Interfaces of Malignant and Immunologic Clonal Dynamics in Ovarian Cancer.

High-grade serous ovarian cancer (HGSC) exhibits extensive malignant clonal diversity with widespread but non-random patterns of disease dissemination. We investigated whether local immune microenvironment factors shape tumor progression properties at the interface of tumor-infiltrating lymphocytes (TILs) and cancer cells. Through multi-region study of 212 samples from 38 patients with whole-genome sequencing, immunohistochemistry, histologic image analysis, gene expression profiling, and T and B cell receptor sequencing, we identified three immunologic subtypes across samples and extensive within-patient diversity. Epithelial CD8+ TILs negatively associated with malignant diversity, reflecting immunological pruning of tumor clones inferred by neoantigen depletion, HLA I loss of heterozygosity, and spatial tracking between T cell and tumor clones. In addition, combinatorial prognostic effects of mutational processes and immune properties were observed, illuminating how specific genomic aberration types associate with immune response and impact survival. We conclude that within-patient spatial immune microenvironment variation shapes intraperitoneal malignant spread, provoking new evolutionary perspectives on HGSC clonal dispersion.

Effects of neoadjuvant radiochemotherapy for anorectal function in locally advanced rectal cancer patients: a study protocol for a prospective, observational, controlled, multicentre study.

BACKGROUND: Neoadjuvant chemoradiotherapy (NCRT) and total mesorectal excision are standard treatment regimen for patients with locally advanced rectal cancer (LARC). This sphincter-saving treatment strategy may be accompanied by a series of anorectal functional disorders. Yet, prospective studies that dynamically evaluating the respective roles of radiotherapy, chemotherapy and surgery on anorectal function are lacking. PATIENTS/DESIGN: The study is a prospective, observational, controlled, multicentre study. After screening for eligibility and obtaining informed consent, a total of 402 LARC patients undergoing NCRT followed by surgery, or neoadjuvant chemotherapy followed by surgery, or surgery only would be included in the trial. The primary outcome measure is the average resting pressure of anal sphincter. The secondary outcome measures are maximum anal sphincter contraction pressure, Wexner continence score and low anterior resection syndrome (LARS) score. Evaluations will be carried out at the following stages: baseline (T1), after radiotherapy or chemotherapy (before surgery, T2), after surgery (before closing the temporary stoma, T3), and at follow-up visits (every 3 to 6 months, T4, T5……). Follow-up for each patient will be at least 2 years. DISCUSSION: We expect the program to provide more information of neoadjuvant radiotherapy and/or chemotherapy on anorectal function, and to optimize the treatment strategy to reduce anorectal dysfunction for LARC patients. TRIAL REGISTRATION: ClinicalTrials.gov (NCT05671809). Registered on 26 December 2022.

Integrated structural variation and point mutation signatures in cancer genomes using correlated topic models.

Mutation signatures in cancer genomes reflect endogenous and exogenous mutational processes, offering insights into tumour etiology, features for prognostic and biologic stratification and vulnerabilities to be exploited therapeutically. We present a novel machine learning formalism for improved signature inference, based on multi-modal correlated topic models (MMCTM) which can at once infer signatures from both single nucleotide and structural variation counts derived from cancer genome sequencing data. We exemplify the utility of our approach on two hormone driven, DNA repair deficient cancers: breast and ovary (n = 755 samples total). We show how introducing correlated structure both within and between modes of mutation can increase accuracy of signature discovery, particularly in the context of sparse data. Our study emphasizes the importance of integrating multiple mutation modes for signature discovery and patient stratification, and provides a statistical modeling framework to incorporate additional features of interest for future studies.

Correction: TERT promoter mutation in adult granulosa cell tumor of the ovary.

The original version of this Article omitted the author Hannah van Meurs from the Department of Gynecology, Center for Gynecologic Oncology Amsterdam, Academic Medical Center, 1100 DD Amsterdam, The Netherlands. This has been corrected in both the PDF and HTML versions of the article.

Prognostic value of estrogen receptor-α and progesterone receptor in curatively resected colorectal cancer: a retrospective analysis with independent validations.

