Androgen-mediated maternal effects and trade-offs: postnatal hormone development, growth, and survivorship in wild meerkats.

Introduction: Mammalian reproductive and somatic development is regulated by steroid hormones, growth hormone (GH), and insulin-like growth factor-1 (IGF-1). Based largely on information from humans, model organisms, and domesticated animals, testosterone (T) and the GH/IGF-1 system activate sexually differentiated development, promoting male-biased growth, often at a cost to health and survivorship. To test if augmented prenatal androgen exposure in females produces similar developmental patterns and trade-offs, we examine maternal effects in wild meerkats (Suricata suricatta), a non-model species in which adult females naturally, albeit differentially by status, express exceptionally high androgen concentrations, particularly during pregnancy. In this cooperative breeder, the early growth of daughters predicts future breeding status and reproductive success. Methods: We examine effects of normative and experimentally induced variation in maternal androgens on the ontogenetic patterns in offspring reproductive hormones (androstenedione, A4; T; estradiol, E2), IGF-1, growth from pup emergence at 1 month to puberty at 1 year, and survivorship. Specifically, we compare the male and female offspring of dominant control (DC or high-T), subordinate control (SC or lower-T), and dominant treated (DT or blocked-T) dams, the latter having experienced antiandrogen treatment in late gestation. Results: Meerkat offspring showed sex differences in absolute T and IGF-1 concentrations, developmental rates of A4 and E2 expression, and survivorship - effects that were sometimes socially or environmentally modulated. Atypical for mammals were the early male bias in T that disappeared by puberty, the absence of sex differences in A4 and E2, and the female bias in IGF-1. Food availability was linked to steroid concentrations in females and to IGF-1, potentially growth, and survival in both sexes. Maternal treatment significantly affected rates of T, E2, and IGF-1 expression, and weight, with marginal effects on survivorship; offspring of DT dams showed peak IGF-1 concentrations and the best survivorship. Discussion: Maternal effects thus impact offspring development in meerkats, with associated trade-offs: Whereas prenatal androgens modify postnatal reproductive and somatic physiology, benefits associated with enhanced competitiveness in DC lineages may have initial costs of reduced IGF-1, delay in weight gain, and decreased survivorship. These novel data further confirm the different evolutionary and mechanistic pathways to cooperative breeding and call for greater consideration of natural endocrine variation in both sexes.

Animal life in the shallow subseafloor crust at deep-sea hydrothermal vents.

It was once believed that only microbes and viruses inhabited the subseafloor crust beneath hydrothermal vents. Yet, on the seafloor, animals like the giant tubeworm Riftia pachyptila thrive. Their larvae are thought to disperse in the water column, despite never being observed there. We hypothesized that these larvae travel through the subseafloor via vent fluids. In our exploration, lifting lobate lava shelves revealed adult tubeworms and other vent animals in subseafloor cavities. The discovery of vent endemic animals below the visible seafloor shows that the seafloor and subseafloor faunal communities are connected. The presence of adult tubeworms suggests larval dispersal through the recharge zone of the hydrothermal circulation system. Given that many of these animals are host to dense bacterial communities that oxidize reduced chemicals and fix carbon, the extension of animal habitats into the subseafloor has implications for local and regional geochemical flux measurements. These findings underscore the need for protecting vents, as the extent of these habitats has yet to be fully ascertained.

Inequities in sleep duration and quality among adolescents in Canada.

