Intratumor heterogeneity (ITH) of premalignant colorectal lesions is an important area of research for understanding the diverse biological behavior of colorectal cancer (CRC). Accurate assessment of ITH depends substantially on the sampling strategy used. We present a novel methodological approach termed whole tumor heterogeneity topography (WTHT) and compare it with three previously described sampling strategies: whole tumor homogenization, macrodissection of selected tumor regions, and multisampling. A cohort of 184 advanced precancerous colorectal lesions was processed into paraffin blocks, and the entire tumor mass was systematically divided into equally sized samples (~10 mm3). DNA was isolated from each sample separately and analyzed for hotspot mutations in APC, KRAS, BRAF, PIK3CA, and TP53. ITH was quantified using mutation variance and a newly introduced Heterogeneity Grade (HG). Results obtained by WTHT were statistically and graphically compared with three other modeled sampling strategies. Significant differences were observed among the analyzed sampling approaches. Macrodissection showed the greatest deviation from WTHT, indicating substantial sampling bias, whereas multisampling produced the closest results. WTHT enabled precise quantification and spatial mapping of mutational clones across the entire lesion. WTHT combined with HG provides a robust and reproducible framework for comprehensive assessment of ITH in colorectal adenomas.

Formou kazuistického sdělení prezentujeme případ recidivujícího krvácení z léze Dieulafoy v oblasti céka. Jedná se o vzácnou příčinu krvácení do dolního gastrointestinálního traktu klinicky se manifestující od drobného až po masivní krvácení s rozvojem mikrocytární anemie těžkého stupně vyžadujícího hospitalizaci a hemosubstituci. Diagnostika a terapie se opírá o endoskopické vyšetření dolní části zažívacího traktu a je značně limitována intermitentní povahou krvácení vedoucí mnohdy k falešně negativnímu nálezu. Léčba je založena na dosažení hemostázy využitím endoskopických metod jako opich adrenalinem, argon-plazma koagulace a využití hemoklipů. V dostupné literatuře bylo popsáno jen několik kazuistických případů výskytu Dieulafoy léze v tračníku. I při vzácném výskytu léze je potřebné na ni v rámci diferenciální diagnostiky anemie myslet, zejména v případech s negativním výsledkem prvotního endoskopického vyšetření.

Celiac disease is a systemic autoimmune affliction triggered by dietary gluten in genetically predisposed subjects. Current estimation of the prevalence of celiac disease is approximately 1% for the global population. These data are consistent with current figures from the Czech Republic (prevalence of 1.06% in 2023). Celiac disease can be associated with several complications including malignancy. Exact epidemiology data on T-cell lymphoma and small intestinal adenocarcinoma in the Czech Republic over the period 2010–2023 are also provided. Unlike the no-biopsy approach in children, despite current non-conclusive discussion and besides serology, upper gastrointestinal endoscopy, biopsies, and histology are mandatory for proper diagnosis and initial assessment of the severity of celiac disease in adults. However, there are so far no unified and integrated recommendations for the follow-up of adult celiac disease. Although the risk of malignancy in celiac disease is relatively low, especially in a strict gluten-free diet, it might nevertheless be further decreased by an individualized surveillance. Endoscopy controls with biopsies for histology, immunohistochemistry, and flow cytometry are essential. The purpose of this article was to review the risk and diagnostics of malignancy in celiac disease. A proposal for the individualized surveillance of premalignant gastrointestinal lesions in adult celiac disease was drafted.

