Introduction

The United Kingdom National Institute for Health and Care Excellence recommends Faecal Immunochemical Testing (FIT) for all patients presenting to primary care with symptoms suggestive of colorectal cancer. How use of this test varies across England is unknown, which this study aimed to quantify.

Aims & Methods

Routinely-collected primary care records (Clinical Practice Research Datalink Aurum) were used to assess variations in symptomatic FIT use in adults (≥18 years) between regions and over time in England from 2019 to 2023. Rates were calculated using the population registered to each primary care practice as the denominator, with analysis split by calendar year.
The first coded FIT test with a numerical result per patient each year was extracted from the primary care records. Rates of testing were calculated using Poisson regression, adjusted for other confounders. Results were described between groups, regions and years at the recommended threshold of ≥10 µgHb/g faeces (results above this threshold henceforth referred to as FIT10), describing the proportions likely to have a secondary care referral based on national guidance. Logistic regression was used to compare the impact of year, region, gender and age on the differences in FIT10.

Results

Between 01/01/2019 and 05/06/2023 there were 531,735 FIT results among 495,121 patients and a denominator population of 17,910,681. The number of completed FITs increased from 8,395 in 2019 to 237,708 in 2022 (the last complete year within the study), with a corresponding ~thirty-fold increase from 0.69 tests per 1000 person-years in 2019 (95%CI 0.68-0.71) to 19.57 per thousand person-years in 2022 (95%CI 19.50-19.65). There was large variation in testing between regions, with rates 3.6 times higher in the North East compared to the West Midlands (17.05 per thousand person-years, 95%CI 16.87-17.23 versus 4.72 per thousand person-years, 95%CI 4.67-4.76). These differences persisted to 2022, with less than half the rate in the West Midlands (11.32) compared to the North East (31.85 per thousand person-years).
20.4% of results were FIT10. Despite increased testing, the overall proportion FIT10 did not change over time. 51.7% of all tests FIT10 were in those over 70 years of age. The percentage FIT10 was lower in regions with higher rates of FIT testing, for example FIT10 ranged from 16.7% in the South West (rate of testing 14.62 per thousand person-years) to 25.3% in the South East (rate of testing 8.00 per thousand person-years). After adjusting for year, region, gender and age, this difference persisted (adjusted OR 0.57, 95%CI 0.55-0.58) comparing FIT10 in the South West to the South East. The difference in proportions FIT10 between regions showed some convergence over time, from a range of 16.6%-26.7% (10.1%) in 2021 to 15.8%-23.7% (7.9%) in 2023.

Conclusion

There has been a marked increase over time in the use of FIT for patients with symptoms in primary care, with large and persistent variations between regions of England. The overall proportion FIT10 has not decreased over time with increasing use, however there were large differences in FIT10 between regions that correlated with rates of testing. These regional differences persisted but reduced over time as testing rates increased nationally. It is likely that clinical pathway differences in the implementation of FIT over time and between regions explain the variations we have observed. If used as a guide to referral, such variation could lead to inequalities in colorectal investigation and diagnosis.

Introduction

Colonoscopic surveillance reduces colorectal cancer (CRC) incidence and mortality in Lynch syndrome (LS) carriers. Still, its invasiveness and high costs highlight the need for a non-invasive approach to predict the presence of neoplastic lesions.

Aims & Methods

This study aimed to identify faecal bacterial biomarkers to discern between carriers with colorectal lesions and those with normal colon.
Two independent Spanish cohorts (a training and a validation cohort) were recruited through two multicenter studies (Table 1). Participants provided a faecal sample before surveillance colonoscopy to quantify the abundance of F. prausnitzii (FPRA) and its phylogroups I and II (PHGI and PHGII), P. stomatis (PTST), B. fragilis (BCTF), B. thetaiotaomicron (BCTT), B46 (best BLAST match S. variabile), G. morbillorum (GMLL), B48 (best BLAST match R. faecis), and E. coli (ECO) through qPCR. Eubacteria (EUB) was quantified as the total bacterial load. Participants were classified based on colonoscopy findings as normal colonoscopy (NC), non-advanced adenoma (NAA), and advanced neoplasia (AN, including advanced adenoma and CRC). A bacterial signature for neoplasia prediction was defined and validated in the training and validation cohorts, respectively.

Table 1. Main characteristics of the study participants. NC, normal colonoscopy; NAA, non-advanced adenoma; AA, advanced adenoma; CRC, colorectal cancer.