BACKGROUND: Prognostic assessment is crucial for optimal treatment. The aim of our study was to investigate the potential impact of estrogen receptor-α (ER-α) and progesterone receptor (PR) on the prognosis of colorectal cancer (CRC) patients who received curative resection. METHODS: Retrospective evaluation of two independent cohorts of CRC patients maintained prospectively in 2009-2010 (training set) (n = 148) and 2007-2009 (internal validation set) (n = 485). Furthermore, we used an external independent CRC cohort from The Cancer Genome Atlas (TCGA) (n = 511) for further validation. ER-α and PR expression as well as other potential prognostic factors were retrospectively evaluated in training set with respect to overall survival (OS), local relapse free survival (LRFS) and distant metastasis free survival (DMFS). The prognostic factors found in training set will be validated in two validation cohorts. RESULTS: On univariate analysis for the training set, OS, LRFS and DMFS were not associated with PR expression. While patients with ER-αexpression were found to have poor prognosis. In addition, multivariate analysis showed that ER-αexpression maintained significance with respect to OS (HR, 5.06; p = 0.002), LRFS (HR, 8.81; p = 0.002) and DMFS (HR, 8.07; p = 0.004). Similarly, ER-α expression showed prognostic significance with respect to OS with hazard ratios (HRs) of 1.572 (95% CI: 1.001-2.467, p = 0.049) and 1.624 (95% CI: 1.047-2.520, p = 0.031) for the internal and external validation cohort, respectively. CONCLUSION: ER-α expression was a biomarker of poor prognosis and it might inform treatment decision for high risk CRC patients. However, PR expression was not associated with survival outcomes.

Clear cell carcinomas of the ovary and kidney: clarity through genomics.

Clear cell ovarian carcinoma (CCOC) and clear cell renal cell carcinoma (ccRCC) both feature clear cytoplasm, owing to the accumulation of cytoplasmic glycogen. Genomic studies have demonstrated several mutational similarities between these two diseases, including frequent alterations in the chromatin remodelling SWI-SNF and cellular proliferation phosphoinositide 3-kinase-mammalian target of rapamycin pathways, as well as a shared hypoxia-like mRNA expression signature. Although many targeted treatment options have been approved for advanced-stage ccRCC, CCOC patients are still treated with conventional platinum and taxane chemotherapy, to which they are resistant. To determine the extent of similarity between these malignancies, we performed unsupervised clustering of mRNA expression data from these cancers. This review highlights the similarities and differences between these two clear cell carcinomas to facilitate knowledge translation within future research efforts. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Overexpression screens identify conserved dosage chromosome instability genes in yeast and human cancer.

Somatic copy number amplification and gene overexpression are common features of many cancers. To determine the role of gene overexpression on chromosome instability (CIN), we performed genome-wide screens in the budding yeast for yeast genes that cause CIN when overexpressed, a phenotype we refer to as dosage CIN (dCIN), and identified 245 dCIN genes. This catalog of genes reveals human orthologs known to be recurrently overexpressed and/or amplified in tumors. We show that two genes, TDP1, a tyrosyl-DNA-phosphdiesterase, and TAF12, an RNA polymerase II TATA-box binding factor, cause CIN when overexpressed in human cells. Rhabdomyosarcoma lines with elevated human Tdp1 levels also exhibit CIN that can be partially rescued by siRNA-mediated knockdown of TDP1 Overexpression of dCIN genes represents a genetic vulnerability that could be leveraged for selective killing of cancer cells through targeting of an unlinked synthetic dosage lethal (SDL) partner. Using SDL screens in yeast, we identified a set of genes that when deleted specifically kill cells with high levels of Tdp1. One gene was the histone deacetylase RPD3, for which there are known inhibitors. Both HT1080 cells overexpressing hTDP1 and rhabdomyosarcoma cells with elevated levels of hTdp1 were more sensitive to histone deacetylase inhibitors valproic acid (VPA) and trichostatin A (TSA), recapitulating the SDL interaction in human cells and suggesting VPA and TSA as potential therapeutic agents for tumors with elevated levels of hTdp1. The catalog of dCIN genes presented here provides a candidate list to identify genes that cause CIN when overexpressed in cancer, which can then be leveraged through SDL to selectively target tumors.

