Enhancing Hepatic MBOAT7 Expression in Mice With Nonalcoholic Steatohepatitis.

BACKGROUND AND AIMS: Polymorphisms near the membrane bound O-acyltransferase domain containing 7 (MBOAT7) genes are associated with worsened nonalcoholic fatty liver (NASH), and nonalcoholic fatty liver disease (NAFLD)/NASH may decrease MBOAT7 expression independent of these polymorphisms. We hypothesized that enhancing MBOAT7 function would improve NASH. METHODS: Genomic and lipidomic databases were mined for MBOAT7 expression and hepatic phosphatidylinositol (PI) abundance in human NAFLD/NASH. Male C57BL6/J mice were fed either choline-deficient high-fat diet or Gubra Amylin NASH diet and subsequently infected with adeno-associated virus expressing MBOAT7 or control virus. NASH histological scoring and lipidomic analyses were performed to assess MBOAT7 activity, hepatic PI, and lysophosphatidylinositol (LPI) abundance. RESULTS: Human NAFLD/NASH decreases MBOAT7 expression and hepatic abundance of arachidonate-containing PI. Murine NASH models display subtle changes in MBOAT7 expression, but significantly decreased activity. After MBOAT7 overexpression, liver weights, triglycerides, and plasma alanine and aspartate transaminase were modestly improved by MBOAT7 overexpression, but NASH histology was not improved. Despite confirmation of increased activity with MBOAT7 overexpression, content of the main arachidonoylated PI species was not rescued by MBOAT7 although the abundance of many PI species was increased. Free arachidonic acid was elevated but the MBOAT7 substrate arachidonoyl-CoA was decreased in NASH livers compared to low-fat controls, likely due to the decreased expression of long-chain acyl-CoA synthetases. CONCLUSION: Results suggest decreased MBOAT7 activity plays a role in NASH, but MBOAT7 overexpression fails to measurably improve NASH pathology potentially due to the insufficient abundance of its arachidonoyl-CoA substrate.

Adipose-targeted SWELL1 deletion exacerbates obesity- and age-related nonalcoholic fatty liver disease.

Healthy expansion of adipose tissue is critical for the maintenance of metabolic health, providing an optimized reservoir for energy storage in the form of triacylglycerol-rich lipoproteins. Dysfunctional adipocytes that are unable to efficiently store lipid can result in lipodystrophy and contribute to nonalcoholic fatty liver disease (NAFLD) and metabolic syndrome. Leucine-rich repeat containing protein 8a/SWELL1 functionally encodes the volume-regulated anion channel complex in adipocytes, is induced in early obesity, and is required for normal adipocyte expansion during high-fat feeding. Adipose-specific SWELL1 ablation (Adipo KO) leads to insulin resistance and hyperglycemia during caloric excess, both of which are associated with NAFLD. Here, we show that Adipo-KO mice exhibited impaired adipose depot expansion and excess lipolysis when raised on a variety of high-fat diets, resulting in increased diacylglycerides and hepatic steatosis, thereby driving liver injury. Liver lipidomic analysis revealed increases in oleic acid-containing hepatic triacylglycerides and injurious hepatic diacylglyceride species, with reductions in hepatocyte-protective phospholipids and antiinflammatory free fatty acids. Aged Adipo-KO mice developed hepatic steatosis on a regular chow diet, and Adipo-KO male mice developed spontaneous, aggressive hepatocellular carcinomas (HCCs). These data highlight the importance of adipocyte SWELL1 for healthy adipocyte expansion to protect against NAFLD and HCC in the setting of overnutrition and with aging.

Solitary Intracranial Plasmacytoma of the Brain Treated With Primary Radiation Therapy.

