Information theory reveals physiological manifestations of COVID-19 that correlate with symptom density of illness.

Algorithms for the detection of COVID-19 illness from wearable sensor devices tend to implicitly treat the disease as causing a stereotyped (and therefore recognizable) deviation from healthy physiology. In contrast, a substantial diversity of bodily responses to SARS-CoV-2 infection have been reported in the clinical milieu. This raises the question of how to characterize the diversity of illness manifestations, and whether such characterization could reveal meaningful relationships across different illness manifestations. Here, we present a framework motivated by information theory to generate quantified maps of illness presentation, which we term "manifestations," as resolved by continuous physiological data from a wearable device (Oura Ring). We test this framework on five physiological data streams (heart rate, heart rate variability, respiratory rate, metabolic activity, and sleep temperature) assessed at the time of reported illness onset in a previously reported COVID-19-positive cohort (N = 73). We find that the number of distinct manifestations are few in this cohort, compared to the space of all possible manifestations. In addition, manifestation frequency correlates with the rough number of symptoms reported by a given individual, over a several-day period prior to their imputed onset of illness. These findings suggest that information-theoretic approaches can be used to sort COVID-19 illness manifestations into types with real-world value. This proof of concept supports the use of information-theoretic approaches to map illness manifestations from continuous physiological data. Such approaches could likely inform algorithm design and real-time treatment decisions if developed on large, diverse samples.

Thermochemical Properties of High Pressure Neodymium Monoxide.

Neodymium monoxide (NdO) is a metastable rare earth oxide material with a unique electronic structure, which has potential applications across various fields such as semiconductors, energy, catalysis, laser technology, and advanced communications. Despite its promising attributes, the thermodynamic properties of NdO remain unexplored. In this study, high pressure, high temperature phases of neodymium monoxide (NdO, with a rocksalt structure) and body-centered cubic (bcc) Nd metal were synthesized at 5 GPa and 1473 K. X-ray photoelectron spectroscopy (XPS) measurements indicate that the Nd 3d peak shifts to higher energy in NdO relative to Nd2O3, suggesting the possibility of complex electronic states in NdO. Formation enthalpies for the reaction 1/3Nd2O3 + 1/3bcc Nd = NdO obtained from high temperature solution calorimetry in molten sodium molybdate and for the reaction dhcp Nd (metal) = bcc Nd (metal) from differential scanning calorimetry are 25.98 ± 8.65 and 5.2 kJ/mol, respectively. Utilizing these enthalpy values, we calculated the pressure-temperature boundary for the reaction 1/3 bcc Nd + 1/3Nd2O3 = NdO, which has a negative P-T slope of -1.68× 10-4 GPa/K. These insights reveal the high pressure behavior of NdO and neodymium metal, underscoring their potential utility in technological applications.

Blockade of IL-1ß and PD-1 with combination chemotherapy reduces systemic myeloid suppression in metastatic pancreatic cancer with heterogeneous effects in the tumor.

Innate inflammation promotes tumor development, although the role of innate inflammatory cytokines in established human tumors is unclear. Here we report clinical and translational results from a phase Ib trial testing whether IL-1ß blockade in human pancreatic cancer would alleviate myeloid immunosuppression and reveal antitumor T-cell responses to PD-1 blockade. Patients with treatment-naïve advanced pancreatic ductal adenocarcinoma (n=10) were treated with canakinumab, a high-affinity monoclonal human anti-interleukin-1ß (IL-1ß), the PD-1 blocking antibody spartalizumab, and gemcitabine/n(ab)paclitaxel. Analysis of paired peripheral blood from patients in the trial versus patients receiving multiagent chemotherapy showed a modest increase in HLA-DR+CD38+ activated CD8+ T cells and a decrease in circulating monocytic myeloid-derived suppressor cells (MDSCs) by flow cytometry for patients in the trial, but not in controls. Similarly, we used patient serum to differentiate monocytic MDSCs in vitro and showed that functional inhibition of T-cell proliferation was reduced when using on-treatment serum samples from patients in the trial but not when using serum from patients treated with chemotherapy alone. Within the tumor we observed few changes in suppressive myeloid-cell populations or activated T cells as assessed by single-cell transcriptional profiling or multiplex immunofluorescence, although increases in CD8+ T cells suggest that improvements in the tumor immune microenvironment might be revealed by a larger study. Overall, the data indicate that exposure to PD-1 and IL-1ß blockade induced a modest reactivation of peripheral CD8+ T cells and decreased circulating monocytic MDSCs; however, these changes did not lead to similarly uniform alterations in the tumor microenvironment.

