Comparison of CT colonography, colonoscopy, sigmoidoscopy and faecal occult blood tests for the detection of advanced adenoma in an average risk population

BACKGROUND AND AIMS

This prospective trial was designed to compare the performance characteristics of five different screening tests in parallel for the detection of advanced colonic neoplasia: CT colonography (CTC), colonoscopy (OC), flexible sigmoidoscopy (FS), faecal immunochemical stool testing (FIT) and faecal occult blood testing (FOBT).

METHODS

Average risk adults provided stool specimens for FOBT and FIT, and underwent same-day low-dose 64-multidetector row CTC and OC using segmentally unblinded OC as the standard of reference. Sensitivities and specificities were calculated for each single test, and for combinations of FS and stool tests. CTC radiation exposure was measured, and patient comfort levels and preferences were assessed by questionnaire.

RESULTS

221 adenomas were detected in 307 subjects who completed CTC (mean radiation dose, 4.5 mSv) and OC; 269 patients provided stool samples for both FOBT and FIT. Sensitivities of OC, CTC, FS, FIT and FOBT for advanced colonic neoplasia were 100% (95% CI 88.4% to 100%), 96.7% (82.8% to 99.9%), 83.3% (95% CI 65.3% to 94.4%), 32% (95% CI 14.9% to 53.5) and 20% (95% CI 6.8% to 40.7%), respectively. Combination of FS with FOBT or FIT led to no relevant increase in sensitivity. 12 of 45 advanced adenomas were smaller than 10 mm. 46% of patients preferred CTC and 37% preferred OC (p<0.001).

CONCLUSIONS

High-resolution and low-dose CTC is feasible for colorectal cancer screening and reaches sensitivities comparable with OC for polyps >5 mm. For patients who refuse full bowel preparation and OC or CTC, FS should be preferred over stool tests. However, in cases where stool tests are performed, FIT should be recommended rather than FOBT.

Comparison of dietary protein with an oral, branched chain-enriched amino acid supplement in chronic portal-systemic encephalopathy: a randomized controlled trial

A randomized study was conducted in 37 hospitalized patients at six cooperating hospitals in which protein-intolerant cirrhotic patients were fed increasing amounts of either dietary protein or a branched-chain enriched amino acid solution (BCAA) until they attained an intake of 80 gm protein per day or equivalent or until they developed stage 2 encephalopathy. All patients initially received 20 gm of dietary protein for 1 week, after which 20 gm of protein or BCAA were added weekly. Nitrogen balance improved from negative to positive in all patients in whom it was measured and increased equally in both groups. Seven of the 20 patients in the protein group and 1 of 17 in the BCAA group developed encephalopathy of stage 2 or greater (p less than 0.05). Changes in each component of the portal-systemic encephalopathy syndrome were compared, and differences were statistically significant for mental status grade (p less than 0.01), asterixis (p less than 0.05), Portal-systemic encephalopathy index (p less than 0.01), but insignificant for Number Connection Test, EEG or ammonia. Plasma amino acid profiles showed an increase in BCAA in the study group. Thus, oral BCAA supplements appear to induce positive nitrogen balance to approximately the same degree as an equivalent amount of dietary protein without inducing encephalopathy as frequently.

Overexpression of Dicer predicts poor survival in colorectal cancer

AIMS

The RNASE III endonuclease Dicer is one of the key enzymes of microRNA biogenesis. The influence of Dicer-expression in tumour cells on the prognosis of patients with several cancers has been studied with controversial results among different cancer types. To date no one has examined the effect of this biomarker on survival in colorectal carcinoma. Thus, we aimed to study the influence of Dicer expression on survival in colorectal cancer.

METHODS

We performed immunohistochemical analyses on formalin-fixed paraffin embedded (FFPE) cancer tissue with an antibody against the Dicer protein. Tumour material from 237 cases was available from patients with colorectal adeonocarcinomas with moderate differentiation (G2) and without evidence of lymph-node (N0) or distant metastasis (M0). Sixty-four cases were in T2 and 173 in T3 stages. A tissue microarray (TMA) was constructed with each tumour in triplicate. Each tumour was assigned to a scoring scale of 0-3, depending on the cytoplasmatic expression of Dicer. A Kaplan-Maier analysis was performed and the log-rank test was used for significance levels by using SPSS v.17 software.