We present a rare case of a solitary intracranial plasmacytoma of the brain parenchyma in a 49-year-old female who presented with neck pain/headache, paresthesias, and auditory hallucinations. A workup revealed a solitary left parietal lobe brain lesion and a biopsy demonstrated a plasma cell infiltrate consistent with an extramedullary plasmacytoma. A complete workup for multiple myeloma was negative. As opposed to surgical resection and adjuvant radiation therapy (RT), as described in prior case reports in the literature, this patient was managed with definitive local RT alone to 50 Gy in 25 fractions. Six months following primary RT completion, the patient's presenting symptoms completely resolved and follow-up imaging revealed regression of the primary tumor. To our knowledge, this is the first reported case of a solitary extramedullary plasmacytoma of the brain treated with localized definitive RT alone.

A Unique Presentation of Metastatic Gallbladder Carcinoma.

Gallbladder carcinoma can be challenging to diagnose and treat and usually leads to poor outcome, due to its aggressive nature and the nonspecific clinical presentation at early stage. We describe an interesting case of a 60-year-old female who presented with stage 3 appendiceal carcinoma after appendectomy was performed outside hospital. Further imaging workup demonstrated enlarged ovarian cysts and porcelain gallbladder. Upon exploration, she was found to have carcinomatosis and we proceeded with cytoreductive surgery (CRS) and hyperthermic intraperitoneal therapy (HIPEC). Final pathology demonstrated carcinoma from gallbladder primary.

NAFLD: Reporting Histologic Findings in Clinical Practice.

The role of liver biopsy in NASH has evolved along with the increased recognition of the significance of this disease, and the unmet medical need it presents. Drug development and clinical trials are rapidly growing, as are noninvasive tests for markers of steatosis, inflammation, injury, and fibrosis. Liver biopsy evaluation remains necessary for both drug development and clinical trials as the most specific means of diagnosis and patient identification for appropriate intervention. This White Paper, sponsored by the American Association for the Study of Liver Disease NASH Task Force, is a focused review of liver biopsy evaluation in fatty liver disease in subjects with presumed NAFLD for practicing clinical hepatologists and pathologists. The goal is to provide succinct and specific means for reporting the histopathologic elements of NASH, distinguishing NASH from nonalcoholic fatty liver without steatohepatitis, and from alcohol-associated steatohepatitis when possible. The discussion includes the special situations of NASH in advanced fibrosis or cirrhosis, and in the pediatric population. Finally, there is discussion of semiquantitative methods of evaluation of lesions of "disease activity" and fibrosis. Tables are presented for scoring and a suggested model for final reporting. Figures are presented to highlight the histopathologic elements of NASH.

Expression of CDX2 and Thyroid Transcription Factor-1 in Oropharyngeal Undifferentiated Carcinomas: A Potential Diagnostic Pitfall.

Oropharyngeal undifferentiated carcinomas are rare and most are human papillomavirus related. Morphologically, they overlap with undifferentiated carcinomas from other organ sites, including the nasopharynx, lung, and gastrointestinal tract. Most have lymph node metastases at presentation and, especially when initially encountered in a lymph node, immunostains may be performed to determine the most likely primary site. We recently reviewed a case in consultation that strongly and diffusely expressed both thyroid transcription factor-1 (TTF-1, SPT24 clone) and CDX2, 2 widely used markers that are considered relatively lineage specific for lung/thyroid and intestinal differentiation, respectively. Unexpected expression of these markers could be misleading. However, they have not been previously assessed in oropharyngeal undifferentiated carcinoma. Here, we performed immunohistochemistry for CDX2 and TTF-1 (8G7G3/1 clone) on primary tumors and/or lymph node metastases from 11 in-house patients with previously characterized undifferentiated carcinoma of the oropharynx from 1992 to 2008. All were male with an average age of 56.7 years, and 5 (46%) initially presented with a neck mass. All were Epstein-Barr virus negative and 9 (82%) were human papillomavirus and p16 positive. CDX2 was positive in 6 of the 11 (55%) cases. However, staining was generally weak to moderate and/or nondiffuse. TTF-1 was negative in all the in-house cases and showed only rare, weakly positive cells in the consult case when TTF-1 was repeated using the 8G7G3/1 clone. Thus, CDX2 immunoreactivity is common, whereas TTF-1 expression is rare in oropharyngeal undifferentiated carcinomas. As a result, one should not rely on CDX2 as evidence of intestinal differentiation or origin in metastatic undifferentiated carcinomas in the neck, particularly when staining is not strong and diffuse. In addition, TTF-1 should be interpreted with caution especially when using the SPT24 clone.

