypoxia marker carbonic anhydrase IX (CAIX), and the cholangiocytic/progenitor markers cytokeratin (CK) 19 and epithelial cell adhesion molecule (EpCAM), may be expressed in areas of hypoxia in hepatocellular carcinoma (HCC) after transarterial chemoembolization (TACE).

METHODS AND RESULTS

Immunohistochemistry for CAIX, CK19 and EpCAM (BerEP4) was performed in 57 HCCs, including 40 residual/recurrent tumours adjacent to the TACE treatment site and 17 untreated tumours from the same 40 patients. CAIX was exxpressed in 19 of 40 residual/recurrent HCCs and in two of 17 untreated HCCs. The rate of CAIX immunoreactivity in the treated tumours was significantly higher than that in the non-treated tumours (47.5% versus 11.8%, P = 0.015). CK19 and EpCAM were expressed in six of 19 and in seven of 19 CAIX-positive TACE-treated HCCs, respectively, but were not expressed in CAIX-negative tumours or untreated tumours. There were significant associations between CK19 and CAIX immunoreactivity, and between EpCAM and CAIX immunoreactivity (P = 0.007 and P = 0.003, respectively). Double staining of CAIX and CK19 showed co-localization of both proteins in five of six cases. Three of seven EpCAM-positive tumours were also positive for CK19.

CONCLUSIONS

Hypoxia may trigger the expression of proteins that are normally associated with cholangiocytic/progenitor cell differentiation, suggesting that TACE paradoxically causes an aggressive tumour phenotype.

Degree of tumor shrinkage following neoadjuvant chemoradiotherapy: a potential predictor for complete pathological response in esophageal cancer?

Neoadjuvant chemoradiotherapy (CRT) before surgery results in a pathological complete response (pCR) rate in about 1/3 of the patients, which is correlated with survival. It was hypothesized that volumetric tumor response to CRT would correlate with outcomes. Patients who completed trimodality therapy, where planning, pre-, and post-CRT computed tomography scans were available, and pathology was reviewed by a central pathologist, were eligible for analysis. Absolute and relative tumor volume change pretreatment and post-treatment were correlated with pCR, locoregional recurrence (LRR), disease-free survival, and overall survival. Fifty-six patients were analyzed. pCR was observed in 30% of patients. Median follow up was 20.3 (range 4-89) months. The 2- and 4-year overall survival was 61.3% (95% confidence interval [CI]: 45-74) and 25.0% (95%CI: 11-41); proportion disease free was 32.1% (95% CI: 19-46) and 20.6% (9-36) at 2 and 4 years, respectively. The median relative volume reduction was 17% (95% CI: -24, -3%). Using 20% as the criteria, the proportion of patients with pCR of ≥20% versus <20% was 13/25 (52%) versus 4/31 (13%) for those who did not (odds ratio 7.3; 95% CI: 2-27). The LRR at 2 and 4 years were 29.5% (95% CI: 16-43) and 36.2% (95% CI: 23-50). The relative tumor reduction ≥20% was significantly correlated with LRR (hazard ratio 0.24; 95% CI: 0.07-0.8; p 0.02) at 2 and 4 years, respectively. Relative tumor volume reduction following CRT is correlated with pCR and LRR. Further investigations are warranted to examine the effect of volume change, alone or in conjunction with other factors as potential predictors for pathological response.

(18)F-FDG-PET/CT in assessing response to neoadjuvant chemoradiotherapy for potentially resectable locally advanced esophageal cancer

PURPOSE

To correlate metabolic response to neoadjuvant chemoradiotherapy (NACR) on FDG-PET/CT using PERCIST-based criteria to pathologic and clinical response, and survival in patients with locally advanced esophageal cancer (LAEC).

MATERIALS AND METHODS

Forty-five patients with LAEC underwent PET/CT at baseline and after NACR. Tumors were evaluated using PERCIST (PET response criteria in solid tumors)-based criteria including SUL, SUL tumor/liver ratio, % change in SUL. These parameters were compared to pathology regression grade (PRG), clinical response (including residual or new disease beyond the surgical specimen), and overall survival.

RESULTS

On surgical pathology, there was complete or near-complete regression of tumor in 51.1 %, partial response in 42.2 %, and lack regression in 4.4 %. One patient (2.2 %) had progression of disease on imaging and did not undergo surgical resection. None of the baseline PET parameters had significant correlation to pathology regression grade or clinical response. On follow-up, a positive correlation was found between post-therapy SUL ratio, %∆ SUL and %∆ SUL ratio and clinical response (p = 0.025, 0.035, 0.030, respectively). A weak correlation was found between post-therapy SUL ratio to PRG (p = 0.049). A strong correlation was found between the metabolic response score and PRG (p = 0.002) as well as between metabolic response and clinical response (p < 0.001).