RESULTS

The expression of Dicer in colorectal carcinoma shows a strong association with poor survival (cancer specific survival=CSS, p<0,001) as well as with reduced progression free survival (PFS, p<0,001). In the group with no Dicer staining there was no recorded relapse (0/15) compared with 10/18 relapses in the group with the strongest staining of Dicer.

CONCLUSIONS

Strong expression of the central microRNA biosynthesis enzyme Dicer predicts poor prognosis in patients with colorectal cancer. This is in line with investigations on prostate cancer. Contradictory, in breast, lung and ovary cancer Dicer has been shown to be a marker of good prognosis. Further studies on the cellular functions of Dicer need to address these issues.

Distal splenorenal shunt vs. portal-systemic shunt: current status of a controlled trial

A prospective controlled comparison of portal-systemic (PSS) and distal splenorenal shunts (DSRS) in cirrhotic patients who had survived hemorrhage from esophagogastric varices was undertaken 5 yr ago at five hospitals by the Boston-New Haven Collaborative Liver Group. The clinical and endoscopic criteria for massive hemorrhage were satisfied in 155 patients. Thirty-four patients were excluded, primarily because of uncontrolled hemorrhage. Thirty-four were rejected because the were poor operative risks and 21 because they did not satisfy criteria. Thirteen patients refused to participate; the remaining 53 were randomized; 29 to receive PSS and 24, DSRS. The two groups were similar in clinical, laboratory, and manometric characteristics. The DSRS group was older and tended to have had more previous hemorrhages. Followup ranged from 1 to 56 months (mean 21). After PSS, which was performed by 10 different surgeons, 6 patients died during the hospital admission (21%) compared to 2 after DSRS (12%). There were 6 late deaths in the PSS group and 4 in the DSRS group. Portal-systemic encephalopathy occurred in 5 of the 23 survivors of PSS (23%), and in 6 of the 19 who survived DSRS (32%. Two patients in the PSS group bled (9%), 1 after thrombosis and 1 after stenosis of the shunt. Three patients in the DSRS group bled (16%) and all had thrombosis of the shunt. PSS was associated with an unexplained but inordinately high operative mortality. Although the DSRS was accomplished with an acceptably low operative mortality, it was associated with frequent portal-systemic encephalopathy, shunt occlusion, and recurrent hemorrhage. Similar incidences of portal-systemic encephalopathy, shunt occlusion, and recurrent hemorrhage were observed in the PSS group. More patients and longer followup are necessary to determine which of these portal decompressive procedures is superior.

Artificial intelligence for detection of microsatellite instability in colorectal cancer-a multicentric analysis of a pre-screening tool for clinical application

BACKGROUND

Microsatellite instability (MSI)/mismatch repair deficiency (dMMR) is a key genetic feature which should be tested in every patient with colorectal cancer (CRC) according to medical guidelines. Artificial intelligence (AI) methods can detect MSI/dMMR directly in routine pathology slides, but the test performance has not been systematically investigated with predefined test thresholds.

METHOD

We trained and validated AI-based MSI/dMMR detectors and evaluated predefined performance metrics using nine patient cohorts of 8343 patients across different countries and ethnicities.

RESULTS

Classifiers achieved clinical-grade performance, yielding an area under the receiver operating curve (AUROC) of up to 0.96 without using any manual annotations. Subsequently, we show that the AI system can be applied as a rule-out test: by using cohort-specific thresholds, on average 52.73% of tumors in each surgical cohort [total number of MSI/dMMR = 1020, microsatellite stable (MSS)/ proficient mismatch repair (pMMR) = 7323 patients] could be identified as MSS/pMMR with a fixed sensitivity at 95%. In an additional cohort of N = 1530 (MSI/dMMR = 211, MSS/pMMR = 1319) endoscopy biopsy samples, the system achieved an AUROC of 0.89, and the cohort-specific threshold ruled out 44.12% of tumors with a fixed sensitivity at 95%. As a more robust alternative to cohort-specific thresholds, we showed that with a fixed threshold of 0.25 for all the cohorts, we can rule-out 25.51% in surgical specimens and 6.10% in biopsies.

