Colorectal carcinogenesis in the Lynch syndromes and familial adenomatous polyposis: trigger events and downstream consequences.

Carcinogenesis encompasses processes that lead to increased mutation rates, enhanced cellular division (tumour growth), and invasive growth. Colorectal cancer (CRC) carcinogenesis in carriers of pathogenic APC (path_APC) and pathogenic mismatch repair gene (path_MMR) variants is initiated by a second hit affecting the corresponding wild-type allele. In path_APC carriers, second hits result in the development of multiple adenomas, with CRC typically emerging after an additional 20 years.

Adenomas from individuals with pathogenic biallelic variants in the MUTYH and NTHL1 genes demonstrate base excision repair tumour mutational signature profiles similar to colorectal cancers, expanding potential diagnostic and variant classification applications.

Background: Colorectal cancers (CRCs) from people with biallelic germline likely pathogenic/pathogenic variants in MUTYH or NTHL1 exhibit specific single base substitution (SBS) mutational signatures, namely combined SBS18 and SBS36 (SBS18+SBS36), and SBS30, respectively. The aim was to determine if adenomas from biallelic cases demonstrated these mutational signatures at diagnostic levels.

Methods: Whole-exome sequencing of FFPE tissue and matched blood-derived DNA was performed on 9 adenomas and 15 CRCs from 13 biallelic MUTYH cases, on 7 adenomas and 2 CRCs from 5 biallelic NTHL1 cases and on 27 adenomas and 26 CRCs from 46 non-hereditary (sporadic) participants.

Future of Acute Severe Ulcerative Colitis-A Narrative Review.

While corticosteroids have led to significant reduction in ASUC mortality over the last few decades, they are associated with significant side effects and up to 30% of patients have steroid refractory ASUC, which means we require safer and better therapies for patients with ASUC. Several salvage therapies have been proposed in guidelines; however, we lack high quality head-to-head randomised controlled trials to assess effectiveness and safety of these agents. Furthermore, the role of newer novel agents in ASUC management is unclear.

Menopausal hormone therapy: assessing associations with breast and colorectal cancers by familial risk.

Menopausal users of hormone replacement therapy (HRT) are at increased breast cancer risk and decreased colorectal cancer (CRC) risk compared with individuals who have never used HRT, but these opposing associations may differ by familial risk of breast cancer and CRC. We harmonized data from 3 cohorts and generated separate breast cancer and CRC familial risk scores based on cancer family history. We defined moderate or strong family history as a risk score of 0.

A Quantitative Analysis of Human and Material Resources for Endoscopy Services in Pacific Island Countries.

Aims: This study aims to evaluate the current state of endoscopy services in Pacific Island Countries (PICs) by quantifying human and material resources, including the number of trained endoscopists and nurses, the types of procedures performed, and the availability and maintenance of endoscopic equipment.

Methods And Results: A mixed methods survey was conducted in 2023, targeting doctors and nurses who participated in the WGO-FNU-ANZGITA endoscopy training program as well as non-participants. Survey invitations were sent through email, WhatsApp, and Facebook Messenger.

Long-Term Follow Up of Patients Treated for Inflammatory Bowel Disease and Cytomegalovirus Colitis.

Background: Pathological reactivation of latent Cytomegalovirus (CMV) is triggered by inflammation and immunosuppression; both present in the pathogenesis and treatment of Inflammatory Bowel Disease (IBD). Whether CMV reactivation is associated with escalating medical therapy, further hospital admissions, or worse clinical outcomes remains controversial. This study aimed to follow up IBD patients with an index episode of CMV colitis and analyse the clinical outcomes.

Cardiovascular disease and stroke following cancer and cancer treatment in older adults.

Background: Cancer survivors can be at risk of cardiovascular disease (CVD) because of either their malignancy or its treatment. Although studies linking cancer and CVD exist, few examine risk in older adults, the impact of cancer treatment, or the effect of aspirin on reducing risk in this cohort.

Methods: The authors conducted a secondary analysis of the Aspirin in Reducing Events in the Elderly (ASPREE) trial to investigate the impact of cancer and cancer treatment on a composite CVD end point comprising hospitalization for heart failure (HHF), myocardial infarction (MI), and stroke.

Adrenal tumours in patients with pathogenic APC mutations: a retrospective study.

Background: Adrenal tumours are associated with familial adenomatous polyposis (FAP). In the literature, most studies use the clinical definition of FAP (more than 100 adenomatous polyps found in endoscopic studies). However, not all patients that meet clinical criteria for FAP carry pathogenic mutations in the adenomatous polyposis coli (APC) gene, as there is genetic heterogeneity responsible for FAP with the polyposis sometimes explained by genetic and environmental factors other than pathogenic APC mutations.

Phenotype correlations with pathogenic DNA variants in the gene.

-associated polyposis (MAP) is an autosomal recessive disorder where the inheritance of constitutional biallelic pathogenic variants predisposes a person to the development of adenomas and colorectal cancer (CRC). It is also associated with extracolonic and extraintestinal manifestations that may overlap with the phenotype of familial adenomatous polyposis (FAP). Currently, there are discrepancies in the literature regarding whether certain phenotypes are truly associated with MAP.

Incidences of colorectal adenomas and cancers under colonoscopy surveillance suggest an accelerated "Big Bang" pathway to CRC in three of the four Lynch syndromes.

Background: Colorectal cancers (CRCs) in the Lynch syndromes have been assumed to emerge through an accelerated adenoma-carcinoma pathway. In this model adenomas with deficient mismatch repair have an increased probability of acquiring additional cancer driver mutation(s) resulting in more rapid progression to malignancy. If this model was accurate, the success of colonoscopy in preventing CRC would be a function of the intervals between colonoscopies and mean sojourn time of detectable adenomas.

Should I take aspirin? A qualitative study on the implementation of a decision aid on taking aspirin for bowel cancer prevention.

Objectives: Australian guidelines recommend 50-70 years consider taking aspirin to reduce their bowel cancer risk. We trialled a decision aid in general practice to facilitate the implementation of these guidelines into clinical practice. This publication reports on the qualitative results from the process evaluation of the trial.

Benefits and Challenges of Treat-to-Target in Inflammatory Bowel Disease.

There is notable disparity between symptomatology and disease activity in a significant proportion of patients with inflammatory bowel disease (IBD), and escalation of treatment based on symptoms alone can fail to significantly alter the course of disease. The STRIDE-II position statement, published in 2021 by the Selecting Therapeutic Targets in Inflammatory Bowel Disease (STRIDE) initiative of the International Organisation for the Study of IBD (IOIBD) provides the most current recommendations for a treat-to-target (T2T) approach in IBD. Despite the benefits offered by a T2T approach in IBD, there are numerous drawbacks and current limitations to its widespread implementation in real-world clinical practice.