BACKGROUND: Several recent global events may have impacted adolescent sleep and exacerbated pre-existing disparities by social positions (i.e., social roles, identity or sociodemographic factors, and/or group memberships that are associated with power and oppression due to the structures and processes in a given society at given time). Current understanding of sleep among adolescents is critical to inform interventions for a more equitable future, given the short and long-term consequences of inadequate sleep on health and well-being. This study aimed to provide contemporary evidence on sleep disparities by key social positions among adolescents in Canada. METHODS: Cross-sectional analyses were conducted using self-reported data collected during 2020-2021 (the first full school year after the COVID-19 pandemic onset) from 52,138 students (mean [SD] age = 14.9 [1.5]) attending 133 Canadian secondary schools. Multiple regression models were used to test whether sleep quality (how well students slept during past week), duration (weekday, weekend, weighted daily average), and guideline adherence (8-10 h/day) differed by sex and gender, race and ethnicity, and socioeconomic status (SES). RESULTS: Females reported a mean [95% CI] difference of -1.7 [-3.7, 0.4] min/day less sleep on weekdays than males, but 7.1 [4.5, 9.6] min/day more sleep on weekends, resulting in no difference in average daily sleep between males and females. Females were less likely to report good quality sleep compared to males (AOR = 0.57 [0.54, 0.60]). SES followed a generally monotonic trend where higher scores were associated with more sleep on weekdays (Δhighest: lowest = -28.6 [-39.5, -17.6]) and weekends (Δhighest: lowest = -17.5 [-3.8, -31.2]) and greater likelihood of higher sleep quality (AORhighest: lowest = 3.04 [2.35, 3.92]). Relative to White adolescents, weekday and average daily sleep duration were lower among all other racial identities; mean differences ranged from ∼ 5-15 min/day, with Black students reporting the least sleep. CONCLUSIONS: Differences in sleep duration and quality were most profound among adolescents from the lowest and highest SES. Racial disparities were more evident on weekdays. Compensatory weekend sleep appears more pronounced in females than males. Addressing sleep inequities is critical, as a robust predictor of multiple health outcomes.

Circulating Tumor DNA Predicts Early Recurrence Following Locoregional Therapy for Oligometastatic Colorectal Cancer.

(1) Background: Local therapies offer a potentially curative approach for patients with oligometastatic colorectal cancer (CRC). An evidence-based consensus recommendation for systemic therapy following definitive locoregional therapy is lacking. Tumor-informed circulating tumor DNA (ctDNA) might provide information to help guide management in this setting. (2) Methods: A multi-institutional retrospective study was conducted, including patients with CRC that underwent curative-intent locoregional therapy to an isolated site of metastatic disease, followed by tumor-informed ctDNA assessment. The Kaplan-Meier method and log-rank tests were used to compare disease-free survival based on ctDNA results. ctDNA test performance was compared to carcinoembryonic antigen (CEA) test results using McNemar's test. (3) Results: Our study cohort consisted of 87 patients treated with locoregional interventions who underwent ctDNA testing. The initial ctDNA test post-intervention was positive in 28 patients and negative in 59 patients. The median follow-up time was 14.0 months. Detectable ctDNA post-intervention was significantly associated with early disease recurrence, with a median disease-free survival (DFS) of 6.63 months compared to 21.30 months in ctDNA-negative patients (p < 0.001). ctDNA detected a numerically higher proportion of recurrences than CEA (p < 0.097). Post-intervention systemic therapy was not associated with improved DFS (p = 0.745). (4) Conclusions: ctDNA results are prognostically important in oligometastatic CRC, and further prospective studies are urgently needed to define its role in guiding clinical decisions.

The concentration of platelets in PRP does not affect pain outcomes in lateral epicondylitis: a systematic review and meta-analysis.

Aim: To investigate the analyze the relationship between concentration platelet-dose in platelet-rich plasma (PRP) injections and improvements in pain when treating lateral epicondylitis. Methods: A systematic review was conducted into five medical databases, exploring the difference in pain outcomes based on concentration of PRP. Results: Initial querying of the databases yielded 1408 articles with 20 articles ultimately included. There was no statistical significance between effect sizes of the two treatment groups (high and low platelet concentration; p = 0.976). Conclusion: Both large and small concentrations of platelets depict significant reduction in pain, however, between subgroups there was no significance. It can thus be concluded that concentration of platelets in PRP does not impact overall pain relief.