INTERPRETATION

When applied in a clinical setting, this means that the AI system can rule out MSI/dMMR in a quarter (with global thresholds) or half of all CRC patients (with local fine-tuning), thereby reducing cost and turnaround time for molecular profiling.

Enriched branched-chain amino acid formula versus a casein-based supplement in the treatment of cirrhosis

An orally administered branched-chain amino acid (BCAA) rich supplement (T), Travasorb-Hepatic was compared to a casein based supplement (E), Ensure, in a randomized double-blind cross-over study in eight malnourished, stable cirrhotics unable to achieve a daily dietary protein intake of 1.0 g/kg. Doses of antiportal systemic encephalopathy drugs remained constant and a baseline 1000 kcal, 40 g dietary protein intake was encouraged. To this diet, supplemental protein was added in daily 20-g increments to a maximum of 60 g supplemental protein. Mental status, asterixis, and number connection tests were assessed daily and an antiportal systemic encephalopathy index calculated. There was no significant difference in the mean intake of dietary protein (T, 33.7 +/- 4.0 g; E, 26.7 +/- 10.8 g), supplemental protein (T, 43.1 +/- 8.3 g; E, 47.9 +/- 7.1 g), or N2 balance (T, 4.2 +/- 3.7 g; E, 3.4 +/- 4.4) between treatment trials. The antiportal systemic encephalopathy index improved on E, with no significant change in the BCAA:aromatic acid molar ratio. This ratio improved on T (1.02 +/- 2.0 to 2.7 +/- 1.1), but was not accompanied by improvement in the antiportal systemic encephalopathy index. The improved protein tolerance in both groups was not further increased by a highly enriched BCAA formula compared to one with a moderate BCAA content from a natural dietary protein source. Thus, both conventional casein-based supplements and enriched BCAA formulas are well tolerated and can be safely and effectively used as an integral part of diet therapy.

Serotonin enhances oestradiol production by hamster preovulatory follicles in vitro: effects of experimentally induced atresia

Preovulatory follicles from adult hamsters on the morning of pro-oestrus were used in this study. Serotonin stimulated oestradiol production by preovulatory follicles during a 5-h incubation in 1 ml Krebs-Ringer bicarbonate glucose medium containing isobutylmethylxanthine (0.1 mmol/l; IBMX) and androstenedione (1 mumol/l). The enhanced oestradiol production by serotonin was dependent on the dose of IBMX and androstenedione. Mianserin, a serotonin type-1 and serotonin type-2 receptor antagonists, prevented the serotonin-enhanced oestradiol production in a dose-dependent manner. Ketanserin, a specific serotonin type-2 receptor antagonist, was ineffective in blocking the action of serotonin, indicating that the effect of serotonin was mediated by the serotonin type-1 receptor. In the presence of androstenedione (1 mumol/l), serotonin was unable to enhance oestradiol production in isolated granulosa cells. It was also unable to enhance oestradiol production in early atretic follicles; atresia was induced experimentally by an injection of phenobarbital in order to prevent ovulation. The data indicate that serotonin stimulates oestradiol production by hamster preovulatory follicles in vitro. The mechanism of action of serotonin involves an intact healthy follicle, a serotonin type-1 receptor and possibly cyclic AMP. The increased oestradiol secretion might be related to increased androgen production by the follicle and increased permeability (leakiness) of the follicle to androstenedione which serves as substrate for aromatization to oestradiol by the granulosa cell.

