Patterns and Utility of Calprotectin in Patients with Microscopic Colitis

Context

Calprotectin is a cytoplasmic-protein that is released upon neutrophilic activation. Measuring fecal-calprotectin (FC) is used for monitoring inflammatory bowel disease activity and distinguishing it from irritable bowel syndrome. However, its utility in other types of colitis has not been well-investigated.

Design

Cases of collagenous-colitis (CC) and lymphocytic-colitis (LC) between 2015 and 2020 were retrieved from our institution surgical pathology database. Endoscopy and histopathologic examination findings were reviewed to confirm the diagnosis. 15 CC and 13 LC cases were included as FC was done at the time of initial diagnosis (before therapy). 62 cases of normal endoscopy and histopathologic examination were selected as a control group. One-way analysis of the variance (ANOVA) and receiver operating curve (ROC) analysis of FC were performed.

Results

Abnormally elevated FC (> 50 ug/g) was identified in 77% and 64% of CC and LC cases, respectively. Only 1.6% of control cases had mildly elevated FC of 54 ug/g. The mean FC of CC and LC groups (246 and 214, respectively) were significantly higher than the control group (22.4); p= <0.05. LC and CC groups had no statistically significant difference in the mean FC (p = 0.8). The area under the curve was 0.93 with ROC analysis. At the suggested cut-off of 50 ug/g, the sensitivity was 78.6%, specificity was 98.4% with a likelihood ratio of 48.7.

Conclusions

Fecal calprotectin can be elevated in patients with lymphocytic or collagenous colitis, however with no statistically significant difference between the two types. Therefore, it has the potential to be used as a marker for screening, diagnosis, and monitoring response to therapy in patients with microscopic colitis.

Intratumoral talimogene laherparepvec injection with concurrent preoperative radiation in patients with locally advanced soft-tissue sarcoma of the trunk and extremities: phase IB/II trial

Background

Soft-tissue sarcomas (STS) in the extremities and trunk treated with standard-of-care preoperative external beam radiation therapy (EBRT) followed by surgical resection are associated with local and distant relapses. In preclinical studies, oncolytic virotherapy in sarcoma has demonstrated antitumor effects via direct intratumoral oncolysis and cytotoxic T-cell–mediated immune responses. Talimogene laherparepvec (TVEC) is a replication-competent, immune-enhanced, oncolytic herpes simplex virus type 1 engineered for intratumoral injection; it has been approved by the FDA for the treatment of locally advanced and metastatic melanoma.

Methods

We explored a novel combination of TVEC with standard-of-care EBRT administered preoperatively in patients with locally advanced STS of the extremities and trunk in a phase IB/II clinical trial. Thirty patients with primary STS >5 cm for which EBRT was indicated to achieve negative margins were enrolled. FDA-approved TVEC doses were used. Immune correlative studies in peripheral blood, biopsy and resected tumor tissues were performed.

Results

No dose-limiting toxicity was observed. Adverse events were similar to those reported in prior studies with TVEC. One patient with myxoid liposarcoma exhibited a partial response. Seven of the 29 (24%) evaluable patients achieved 95% pathological necrosis. None of the patients developed a herpes infection due to the treatment. Eight of the 29 (27%) patients developed postoperative wound complications, which is consistent with previous studies. None of the patients developed local recurrence after surgical resection of the primary sarcoma. 2-year progression-free and overall survival were 57% and 88%, respectively. Caspase-3 demonstrated increased expression of both in TVEC-treated tissue samples as compared with control samples treated with radiation alone.

Conclusion

Preoperative intratumoral TVEC with concurrent EBRT for locally advanced STS is safe and well-tolerated. This combination treatment may enhance immune responses in some cases but did not increase the proposed rate of pathological necrosis. The Caspase-3 biomarker may be associated with a positive effect of TVEC in sarcoma tumor tissue and should be explored in future studies.

Trial registration number

NCT02453191.

Mucinous Cystic Neoplasm of the Cystic Duct: A Rare Location of a Rare Entity

Mucinous cystic neoplasms (MCNs) are uncommon cystic lesions that arise in the liver and biliary system (MCN-LBS) and the pancreas (MCN-P) and rarely arise from the extrahepatic biliary system. Histologically, these lesions are defined by the presence of variably mucin-producing epithelium with ovarian-like, hypercellular mesenchymal stroma. Herein, we present a case of extrahepatic MCN-LBS in a 51-year-old woman. This lesion arose from the cystic duct and was removed via laparoscopic cholecystectomy. Histologic examination confirmed the diagnosis. To our knowledge, this is the third case report of an MCN-LBS arising from the cystic duct in the English literature. In this article, we review clinical and histologic characteristics of MCNs and present two other reports of MCN-LBS of the cystic duct.

