Carcinoma Of Small Intestine Research Articles

Medullary carcinomas of the nonampullary small intestine: association with coeliac disease, mismatch repair deficiency, PD-L1 expression, and favourable prognosis.

Gastrointestinal medullary carcinoma is a rare histologic subtype of adenocarcinoma. As nonampullary small bowel medullary carcinomas (SB-MCs) are poorly characterized, we aimed to analyse their clinicopathologic and immunohistochemical features and to compare them with nonmedullary small bowel adenocarcinomas (NM-SBAs). Surgically resected SBAs collected through the Small Bowel Cancer Italian Consortium were classified as SB-MCs (carcinomas with ≥50% of tumour fulfilling the typical histologic criteria of MC) or NM-SBAs. Immunohistochemistry for cytokeratin (CK)7, CK20, CDX2, programmed death-ligand 1 (PD-L1) and mismatch repair proteins was performed in both SB-MCs and NM-SBAs. SB-MCs were also tested for CK8/18, synaptophysin, SMARCB1, SMARCA2, SMARCA4, and ARID1A and for Epstein-Barr virus (EBV)-encoded RNAs by in-situ hybridization. MLH1 promoter methylation status was evaluated in MLH1-deficient cases. Eleven SB-MCs and 149 NM-SBAs were identified. One (9%) SB-MC was EBV-positive, while 10 (91%) harboured mismatch repair deficiency (dMMR). MLH1 promoter hypermethylation was found in all eight dMMR SB-MCs tested. Switch/sucrose nonfermentable deficiency was seen in two (18%) SB-MCs, both with isolated loss of ARID1A. Compared with NM-SBAs, SB-MCs exhibited an association with coeliac disease (P < 0.001), higher rates of dMMR (P < 0.001), and PD-L1 positivity by both tumour proportion score and combined positive score (P < 0.001 for both), and a lower rate of CK20 expression (P = 0.024). Survival analysis revealed a better prognosis of SB-MC patients compared to NM-SBA cases (P = 0.02). SB-MCs represent a distinct histologic subtype, with peculiar features compared to NM-SBAs, including association with coeliac disease, dMMR, PD-L1 expression, and better prognosis.

Abstract B011: Lower incidence of small intestinal adenocarcinomas may be due to constrained copy number karyotype and increased immune surveillance

Abstract Aim: To evaluate the genomic profiles of duodenal adenocarcinomas and explore the role of the immune system in the evolution of these cancers. Introduction: Tumours of the small intestine are rare and represent the smallest fraction of all gastrointestinal (GI) cancers despite being the largest organ in the GI tract. As a result, they have not been well characterised at the molecular level, and consequently are often clinically managed similarly to colorectal cancers. Methods: Here we performed shallow whole-genome sequencing (sWGS) on 125 cases of the most common adenocarcinomas in the small intestine, duodenal adenocarcinomas, and compared their somatic copy number aberrations to 880 upper and lower GI primary adenocarcinomas from the TCGA. Furthermore, we reanalysed published whole exome sequencing (WEX) from a further 91 small intestinal carcinomas to assess the immune landscape. Results: In our sWGS cohort, we found that duodenal adenocarcinomas have a significantly lower incidence of genome doubling (20%) than elsewhere in the GI tract (colon=43.6%, stomach=44%, rectum=55%, oesophagus=64.3%). Percentage of genome altered (PGA) is affected by the amount of genome doubling present, by median centering the proportion of the genome altered we could circumvent this. Duodenal cancers also had a significantly lower median centered percentage genome aberrated (mPGA) than colon (p=6.3 × 10-4, es=0.176), rectal (p=3 × 10-5, es=0.279), stomach (p=1.5 × 10-8, es=0.309) and oesophageal (p=1.2 × 10-11, es=0.546) adenocarcinomas. Inter-tumour heterogeneity of copy number alterations was lowest in duodenal cancers compared to other GI cancer types (p&amp;lt;2.22 × 10-16 for all and effect size &amp;gt; 0.7 for all). Within the previously published WEX cohort of small intestinal adenocarcinomas, we observed a higher proportion of clonal mutations that are neoantigens (vs not-neoantigens) in immune escaped tumours than non-escaped tumours (p=0.016) and found that small intestinal tumours are more likely to be immune escaped than colon cancers. Escaped small intestinal tumours were associated with a significantly decreased overall survival compared to non-escaped tumours (HR 2.197 (95% CI, 1.736– 46.63); p=0.009). Further, dNdS analysis indicated strong immune-mediated negative selection on clonal non-synonymous mutations in the immunopeptidome in most tumours. Conclusions: The decreased inter-tumour heterogeneity of karyotypes amongst small intestinal cancers compared to other GI cancers could indicate more restricted routes for karyotype evolution in the small intestine. Our data also suggest a more pertinent role for immune-predation than elsewhere in the GI tract. Together this may explain their lower incidence. Citation Format: Salpie Nowinski, Vickna Balarajah, Ann-Marie Baker, Riku Katainen, Christine Hughes, Qingli Guo, Luis Zapata, Eszter Lakatos, Hemant M. Kocher, Trevor A. Graham. Lower incidence of small intestinal adenocarcinomas may be due to constrained copy number karyotype and increased immune surveillance [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Translating Cancer Evolution and Data Science: The Next Frontier; 2023 Dec 3-6; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_2):Abstract nr B011.