[Box: see text].

Co-expression analysis reveals distinct alliances around two carbon fixation pathways in hydrothermal vent symbionts.

Most autotrophic organisms possess a single carbon fixation pathway. The chemoautotrophic symbionts of the hydrothermal vent tubeworm Riftia pachyptila, however, possess two functional pathways: the Calvin-Benson-Bassham (CBB) and the reductive tricarboxylic acid (rTCA) cycles. How these two pathways are coordinated is unknown. Here we measured net carbon fixation rates, transcriptional/metabolic responses and transcriptional co-expression patterns of Riftia pachyptila endosymbionts by incubating tubeworms collected from the East Pacific Rise at environmental pressures, temperature and geochemistry. Results showed that rTCA and CBB transcriptional patterns varied in response to different geochemical regimes and that each pathway is allied to specific metabolic processes; the rTCA is allied to hydrogenases and dissimilatory nitrate reduction, whereas the CBB is allied to sulfide oxidation and assimilatory nitrate reduction, suggesting distinctive yet complementary roles in metabolic function. Furthermore, our network analysis implicates the rTCA and a group 1e hydrogenase as key players in the physiological response to limitation of sulfide and oxygen. Net carbon fixation rates were also exemplary, and accordingly, we propose that co-activity of CBB and rTCA may be an adaptation for maintaining high carbon fixation rates, conferring a fitness advantage in dynamic vent environments.

Drivers of antimicrobial resistance within the communities of Nepal from One Health perspective: a scoping review.

Background: A major driver of antimicrobial resistance (AMR) is the inappropriate use of antimicrobials. At the community level, people are often engaged in behaviors that drive AMR within human, animal, and environmental (One Health) impacts. This scoping review consolidates research to determine (a) the community's knowledge, attitudes, and practices around AMR; (b) existing community-based interventions; and (c) barriers and enablers to addressing AMR in Nepal. Methods: This scoping review follows the Joanna Briggs Institute scoping review methodology. Literature indexed in PubMed, Scopus, CINAHL, Global Index Medicus, HINARI-SUMMON, Embase (Ovid), Global Health (Ovid), CAB Abstracts (Ovid), Web of Science, and Google Scholar between January 2000 and January 2023 were reviewed for inclusion. Articles were included in the review if they considered the issues of AMR at the community level in Nepal; this excluded clinical and laboratory-based studies. A total of 47 studies met these criteria, were extracted, and analyzed to consolidate the key themes. Results: A total of 31 (66%) articles exclusively included human health; five (11%) concentrated only on animal health; no studies solely focused on environmental aspects of AMR; and the remaining studies jointly presented human, animal, and environmental aspects. Findings revealed inadequate knowledge accompanied by inappropriate practice in both the human and animal health sectors. Four community interventions improved knowledge and practices on the appropriate use of antimicrobials among community people. However, various social and economic factors were found as barriers to the appropriate use of antimicrobials in the community. Conclusion: Community engagement and One Health approaches could be key tools to improve awareness of AMR and promote behavioral change related to AM use in communities, as current studies have revealed inadequate knowledge alongside inappropriate practices shared in both human and animal health sectors. Systematic review registration: DOI: 10.17605/OSF.IO/FV326.

Exploring community insights on antimicrobial resistance in Nepal: a formative qualitative study.