Results

The bacterial abundances were analysed in the training cohort according to age, sex, body mass index (BMI), germline mutation, and colonoscopy findings. Significant moderate positive correlations were identified between the abundances of BCTF and age (r=0.325, p=0.040), and PHGII and BMI (r=0.399, p=0.010). A significant negative correlation was identified between GMLL abundance and BMI (r=-0.331, p=0.036). Patients harbouring MLH1 mutations exhibited a significantly higher abundance of FPRA compared to PMS2 carriers (p=0.048). Patients with neoplasia (NAA+AN) presented significantly lower abundances of BCTF (p=0.027) and B48 (p=0.038) than patients with NC. Patients with AN presented a significantly lower abundance of PTST compared to patients with NC or NAA (p=0.032).
Although all the bacterial markers achieved a sensitivity of 100% to predict the presence of neoplasia, none of them presented a specificity higher than 25% by itself. To maintain sensitivity and increase specificity a bacterial signature was defined including ECO, BCTF, GMLL, FPRA, PHGI, PHGII, and B46 combined with the inherited mutation. The signature showed 100% sensitivity (SS), 52.50% specificity (SP), 34.48% positive predictive value (PPV), and 100% negative predictive value (NPV). This signature was subsequently validated demonstrating 100% SS, 56.45% SP, 53.44% PPV, and 100% NPV.

Conclusion

A new faecal bacterial signature to predict the presence of colorectal neoplasia in LS carriers has been identified, showcasing its potential usefulness to improve and personalise LS surveillance, optimising endoscopic resources, and providing a less invasive and cost-effective approach.

Disclosure

S. Taboada-López, M. Malagón, S. Ramió-Pujol and M. Serra-Pagès are employees of GoodGut.

Introduction

Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease with the lowest 5-year survival rate of all cancers due to late diagnosis and lack of effective treatment. One of the challenges of developing molecular diagnosis and molecular targeted therapy for PDAC is the “mismatch” between research models and patients.

Aims & Methods

This study aimed i) to identify common proteins among different research models and patients and accordingly ii) to identify potential hub proteins and signaling pathways involved in the PDAC pathogenesis by using proteomics-based system modeling of multimodal datasets derived from multiple research models and patients. Mouse PDAC cells (derived from a genetically engineered mouse model with KrasG12D/Pdx1-Cre), PDAC orthotopically tumors in C57B/L6 mice (n=5), mouse PDAC spheroids, mouse pancreatic organoids, mouse PDAC organoids, normal mouse pancreatic tissues (n=5), human PDAC tumor tissue samples from treatment-naїve (n=20), neoadjuvant chemotherapy (n=22), and human PDAC organoids were included. Mass spectrometry-based proteomics, Rstudio, Cytoscape 3.10 and pathway enrichment analysis (using ingenuity pathways analysis, including human PDAC transcriptomic in addition) were used.

Results

In the comparison of PDAC models and patients, shared proteins were identified as follows: 60% between the mouse PDAC cells and the mouse PDAC spheroids, 78% between the mouse PDAC cells and the mouse PDAC tissue, 56% between the mouse PDAC spheroids and the mouse PDAC tissue, 66% between the mouse PDAC cells and the mouse PDAC organoids, 54% between the mouse PDAC spheroids and the mouse PDAC organoids, 38% between the mouse PDAC and the human PDAC tissues, 31% between the human PDAC tumor and the human PDAC organoids, and 60% between the mouse and the human PDAC organoids. A total of 1,367 common proteins were identified within all the PDAC models. Among these proteins ACTB, HSP90AA1, HSPA8, HSP90AB1, HSPA4, EEF2, RPS3, RPS20 and GAPDH were the top 10 hub proteins (with >300 node connections). Upon comparison of all eight models, eight proteins were identified as unique to PDAC, namely FAHD1, ARSA, NEK9, SERPINB9, LAMTOR2, SNRPG, TMED3, and RAB1A. There was a correlation in terms of z-score regarding signaling pathways between the mouse PDAC and human PDAC (p<0.001), particularly in activations of nerve growth factor signaling, integrin signaling, and neuregulin signaling. Central hub proteins commonly found in the mouse models included vinculin (membrane-cytoskeletal protein) as one of the high connectivity nodes and β-catenin and probable ubiquitin carboxyl-terminal hydrolase FAF-X (involved in axonal growth and neuronal cell migration) as high centrality nodes. In patients, central hub proteins that were dysregulated after chemotherapy included 14-3-3 protein zeta/delta (encoded by YWHAZ gene), β-catenin and SRC. Among the 47 proteins that were associated with altered metabolism after the chemotherapy in patients, CD44, CTNND1, APOA 1, PARVA, and SCRBS1 were nodes with low degrees, and desmosomes (DSP, KP3, PPL), PRTN3, thrombospondin-2 (THBS2), and DMBT1 were the most down-regulated proteins without nodes, and APOA1, caveolin-1 (encoded by CAV1), LRP1 were the most up-regulated proteins with nodes.