A comprehensive analysis of clinical characterization in 149 Chinese patients with Lynch syndrome.

10606 Background: Lynch syndrome (LS) caused by germline pathogenic variants (PVs) in mismatch repair (MMR) genes, which increased risk of malignancy in different organs. LS-related tumors included colorectal, endometrial, gastric, ovarian, pancreas, urinary system, biliary tract, central nervous system, skin and small intestinal carcinomas (CRC, EC, GC, OC, PC, UST, BTC, CNST, SC, SIC). As sequencing technology becomes more economical and widespread, more MMR PVs were detected in LS-unrelated tumors. The aim of this study was to explore the clinical characterization in Chinese real-world LS solid tumor. Methods: We applied next-generation sequencing (NGS) screening to detect the germline mutation in MMR (include MLH1, MSH2, MSH6, PMS2), tumor mutation burden (TMB) and microsatellite instability (MSI) in Chinese solid tumor patients (pts). In the cohort, lung cancer (LC) was the most common cancer type, followed by CNST, CRC, hepatic carcinoma (HC). Results: 149 LS pts were observed in our cohort, among which 81.2% (121/149) carried LS-related tumors (44 CRC, 47 CNST, 9 EC, 9 BTC, 4 UST, 3 OC, 2 GC, 2 SC, 1 SIC), 18.8% (28/149) carried with LS-unrelated tumors(18 LC, 5 HC, 3 sarcoma, 1 ampullary carcinoma, 1 peritoneal cancer), and the age showed no significant difference between LS-related tumors and LS-unrelated tumors (average age: 48 vs 53, p=0.08). The distribution of MMR PVs were as follows: MLH1 (37, 24.8%), MSH2 (46, 30.9%), MSH6 (34, 22.8%), PMS2 (32, 21.5% ), and comparative analysis showed that LS-related tumors tended to carry MLH1 and MSH2 PVs (60.3%, 73/121), while LS-unrelated tumors tended to carry MSH6 and PMS2 PVs (67.9%, 19/28) ( p&lt;0.05). 46.3% LS pts had MSI-H, concentrated in MLH1 or MSH2 PVs carriers. MSI-H showed a higher detection rate in LS-related tumors other than LS-unrelated tumors(56.1% vs 3.6%, p&lt;0.005). Among LS-related tumors, the top 3 prevalence of MSI-H were CRC (93.2%, 41/44), BTC (55.6%, 5/9) and EC (44.4%, 4/9), which were lower in CNST (31.9%, 15/47). In addition, we found that the rate of TMB-H in LS-related tumors was also higher than LS-unrelated tumors ( p&lt;0.001). Conclusions: In our dates, 18.8%(28/149) LS pts carried with LS-unrelated tumors, which emphasized the importance of germline genetic assessment for LS in pan-cancer. In addition, MSI-H, TMB-H and MMR PVs distributions were significantly different in LS-related tumors and LS-unrelated tumors. The differences about LS clinical characterization associated with MMR genes require further study.

Abstract 869: Molecular genetic positioning of small intestine and papilla of Vater carcinomas including clinicopathological classification

Abstract Purpose: Small intestine carcinoma (SIC) cases in Japan have recently been treated with chemotherapy according to colorectal carcinoma classification, while papilla of Vater carcinoma (PVC) cases according to cholangiocarcinoma (CHC) classification. However, few research reports support the molecular genetic validity of these therapeutic choices. Here, we investigated the clinicopathological and molecular genetic factors of SIC and PVC. Patients and Methods: We used the data from the Japanese version of The Cancer Genome Atlas (JCGA). Additionally, molecular genetic data on gastric adenocarcinoma (GAD), colorectal adenocarcinoma (CRAD), pancreatic ductal adenocarcinoma (PDAC), and CHC were also referred to. Results: This study consisted of tumor specimens from 12 cases of SIC and three cases of PVC treated from January 2014 to March 2019. Among them, six cases had pancreatic invasion. t-Distributed Stochastic Neighbor Embedding analysis showed that the gene expression pattern of SIC was similar not only to those of GAD and CRAD, but also to that of PDAC in the pancreatic invasion cases. In addition, PVC resembled the GAD, CRAD, and PDAC, rather than the CHC. The molecular genetic characteristics of the six patients with pancreatic invasion were: one had high microsatellite instability (MSI-High), two had a TP53 driver mutation, and three had tumor mutation burden values &amp;lt; 1 mutation/Mb with no driver mutation. Conclusions: The molecular genetics of SIC and PVC suggested that they may be similar to GAD, CRAD, and PDAC. In addition, the data demonstrate that pancreatic invasive cases may be classified into several subtypes using molecular genetic factors. Citation Format: Yukiyasu Okamura, Masanori Nakamura. Molecular genetic positioning of small intestine and papilla of Vater carcinomas including clinicopathological classification [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 869.