Benzene-1,2,4,5-tetrol.

The crystal structure of the title compound was determined at 120 K. It crystallizes in the triclinic space group P with four independent mol-ecules in the asymmetric unit. In the crystal, each symmetry-unique mol-ecule forms π-π stacks on itself, giving four unique π-π stacking inter-actions. Inter-molecular hydrogen bonding is observed between each pair of independent mol-ecules, where each hy-droxy group can act as a hydrogen-bond donor and acceptor.

Biomechanical evaluation of porcine lens capsule with and without nucleus after capsulotomy - Finite element analysis.

Previous studies have shown that the nucleus could offer structural support to the lens capsule. This study investigated the biomechanical performance of porcine lens with and without nucleus for 4 mm, 4.5 mm, 5 mm, 5.5 mm and 6 mm capsulotomy and its potential impact on the stretch ratio of capsular bag when the anterior capsulotomy edge was stretched. Our simulation results showed higher strain for the capsular bag with nucleus, which is crucial for the porcine lens to tolerate more stretch without failure. This simulation could support future study on the optimization of capsulotomy based on patient specific condition, that is, the geometry of lens.

Parental beliefs, attitudes, and practices on nutrition and children feeding: implications to preventive measures on children's obesity in Saudi Arabia.

OBJECTIVE: Parents have a profound influence on their children's dietary habits. Parents' perspectives, attitudes, and behaviors regarding feeding their children a nutritious diet can have a significant impact on their children's health. The objective of this study was to examine the attitudes, beliefs, and feeding practices of parents in relation to nutrition for their children and to determine how these factors influence strategies for preventing obesity. SUBJECTS AND METHODS: A total of 446 Saudi mothers with children aged 2-12 years were recruited for this study. The Child Feeding Questionnaire (CFQ) was administered to mothers via an instant messaging application. RESULTS: Mothers' age showed a significant difference in perceived responsibility (p < 0.004), perceived parental weight (p = 0.000), perceived child's weight (p = 0.000), and concern about the child's weight (p = 0.000). Mothers with postgraduate degrees exhibited a significant difference in perceived child weight (p < 0.003); occupational status showed a significant difference in perceived parental weight (p < 0.004), perceived child weight (p < 0.001), and residence, particularly in Riyadh, which showed a significant difference in perceived parental weight (p < 0.026). There were also significant differences in body mass index (BMI) (p = 0.000) and perceived parental weight in relation to the mother's age. Mothers' age was significantly related to food restrictions (p = 0.000), pressure to eat (p = 0.000), and monitoring (p < 0.009). Mothers with only one child displayed significance in relation to pressure to eat (p < 0.019), while government-employee mothers showed a significant relationship with food restrictions (p < 0.005). There was a noteworthy association between the age of the mothers and perceived responsibility (p < 0.001), occupation (p < 0.22), residence (p = 0.000), and the mother's BMI (p = 0.000) with perceived parental weight. Finally, occupation (p < 0.006) was found to significantly influence food restriction, while the mother's age was significantly related to the pressure to eat (p < 0.002). CONCLUSIONS: Parental attitudes, practices, and beliefs regarding child feeding were strongly associated with maternal age, occupation, and BMI. Targeted interventions should be developed to assist mothers exhibiting these characteristics in establishing healthier and more effective feeding routines for their children. For example, interventions could be designed to educate parents on the latest findings regarding child-feeding habits and help them develop a greater sense of responsibility for their children's nutrition.