CONCLUSION

PERCIST-based metabolic response assessment to NACR in LAEC may correlate with clinical outcome and survival.

Identification of driver genes in hepatocellular carcinoma by exome sequencing

Genetic alterations in specific driver genes lead to disruption of cellular pathways and are critical events in the instigation and progression of hepatocellular carcinoma (HCC). As a prerequisite for individualized cancer treatment, we sought to characterize the landscape of recurrent somatic mutations in HCC. We performed whole-exome sequencing on 87 HCCs and matched normal adjacent tissues to an average coverage of 59×. The overall mutation rate was roughly two mutations per Mb, with a median of 45 nonsynonymous mutations that altered the amino acid sequence (range, 2-381). We found recurrent mutations in several genes with high transcript levels: TP53 (18%); CTNNB1 (10%); KEAP1 (8%); C16orf62 (8%); MLL4 (7%); and RAC2 (5%). Significantly affected gene families include the nucleotide-binding domain and leucine-rich repeat-containing family, calcium channel subunits, and histone methyltransferases. In particular, the MLL family of methyltransferases for histone H3 lysine 4 were mutated in 20% of tumors.

CONCLUSION

The NFE2L2-KEAP1 and MLL pathways are recurrently mutated in multiple cohorts of HCC.

Abstract 4598: Identification of driver genes in hepatocellular carcinoma by exome sequencing

Genetic alterations in specific driver genes lead to disruption of cellular pathways and are critical events in the instigation and progression of hepatocellular carcinoma. As a prerequisite for individualized cancer treatment, we sought to characterize the landscape of recurrent somatic mutations in hepatocellular carcinoma. We performed whole exome sequencing on 87 hepatocellular carcinomas and matched normal adjacent tissues to an average coverage of 59x. The overall mutation rate was roughly 2.5 mutations per Mb, with a median of 45 non-synonymous mutations that altered the amino acid sequence (range 2 to 381). We found recurrent mutations in several genes with high transcript levels: TP53 (20%), CTNNB1 (15%), IGSF3 (9%) and KEAP1 (8%). Significantly affected gene families include the nucleotide-binding domain and leucine rich repeat containing family, calcium channel subunits, and histone methyltransferases. In particular, the MLL family of methyltransferases for histone H3 lysine 4 were mutated in 20% of tumors. Clinical data demonstrated significantly decreased disease-free survival in tumors with p53 mutations (p=0.006) and a trend was observed towards higher rates of recurrence and shorter disease free survival among MLL mutation carriers. The NFE2L2-KEAP1 and MLL pathways are recurrently mutated in multiple cohorts of hepatocellular carcinoma. The elucidation of genetic changes in HCC will enhance our understanding of hepatocarcinogenesis and influence disease prognosis and therapy.

Citation Format: Sean P. Cleary, William R. Jeck, Xiaobei Zhao, Sara R. Selitsky, Gleb L. Savich, Ting-Xu Tan, Michael C. Wu, Gad Getz, Michael S. Lawrence, Joel S. Parker, Jinyu Li, Scott Powers, Hyeja Kim, Sandra E. Fischer, Maha Guindi, Anand Ghanekar, Derek Y. Chiang. Identification of driver genes in hepatocellular carcinoma by exome sequencing. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4598. doi:10.1158/1538-7445.AM2013-4598

Nonalcoholic fatty liver disease is associated with lower hepatic and erythrocyte ratios of phosphatidylcholine to phosphatidylethanolamine

Nonalcoholic fatty liver disease (NAFLD) is associated with altered hepatic lipid composition. Animal studies suggest that the hepatic ratio of phosphatidylcholine (PC) to phosphatidylethanolamine (PE) contributes to steatogenesis and inflammation. This ratio may be influenced by dysregulation of the PE N-methyltransferase (PEMT) pathway or by a low-choline diet. Alterations in the liver may also influence lipid composition in circulation such as in erythrocytes, which therefore may have utility as a biomarker of hepatic disease. Currently, no study has assessed both liver and erythrocyte PC/PE ratios in NAFLD. The aim of this study was to compare the PC/PE ratio in the liver and erythrocytes of patients with simple steatosis (SS) or nonalcoholic steatohepatitis (NASH) with that of healthy controls. PC and PE were measured by mass spectrometry in 28 patients with biopsy-proven NAFLD (14 SS, 14 NASH) and 9 healthy living liver donors as controls. The hepatic PC/PE ratio was lower in SS patients (median [range]) (1.23 [0.27-3.40]) and NASH patients (1.29 [0.77-3.22]) compared with controls (3.14 [2.20-3.73]); both p < 0.001) but it was not different between SS and NASH. PC was lower and PE higher in the liver of SS patients compared with controls, whereas in NASH patients only PE was higher. The PC/PE ratio in erythrocytes was also lower in SS and NASH patients compared with controls because of lower PC in both patient groups. PE in erythrocytes was not different among the groups. In conclusion, NAFLD patients have a lower PC/PE ratio in the liver and erythrocytes than do healthy controls, which may play a role in the pathogenesis. The underlying mechanisms require further investigation.