Molecular genetic positioning of small intestine and papilla of Vater carcinomas including clinicopathological classification.

Small intestine carcinoma (SIC) cases in Japan have recently been treated with chemotherapy according to colorectal carcinoma classification, while papilla of Vater carcinoma (PVC) cases according to cholangiocarcinoma (CHC) classification. However, few research reports support the molecular genetic validity of these therapeutic choices. Here, we investigated the clinicopathological and molecular genetic factors of SIC and PVC. We used the data from the Japanese version of The Cancer Genome Atlas. Additionally, molecular genetic data on gastric adenocarcinoma (GAD), colorectal adenocarcinoma (CRAD), pancreatic ductal adenocarcinoma (PDAC), and CHC were also referred to. This study consisted of tumor samples from 12 patients of SIC and three patients of PVC treated from January 2014 to March 2019. Among them, six patients had pancreatic invasion. t-Distributed stochastic neighbor embedding analysis showed that the gene expression pattern of SIC was similar not only to those of GAD and CRAD, but also to that of PDAC in the pancreatic invasion patients. In addition, PVC resembled the GAD, CRAD, and PDAC, rather than the CHC. The molecular genetic characteristics of the six patients with pancreatic invasion were: one had high microsatellite instability, two had a TP53 driver mutation, and three had tumor mutation burden values <1 mutation/Mb with no driver mutation. In this study, the extensive gene expression profiling of organ carcinomas newly suggests that SIC or PVC may resemble GAD, CRAD, and PDAC. In addition, the data demonstrate that pancreatic invasive patients may be classified into several subtypes using molecular genetic factors.

Tumor Microenvironment Prognostic Risk and Its Association With MUC5AC in Ampullary Carcinoma.

The tumor-host interaction in the tumor microenvironment (TME) affects the prognosis of patients with malignant tumors. TME assessed via tumor budding (BD) and tumor-infiltrating lymphocyte (TIL) had a prognostic impact in patients with nonampullary small intestinal and colorectal carcinomas. In ampullary carcinoma (AC), MUC5AC was recently revealed as a significant prognosticator, but studies about the TME have not been conducted. To assess TME-based prognostic risk in AC. We generated a collective TME risk index based on high-grade BD at the invasive front (BD3) and high density of stromal-TIL (>5%) in 64 surgically resected ACs. We evaluated its predictive values for overall survival (OS) and recurrence-free survival (RFS). We also investigated the relationship of TME to MUC5AC expression. TME prognostic risk index was classified into low-risk (BDLow/TILHigh; 26 of 64; 41%), intermediate-risk (BDLow/TILLow or BDHigh/TILHigh; 23; 36%), and high-risk (BDHigh/TILLow; 15; 23%) groups. Higher TME prognostic risk was associated with higher tumor grade (P = .03), lymphovascular invasion (P = .05), and MUC5AC immunopositivity (P = .02). TME prognostic risk index displayed better predictive ability for both OS (53.9 versus 46.1 versus 42.2) and RFS (24.8 versus 16.9 versus 15.3) than BD or TIL alone. In multivariate analysis, TME prognostic risk index was an independent prognosticator for OS (P = .003) and RFS (P = .03). TME risk index in combination with BD and TIL was a stronger predictor of prognostic risk stratification than either BD or TIL alone for both OS and RFS in patients with AC. MUC5AC may modulate the interaction between tumor cells and immunity toward enhancing invasiveness in TME.

Disulfated Ophiuroid Type Steroids from the Far Eastern Starfish Pteraster marsippus and Their Cytotoxic Activity on the Models of 2D and 3D Cultures.

New steroidal 3β,21-disulfates (2–4), steroidal 3β,22-disulfate (5), and the previously known related steroidal 3β,21-disulfate (1) were isolated from the ethanolic extract of the Far Eastern starfish Pteraster marsippus, collected off Urup Island in the Sea of Okhotsk. The structures of these compounds were determined by intensive NMR and HRESIMS techniques as well as by chemical transformations. Steroids 2 and 3 have an oxo-group in the tetracyclic nucleus at position C-7 and differ from each other by the presence of the 5(6)-double bond. The Δ24-22-sulfoxycholestane side chain of the steroid 5 has not been found previously in the starfish or ophiuroid steroids. The cytotoxic activities of 1, 4, 5, and the mixture of 2 and 3 were determined on the models of 2D and 3D cultures of human epithelial kidney cells (HEK293), melanoma cells (SK-MEL-28), small intestine carcinoma cells (HuTu80), and breast carcinoma cells (ZR-75-1). The mixture of 2 and 3 revealed a significant inhibitory effect on the cell viability of human breast carcinoma ZR-75-1 cells, but other tested compounds were less effective.