Artificial intelligence chatbot vs pathology faculty and residents: Real-world clinical questions from a genitourinary treatment planning conference.

OBJECTIVES: Artificial intelligence (AI)-based chatbots have demonstrated accuracy in a variety of fields, including medicine, but research has yet to substantiate their accuracy and clinical relevance. We evaluated an AI chatbot's answers to questions posed during a treatment planning conference. METHODS: Pathology residents, pathology faculty, and an AI chatbot (OpenAI ChatGPT [January 30, 2023, release]) answered a questionnaire curated from a genitourinary subspecialty treatment planning conference. Results were evaluated by 2 blinded adjudicators: a clinician expert and a pathology expert. Scores were based on accuracy and clinical relevance. RESULTS: Overall, faculty scored highest (4.75), followed by the AI chatbot (4.10), research-prepared residents (3.50), and unprepared residents (2.87). The AI chatbot scored statistically significantly better than unprepared residents (P = .03) but not statistically significantly different from research-prepared residents (P = .33) or faculty (P = .30). Residents did not statistically significantly improve after research (P = .39), and faculty performed statistically significantly better than both resident categories (unprepared, P < .01; research prepared, P = .01). CONCLUSIONS: The AI chatbot gave answers to medical questions that were comparable in accuracy and clinical relevance to pathology faculty, suggesting promise for further development. Serious concerns remain, however, that without the ability to provide support with references, AI will face legitimate scrutiny as to how it can be integrated into medical decision-making.

Interruption of the intratumor CD8+ T cell:Treg crosstalk improves the efficacy of PD-1 immunotherapy.

PD-1 blockade unleashes potent antitumor activity in CD8+ T cells but can also promote immunosuppressive T regulatory (Treg) cells, which may worsen the response to immunotherapy. Tumor-Treg inhibition is a promising strategy to improve the efficacy of checkpoint blockade immunotherapy; however, our understanding of the mechanisms supporting tumor-Tregs during PD-1 immunotherapy is incomplete. Here, we show that PD-1 blockade increases tumor-Tregs in mouse models of melanoma and metastatic melanoma patients. Mechanistically, Treg accumulation is not caused by Treg-intrinsic inhibition of PD-1 signaling but depends on an indirect effect of activated CD8+ T cells. CD8+ T cells produce IL-2 and colocalize with Tregs in mouse and human melanomas. IL-2 upregulates the anti-apoptotic protein ICOS on tumor-Tregs, promoting their accumulation. Inhibition of ICOS signaling before PD-1 immunotherapy improves control over immunogenic melanoma. Thus, interrupting the intratumor CD8+ T cell:Treg crosstalk represents a strategy to enhance the therapeutic efficacy of PD-1 immunotherapy.

Association of Medical School Gap Year Research and Degree Programs With Otolaryngology Interview and Match Outcomes.

OBJECTIVE: To investigate whether a gap year for either research or a master's degree is associated with interview offers or match outcomes among otolaryngology applicants. METHODS: Using the Texas Seeking Transparency in Application to Residency (Texas STAR) database, we conducted a cross-sectional analysis of otolaryngology applicants from 2018 to 2022. Applicants were stratified based on the presence and type of gap year during medical school. Applicant characteristics, signaling, research productivity, and application costs were analyzed, with primary outcomes including number of interview offers and match status. RESULTS: Among 564 otolaryngology applicant respondents to the Texas STAR survey, 160 (28%) reported a gap year, including 64 (40%) applicants participating in a research year, 65 (41%) completing a Master of Public Health or Science (MPH and MSc), and 31 (19%) completing a Master of Business Administration, Education, or other degree (MBA and MEd). Gap-year applicants who completed a research year or MPH/MSc degree received more interview offers (P < .01) than MBA, MEd applicants, or those without a gap year. Applicants with a research year had the most publications, oral presentations, abstracts, posters, and research experiences (all P < .01). When controlling for USMLE scores, clerkship honors, and applications submitted, applicants completing a research year or an MPH/MSc-degree received increased interview offers (P < .01). No significant differences were seen in expenditures or match rates. CONCLUSIONS: Research and MPH/MSc gap years were associated with increased residency interview offers but not increased match success. Further longitudinal studies are needed to assess how yearlong experiences affect long-term career outcomes.