Sertoli–Leydig cell tumours of the ovary and testis: a CGH and FISH study

We present two malignant cases of Sertoli-Leydig cell tumours (SLCT) of the testis and one ovarian SLCT with benign behaviour. The DNA copy number changes affected chromosome 1, 8, 9p, 10, 11, 12, 16, 19, 22 and X. The present study is the first molecular-cytogenetic analysis of Sertoli-Leydig cell tumours of the testis.

Standardized and quality-assured predictive PD-L1 testing in the upper gastrointestinal tract

As a result of the high approval dynamics and the growing number of immuno-oncological concepts, the complexity of treatment decisions and control in the area of cancers of the esophagus, gastroesophageal junction and stomach is constantly increasing. Since the treatment indication for PD-1 inhibitors that are currently approved in the European Union is often linked to the expression of PD-L1 (programmed cell death-ligand 1), the evaluation of tissue-based predictive markers by the pathologist is of crucial importance for treatment stratification. Even though the immunohistochemical analysis of the PD-L1 expression status is one of the best studied, therapy-relevant biomarkers for an immuno-oncological treatment, due to the high heterogeneity of carcinomas of the upper gastrointestinal tract, there are challenges in daily clinical diagnostic work with regard to implementation, standardization and interpretation of testing. An interdisciplinary group of experts from Germany has taken a position on relevant questions from daily pathological and clinical practice, which concern the starting material, quality-assured testing and the interpretation of pathological findings, and has developed recommendations for structured reporting.

Pressure shift freezing as potential alternative for generation of decellularized scaffolds

Background. Protocols using chemical reagents for scaffold decellularization can cause changes in the properties of the matrix, depending on the type of tissue and the chemical reagent. Technologies using physical techniques may be possible alternatives for the production grafts with potential superior matrix characteristics. Material and Methods. We tested four different technologies for scaffold decellularization. Group 1: high hydrostatic pressure (HHP), 1 GPa; Group 2: pressure shift freezing (PSF); Group 3: pulsed electric fields (PEF); Group 4: control group: detergent (SDS). The degree of decellularization was assessed by histological analysis and the measurement of residual DNA. Results. Tissue treated with PSF showed a decellularization with a penetration depth (PD) of 1.5 mm and residual DNA content of 24% ± 3%. HHD treatment caused a PD of 0.2 mm with a residual DNA content of 28% ± .4%. PD in PEF was 0.5 mm, and the residual DNA content was 49% ± 7%. In the SDS group, PD was found to be 5 mm, and the DNA content was determined at 5% ± 2%. Conclusion. PSF showed promising results as a possible technique for scaffold decellularization. The penetration depth of PSF has to be optimized, and the mechanical as well as the biological characteristics of decellularized grafts have to be evaluated.

Leydig cell tumors of the testis: a molecular-cytogenetic study based on a large series of patients

The genetic features of the uncommon Leydig cell tumors (LCT) are largely unknown. Consequently, it is of great importance to elucidate the pathogenesis of testicular germ cell tumors by cytogenetic and molecular biological investigations. The purpose of the present study was the examination of cytogenetic features of these tumors in a large series of LCT. It comprised formalin-fixed, paraffin-embedded tissue samples from 25 LCT to analyze the chromosomal constitution using comparative genomic hybridization (CGH). In most of the studied cases, the aberrant cell population was additionally defined by interphase fluorescence in situ hybridization (I-FISH). Our molecular-cytogenetic study indicates chromosomal imbalances in the majority of our cases (21/25, 84%). The most frequent findings were gain of chromosome X, 19 or 19p and loss on chromosome 8 and 16.

[Gynaecomastia and mammography (author's transl)]

The term gynaecomastia indicates an increase in the mass of the normally rudimentary male breast; morphologically there is hyperplasia and differentiation of the epithelial and mesenchymal breast components. Gynaecomastia is not a disease in itself, but a symptom of some underlying disease or the result of drugs. Of 2895 breast operations performed at the surgical clinic of the University of Göttingen, 2.97% were operations on men with gynaecomastia. Amongst 79222 mammograms in the Radiological Clinic of the University, there were 900 mammograms (1.14%) of 392 men with gynaecomastia. Most benign and malignant conditions in men are retromammary in localisation. For this reason clinical evaluation is frequently wrong. The use of mammography as an additional diagnostic method in men is therefore more important than it is in women. Systematic analysis of the mammograms performed on men has made possible a classification of gynaecomastia according to the radiological appearances: I Septal linear structures (8.5%), II Opacities of varying density and size (26.5%), III Circular, usually inhomogenous shadows (15.5%), IV Homogeneous, demarcated foci of varying size (35.5%), V Soft-tissue hyperplasia-pseudo-gynaecomastia (10%).