A first-in-human phase Ia/b, open-label, multicenter study of the TRAILR2 agonist BI 905711 in patients (pts) with advanced gastrointestinal (GI) cancers.

TPS222 Background: Activation of the tumor necrosis factor-related apoptosis-inducing ligand receptor 2 (TRAILR2) induces apoptosis via caspase activation. Targeting TRAILR2 is an attractive therapeutic strategy, but some early TRAILR2 agonists were associated with severe hepatotoxicity. Cadherin 17 (CDH17), a membrane protein highly expressed in GI cancers, is not expressed in normal hepatocytes so using CDH17 as a liver-sparing anchor may avoid hepatotoxicity. BI 905711 is a tetravalent bispecific antibody that cross-links TRAILR2 with CDH17 to induce CDH17-dependent TRAILR2 oligomerisation. In preclinical assays, BI 905711 demonstrated a potency shift of ̃1000 fold versus the 1st-generation TRAILR2 agonist lexatumumab. BI 905711 induced apoptosis in CDH17-positive tumor cells in vitro, impaired tumor growth in pt-derived colorectal cancer (CRC) xenografts, and no hepatotoxicity was observed. Methods: This phase Ia/Ib study (NCT04137289) aims to determine the safety, maximum tolerated dose (MTD), pharmacokinetics (PK), pharmacodynamics, and preliminary efficacy of BI 905711 in pts with advanced, refractory GI cancers. Up to 140 adult pts with histologically confirmed, advanced unresectable/metastatic colorectal, gastric, esophageal or pancreatic adenocarcinoma, cholangiocarcinoma, or gallbladder or small intestine carcinoma, who have progressed on standard-of-care therapies, will be enrolled. In phase Ia, pts will receive intravenous BI 905711 at escalating doses (range 0.02–4.8 mg/kg) every 14 days, until disease progression or unacceptable toxicities. Dose escalation will be guided by a Bayesian logistic regression model with overdose control based on dose-limiting toxicities (DLTs) in the first 28 days. In phase Ia, a minimum number of CRC pts will be enrolled to each cohort: ≥1 CRC pt at each of the 2 lowest dose levels (0.02/0.06 mg/kg) and 4 pts at each subsequent dose level (0.2/0.6/1.2/2.4/3.6/4.8 mg/kg). In parallel to dose escalation in CRC pts, up to 4 pts with non-CRC GI cancers will be included at the dose level below that of the CRC cohort. If an objective response (OR) per RECIST v1.1 is observed in CRC or non-CRC GI pts at a safe dose level, up to 10 additional pts with the same tumor type will be recruited at that dose level. In phase Ib, CRC pts will be randomized into up to 4 dose cohorts (as determined in phase Ia; n=20 each) to define the recommended phase II dose. The primary endpoints are determination of the MTD based on the proportion of pts with DLTs (phase Ia) and OR rate based on RECIST v1.1 (phase Ib). Secondary endpoints include PK parameters and OR in pts with measurable disease (phase Ia), and disease control, tumor shrinkage, duration of response, and progression-free survival (phase Ib). Trial enrollment is ongoing, with 33 pts enrolled to date. Clinical trial information: NCT04137289.

Medullary carcinoma of jejunum presenting as perforation peritonitis: A case report

Small intestinal medullary carcinoma (MC) is a newly recognized subclass of small intestinal carcinomas and is an exceptional entity for this site. A search of the literature for similar cases arising in the small intestine revealed only six previously reported cases. Here we present a case of MC arising in the jejunum of a 65-year-old male. The patient presented to the emergency with features of perforation peritonitis with liver metastasis and no known predisposing factors like inflammatory bowel disease and celiac disease. Studies conducted on this tumor's colonic counterpart have shown microsatellite instability (MSI) and B-type Raf kinase (BRAF) mutations; however, few exceptions are known. Also, this subtype of carcinoma is known to have a better prognosis than its other histological subtypes.

Abstract 1637: ATP-citrate lyase transgenic mice frequently develop lymphoma/leukemia spontaneously