TERT promoter mutation in adult granulosa cell tumor of the ovary.

The telomerase reverse transcriptase (TERT) gene is highly expressed in stem cells and silenced upon differentiation. Cancer cells can attain immortality by activating TERT to maintain telomere length and telomerase activity, which is a crucial step of tumorigenesis. Two somatic mutations in the TERT promoter (C228T; C250T) have been identified as gain-of-function mutations that promote transcriptional activation of TERT in multiple cancers, such as melanoma and glioblastoma. A recent study investigating TERT promoter mutations in ovarian carcinomas found C228T and C250T mutations in 15.9% of clear cell carcinomas. However, it is unknown whether these mutations are frequent in other ovarian cancer subtypes, in particular, sex cord-stromal tumors including adult granulosa cell tumors. We performed whole-genome sequencing on ten adult granulosa cell tumors with matched normal blood and identified a TERT C228T promoter mutation in 50% of tumors. We found that adult granulosa cell tumors with mutated TERT promoter have increased expression of TERT mRNA and exhibited significantly longer telomeres compared to those with wild-type TERT promoter. Extension cohort analysis using allelic discrimination revealed the TERT C228T mutation in 51 of 229 primary adult granulosa cell tumors (22%), 24 of 58 recurrent adult granulosa cell tumors (41%), and 1 of 22 other sex cord-stromal tumors (5%). There was a significant difference in overall survival between patients with TERT C228T promoter mutation in the primary tumors and those without it (p = 0.00253, log-rank test). In seven adult granulosa cell tumors, we found the TERT C228T mutation present in recurrent tumors and absent in the corresponding primary tumor. Our data suggest that TERT C228T promoter mutations may have an important role in progression of adult granulosa cell tumors.

Origin and Radiative Forcing of Black Carbon Aerosol: Production and Consumption Perspectives.

Air pollution, a threat to air quality and human health, has attracted ever-increasing attention in recent years. In addition to having local influence, air pollutants can also travel the globe via atmospheric circulation and international trade. Black carbon (BC), emitted from incomplete combustion, is a unique but representative particulate pollutant. This study tracked down the BC aerosol and its direct radiative forcing to the emission sources and final consumers using the global chemical transport model (MOZART-4), the rapid radiative transfer model for general circulation simulations (RRTM), and a multiregional input-output analysis (MRIO). BC was physically transported (i.e., atmospheric transport) from western to eastern countries in the midlatitude westerlies, but its magnitude is near an order of magnitude higher if the virtual flow embodied in international trade is considered. The transboundary effects on East and South Asia by other regions increased from about 3% (physical transport only) to 10% when considering both physical and virtual transport. The influence efficiency on East Asia was also large because of the comparatively large emission intensity and emission-intensive exports (e.g., machinery and equipment). The radiative forcing in Africa imposed by consumption from Europe, North America, and East Asia (0.01 Wm-2) was even larger than the total forcing in North America. Understanding the supply chain and incorporating both atmospheric and virtual transport may improve multilateral cooperation on air pollutant mitigation both domestically and internationally.

LINE-1 retrotransposon-mediated DNA transductions in endometriosis associated ovarian cancers.