BACKGROUND: Antimicrobial resistance (AMR) is the process by which microbes evolve mechanisms to survive the medicines designed to destroy them i.e. antimicrobials (AMs). Despite being a natural process, AMR is being hastened by the abuse of AMs. In context of Nepal, there is limited information on drivers of AMR and barriers in addressing it from a community perspective. This study explores the local language and terminology used around AMs in the community, commonly used AMs and reasons for their usage, how these AMs are sourced, and the perceived barriers to addressing AMR via One Health approach. METHODS: A phenomenological study design was utilized with applied qualitative research theoretically framed as pragmatism. Twelve in-depth interviews and informal discussions with a One Health focus, were purposively conducted with wide range of stakeholders and community resident of Kapilvastu municipality of Nepal during April 2022. The acquired data was analyzed manually via a thematic framework approach. The study obtained ethical approval from ethical review board of Nepal Health Research Council and University of Leeds. RESULTS: Nepali and Awadhi languages does not have specific words for AMs or AMR, which is understandable by the community people. Rather, community use full explanatory sentences. People use AMs but have incomplete knowledge about them and they have their own local words for these medicines. The knowledge and usage of AMs across human and animal health is impacted by socio-structural factors, limited Government regulation, inadequate supply of AMs in local government health facilities and the presence of various unregulated health providers that co-exist within the health system. Novel ideas such as the use of visual and smart technology, for instance mobile phones and social media exposure, can enable access to information about AMs and AMR. CONCLUSION: This study shows that terminology that is understandable by the community referring to AMs and AMR in Nepali and Awadhi languages does not exist, but full explanatory sentences and colloquial names are used. Despite regular utilisation, communities have incomplete knowledge regarding AMs. Since, knowledge alone cannot improve behaviour, behavioural interventions are required to address AMR via community engagement to co-produce their own solutions. TRIAL REGISTRATION: Not applicable.

Tumor-Informed Circulating Tumor DNA for Minimal Residual Disease Detection in the Management of Colorectal Cancer.

PURPOSE: Recurrence after curative-intent treatment occurs in 20%-50% of patients with stage II-IV colorectal cancer (CRC), underscoring the need for early detection of minimal residual disease (MRD) using circulating tumor DNA (ctDNA). Here, we examined the pattern of use of a tumor-informed ctDNA assay in CRC MRD monitoring in routine clinical practice at Mayo Clinic, Rochester. METHODS: We conducted a retrospective analysis of health records of patients with CRC who had at least one tumor-informed ctDNA assay from May 2019 through July 1, 2022. Recurrence was defined as radiographic evidence of disease. Descriptive characteristics of the cohort, ctDNA results, and subsequent interventions were recorded. RESULTS: Of the 120 patients included, the median age at diagnosis was 67 years, 46% were female, and 94% were White. At diagnosis, 10 patients had stage I, 23 stage II, 60 stage III, and 25 stage IV disease. Of 476 ctDNA assays performed, 70% were performed in patients who had recurrent disease most commonly to monitor the effectiveness of therapeutic interventions and 16% resulted in a change in clinical decision making. There were 110 recurrences identified in 62 patients, as some patients experienced more than one recurrence over time. Compared with serum carcinoembryonic antigen levels, ctDNA results correlated better with radiologic imaging. CONCLUSION: Routine ctDNA monitoring for MRD detection has been adopted in clinical practice; however, 84% of ctDNA assays performed did not result in a change in clinical management. This suggests the need for further clinical research data to guide routine clinical use of ctDNA MRD testing in CRC.

Addressing antimicrobial resistance through community engagement: a framework for developing contextually relevant and impactful behaviour change interventions.

Background: Community engagement (CE) interventions often explore and promote behaviour change around a specific challenge. Suggestions for behaviour change should be co-produced in partnership with the community. To facilitate this, it is essential that the intervention includes key content that unpacks the challenge of interest via multiple sources of knowledge. However, where community lived experience and academic evidence appear misaligned, tensions can appear within the co-production dynamic of CE. This is specifically so within the context of antimicrobial resistance (AMR) where ideal behaviours are often superseded by what is practical or possible in a particular community context. Methods: Here we describe a framework for the equitable development of contextually appropriate, clearly evidenced behavioural objectives for CE interventions. This framework explores different sources of knowledge on AMR, including the potentially competing views of different stakeholders. Findings: The framework allows key content on AMR to be selected based upon academic evidence, contextual appropriateness and fit to the chosen CE approach. A case study of the framework in action exemplifies how the framework is applicable to a range of contexts, CE approaches and One Health topics beyond just AMR. Conclusions: Within CE interventions, academic evidence is crucial to develop well-informed key content. However, this formative work should also involve community members, ensuring that their contextual knowledge is valued. The type of CE approach also needs careful consideration because methodological constraints may limit the breadth and depth of information that can be delivered within an intervention, and thus the scope of key content.