Abstract ATP-citrate lyase (ACLY) catalyzes the generation of acetyl-CoA from citrate. ACLY expression is upregulated and/or ACLY is phosphorylated in several types of cancer. We generated ACLY transgenic mice (Tg) to examine the role of ACLY in carcinogenesis. (Materials and methods) Using human ACLY cDNA under the ROSA26 promoter, Tg with a C57BL background was established. We observed the Tg without treatment. Statistical analyses were performed using the Chi-square and Fisher's exact test. (Results) Of 24 male (M) Tg, aged 24–30 months, 14 (58%), 7 (29%), and 1 (4%) spontaneously developed lymphoma/leukemia (LL), lung carcinoma (LC), and small intestinal carcinoma (SIC), respectively. Since some C57BL mouse colonies are genetically susceptible to LL, and we have previously examined human cases of carcinoma, the Tg were back-crossed with C3H mice, which are resistant to LL and susceptible to carcinoma, especially hepatocellular carcinoma (HCC). A total of 129 (M: 67, female (F): 62) Tg were observed for 18 months. Forty-nine C3H mice (M: 19, F: 30) from the same colony were used as controls. Multiple tumors were counted individually. Seventy-three Tg (57%; M: 41, 61%; F: 32, 52%) and 8 controls (16%; M: 4, 21%; F: 4, 13%) developed cancer. The Tg developed significantly more tumors (total (T), M, F: all p&amp;lt;0.05), including 33 HCC (26%; M: 22, 33%; F: 11, 18%), 28 LL (22%; M: 12, 18%; F: 16, 26%), 7 LC (5%; M: 6, 9%; F: 1, 2%), 4 sarcomas (Sa)(3%; M: 2, 3%; F: 2, 3%), 2 SIC (2%; M: 2, 3%; F: 0), 2 skin appendage carcinomas (SAC) (2%; M: 0; F: 2, 3%), and 1 ovarian cancer (Ov) (1%; F: 1, 2%), than the control mice, which developed 7 HCC (14%; M: 4, 21%; F: 3, 10%), 1 LC (2%; M: 1, 5%; F: 0), and 1 Ov (2%; F: 1, 3%). No LL was seen in the controls. The frequency of HCC did not differ significantly between the Tg and controls (T, M, F: all p&amp;gt;0.05). (Discussion) ACLY was reported to be related to the carcinogenesis of anaplastic large cell lymphoma (Basappa J. et al. Blood 2015 126:465). This study suggests that ACLY might contribute to LL development. Table:Summary of developed cancersNumberTotal cancerHCCLLLCSICSaSACOvACLY12973(57%)*33(26%)28(22%)7(5%)2(2%)4(3%)2(2%)1(1%)Male6741(61%)**22(33%)12(18%)6(9%)2(3%)2(3%)0-Female6232(52%)***11(18%)16(26%)1(2%)02(3%)2(3%)1(2%)Control498(16%)*7(14%)01(2%)0001(2%)Male194(21%)**4(21%)01(5%)000-Female304(13%)***3(10%)000001(3%)*, **, ***; p&amp;lt;0.05 Citation Format: Hiroaki Kanda, Kimie Nomura, Toshihiko Iizuka, Mutsunori Fujiwara, Yuichi Ishikawa, Toshiro Migita. ATP-citrate lyase transgenic mice frequently develop lymphoma/leukemia spontaneously [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1637.

HER2/neu Expression in Gastrointestinal Carcinoma Among South Indians

Background: HER2/neu oncogene overexpression and amplification in breast cancer is well known. Studies have proved its role in gastric cancer and its correlation with the prognosis. Very few studies are there in literature regarding HER2/neu expression in entire gastrointestinal carcinoma. Our study was aimed at HER2/neu expression in gastrointestinal tumors in South Indian Population. M ethods: We included all patients with gastrointestinal carcinoma who either underwent biopsy or surgical excision over the past five years. Slides were reviewed for confirmation of the diagnosis and immunohistochemistry was done using SP3 monoclonal anti-HER2 antibodies. Three independent observers did the scoring for HER2 positivity. Results: Among 35 cases of gastric cancer, only 2 (5.7%) females showed positivity for HER2 scoring and one (2.9%) female showed an equivocal result. All positive and equivocal cases in gastric cancer were intestinal type. Both the cases with HER2 positivity were poorly differentiated tumors. The one with equivocal was a moderately differentiated carcinoma. In colorectal cancer out of 19 cases, only one (5.3%) showed positivity for HER2 whereas in one there was an equivocal response. All the seven cases of small intestinal carcinoma showed negative results for HER2 expression. Conclusion: Overall, HER2/neu expression in gastrointestinal cancer was 4.9%. Female gender, intestinal- type and poorly differentiated cancer showed positivity in gastric cancer. Female gender, left side and low-grade tumor showed positivity in colorectal cancer. Further studies are required with a large sample size to correlate HER2 expression with clinicopathological parameters and its role in prognosis in gastrointestinal carcinomas in the Indian population.