Treatment Patterns and Outcomes by Age in Metastatic Urinary Tract Cancer: A Retrospective Tertiary Cancer Center Analysis.

Metastatic urinary tract cancer (mUTC) is challenging to treat in older adults due to comorbidities. We compared the clinical courses of younger and older (≥70 years) adults with mUTC receiving first-line (1L) systemic therapy in a tertiary cancer center. Baseline clinical characteristics, treatments received, tolerability, and survival outcomes were analyzed. Among 212 patients (103 older vs. 109 younger), the older patients had lower hemoglobin at baseline (84% vs. 71%, p = 0.03), the majority were cisplatin-ineligible (74% vs. 45%, p < 0.001), received more immunotherapy-based treatments in the 1L (52% vs. 36%, p = 0.01), received fewer subsequent lines of treatment (median 0 vs. 1, p = 0.003), and had lower clinical trial participation (30% vs. 18%, p = 0.05) compared to the younger patients. When treated with 1L chemotherapy, older patients required more dose adjustments (53.4% vs. 23%, p = 0.001) and received fewer cycles of chemotherapy (median 4 vs. 5, p= 0.01). Older patients had similar OS (11.2 months vs. 14 months, p = 0.06) and similar rates of treatment-related severe toxicity and healthcare visits, independent of the type of systemic treatment received, compared to younger patients. We conclude that select older adults with mUTC can be safely treated with immunotherapy and risk-adjusted regimens of chemotherapy with tangible survival benefits.

Oral HIF-2α Inhibitor Belzutifan in Ocular von Hippel-Lindau Disease: Subgroup Analysis of the Single-Arm Phase 2 LITESPARK-004 Study.

OBJECTIVE: To report the efficacy of oral HIF-2α inhibitor belzutifan in participants with von Hippel-Lindau disease-associated retinal hemangioblastomas in LITESPARK-004. DESIGN: Subgroup analysis of the phase 2, single-arm, open-label LITESPARK-004 study. PARTICIPANTS: Adults with ≥1 von Hippel-Lindau disease-associated measurable renal cell carcinoma tumor not requiring immediate surgical intervention were eligible. METHODS AND INTERVENTION: Participants received oral belzutifan 120 mg once daily until disease progression or unacceptable treatment-related toxicity. MAIN OUTCOME MEASURES: Efficacy of belzutifan in retinal hemangioblastomas was a secondary end point, measured as response (improved, stable, or progressed) by independent reading center certified graders based on color fundus imaging performed every 12 weeks using the investigator's preferred imaging standards. Additional assessments, where available, included optical coherence tomography and ultra-widefield fluorescein angiography. RESULTS: Among 61 participants in LITESPARK-004, 12 had ≥1 evaluable active retinal hemangioblastoma in 16 eyes at baseline per independent reading center. As of April 1, 2022, the median follow-up for participants with ocular von Hippel-Lindau disease at baseline was 37.3 months. All 16 eyes were graded as improved, with a response rate of 100.0% (95% confidence intervals, 79.4-100.0). No new retinal hemangioblastomas or ocular disease progression were reported as of data cutoff date. Eight participants had additional multimodal eye assessments performed at the National Institutes of Health study site. Among this subgroup, 10 of 24 hemangioblastomas in 8 eyes of 6 participants measured ≥500 µm in greatest linear dimension at baseline and were further analyzed. All 10 hemangioblastomas had a mean area reduction of ≥15% by month 12 and ≥30% by month 24. CONCLUSIONS: Belzutifan showed promising activity against ocular von Hippel-Lindau disease, including capacity to control retinal hemangioblastomas, with effects sustained for >2 years while on treatment.