The influence of continuous renal replacement therapy on 1,3-ß-d-glucan levels in critically ill patients: a single-center retrospective propensity score study.

1,3-ß-d-Glucan (BDG) is commonly used for diagnosing invasive fungal infections (IFIs). While exposure to cellulose-based hemodialyzers is known to cause false-positive BDG results, the impact of modern hemofilters used in continuous renal replacement therapy (CRRT) remains unclear. This retrospective, single-center cohort study aimed to evaluate the effect of CRRT on BDG levels in critically ill patients. We included adult intensive care unit (ICU) patients with ≥1 BDG measurement between December 2019 and December 2020. The primary outcome was the rate of false-positive BDG results in patients exposed to CRRT compared to unexposed patients. Propensity score analysis was performed to control for confounding factors. A total of 103 ICU patients with ≥1 BDG level were identified. Most (72.8%) were medical ICU patients. Forty patients underwent CRRT using hemofilter membranes composed of sodium methallyl sulfonate copolymer (AN 69 HF) (82.5%) and of polyarylethersulfone (PAES) (17.5%). Among the 91 patients without proven IFI, 31 (34.1%) had false-positive BDG results. Univariable analysis showed an association between CRRT exposure and false-positive BDG results. However, the association between CRRT exposure and false-positive BDG results was no longer significant across three propensity score models employed: 1:1 match (n = 32) (odds ratio (OR) 1.65, p = .48), model-adjusted (n = 91) (OR 1.75, p = .38), quintile-adjusted (n = 91) (OR 1.78, p = .36). In this single-center retrospective analysis, exposure to synthetic CRRT membranes did not independently increase the risk of false-positive BDG results. Larger prospective studies are needed to further evaluate the association between CRRT exposure and false-positive BDG results in critically ill patients with suspected IFI.

Following the Birth, Life, and Death of mRNAs in Single Cells.

Recent advances in single-molecule imaging of mRNAs in fixed and living cells have enabled the lives of mRNAs to be studied with unprecedented spatial and temporal detail. These approaches have moved beyond simply being able to observe specific events and have begun to allow an understanding of how regulation is coupled between steps in the mRNA life cycle. Additionally, these methodologies are now being applied in multicellular systems and animals to provide more nuanced insights into the physiological regulation of RNA metabolism.

Co-designing community-based interventions to tackle antimicrobial resistance (AMR): what to include and why.

Antimicrobial resistance (AMR) is a social and biological problem. Although resistance to antimicrobials is a natural phenomenon, many human behaviors are increasing the pressure on microbes to develop resistance which is resulting in many commonly used treatments becoming ineffective. These behaviors include unregulated use of antimicrobial medicines, pesticides and agricultural chemicals, the disposal of heavy metals and other pollutants into the environment, and human-induced climatic change. Addressing AMR thus calls for changes in the behaviors which drive resistance. Community engagement for antimicrobial resistance (CE4AMR) is an international and interdisciplinary network focused on tackling behavioural drivers of AMR at community level. Since 2019 this network has worked within Low-Middle Income Countries (LMICs), predominantly within Southeast Asia, to tackle behavioral drivers of AMR can be mitigated through bottom-up solutions championed by local people. This commentary presents seven Key Concepts identified from across the CE4AMR portfolio as integral to tackling AMR. We suggest it be used to guide future interventions aimed at addressing AMR via social, participatory, and behavior-change approaches.

Dopaminergic systems create reward seeking despite adverse consequences.