DOP51 Investigation on the role of Par4-associated cell polarity and associated barrier defects in inflammatory bowel diseases

Abstract Background In inflammatory bowel diseases (IBD), epithelial barrier defects occur as a consequence of chronic inflammation. Recent research suggested that cell polarity alterations may be upstream of barrier defects and additionally play a role in IBD-associated carcinogenesis (colitis-associated and small intestinal carcinoma). Par4 is a gene encoding a protein crucial in the development of cell polarity. LKB1, its human homologue, is mutated in Peutz–Jeghers syndrome (PJS), a genetic condition characterised by a higher risk of epithelial cancers. While the pivotal role of Par4/LKB1 in the development of epithelial cell polarity is established, its involvement in IBD-associated barrier defects and carcinogenesis is yet to be defined. Methods Endoscopic bowel mucosa samples from patients with Crohn’s disease, ulcerative colitis, PJS and controls were analysed to assess expression and localisation of Par4/LKB1. Cryosections were immunostained for Par4/LKB-1 along with a diverse set of markers of cell polarity and intercellular adhesion. The analysis was performed by confocal laser scanning microscopy in order to compare the expression of mucosal as well as the subcellular localisation of Par4/LKB1 in the gut mucosa. A quantitative analysis of protein expression with western blotting was performed as well. The function of Par4/LKB1 in intestinal epithelial cells (IEC) was evaluated by means of a Par4-deficient IEC model as well as in an IEC Par4-overexpression model. Moreover, a preliminary assessment of the possible role of Par4/LKB1-related polarity processes in IBD-associated carcinomas was performed through scanning genetic data from colitis-associated carcinomas for potential Par4-related mutations and altered Par4/LKB1 expression. Results The immunofluorescent staining allowed visualisation of intracellular expression of Par4 in epithelia from PJS, IBD patients and controls. In PJS-polyps, despite the alteration of regular tissue architecture typical of these lesions, the polarity of epithelial cells was maintained - contrary to control tissue, a punctate pattern of the Par4 staining was shown. In IBD tissue, no relevant differences in Par4 expression at confocal microscopy, as well as a quantitative assessment, were observed as compared with controls. No differences were observed in PJS or IBD samples as regards the expression of cell polarity markers such as Par3, CD71, crb3 or adhesion molecules such as ZO-1, e-cadherin, occludin, JAM-A. As regards the IEC model, we observed that Caco-2/BBe cells overexpressing Par4/LKB1 showed enhanced Par4/LKB1 cytosolic staining at immunofluorescence. In this model, a defective epithelial polarity and organisation on permeable supports could be observed in Caco2/BBe cysts in parallel with reduced expression of native LKB1 as seen in western blots. Preliminary analysis of data from our colitis-associated carcinomas database suggested various pathways potentially involving Par4/LKB1, yet no direct analysis of tissue samples for Par4-related mutations was performed yet. Conclusions Altered expression of Par4 in epithelial cells may influence the development of a functional epithelial barrier as suggested by IEC models. Par4/LKB1 as a known oncosuppressor gene is involved in a number of pathways potentially relevant for carcinogenesis in IBD; however, a direct connection between Par4-related alteration of the epithelial barrier and carcinogenesis is yet to be established.

A side-by-side evaluation of [18F]FDOPA enantiomers for non-invasive detection of neuroendocrine tumors by positron emission tomography

Neuroendocrine tumors (NETs) are an extremely heterogenous group of malignancies with variable clinical behavior. Molecular imaging of patients with NETs allows for effective patient stratification and treatment guidance and is crucial in selection of targeted therapies. Positron emission tomography (PET) with the radiotracer L-[18F]FDOPA is progressively being utilized for non-invasive in vivo visualization of NETs and pancreatic β-cell hyperplasia. While L-[18F]FDOPA-PET is a valuable tool for disease detection and management, it also exhibits significant diagnostic limitations owing to its inherent physiological uptake in off-target tissues. We hypothesized that the D-amino acid structural isomer of that clinical tracer, D-[18F]FDOPA, may exhibit superior clearance capabilities owing to a reduced in vivo enzymatic recognition and enzyme-mediated metabolism. Here, we report a side-by-side evaluation of D-[18F]FDOPA with its counterpart clinical tracer, L-[18F]FDOPA, for the non-invasive in vivo detection of NETs. In vitro evaluation in five NET cell lines, including invasive small intestinal neuroendocrine carcinomas (STC-1), insulinomas (TGP52 and TGP61), colorectal adenocarcinomas (COLO-320) and pheochromocytomas (PC12), generally indicated higher overall uptake levels of L-[18F]FDOPA, compared to D-[18F]FDOPA. While in vivo PET imaging and ex vivo biodistribution studies in PC12, STC-1 and COLO-320 mouse xenografts further supported our in vitro data, they also illustrated lower off-target retention and enhanced clearance of D-[18F]FDOPA from healthy tissues. Cumulatively our results indicate the potential diagnostic applications of D-[18F]FDOPA for malignancies where the utility of L-[18F]FDOPA-PET is limited by the physiological uptake of L-[18F]FDOPA, and suggest D-[18F]FDOPA as a viable PET imaging tracer for NETs.