OBJECTIVE: Endometrioid (ENOC) and clear cell ovarian carcinoma (CCOC) share a common precursor lesion, endometriosis, hence the designation endometriosis associated ovarian cancers (EAOC). Long interspersed nuclear element 1 (LINE-1 or L1), is a family of mobile genetic elements activated in many cancers capable of moving neighboring DNA through 3' transductions. Here we investigated the involvement of specific L1-mediated transductions in EAOCs. METHODS: Through whole genome sequencing, we identified active L1-mediated transductions originating within the TTC28 gene in 34% (10/29) of ENOC and 31% (11/35) of CCOC cases. We used PCR and capillary sequencing to assess the presence of specific TTC28-L1 transductions in formalin-fixed paraffin-embedded (FFPE) blocks from six different anatomical sites (five tumors and one normal control) for four ENOC and three CCOC cases, and compared the results to the presence of single nucleotide variations (SNVs)/frame shift (fs) mutations detected using multiplex PCR and next generation sequencing. RESULTS: TTC28-L1 mediated transductions were identified in at least three tumor samplings in all cases, and were present in all five tumor samplings in 5/7 (71%) cases. In these cases, KRAS, PIK3CA, CTNNB1, ARID1A, and PTEN mutations were found across all tumor sites while other selected SNV/fs mutations of unknown significance were present at varying allelic frequencies. CONCLUSION: The TTC28-L1 transductions along with classical driver mutations were near ubiquitous across the tumors, suggesting that L1 activation likely occurred early in the development of EAOCs. TTC28-L1 transductions could potentially be used to determine clonal relationships and to track ovarian cancer progression.

NAIL, a software toolset for inferring, analyzing and visualizing regulatory networks.

UNLABELLED: The wide variety of published approaches for the problem of regulatory network inference makes using multiple inference algorithms complex and time-consuming. Network Analysis and Inference Library (NAIL) is a set of software tools to simplify the range of computational activities involved in regulatory network inference. It uses a modular approach to connect different network inference algorithms to the same visualization and network-based analyses. NAIL is technology-independent and includes an interface layer to allow easy integration of components into other applications. AVAILABILITY AND IMPLEMENTATION: NAIL is implemented in MATLAB, runs on Windows, Linux and OSX, and is available from SourceForge at https://sourceforge.net/projects/nailsystemsbiology/ for all researchers to use. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Multifocal endometriotic lesions associated with cancer are clonal and carry a high mutation burden.

Endometriosis is a significant risk factor for clear cell and endometrioid ovarian cancers and is often found contiguous with these cancers. Using whole-genome shotgun sequencing of seven clear cell ovarian carcinomas (CCC) and targeted sequencing in synchronous endometriosis, we have investigated how this carcinoma may evolve from endometriosis. In every case we observed multiple tumour-associated somatic mutations in at least one concurrent endometriotic lesion. ARID1A and PIK3CA mutations appeared consistently in concurrent endometriosis when present in the primary CCC. In several cases, one or more endometriotic lesions carried the near-complete complement of somatic mutations present in the index CCC tumour. Ancestral mutations were detected in both tumour-adjacent and -distant endometriotic lesions, regardless of any cytological atypia. These findings provide objective evidence that multifocal benign endometriotic lesions are clonally related and that CCCs arising in these patients progress from endometriotic lesions that may already carry sufficient cancer-associated mutations to be considered neoplasms themselves, albeit with low malignant potential. We speculate that genomically distinct classes of endometriosis exist and that ovarian endometriosis with high mutational burden represents one class at high risk for malignant transformation.

Investigation of the feasibility of elective irradiation to neck level Ib using intensity-modulated radiotherapy for patients with nasopharyngeal carcinoma: a retrospective analysis.

BACKGROUND: To assess the feasibility of elective neck irradiation to level Ib in nasopharyngeal carcinoma (NPC) using intensity-modulated radiation therapy (IMRT). METHODS: We retrospectively analyzed 1438 patients with newly-diagnosed, non-metastatic and biopsy-proven NPC treated with IMRT. RESULTS: Greatest dimension of level IIa LNs (DLN-IIa) ≥ 20 mm and/or level IIa LNs with extracapsular spread (ES), oropharynx involvement and positive bilateral cervical lymph nodes (CLNs) were independently significantly associated with metastasis to level Ib LN at diagnosis. No recurrence at level Ib was observed in the 904 patients without these characteristics (median follow-up, 38.7 months; range, 1.3-57.8 months), these patients were classified as low risk. Level Ib irradiation was not an independent risk factor for locoregional failure-free survival, distant failure-free survival, failure-free survival or overall survival in low risk patients. The frequency of grade ≥ 2 subjective xerostomia at 12 months after radiotherapy was not significantly different between low risk patients who received level Ib-sparing, unilateral level Ib-covering or bilateral level Ib-covering IMRT. CONCLUSION: Level Ib-sparing IMRT should be safe and feasible for patients without a DLN-IIa ≥ 20 mm and/or level IIa LNs with ES, positive bilateral CLNs or oropharynx involvement at diagnosis. Further investigations based on specific criteria for dose constraints for the submandibular glands are warranted to confirm the benefit of elective level Ib irradiation.