Resource-seeking behaviours are ordinarily constrained by physiological needs and threats of danger, and the loss of these controls is associated with pathological reward seeking1. Although dysfunction of the dopaminergic valuation system of the brain is known to contribute towards unconstrained reward seeking2,3, the underlying reasons for this behaviour are unclear. Here we describe dopaminergic neural mechanisms that produce reward seeking despite adverse consequences in Drosophila melanogaster. Odours paired with optogenetic activation of a defined subset of reward-encoding dopaminergic neurons become cues that starved flies seek while neglecting food and enduring electric shock punishment. Unconstrained seeking of reward is not observed after learning with sugar or synthetic engagement of other dopaminergic neuron populations. Antagonism between reward-encoding and punishment-encoding dopaminergic neurons accounts for the perseverance of reward seeking despite punishment, whereas synthetic engagement of the reward-encoding dopaminergic neurons also impairs the ordinary need-dependent dopaminergic valuation of available food. Connectome analyses reveal that the population of reward-encoding dopaminergic neurons receives highly heterogeneous input, consistent with parallel representation of diverse rewards, and recordings demonstrate state-specific gating and satiety-related signals. We propose that a similar dopaminergic valuation system dysfunction is likely to contribute to maladaptive seeking of rewards by mammals.

Antimicrobial resistance (AMR) as a form of human-wildlife conflict: Why and how nondomesticated species should be incorporated into AMR guidance.

The challenge of antimicrobial resistance (AMR) continues to receive significant global attention as common infections become increasingly resistant to the drugs used to treat them. Once an infectious microbe has developed a mechanism of resistance, it can cause longer, more damaging infections which are more costly, time-consuming, and sometimes impossible to treat. Such impacts occur across the health of humans, animals, plants, and the environment. Thus, AMR is considered a One Health issue. However, current narratives on AMR focus on humans, food-producing animals, crops, and their immediate environments. Very little attention is given to wildlife in terms of the impact of AMR on their health, nor their role in the evolution and spread of AMR. This article (1) discusses an absence of wildlife in current AMR guidance, (2) suggests how this absence of wildlife could limit understanding of, and action on, AMR, (3) proposes that considering AMR as a form of human-wildlife conflict could enable AMR guidance to better incorporate wildlife into action planning and create a truly One Health approach to tackle AMR.

Sleep duration change among adolescents in Canada: Examining the impact of COVID-19 in worsening inequity.

Purpose: The purpose of this study was to assess if adolescent sub-populations in Canada (i.e., based on race/ethnicity, sex/gender, socioeconomic status, and urbanicity groups) experienced a larger change in sleep duration and guideline adherence between 2019 and 2020 (pre-pandemic) and the 2020-2021 (mid-pandemic) school years. Methods: Longitudinally linked data from 2019 to 2020 (pre-pandemic) and 2020-2021 (mid-pandemic) of a prospective cohort study of secondary school students (M = 14.2, SD = 1.3 years, N = 8209) in Canada were used for analyses. Regression modelling tested the main effects of race/ethnicity, sex/gender, socioeconomic status, and urbanicity on changes in sleep duration as well as adherence to Canada's 24-h Movement Guidelines for sleep (8-10 h/night). Interactions between identity variables (race/ethnicity or sex/gender) and other main effect variables were subsequently tested. Results: Females gained more sleep (4.5 [1.5, 7.5] min/day more) and increased guideline adherence (AOR = 1.16 [1.04, 1.30] than males on average. Asian race/ethnic identity was associated with less sleep gain than White identity -10.1 [-19.4, -0.8], but not guideline adherence. Individuals in large urban areas gained less sleep and adhered less to guidelines than individuals from any other level of urbanicity (-21.4 [-38.5, -4.2] to -15.5 [-30.7, -0.2] min/day). Higher individual SES scores were associated with greater sleep gain (linear trend: 11.16 [1.2-21.1]). The discrepancies in sleep gain and guideline adherence between males and females were significantly modified by race/ethnicity and urbanicity. Discussion: Increases in sleep duration may be one of the few benefits to adolescents during the COVID-19 pandemic but were not equally distributed across sub-populations. Efforts to promote better sleep adherence may need to account for sex/gender differences, especially in less urbanized areas and certain racial/ethnic groups.