JEJUNAL ADENOCARCINOMA: A CASE REPORT

Tumors of the small intestine are extremely rare, and clinical signs and symptoms are nonspecific, resulting in prolongation of the diagnosis process and subsequently worsening the outcome of the treatment. In addition to non-specific symptomatology, additional difficulty in diagnosing is the very inaccessibility of the jejunum through endoscopic techniques. The following is a review of the case of a female patient with jejunum carcinoma. CASE REPORT. A 64-year-old patient with nonspecific symptoms of fatigue, weight loss and sore pain in the stomach initially hospitalized due to anemic syndrome. An endoscopic evaluation was performed, and the fining was chronic gastritis. The patient was prescribed with iron supplementation therapy and was sent home. Within a month, the fore mentioned symptoms started to intensify, and the patient was hospitalized at the General Hospital in Skopje, where extensive investigations were conducted. Upper digestive endoscopy was made, and the finding again only showed chronic gastritis. Due to lack of findings, the doctors performed abdominal ultrasonography that indicated only a bolded intestinal segment with a thick wall of 9mm in the projection of the left flexure to the descending colon. The need for additional investigations grew and computed tomography with contrast of the abdomen and small pelvis was performed. The finding of the computed tomography was in favor of an irregular intestinal segment in the projections of the jejunal convolutions, with a thickened heterogenic wall and pathological post-contrast coloring. Due to the need for correlation with other trials, MRI was performed, and its finding was highly suspected of a tumor change in the jejunum, but an inflammatory disease was not excluded. Because of this finding, the patient was sent to the Department of Digestive Surgery at the same facility. From a surgical point of view, the patient was treated with an upper medial laparotomy, which made it possible for the tumor to be released from its surroundings. The surgery and after surgery course and the patient’s condition were all as expected. The patient was in a stable general condition after the surgery, and she was sent home. The pathophysiological finding resulted in jejunal adenocarcinoma (Latin adenocarcinoma intestinijejuni). After the pathophysiological finding was obtained, the patient was referred to an oncologist for eventual adjuvant therapy. DISCUSSION. Small intestine carcinoma is a specific clinical and surgical entity, which is often diagnosed in an already overdue phase. This is due in part to the non-cohesive symptomatology, but largely due to the still insufficiently sophisticated detection methods. Because of this enigmatic nature of these carcinomas, it may be necessary to think of a special team in the digestive surgery departments, which would solely work on this pathology, in order to speed up diagnosis and improve the outcome of the treatment for the patient.

Intestinal obstruction caused by primary adenosquamous cell carcinoma of the small intestine: A case report and review of the literature.

Primary adenosquamous cell carcinoma (ASCC) arising from the ileum is an exceptionally rare malignant neoplasm exhibiting mixed glandular and squamous differentiation. The clinicopathological characteristics of ASCC have not been clearly determined due to its rarity. We herein report a case of a 74-year-old man with a successfully treated ASCC of the ileum. The patient visited a medical clinic due to abdominal pain. Abdominal computed tomography imaging revealed an intestinal tumor in the ileum. Prior to undergoing capsule endoscopy, the patient complained of severe abdominal pain due to intestinal obstruction from the patency capsule and the tumor. Thus, the patient was referred to our hospital for emergency surgery. Upon relieving the obstruction by partial resection of the ileum, an impacted patency capsule with a tumor with ulceration was identified. On histological examination, the tumor consisted of malignant glandular and squamous cell elements. The postoperative course was uneventful, without complications. The patient subsequently received adjuvant chemotherapy with oxaliplatin and capecitabine for 6 months. The patient has no evidence of recurrence 20 months after surgery. To the best of our knowledge, only 8 cases of ASCC have been reported in the English literature to date. This case serves as an important reminder to consider small intestinal carcinoma, including ASCC, in the differential diagnosis of intestinal obstruction.

Epithelial RNase H2 Maintains Genome Integrity and Prevents Intestinal Tumorigenesis in Mice

Background & AimsRNase H2 is a holoenzyme, composed of 3 subunits (ribonuclease H2 subunits A, B, and C), that cleaves RNA:DNA hybrids and removes mis-incorporated ribonucleotides from genomic DNA through ribonucleotide excision repair. Ribonucleotide incorporation by eukaryotic DNA polymerases occurs during every round of genome duplication and produces the most frequent type of naturally occurring DNA lesion. We investigated whether intestinal epithelial proliferation requires RNase H2 function and whether RNase H2 activity is disrupted during intestinal carcinogenesis.MethodsWe generated mice with epithelial-specific deletion of ribonuclease H2 subunit B (H2bΔIEC) and mice that also had deletion of tumor-suppressor protein p53 (H2b/p53ΔIEC); we compared phenotypes with those of littermate H2bfl/fl or H2b/p53fl/fl (control) mice at young and old ages. Intestinal tissues were collected and analyzed by histology. We isolated epithelial cells, generated intestinal organoids, and performed RNA sequence analyses. Mutation signatures of spontaneous tumors from H2b/p53ΔIEC mice were characterized by exome sequencing. We collected colorectal tumor specimens from 467 patients, measured levels of ribonuclease H2 subunit B, and associated these with patient survival times and transcriptome data.ResultsThe H2bΔIEC mice had DNA damage to intestinal epithelial cells and proliferative exhaustion of the intestinal stem cell compartment compared with controls and H2b/p53ΔIEC mice. However, H2b/p53ΔIEC mice spontaneously developed small intestine and colon carcinomas. DNA from these tumors contained T>G base substitutions at GTG trinucleotides. Analyses of transcriptomes of human colorectal tumors associated lower levels of RNase H2 with shorter survival times.ConclusionsIn analyses of mice with disruption of the ribonuclease H2 subunit B gene and colorectal tumors from patients, we provide evidence that RNase H2 functions as a colorectal tumor suppressor. H2b/p53ΔIEC mice can be used to study the roles of RNase H2 in tissue-specific carcinogenesis.