A four-miRNA signature identified from genome-wide serum miRNA profiling predicts survival in patients with nasopharyngeal carcinoma.

Recent findings have reported that human serum microRNAs (miRNAs) can be used as prognostic biomarkers in various cancers. We aimed to explore the prognostic value of serum miRNAs in nasopharyngeal carcinoma (NPC) patients. The level of serum miRNA was retrospectively analyzed in 512 NPC patients recruited between January 2001 and December 2006. In the discovery stage, a microarray followed by reverse transcription-quantitative polymerase chain reaction was used to identify differentially altered miRNAs in eight patients with shorter survival and eight patients with longer survival who were well matched by age, sex and clinical stage. The identified serum miRNAs were then validated in all 512 samples, which were randomly divided into a training set and a validation set. Four serum miRNAs (miR-22, miR-572, miR-638 and miR-1234) were found to be differentially altered and were used to construct a miRNA signature. Risk scores were calculated to classify the patients into high- or low-risk groups. Patients with high-risk scores had poorer overall survival [hazard ratio (HR), 2.54; 95% confidence interval (CI), 1.57-4.12; p < 0.001] and distant metastasis-free survival (HR, 3.28; 95% CI, 1.82-5.94; p < 0.001) than those with low-risk scores in the training set; these results were confirmed in the validation and combined sets. The miRNA signature and TNM stage were independent prognostic factors. The combination of the miRNA signature and TNM stage had a better prognostic value than the TNM stage or miRNA signature alone. The four-serum miRNA signature may add prognostic value to the TNM staging system and provide information for personalized therapy in NPC.

MRI-detected skull-base invasion: prognostic value and therapeutic implication in intensity-modulated radiotherapy treatment for nasopharyngeal carcinoma.

PURPOSE: With advances in imaging and radiotherapy, the prognostic value of skull-base invasion in nasopharyngeal carcinoma (NPC) needs to be reassessed. We aimed to define a classification system and evaluate the prognostic value of the classification of magnetic resonance imaging (MRI)-detected skull-base invasion in NPC treated with intensity-modulated radiotherapy (IMRT). PATIENTS AND MATERIALS: We retrospectively reviewed 749 patients who underwent MRI and were subsequently histologically diagnosed with nondisseminated NPC and treated with IMRT. RESULTS: MRI-detected skull-base invasion was not found to be an independent prognostic factor for overall survival (OS), distant metastasis-free survival (DMFS), local relapse-free survival (LRFS), or disease-free survival (DFS; p > 0.05 for all). Skull-base invasion was classified according to the incidence of each site (type I sites inside pharyngobasilar fascia and clivus vs. type II sites outside pharyngobasilar fascia). The 5-year OS, DMFS, LRFS, and DFS rates in the classification of skull-base invasion in NPC were 83 vs. 67 %, 85 vs.75 %, 95 vs. 88 %, and 76 vs. 62 %, respectively (p < 0.05 for all). Multivariate analysis indicated the classification of skull-base invasion was an independent prognostic factor. CONCLUSION: MRI-detected skull-base invasion is not an independent prognostic factor in patients with NPC treated with IMRT. However, classification according to the site of invasion has prognostic value. Therefore, patients with various subclassifications of stage T3 disease may receive treatment with different intensities; however, further studies are warranted to prove this.

Serologic biomarkers of Epstein-Barr virus correlate with TNM classification according to the seventh edition of the UICC/AJCC staging system for nasopharyngeal carcinoma.