Rapid implementation of an emergency on-site CKRT dialysate production system during the COVID-19 pandemic.

BACKGROUND: On December 29, 2021, during the delta wave of the Coronavirus Disease 2019 (COVID-19) pandemic, the stock of premanufactured solutions used for continuous kidney replacement therapy (CKRT) at the University of New Mexico Hospital (UNMH) was nearly exhausted with no resupply anticipated due to supply chain disruptions. Within hours, a backup plan, devised and tested 18 months prior, to locally produce CKRT dialysate was implemented. This report describes the emergency implementation and outcomes of this on-site CKRT dialysate production system. METHODS: This is a single-center retrospective case series and narrative report describing and reporting the outcomes of the implementation of an on-site CKRT dialysate production system. All adults treated with locally produced CKRT dialysate in December 2021 and January 2022 at UNMH were included. CKRT dialysate was produced locally using intermittent hemodialysis machines, hemodialysis concentrate, sterile parenteral nutrition bags, and connectors made of 3-D printed biocompatible rigid material. Outcomes analyzed included dialysate testing for composition and microbiologic contamination, CKRT prescription components, patient mortality, sequential organ failure assessment (SOFA) scores, and catheter-associated bloodstream infections (CLABSIs). RESULTS: Over 13 days, 22 patients were treated with 3,645 L of locally produced dialysate with a mean dose of 20.0 mL/kg/h. Fluid sample testing at 48 h revealed appropriate electrolyte composition and endotoxin levels and bacterial colony counts at or below the lower limit of detection. No CLABSIs occurred within 7 days of exposure to locally produced dialysate. In-hospital mortality was 81.8% and 28-day mortality was 68.2%, though illness severity was high, with a mean SOFA score of 14.5. CONCLUSIONS: Though producing CKRT fluid with IHD machines is not novel, this report represents the first description of the rapid and successful implementation of a backup plan for local CKRT dialysate production at a large academic medical center in the U.S. during the COVID-19 pandemic. Though conclusions are limited by the retrospective design and limited sample size of our analysis, our experience could serve as a guide for other centers navigating similar severe supply constraints in the future.

Completion of Genetic Testing and Incidence of Pathogenic Germline Mutation among Patients with Early-Onset Colorectal Cancer: A Single Institution Analysis.

Over the past 20 years, rates of early-onset colorectal cancer (eoCRC), defined as <50 years of age at diagnosis, have increased, with 16-25% associated with a pathogenic germline variant (PGV) resulting in a hereditary cancer syndrome. In the present study, we sought to further characterize PGVs observed in patients with eoCRC. We conducted a retrospective analysis of patients with a history of CRC referred for genetic counseling at Mayo Clinic Rochester between April 2019 and April 2022. Three hundred and three CRC patients were referred to medical genetics, including 124 with a history of eoCRC. Only 84 patients (68%) with eoCRC referred for genetic counseling completed genetic testing, with an average of 48 genes evaluated. PGVs were identified in 27.4% with eoCRC, including 8.3% with Lynch syndrome (LS). Other detected PGVs known to increase the risk of CRC included MUTYH (4.8%), CHEK2 (3.6%), APC, BMPR1A, and TP53 (1.3% each). Among those with aoCRC, 109 patients (61%) completed genetic testing, among which 88% had either a dMMR tumor, personal history of an additional LS malignancy, or family history of LS malignancy, with PGVs detected in 23% of patients. This study reinforces the importance for all patients with CRC, especially those with eoCRC, to undergo germline testing.