Diagnosis of Inflammatory Bowel Disease-Associated Peripheral Arthritis: A Systematic Review.

BACKGROUND: Inflammatory bowel disease (IBD)-associated peripheral spondyloarthritis (pSpA) decreases quality of life and remains poorly understood. Given the prevalence of this condition and its negative impact, it is surprising that evidence-based disease definitions and diagnostic strategies are lacking. This systematic review summarizes available data to facilitate development and validation of diagnostics, patient-reported outcomes, and imaging indices specific to this condition. METHODS: A literature search was conducted. Consensus or classification criteria, case series, cross-sectional studies, cohort studies, and randomized controlled trials related to diagnosis were included. RESULTS: A total of 44 studies reporting data on approximately 1500 patients with pSpA were eligible for analysis. Data quality across studies was only graded as fair to good. Due to large heterogeneity, meta-analysis was not possible. The majority of studies incorporated patient-reported outcomes and a physical examination. A total of 13 studies proposed or validated screening tools, consensus, classification, or consensus criteria. A total of 28 studies assessed the role of laboratory tests, none of which were considered sufficiently accurate for use in diagnosis. A total of 17 studies assessed the role of imaging, with the available literature insufficient to fully endorse any imaging modality as a robust diagnostic tool. CONCLUSIONS: This review highlights existing inconsistency and lack of a clear diagnostic approach for IBD-associated pSpA. Given the absence of an evidence-based approach, a combination of existing criteria and physician assessment should be utilized. To address this issue comprehensively, our future efforts will be directed toward pursuit of a multidisciplinary approach aimed at standardizing evaluation and diagnosis of IBD-associated pSpA.

This systematic review highlights the lack of an evidence-based approach to the diagnosis of inflammatory bowel disease­associated peripheral spondyloarthritis and the need to standardize evaluation and diagnosis via multidisciplinary collaboration with development of patient-reported outcomes and imaging indices.

A Propensity Score-Matched Analysis of Single-Port vs. Multi-Port Laparoscopic Total Abdominal Colectomy with End Ileostomy for Medically Refractory Ulcerative Colitis.

BACKGROUND: Medically refractory ulcerative colitis (UC) necessitates surgical intervention, with total abdominal colectomy with end ileostomy being a definitive treatment. The comparison between single-port and multi-port laparoscopic surgery outcomes remains underexplored. OBJECTIVE: To compare the surgical outcomes of single-port versus multi-port laparoscopic surgery in patients undergoing total abdominal colectomy with end ileostomy for medically refractory UC. DESIGN: A retrospective analysis comparing single-port to multi-port surgery in UC patients from 2010 to 2020. Patients were propensity score-matched 3:1 (multi-port to single-port) on baseline characteristics. SETTINGS: Single center academic hospital. MAIN OUTCOME MEASURES: Binary outcomes were compared using a multivariable logistic regression model, and a subset analysis was conducted for postoperative stump leak based on stump implantation during surgery. These metrics were compared between the single-port and multi-port groups to assess the differences in surgical outcomes. RESULTS: The multi-port and single-port groups included 642 and 114 patients, respectively. Matched cohort included 342 multi-ports and 114 single-ports. We observed a statistically significant difference in mean operation time, with the single-port procedure taking 43 minutes less than the multi-port laparoscopy. There were no significant differences between the two groups in postoperative stump leaks, postoperative ileus, stoma site complications, postoperative readmission within 30 days, postoperative reoperation within 30 days, and subsequent IPAA surgery. In the subset analysis, stump implantation was associated with a higher risk of stump leak in the multiport group. The single-port group had a shorter hospital stay. LIMITATIONS: Retrospective nature, being conducted at a single center. CONCLUSION: Single-incision laparoscopic total abdominal colectomy in the treatment of mucosal ulcerative colitis is a safe, effective, and efficient approach. In our cohort, as compared to multi-port approach, single incision laparoscopy has shown shorter operation times and better overall length of stay. Taking into account less invasive approach, decreased abdominal trauma, and faster recovery, single-port surgery is a viable alternative to multi-port surgery. See Video Abstract.