Pancreatic Neuroendocrine Tumors: Computed Tomography Enhancement, But Not Histological Grade, Correlates With Tumor Aggression.

OBJECTIVES: The aims of this study were to assess computed tomography enhancement of pancreatic neuroendocrine tumors (NETs), determine correlation with histological vascularity and fibrosis, and identify a biomarker for tumor aggression. METHODS: The arterial and venous enhancement of NET was calculated on computed tomography for 56 patients. Tumor size and vascularity/fibrosis were assessed. Tumor aggression was grouped by World Health Organization and Hochwald grade and the presence of metastases. Variables were assessed for correlation. Groups were compared using t test/Wilcoxon rank sum test. RESULTS: Arterial enhancement and dynamic washout (r = 0.35, P = 0.02; r = 0.34, P = 0.02, respectively) correlate with vascularity. There is inverse correlation between vascularity and fibrosis (r = -0.62, P < 0.001), but no correlation between enhancement and fibrosis. Metastatic NET had less arterial (mean, -2 [standard deviationi {SD}, 27.1] Hounsfield unit [HU]; 35.7 [SD, 57.5] HU; P = 0.01) and venous (12.6 [SD, 14.4] HU; 29.2 [SD, 38.3] HU; P = 0.04) enhancement and less washout (8.5 [SD, 18.5] HU; 26.8 [SD, 30] HU, P = 0.02) compared with nonmetastatic NET. These differences were not present when comparing by tumor grade. Arterial hypoenhancement was the only significant predictor of metastases. CONCLUSIONS: Aggressive tumors, as determined by metastases, but not histological grade, enhance less than nonmetastatic tumors.

Assessment of disease aggression in cystic pancreatic neuroendocrine tumors: A CT and pathology correlation study.

BACKGROUND/OBJECTIVES: There are inconsistencies in the literature regarding the clinical significance of cystic components in pancreatic neuroendocrine tumors (NET). This may be related to differences in the identification of cystic NET through imaging and/or pathology. Tumors may also be microscopically or macroscopically cystic. Our primary objective is to determine radiology-pathology correlation for the identification of cystic components. Our secondary objective is to determine if cystic components are associated with indices of tumor aggression. METHODS: 60 tumors with correlative surgical pathology were assessed retrospectively for cystic components on CT and pathology. Tumor was categorized as solid or cystic on CT and pathology. If cystic on pathology, cystic components were categorized as macroscopic or microscopic. Cystic components were estimated as <50% and ≥50% tumor volume. WHO/Hochwald grade and presence of metastases were used to stratify disease aggression. Associations were tested with Chi square/Fisher's exact test and differences were tested with t-test/Wilcoxon rank sums test. RESULTS: There is moderate agreement between CT and histology for presence of cystic components. Discrepancies were mostly attributable to the presence of microscopic cystic components in tumors appearing solid on CT. There was no difference in size between cystic and solid tumors on CT or pathology. No association between CT-determined cystic components and tumor grade was found. Tumors with cystic components (cystic by CT, and macroscopically cystic by pathology) demonstrated less association with metastases than solid tumors. CONCLUSIONS: Cystic components, comprising ≥50% of the tumor by CT and observed macroscopically on pathology, are associated with less aggressive disease.

Jaundice: an important, poorly recognized risk factor for diminished survival in patients with adenocarcinoma of the head of the pancreas.