Case of a Large Pedunculated Biliary Cholesterol Polyp With Osseous Metaplasia

Cholesterol polyps are the most common benign gallbladder polyps and are usually seen in a background of cholesterolosis. Rarely, they can harbor foci of osseous metaplasia, which is an event of uncertain clinical significance that might be confused with cholelithiasis clinically or radiologically. Herein we report the case of a 78-year-old female with a 1.8-cm pedunculated polyp arising in the gallbladder body. Histologic examination showed microscopic foci of osseous metaplasia, characterized by heterotropic bone trabeculae rimmed by osteoblasts and surrounded by osteoclast giant cells. To the best of our knowledge, this case is the third case report of a cholesterol polyp with osseous metaplasia in the English literature. We also review the relative pathogenesis, clinical and pathologic findings, and previous reports.

Iron alters macrophage polarization status and leads to steatohepatitis and fibrogenesis

We have previously demonstrated that iron overload in hepatic reticuloendothelial system cells (RES) is associated with severe nonalcoholic steatohepatitis (NASH) and advanced fibrosis in patients with nonalcoholic fatty liver disease (NAFLD). Recruited myeloid-derived macrophages have gained a pivotal position as drivers of NASH progression and fibrosis. In this study, we used bone marrow-derived macrophages (BMDM) from C57Bl6 mice as surrogates for recruited macrophages and examined the effect of iron on macrophage polarization. Treatment with iron (ferric ammonium citrate, FAC) led to increased expression levels of M1 markers: CCL2, CD14, iNOS, IL-1β, IL-6, and TNF-α; it also increased protein levels of CD68, TNF-α, IL-1β, and IL-6 by flow cytometry. This effect could be reversed by desferrioxamine, an iron chelator. Furthermore, iron loading of macrophages in the presence of IL-4 led to the down-regulation of M2 markers: arginase-1, Mgl-1, and M2-specific transcriptional regulator, KLF4. Iron loading of macrophages with IL-4 also resulted in reduced phosphorylation of STAT6, another transcriptional regulator of M2 activation. Dietary iron overload of C57Bl6 mice led to hepatic macrophage M1 activation. Iron overload also stimulated hepatic fibrogenesis. Histologic analysis revealed that iron overload resulted in steatohepatitis. Furthermore, NAFLD patients with hepatic RES iron deposition had increased hepatic gene expression levels of M1 markers, IL-6, IL-1β, and CD40 and reduced gene expression of an M2 marker, TGM2, relative to patients with hepatocellular iron deposition pattern. We conclude that iron disrupts the balance between M1/M2 macrophage polarization and leads to macrophage-driven inflammation and fibrogenesis in NAFLD.

Searching for Bacterial Biofilm in Recurrent Cholangitis in Primary Sclerosing Cholangitis: A Case Presentation and Introduction of an Unexplored Disease Mechanism

Inflammation and fibrosis of the bile ducts are the defining pathological characteristics of primary sclerosing cholangitis (PSC). A previously unexplored mechanism for recurrent cholangitis, one of PSC's most common presentations, is bacterial colonization of the biliary epithelium in the form of biofilm, which may confer resistance to antibiotics and host phagocytic machinery. The aim of the current study was to assess whether bacteria could be seen on the liver explant and whether they organized in the form of biofilm. An explanted PSC liver from a 60-year-old male who suffered from recurrent cholangitis was formalin-fixed, paraffin-embedded and Gram stained. The specimens were observed under light microscopy. Neither bacteria nor biofilm were detected. We did not detect bacteria or biofilm in the liver explant of a single PSC patient with recurrent cholangitis using standard light microscopy. We suspect this may be in part due to techniques related to tissue preservation and microscopy.

Genomic variants link to hepatitis C racial disparities

Chronic liver diseases are one of the major public health issues in United States, and there are substantial racial disparities in liver cancer-related mortality. We previously identified racially distinct alterations in the expression of transcripts and proteins of hepatitis C (HCV)-induced hepatocellular carcinoma (HCC) between Caucasian (CA) and African American (AA) subgroups. Here, we performed a comparative genome-wide analysis of normal vs. HCV+ (cirrhotic state), and normal adjacent tissues (HCCN) vs. HCV+HCC (tumor state) of CA at the gene and alternative splicing levels using Affymetrix Human Transcriptome Array (HTA2.0). Many genes and splice variants were abnormally expressed in HCV+ more than in HCV+HCC state compared with normal tissues. Known biological pathways related to cell cycle regulations were altered in HCV+HCC, whereas acute phase reactants were deregulated in HCV+ state. We confirmed by quantitative RT-PCR that SAA1, PCNA-AS1, DAB2, and IFI30 are differentially deregulated, especially in AA compared with CA samples. Likewise, IHC staining analysis revealed altered expression patterns of SAA1 and HNF4α isoforms in HCV+ liver samples of AA compared with CA. These results demonstrate that several splice variants are primarily deregulated in normal vs. HCV+ stage, which is certainly in line with the recent observations showing that the pre-mRNA splicing machinery may be profoundly remodeled during disease progression, and may, therefore, play a major role in HCV racial disparity. The confirmation that certain genes are deregulated in AA compared to CA tissues also suggests that there is a biological basis for the observed racial disparities.