Prevalence of micronutrient deficiencies across diverse environments in rural Madagascar.

It is estimated that billions of people around the world are affected by micronutrient deficiencies. Madagascar is considered to be particularly nutritionally vulnerable, with nearly half of the population stunted, and parts of the country facing emergency, near famine-like conditions (IPC4). Although Madagascar is generally considered among the most undernourished of countries, empirical data in the form of biological samples to validate these claims are extremely limited. Our research drew data from three studies conducted between 2013-2020 and provided comprehensive biomarker profile information for 4,710 individuals from 30 communities in five different ecological regions during at least one time-point. Estimated prevalences of nutrient deficiencies and inflammation across various regions of rural Madagascar were of concern for both sexes and across all ages, with 66.5% of the population estimated to be deficient in zinc, 15.6% depleted in vitamin B12 (3.6% deficient), 11.6% deficient in retinol, and lower levels of iron deficiency (as indicated by 11.7% deficient in ferritin and 2.3% deficient assessed by soluble transferrin receptors). Beyond nutrient status biomarkers, nearly one quarter of the population (24.0%) exhibited chronic inflammation based on high values of α-1-acid glycoprotein, and 12.3% exhibited acute inflammation based on high values of C-reactive protein. There is an 8-fold difference between the lowest and highest regional observed prevalence of vitamin B12 deficiency, a 10-fold difference in vitamin A deficiency (based on retinol), and a 2-fold difference in acute inflammation (CRP) and deficiencies of zinc and iron (based on ferritin), highlighting strong geographical variations in micronutrient deficiencies across Madagascar.

Natural variation in protein kinase D modifies alcohol sensitivity in Caenorhabditis elegans.

Differences in naïve alcohol sensitivity between individuals are a strong predictor of later life alcohol use disorders (AUD). However, the genetic bases for alcohol sensitivity (beyond ethanol metabolism) and pharmacological approaches to modulate alcohol sensitivity remain poorly understood. We used a high-throughput behavioral screen to measure acute behavioral sensitivity to alcohol, a model of intoxication, in a genetically diverse set of over 150 wild strains of the nematode Caenorhabditis elegans. We performed a genome-wide association study to identify loci that underlie natural variation in alcohol sensitivity. We identified five quantitative trait loci (QTL) and further show that variants in the C. elegans ortholog of protein kinase D, dkf-2, likely underlie the chromosome V QTL. We found that resistance to intoxication was conferred by dkf-2 loss-of-function mutations as well as partly by a PKD inhibitor in a dkf-2-dependent manner. Protein kinase D might represent a conserved, druggable target to modify alcohol sensitivity with application towards AUD.

Five million nights: temporal dynamics in human sleep phenotypes.