Conclusion

The system modeling identified the common proteins among the research models and patients and the hub proteins and signaling pathways, suggesting the potential translational targets of PDAC.

Clinical Case Summary

A 24-year-old male presented with jaundice and mild vertigo after a 10-day prodrome (asthenia, nausea, headache, fever). Ibuprofen (1200 mg/d) was taken for these symptoms only during the first 5 days. Labs revealed acute hepatocellular injury and elevated cholestasis (AST 215, ALT 862, FA 134, GGT 126 IU/L), marked mixed hyperbilirubinemia (Total 13.5 mg/dL, Direct 7.58 mg/dL) and coagulopathy (INR 1.59). Ultrasound showed hepatosplenomegaly. Viral hepatitis (HAV/HBV/HCV/CMV) and autoimmune/metabolic causes were excluded. Epstein-Barr Virus (EBV) serology showed low-titer positive VCA IgM but negative VCA IgG, EBNA IgG, and serum EBV DNA PCR, indicating recent non-active infection. Given ibuprofen timing and high RUCAM score, drug-induced liver injury (DILI) with a hepatocellular pattern was suspected. Liver biopsy confirmed acute hepatitis with lymphomonocytic infiltrate, necrosis and canalicular cholestasis. Despite improving liver function tests post-ibuprofen cessation, he developed worsening vertigo, severe ataxia, nausea, vomiting, hypophonia, necessitating nasogastric feeding/bed confinement. Cerebrospinal fluid (CSF) showed mild mononuclear pleocytosis (16 cells/mm³); a multiplex PCR pathogen panel (including EBV) was negative. Brain MRI/EEG were normal. Post-infectious EBV acute cerebellar ataxia was diagnosed concurrently with DILI, based on timing post-recent EBV, exclusion of active neurological infection (negative CSF PCR, normal imaging), mild pleocytosis, and supported by later IgG seroconversion. IV methylprednisolone treatment, chosen for clinical severity, led to significant neurological improvement within days and eventual recovery after physiotherapy. This case highlights the significant challenges of diagnosis and management of concomitant DILI and recent EBV infection with neurological sequelae, requiring careful differentiation of liver damage patterns (hepatocellular DILI vs cholestatic EBV) and optimal management of neurological symptoms.

References

Illustrative Material References:
- Liver biopsy histology slides (highlighting lymphomonocytic infiltrate, necrosis, and canalicular cholestasis characteristic of DILI).
- Table/Graph showing serial Liver Function Tests (AST, ALT, Bilirubin) over time, depicting injury peak and recovery trend.
- Table summarizing sequential Epstein-Barr Virus (EBV) serology results (VCA IgM, VCA IgG, EBNA IgG) demonstrating seroconversion.
- Table summarizing Cerebrospinal fluid (CSF) analysis results (cell count, protein, glucose, negative multiplex PCR).
- Representative Brain MRI images (axial/sagittal views) confirming absence of structural lesions or encephalitis signs.

Introduction

An increased risk of pancreatic cancer has been reported in families with breast cancer history carrying BRCA1 and BRCA2 mutations. Pancreatic cancer is associated with familial and hereditary cancer syndromes. Multigene panel testing for pancreatic cancer detected germline variants BRCA1/2, PALB2, ATM, TP53, MLH1, STK11/LKB1, APC, CDKN2A, and SPINK1/PRSS1 as high-risk genes. Active pancreatic surveillance using computed tomography (CT), magnetic resonance imaging (MRI), and echoendoscopic (EE) are recommended for high-risk individuals who have a family history of pancreatic cancer or harbor these pathogenic germline variants to improve the detection rate and the prognosis of pancreatic cancer. We evaluated the performance characteristics of echoendoscopically guided fine needle biopsy (EE-FNB) in this subset of patients.