Up-front hepatic resection for metastatic colorectal cancer results in favorable long-term survival

BACKGROUND

Hepatic metastasis from colorectal cancer (CRC) is best managed with a multimodal approach; however, the optimal timing of liver resection in relation to administration of perioperative chemotherapy remains unclear. Our strategy has been to offer up-front liver resection for patients with resectable hepatic metastases, followed by post-liver resection chemotherapy. We report the outcomes of patients based on this surgical approach.

METHODS

A retrospective review of all patients undergoing liver resection for CRC metastases over a 5-year period (2002-2007) was performed. Associations between clinicopathologic factors and survival were evaluated by the Cox proportional hazard method.

RESULTS

A total of 320 patients underwent 336 liver resections. Median follow-up was 40 (range 8-80) months. The majority (n=195, 60.9%) had metachronous disease, and most patients (n=286, 85%) had a major hepatectomy (>3 segments). Thirty-six patients (11%) received preoperative chemotherapy, predominantly for downstaging unresectable disease. Ninety-day mortality was 2.1%, and perioperative morbidity occurred in 68 patients (20.2%). Actual disease-free survival at 3 and 5 years was 46.2% and 42%, respectively. Actual overall survival (OS) at 3 and 5 years was 63.7% and 55%, respectively. Multivariate analysis identified four factors that were independently associated with differences in OS (hazard ratio; 95% confidence interval): size of metastasis>6 cm (2.2; 1.3-3.5), positive lymph node status of the primary CRC (N1 (2.0; 1.0-3.8), N2 (2.4; 1.2-4.9)), synchronous disease (2.1; 1.3-3.5), and treatment with chemotherapy after liver resection (0.42; 0.23-0.75).

CONCLUSIONS

Up-front surgery for patients with resectable CRC liver metastases, followed by chemotherapy, can lead to favorable OS.

MicroRNA expression profiling of esophageal cancer before and after induction chemoradiotherapy

BACKGROUND

The prognosis for esophageal cancer is poor but may be improved by neoadjuvant therapy. A complete pathologic response (pCR) is associated with improved survival. We conducted a study to profile the expression of microRNAs (miRNAs) in esophageal cancer before and after induction therapy. Our aims were to identify those miRNAs that are differentially regulated after induction therapy and attempt to describe a miRNA pattern that could predict pCR.

METHODS

Total RNA was extracted from pretreatment and posttreatment specimens from 25 patients who underwent trimodal therapy using concurrent irinotecan/cisplatin and radiotherapy followed by surgical treatment. miRNAs were labeled and hybridized to the Illumina miRNA BeadChip microarray (Illumina, Inc, San Diego, CA). Expression data was quantified using BeadStudio software (Illumina), using a cutoff for significant gene differences of p less than 0.05 with a 2-fold difference in expression. Survival analysis was performed using SPSS, version 18 (SPSS, Inc, Chicago, IL).

RESULTS

Using pretreatment biopsy specimens, 71 miRNAs were significantly different between pCR and non-pCR groups. Of these, 5 miRNAs were greater than 2-fold differentially regulated, including miR-296, recently shown to be of prognostic significance in esophageal carcinoma. After induction therapy, 568 miRNAs were found to be significantly upregulated or downregulated, 111 of which had a 2-fold difference. Patients with high levels of miR-135b or miR-145 in the posttreatment biopsy specimens had significantly shorter median disease-free survival (DFS) than did those with low levels (11.5 versus 5.1 months; p=0.04; 11.5 versus 2.8 months; p=0.03).

CONCLUSIONS

miRNA expression profiling of pretreatment biopsy specimens revealed 5 miRNAs differentially expressed in patients with pCR compared with patients without pCR. We have also identified 111 miRNAs significantly upregulated or downregulated after induction therapy, some of which may be predictive of outcome. Further study of these miRNAs may elucidate a novel understanding of mechanisms of resistance to chemotherapy or radiotherapy.