[Differential diagnosis of gynaecomastia in the mammogram (author's transl)]

The purely clinical examination of swelling in the region of the male mammary gland involves a high error quota and must, therefore, be supplemented by other methods. Mammography has proved to be a reliable diagnostic method in the differential diagnosis of diseases of the mammary gland in the male; this method is of great importance in a positive sense as well. Gynaecomastia, with its typical criteria, must first of all be excluded. This enables the doctor to differentiate between various forms of gynaecomastia and to classify them into a kind of scheme. In all patients over 25 years of age, a carcinoma must be suspected particularly in case of a unilateral finding.

Thrombus or tumor? A case report of a rare sarcoma entity: intimal sarcoma of the pulmonary arteries

BACKGROUND

Tumor embolism is a very rare primary manifestation of cancers and the diagnosis is challenging, especially if located in the pulmonary arteries, where it can mimic nonmalignant pulmonary embolism. Intimal sarcoma is one of the least commonly reported primary tumors of vessels with only a few cases reported worldwide. A typical location of this malignancy is the pulmonary artery. Herein, we present a case report of an intimal sarcoma with primary manifestation in the pulmonary arteries. A 53-year-old male initially presented with dyspnea. On imaging, a pulmonary artery embolism was detected and was followed by thrombectomy of the right ventricular outflow tract, main pulmonary artery trunk, and right pulmonary artery after ineffective lysis therapy. Complementary imaging of the chest and abdomen including a PET-CT scan demonstrated no evidence of a primary tumor. Subsequent pathology assessment suggested an intimal sarcoma further confirmed by DNA methylation based molecular analysis. We initiated adjuvant chemotherapy with doxorubicin. Four months after the completion of adjuvant therapy a follow-up scan revealed a local recurrence without distant metastases.

DISCUSSION

Primary pulmonary artery intimal sarcoma (PAS) is an exceedingly rare entity and pathological diagnosis remains challenging. Therefore, the detection of entity-specific molecular alterations is a supporting argument in the diagnostic spectrum. Complete surgical resection is the prognostically most important treatment for intimal cardiac sarcomas. Despite adjuvant chemotherapy, the prognosis of cardiac sarcomas remains very poor. This case of a PAS highlights the difficulty in establishing a diagnosis and the aggressive natural course of the disease.

CONCLUSION

In case of atypical presentation of a pulmonary embolism, a tumor originating from the great vessels should be considered. Molecular pathology techniques support in establishing a reliable diagnosis.

The impact of disease and species differences on the intestinal CLCA4 gene expression