OBJECTIVES: Jaundice impairs cellular immunity, an important defence against the dissemination of cancer. Jaundice is a common mode of presentation in pancreatic head adenocarcinoma. The purpose of this study was to determine whether there is an association between preoperative jaundice and survival in patients who have undergone resection of such tumours. METHODS: Thirty possible survival risk factors were evaluated in a database of over 400 resected patients. Univariate analysis was used to determine odds ratio for death. All factors for which a P-value of <0.30 was obtained were entered into a multivariate analysis using the Cox model with backward selection. RESULTS: Preoperative jaundice, age, positive node status, poor differentiation and lymphatic invasion were significant indicators of poor outcome in multivariate analysis. Absence of jaundice was a highly favourable prognostic factor. Interaction emerged between jaundice and nodal status. The benefit conferred by the absence of jaundice was restricted to patients in whom negative node status was present. Five-year overall survival in this group was 66%. Jaundiced patients who underwent preoperative stenting had a survival advantage. CONCLUSIONS: Preoperative jaundice is a negative risk factor in adenocarcinoma of the pancreas. Additional studies are required to determine the exact mechanism for this effect.

Papillary squamous cell carcinoma of the head and neck: clinicopathologic and molecular features with special reference to human papillomavirus.

A relationship between human papillomavirus (HPV) infection and papillary squamous cell carcinoma (PSCC) has been suggested. However, to date, no studies have thoroughly and directly evaluated for transcriptional activity of the virus or the clinicopathologic significance of HPV-positive PSCC. Forty-eight cases of PSCC were retrieved from our surgical pathology database and were reviewed by 4 study pathologists, with tumors defined as SCC with a significant component of papillary growth in the tumor. Immunohistochemical analysis for p16 and p53 was performed. Overexpression of p16 was used as a surrogate marker of transcriptionally active HPV. Transcriptional activity was also directly evaluated using RNA in situ hybridization to detect high-risk HPV E6/E7 mRNA. Clinical follow-up data were obtained by chart review. Seven cases were located in the oral cavity, 19 in the oropharynx, and 22 in the larynx. Two morphologic types of PSCC were identified: keratinizing type, in which the epithelial cells showed a maturation trend with minimal surface parakeratin, and nonkeratinizing type, in which the papillae were completely covered by immature basaloid cells. Transcriptionally active HPV was present in 23 of 43 (53.4%) tumors. The majority of tumors harboring transcriptionally active HPV arose in the oropharynx, showed nonkeratinizing morphology, were p16 positive, and p53 negative. Transcriptionally active HPV was also present in many laryngeal and oral cavity PSCCs. Overall survival, disease-specific survival, and disease-free survival were favorable and did not significantly differ by anatomic subsite. However, HPV-related tumors showed a trend toward better survival.

Microscopic margins and patterns of treatment failure in resected pancreatic adenocarcinoma.

OBJECTIVE: To correlate microscopic margin status with survival and local control in a large cohort of patients from a high-volume pancreatic cancer center. DESIGN: Retrospective database review. A uniform procedure for margin analysis was used with 4-color inking (neck, portal vein groove, uncinate, and posterior pancreatic margin) by the surgeon in the operating room. SETTING: A tertiary care hospital. PATIENTS: We reviewed patients who underwent pancreaticoduodenectomy between September 1, 1997, and December 31, 2008, from a prospective, institutional database. MAIN OUTCOME MEASURES: Using Cox regression models, we identified pathologic characteristics associated with local recurrence (LR) after controlling for potential confounding variables. Overall and LR-free survival curves were generated by the Kaplan-Meier method. RESULTS: Of 285 patients who underwent pancreaticoduodenectomy for pancreatic adenocarcinoma, 97 (34.0%) had 1 or more positive microscopic margins (uncinate, 16.5%; portal vein groove, 8.8%; neck, 7.7%; and posterior, 10.5%). A total of 198 patients (69.5%) recurred, with the first site of failure being LR only in 47 (23.7%), local plus distant recurrence in 42 (21.2%), and distant recurrence only in 109 (55.1%). Patients with LR only were significantly more likely to have lymph node involvement (adjusted hazard ratio, 2.66; 95% CI, 1.25-5.63) or a positive posterior margin (adjusted hazard ratio, 4.27; 95% CI, 2.07-8.81). Patients with a positive posterior margin had significantly poorer LR-free survival with (P < .001) or without (P = .01) lymph node involvement. CONCLUSIONS: When systematically assessed, the incidence of positive microscopic margins is high. Positive posterior margins and lymph node involvement were each independently and significantly associated with LR.