Sleep monitoring has become widespread with the rise of affordable wearable devices. However, converting sleep data into actionable change remains challenging as diverse factors can cause combinations of sleep parameters to differ both between people and within people over time. Researchers have attempted to combine sleep parameters to improve detecting similarities between nights of sleep. The cluster of similar combinations of sleep parameters from a night of sleep defines that night's sleep phenotype. To date, quantitative models of sleep phenotype made from data collected from large populations have used cross-sectional data, which preclude longitudinal analyses that could better quantify differences within individuals over time. In analyses reported here, we used five million nights of wearable sleep data to test (a) whether an individual's sleep phenotype changes over time and (b) whether these changes elucidate new information about acute periods of illness (e.g., flu, fever, COVID-19). We found evidence for 13 sleep phenotypes associated with sleep quality and that individuals transition between these phenotypes over time. Patterns of transitions significantly differ (i) between individuals (with vs. without a chronic health condition; chi-square test; p-value < 1e-100) and (ii) within individuals over time (before vs. during an acute condition; Chi-Square test; p-value < 1e-100). Finally, we found that the patterns of transitions carried more information about chronic and acute health conditions than did phenotype membership alone (longitudinal analyses yielded 2-10× as much information as cross-sectional analyses). These results support the use of temporal dynamics in the future development of longitudinal sleep analyses.

Electron-Activated Dissociation and Collision-Induced Dissociation Glycopeptide Fragmentation for Improved Glycoproteomics.

Tandem mass spectrometry coupled with liquid chromatography (LC-MS/MS) has proven a versatile tool for the identification and quantification of proteins and their post-translational modifications (PTMs). Protein glycosylation is a critical PTM for the stability and biological function of many proteins, but full characterization of site-specific glycosylation of proteins remains analytically challenging. Collision-induced dissociation (CID) is the most common fragmentation method used in LC-MS/MS workflows, but the loss of labile modifications renders CID inappropriate for detailed characterization of site-specific glycosylation. Electron-based dissociation methods provide alternatives that retain intact glycopeptide fragments for unambiguous site localization, but these methods often underperform CID due to increased reaction times and reduced efficiency. Electron-activated dissociation (EAD) is another strategy for glycopeptide fragmentation. Here, we use a ZenoTOF 7600 SCIEX instrument to compare the performance of various fragmentation techniques for the analysis of a complex mixture of mammalian O- and N-glycopeptides. We found CID fragmentation identified the most glycopeptides and generally produced higher quality spectra, but EAD provided improved confidence in glycosylation site localization. Supplementing EAD with CID fragmentation (EAciD) further increased the number and quality of glycopeptide identifications, while retaining localization confidence. These methods will be useful for glycoproteomics workflows for either optimal glycopeptide identification or characterization.

Perianal Fistulizing Crohn's Disease-Associated Anorectal and Fistula Cancers: Systematic Review and Expert Consensus.

BACKGROUND & AIMS: Perianal fistulizing Crohn's disease (PFCD)-associated anorectal and fistula cancers are rare but often devastating diagnoses. However, given the low incidence and consequent lack of data and clinical trials in the field, there is little to no guidance on screening and management of these cancers. To inform clinical practice, we developed consensus guidelines on PFCD-associated anorectal and fistula cancers by multidisciplinary experts from the international TOpClass consortium. METHODS: We conducted a systematic review by standard methodology, using the Newcastle-Ottawa Scale quality assessment tool. We subsequently developed consensus statements using a Delphi consensus approach. RESULTS: Of 561 articles identified, 110 were eligible, and 76 articles were included. The overall quality of evidence was low. The TOpClass consortium reached consensus on 6 structured statements addressing screening, risk assessment, and management of PFCD-associated anorectal and fistula cancers. Patients with long-standing (>10 years) PFCD should be considered at small but increased risk of developing perianal cancer, including squamous cell carcinoma of the anus and anorectal carcinoma. Risk factors for squamous cell carcinoma of the anus, notably human papilloma virus, should be considered. New, refractory, or progressive perianal symptoms should prompt evaluation for fistula cancer. There was no consensus on timing or frequency of screening in patients with asymptomatic perianal fistula. Multiple modalities may be required for diagnosis, including an examination under anesthesia with biopsy. Multidisciplinary team efforts were deemed central to the management of fistula cancers. CONCLUSIONS: Inflammatory bowel disease clinicians should be aware of the risk of PFCD-associated anorectal and fistula cancers in all patients with PFCD. The TOpClass consortium consensus statements outlined herein offer guidance in managing this challenging scenario.