The application value of capsule endoscopy in diagnosing small intestinal carcinoma.

The aim of this study was to explore the clinical value of capsule endoscopy in the diagnosis of small intestine neoplastic lesions. A retrospective analysis was conducted on the clinical data of 108 patients who underwent capsule endoscopic examination in the Endoscopy Center of Xinxiang Central Hospital from February 2010 to January 2014. The characteristics of different small bowel diseases were observed, and the prevalence rates of different small bowel lesions were calculated. Of the included 108 patients who received capsule endoscopic examination, 74 cases showed lesions, with a detection rate of 68.52%. Of these 74 patients, 56 cases (51.85%) suffered from small bowel diseases and 18 cases (16.67%) were manifested with other gastrointestinal lesions. Moreover, obvious lesion was not observed in 34 cases (31.48%). Among the patients with lesions, we observed seven cases of submucosal tumor in small intestines, five cases of small intestinal carcinoma, two cases of small intestinal polyps, two cases of small intestinal roundworm, eight cases of small intestine ulcer, one case of Crohn's disease, 18 cases of enteritis, two cases of small intestine diverticula, four cases of small intestine hemangioma, one case of small intestine vascular malformation, one case of intestinal lymphangiectasia, one case of small intestine compression, two cases of small intestine hemorrhage, and two cases of small intestinal lipoma. Among the patients who showed other gastrointestinal lesions, we observed one case of esophageal diverticula, three cases of gastric erosion, six cases of superficial gastritis, four cases of gastric ulcer, one case of pyloric ulcer, one case of colonic polyps, and two cases of colon tumor. Capsule endoscopy demonstrated a high diagnostic value for various small bowel diseases, including both tumor and inflammatory lesions. Given its simplicity, safety, and reliability, capsule endoscopy was an important examination tool for the diagnosis of small bowel diseases.

Small Intestine Carcinoma with Multiple Metastasis Presenting as a Small Bowel Obstruction Due to a Dried Plum Stone：Report of a Case

Small Intestine Carcinoma with Multiple Metastasis Presenting as a Small Bowel Obstruction Due to a Dried Plum Stone：Report of a Case

Multifocal sarcomatoid carcinoma of small intestine with osteogenic differentiation: report of a case

Multifocal sarcomatoid carcinoma of small intestine with osteogenic differentiation: report of a case

Enterohepatic Helicobacter spp. in cats with non-haematopoietic intestinal carcinoma: a survey of 55 cases.

Several enterohepatic Helicobacter spp. (EHS) have been isolated from cats. Despite the reported association between EHS infection and intestinal neoplasia in other species, this association has not been explored in cats. In this study, 55 non-haematopoietic feline intestinal carcinoma cases were histopathologically evaluated. In contrast with prior reports, large intestinal (LI) carcinoma was observed with greater frequency (61 %) relative to small intestinal (SI) carcinoma (35 %). There was a significant association between intestinal location and animal gender. Of males examined, 83 % had LI carcinoma, while no such trend was observed in females. Previously described associations between Siamese breed and intestinal carcinoma could not be definitively confirmed, although the Siamese breed may be predisposed to SI carcinoma location. Of all carcinomas examined in this study, 62 % were classified as adenocarcinoma, although mucinous adenocarcinoma (28 %) and solid carcinoma (11 %) were also identified. Tumours were all moderately or poorly differentiated. When considered by intestinal location and histopathologic classification, LI adenocarcinoma was associated with significantly advanced mean age (13 years) when compared to SI adenocarcinoma and LI mucinous adenocarcinoma (mean, 9 years in both cases), which were also frequently encountered. To determine whether EHS might play a role in feline intestinal neoplasia, Helicobacter genus- and species-specific fluorescence in situ hybridization was performed. Of these carcinoma cases, 56 % were positive for Helicobacter spp. and one or more species-specific assay for Helicobacterbilis, Helicobactercanis or Helicobactermarmotae. The presence of EHS was significantly associated with both LI location (68 %) and mucinous adenocarcinoma (92 %). These findings suggest a role for intestinal bacteria in non-haematopoietic feline intestinal neoplasia.