Extracapsular extension is a poor predictor of disease recurrence in surgically treated oropharyngeal squamous cell carcinoma.

Extracapsular extension in squamous cell carcinoma nodal metastases usually predicts worse outcome. However, there are no standard histologic grading criteria for extracapsular extension, and there have been few studies on oropharyngeal squamous cell carcinoma alone. We studied the extent of extracapsular extension utilizing a novel grading system and correlated grades with outcomes while controlling for p16 status. A cohort of surgically treated oropharyngeal squamous cell carcinoma cases were reviewed and metastases graded as 0 (within substance of node), 1 (filling subcapsular sinus with thickened capsule/pseudocapsule, but no irregular peripheral extension), 2 (≤1 mm beyond capsule), 3 (>1 mm beyond capsule), or 4 (no residual nodal tissue or architecture; 'soft tissue metastasis'). There were 101 cases, for which p16 was positive in 90 (89%). Extracapsular extension grades did not correlate with nodal size (P=0.28) or p16 status (P=0.8). In follow up, 10 patients (10%) had disease recurrence with only 3 of 64 (5%) grade 0-3 cases and 7 of 37 (19%) with grade 4 recurring (P=0.04). Grade 4 extracapsular extension was associated with poorer survival (P<0.01). However, grade 4 extracapsular extension correlated with higher T-stage (P=0.02), and in multivariate analysis, was not significantly associated with poorer overall (P=0.14) disease-free (P=0.2), or disease-specific survival (P=0.09). The impact of extracapsular extension in nodal metastases is limited in oropharyngeal squamous cell carcinoma. Only extracapsular extension grade 4 associates with poorer outcomes, but not independently of T-stage and other variables.

Undifferentiated carcinoma of the oropharynx: a human papillomavirus-associated tumor with a favorable prognosis.

Undifferentiated carcinoma (undifferentiated carcinoma, nasopharyngeal type, or lymphoepithelial carcinoma) is an uncommon and histologically distinct tumor in the oropharynx, which in Western countries, has been clearly shown not to harbor Epstein Barr virus (EBV). We sought to analyze these tumors for human papillomavirus (HPV) and to examine their clinical outcomes. All cases of oropharyngeal carcinoma diagnosed as 'undifferentiated' or 'lymphoepithelial' were retrieved from the department files at Barnes-Jewish Hospital. After consensus review by all three study pathologists, 16 were found to have diagnostic histological features and to lack distinguishing characteristics of other oropharyngeal cancers. Immunohistochemistry for p16 and p53 and in-situ hybridization for HPV and EBV encoded small RNA were performed. p16-positive but HPV in situ hybridization-negative cases were analyzed by polymerase chain reaction for high-risk HPV types. The results were correlated with pathological findings and clinical follow up. There were 16 patients. The average age was 59.2 years, 14 patients (88%) were smokers, and 13 (81%) had nodal metastases. In all, 14 cases (88%) were p16 positive and 15 (94%) were HPV positive by in situ hybridization and/or polymerase chain reaction. All cases were negative for EBV, and p53 was overexpressed in five (33%), four of which were HPV positive. Disease recurred in only three patients and two of these died with disease at 38 and 136 months, respectively. Three year overall, disease-free, and disease-specific survival rates were 54, 78, and 100%, respectively. In summary, in our patient population, the majority of oropharyngeal undifferentiated carcinomas harbor transcriptionally active HPV but not EBV. Almost all overexpress p16, and few have p53 overexpression. Disease-specific survival is comparable to published rates for other HPV-related oropharyngeal squamous cell carcinoma variants and is better than that of HPV-negative carcinomas.