We assessed the diagnostic performance of the Narrow-Band Imaging (NBI) International Colorectal Endoscopic Classification (NICE) and the Japan NBI Expert Team classification (JNET) in predicting histological outcomes of advanced colorectal lesions. Additionally, we evaluated the sensitivity and positive predictive value (PPV) of the JNET and NICE classifications individually for high-grade lesions (including HGD adenomas, intramucosal carcinomas, and T1 carcinomas). This was a retrospective analysis of prospectively collected data, involving 211 patients (130 men, mean age 60 years) who underwent colonoscopy with endoscopic resection of advanced colorectal neoplasia (lesions ≥ 10 mm). Lesions were classified using both NICE and JNET criteria, and final histopathological results were used for comparison. Of the 257 lesions analyzed, the NICE classification accurately classifies a large proportion of lesions (93.8%). In JNET classification we observed 77.4% correctly classified lesions. Specifically, the sensitivity and positive predictive value (PPV) of the NICE classification for high-grade lesions were 100% and 24.4%, respectively. For the JNET classification, the sensitivity and PPV for high-grade lesions were 56.6% and 57.7%, respectively. The JNET classification, with a positive predictive value of 57.7% for high-grade colorectal lesions (including HGD adenomas, intramucosal carcinomas, and T1 carcinomas), should be used for decision-making regarding appropriate subsequent endoscopic therapy.

Aims The National Colorectal Cancer (CRC) Screening Program was launched in the Czech Republic in 2000 as an opportunistic screening program. In 2014, this program was transformed into a population-based program by introducing an address invitation of the target population. This led to a significant increase in the participation rate of the target population in CRC screening. Due to the covid pandemic, overall participation significantly dropped during years 2020 and 2021. The main aim of the study was to evaluate the level of participation of the target population in the CRC screening program. Other objectives included evaluating the effectiveness of screening tests (FOBT, screening colonoscopy, FOBT-positive colonoscopy).

Aims After endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) for non-pedunculated lesions in GI tract the mucosal or submucosal defect is created. It can be treated by monopolar coagulation or clip closure. Recently new method using the self-assembling peptide (SAP) has been introduced. SAP forms the nanofibers web andthe extracellular matrix resulting in three outcomes: acute bleeding hemostasis, delayed bleeding reduction andimproved post-resection defect healing.

The National Colorectal Cancer Screening Program has been conducted in the Czech Republic since 2000 and serves as an example of interdisciplinary collaboration. Specialists from gastroenterology, general practice, gynecology, and clinical biochemistry are involved in the program. It is based on two primary methods: the screening fecal immunochemical test for occult bleeding (iFOBT, FIT) and preventive colonoscopy (FOBT-positive colonoscopy and screening colonoscopy). The program‘s effectiveness is evidenced by the high number of detected colorectal precancerous and malignant lesions. Between 2006 and 2023, a total of 531,362 preventive colonoscopies were performed, diagnosing 202,575 patients with adenomas (38.1%) and 14,473 patients with cancers (2.7%). Program quality is monitored by indicators focused on both organization (target population coverage) and screening methods. Coverage with screening tests in a 2-year interval has consistently ranged around 30%, except between 2020 and 2021 during the COVID-19 pandemic (27%), reaching 30.0% in 2023. Non-screening tests also affect epidemiological indicators, with total coverage by all relevant methods in a 2-year interval in 2023 amounting to 37.5%. Colonoscopies are evaluated using six parameters (number of examinations, bowel preparation quality, total colonoscopies, and adenoma detection rate in total, in both women and men). In 2023, 72% of screening colonoscopy centers met all of these indicators. FOBT analyzers now must have the regular external quality assessment (EQA), which should help stabilize test positivity, standing at 9.1% in 2023. Thanks to the National Colorectal Cancer Screening Program, favorable epidemiological trends have been observed, with a 32.3% decrease in incidence and a 47.8% decrease in mortality between 2000 and 2022. The future of the program lies in its further optimization, with a goal of both increasing coverage of the target population by examination and quality improvement, ensuring the program’s feasibility and efficiency. Key words: colorectal cancer – adenoma – screening – colonoscopy – fecal immunochemical test – quality indicators

Ustredni vojenska nemocnice - Vojenska fakultni nemocnice Praha, Czechia; Masarykova univerzita Institut biostatistiky a analyz, Czechia.