Aims & Methods

This is a retrospective analysis of a prospective database total of 99 families with ≥1 case of breast cancer tested for mutations in BRCA1 and/or BRCA2. The eligible patients were the ones that underwent EE-FNB at a tertiary hospital with an Oncology center due a focal pancreatic lesion observed on CT/MRI, from January 2022 to January 2024. Patients were excluded if (1) they had obstructive jaundice or (2) the lesion appeared cystic on CT/MRI. The main outcome measures were (1) prevalence of the association between BRCA 2 positive and pancreatic cancer (2) performance characteristics of EE-FNB for identification of malignancy.

Results

In the 99 patients in the study, a focal pancreatic lesion was identified with pancreatic adenocarcinoma by EE-FNB. The final diagnosis included 20 patients with breast cancer and BRCA2 positive undergoing oncological treatment or follow-up, with a mean age of 32.8 +/- 2.2 years. EE was performed in an average of 19 +/- 11.3 days. EE-FNB showed an accuracy of 100% for the diagnosis of malignant neoplasia, with a sensitivity of 100%, specificity of 100%.

Conclusion

EE-FNB diagnostic yield was substantial in established high-risk mutation carriers, is highly accurate in patients with focal pancreatic lesion on CT/MRI, without obstructive jaundice. EE-FNB can potentially be used as a definitive diagnostic test in the management of these patients.

Introduction

Thiopurines are vital therapeutic agents for inflammatory bowel diseases but often cause severe myelosuppression. The NUDT15 polymorphism, particularly p.Arg139Cys (NUDT15R139C), is strongly linked to severe leukocytopenia and is prevalent in Asian populations. Despite thiopurine use during pregnancy, it remains unclear if NUDT15R139C affects fetal thiopurine sensitivity.

Aims & Methods

The human and murine NUDT15 proteins share 89% homology with the preservation of arginine at codon 139 of human NUDT15 in codon 138 of murine Nudt15. We established a knock-in mouse model with a point mutation (c.412C>T) generating p.Arg138Cys (Nudt15^R138C), mimicking the human phenotype. In the current study, we investigated offspring generated from Nudt15^+/R138C or Nudt15^+/+ female mice that were mated with Nudt15^+/R138C male mice and simultaneously administered with mercaptopurine (MP).To evaluate the effects of thiopurine on the fetus, we evaluated the number of hematopoietic stem cells in the fetal liver, which is the center of fetal hematopoiesis.

Results

In administration with the tolerable MP dose (0.5 mg/kg) for adult Nudt15^+/R138C mice, genotypes of the genotypes of neonatal mice born from breeding between Nudt15^+/R138 male mice and Nudt15^+/R138 female mice were 35 (37.2%) Nudt15^+/+, 59 (62.8%) Nudt15^+/R138C, and 0 Nudt15 ^R138C/R138C. On embryonic day 14.5, Nudt15^R138C/R138C fetal mice showed shorter body lengths and fewer hematopoietic stem cells in the fetal liver than Nudt15^+/+ fetal mice. The number of fetal HSCs was not altered in any of the Nudt15genotypes without MP treatment. However, it was significantly reduced by MP treatment in Nudt15^+/R138C fetal mice (p< 0.01, mean number 1104 in DMSO and 577 in MP) and in Nudt15^R138C/R138C fetal mice (p< 0.01, mean number 927 in DMSO and 402 in MP), but not in Nudt15^+/+ fetal mice (p= 0.39, mean number 1004 in DMSO and 820 in MP). The number of HSCs in Nudt15^R138C/R138C fetal livers was significantly reduced to less than 50% of that in Nudt15^+/+ fetal livers by MP treatment during gestation (p= 0.0089). In administration with the tolerable MP dose (1.0 mg/kg) for Nudt15^+/+ adult mice, genotypes of neonatal mice born from breeding between Nudt15^+/R138 male mice and Nudt15^{++ /}female mice were 23 Nudt15^+/+ and 0 Nudt15^+/R138C. Without MP administration, neonatal mice were born in a Mendelian fashion.

Conclusion

Fetal toxicity may arise if the fetus has more NUDT15 R139C alleles than the mother, despite safe thiopurine doses for the mother. Analysis of the father's NUDT15 genotype may enable safer thiopurine use during pregnancy, emphasizing the importance of considering parental genotypes in therapeutic decisions.