The human chloride channel regulator, calcium-activated (CLCA) 4 is discussed as a driver of epithelial-to-mesenchymal transition as well as a biomarker for colorectal cancer (CRC) and ulcerative colitis. In contrast to humans, the Clca4 gene is duplicated in the mouse, a common model species to study gene functions. However, the relevance of the functional murine Clca4 variants in healthy and diseased intestine is largely unknown. Here, we characterized the spatiotemporal expression patterns of the murine Clca4a and Clca4b genes in the healthy intestinal tract as well as in dextran sulfate sodium (DSS)-induced colitis and colitis-associated colon cancer (CAC) mouse model using RT-qPCR and in situ-hybridization. Similarly, we analyzed expression of the human CLCA4 in healthy, inflamed and cancerous intestinal tracts at single cell level. Murine Clca4a and -4b but not the human CLCA4 were detected in small intestine enterocytes of the respective species. Conversely, healthy colonocytes expressed the human CLCA4 and its murine ortholog Clca4a but not the murine Clca4b. Under inflammatory conditions, de novo expression of Clca4b was observed with both murine homologs abundantly expressed in enterocytes adjacent to ulcerations. Neoplastic colonocytes expressed none or only minimal amounts of the CLCA4 homologs both in humans and mice, whereas adjacent non-neoplastic colonocytes strongly up-regulated the human or both murine homologs, respectively. Our results suggest marked species- and homolog-specific differences in the expression patterns of the three CLCA4 homologs. Moreover, all three seem to play a role in reactive, non-neoplastic colonocytes adjacent to ulcerated and neoplastic lesions. KEY MESSAGES: Human CLCA4 and murine Clca4a, but not Clca4b, are expressed in healthy colonocytes. Inflammation leads to a de novo expression of the murine Clca4b in colonocytes. Human and murine CLCA4 homologs are absent from neoplastic enterocytes. Human and murine CLCA4s are highly expressed in tumor-adjacent, reactive colonocytes.

Specific T-cell receptor beta-rearrangements of gluten-triggered CD8+ T-cells are enriched in celiac disease patients' duodenal mucosa

Celiac disease (CeD) is an autoimmune disorder affecting the small intestine with gluten as disease trigger. Infections including Influenza A, increase the CeD risk. While gluten-specific CD4+ T-cells, recognizing HLA-DQ2/DQ8 presented gluten-peptides, initiate and sustain the celiac immune response, CD8+ α/β intraepithelial T-cells elicit mucosal damage. Here, we subjected TCRs from a cohort of 56 CeD patients and 22 controls to an analysis employing 749 published CeD-related TCRβ-rearrangements derived from gluten-specific CD4+ T-cells and gluten-triggered peripheral blood CD8+ T-cells. We show, that in addition to TCRs from gluten-specific CD4+ T-cells, TCRs of gluten-triggered CD8+ T-cells are significantly enriched in CeD duodenal tissue samples. TCRβ-rearrangements of gluten-triggered CD8+ T-cells were even more expanded in patients than TCRs from gluten-specific CD4+ T-cells (p < 0.0002) and highest in refractory CeD. Sequence alignments with TCR-antigen databases suggest that a subgroup of these most likely indirectly gluten-triggered TCRs recognize microbial, viral, and autoantigens.

PD-L1 expression assessment in Angiosarcoma improves with artificial intelligence support

Tumoral PD-L1 expression is assessed to weigh immunotherapy options in the treatment of various types of cancer. To determine PD-L1 expression, each tumor cell needs to be assessed to calculate the percentage of PD-L1 positive tumor cells, called tumor proportion score (TPS). Pathologists cannot evaluate each cell individually due to time constraints and thus need to approximate TPS, which has been shown to result in low concordance rates. Decision quality could be improved by an AI-based TPS prediction tool which serves as a "second opinion". Establishing such a tool requires a certain amount of training data, which manifests a bottleneck for rare cancer types such as Angiosarcoma. To address this challenge, we developed and open sourced a pipeline that leverages pre-trained and generalist models to achieve strong TPS prediction performance on limited data. Pathologists were asked to reassess patients for which their TPS strongly disagreed with the AI's prediction. In many of these cases, pathologists updated their TPS score, improving their assessment, thus demonstrating the technical feasibility and practical value of AI-based TPS scoring assistance for rare cancers.

[An electronic communication aid with a large keyboard for artificial respiration patients in the intensive care unit]

An increasing number of patients under mechanical ventilation in ICUs suffers from being cut off from normal communication. The existing communication facilities, such as letter-boards, magnetic letters, pictograms, Yes-no-signals and attempts at written communication are very often insufficient or not to be mastered by the weakened ICU respirator patient. We, therefore, present an electronic communicator consisting of a keyboard with big push-buttons and an illuminated running-letter display. Up to one page of text can be stored in memory and recalled later as running or printed text. Initial experiences with the electronic communicator show that even weakened respirator patients with diminished sensomotoric abilities successfully manage to communicate with the staff.