This study aimed to investigate the association between Epstein-Barr virus (EBV)-related biomarkers and TNM classification according to the seventh edition of AJCC/UICC staging system for nasopharyngeal carcinoma. Serum VCA-IgA and EA-IgA titers and plasma EBV-DNA load were quantified at baseline in 779 patients; the rates of positivity and titers/load were compared by TNM classification. The VCA-IgA-positive rate was significantly associated with advanced N classification and stage; the EA-IgA-positive rate with advanced T and N classifications and stage; the EBV-DNA-positive rate with advanced T, N and M classifications and stage. The percentage of triple-positive patients was higher in patients with advanced TNM classification. The VCA-IgA titer and EA-IgA titer correlated positively with T classification, N classification and disease stage (1:117 in Stage I, 1:188.4 in Stage II, 1:231.12 in Stage III, 1:265.91 in Stage IV, and 1:18.34 in Stage I, 1:32.11 in Stage II, 1:34.77 in Stage III, 1:37.65 in Stage IV, respectively). EBV DNA load correlated positively with T, N and M classification and stage [median lg (EBV DNA): 0 (IQ range 0-1.85) in Stage I, 1.32 (0-3.51) in Stage II, 3.33 (0-4.30) in Stage III, 3.83 (2.85-4.71) in Stage IV]. Serum VCA-IgA/EA-IgA titers and plasma EBV DNA correlated strongly with TNM classification according to the seventh edition of the AJCC/UICC; however, plasma EBV DNA load could accurately predict metastatic disease. EBV serological biomarkers may enhance the accuracy of TNM staging and help to avoid excessive imaging examinations in routine evaluation.

Proposal of a clinical typing system and generation of a prognostic model in patients with nasopharyngeal carcinoma from Southern China.

PURPOSE: To propose a novel clinical typing classification focusing on the distinct progression patterns of nasopharyngeal carcinoma (NPC), to supplement our knowledge of the clinical-biological behavior, to provide useful knowledge for treatment planning, and to contribute to basic research in NPC. METHODS: 632 consecutive patients were retrospectively reviewed and analyzed according to the novel typing system. We considered that NPC can be divided into 5 types as follows: limited (L), ascending (A), descending (D) ascending- descending (mixed) (AD), and distant metastasis types (M). The distribution of these clinical types, their association with Epstein-Barr virus (EBV) serology and prognostic value were explored. RESULTS: 55 (8.70%), 59 (9.34%), 177 (28.01%), 321 (50.79%) and 20 (3.16%) patients were classified as Type L, A, D, AD and M, respectively. EBV (VCA)-IgA titers, EBV early antigen (EA)-IgA serum titers, and capsid antigen lg(EBV DNA) were positively associated with the clinical typing (p<0.05). The 3-year overall survival (OS) rates for Types L, A, D, AD and M were 100, 100, 95.10, 88.20 and 59.30%, respectively (p<0.001). A prognostic model was constructed based on pretreatment lg (EBV DNA) and clinical type, which were independent predictors of OS (multivariate Cox proportional model). The prognostic model stratified patients into 4 risk subgroups. The 3-year OS rates of the low, intermediate, high and extremely high risk groups were 99.5, 90.0, 85.5 and 53.2%, respectively (p<0.001). Compared with the low-risk group, the risk of death was 4.96, 8.75 and 35.9 in the intermediate, high and extremely high risk groups, respectively (p<0.001). The model also predicted OS independently of TNM classification. CONCLUSION: This novel clinical typing system and prognostic model can supplement TNM classification, and may help design novel treatment strategies, evaluate risk stratification and investigate the varied biological characteristics of NPC.

Severe pediatric COVID-19: a review from the clinical and immunopathophysiological perspectives.

BACKGROUND: Coronavirus disease 2019 (COVID-19) tends to have mild presentations in children. However, severe and critical cases do arise in the pediatric population with debilitating systemic impacts and can be fatal at times, meriting further attention from clinicians. Meanwhile, the intricate interactions between the pathogen virulence factors and host defense mechanisms are believed to play indispensable roles in severe COVID-19 pathophysiology but remain incompletely understood. DATA SOURCES: A comprehensive literature review was conducted for pertinent publications by reviewers independently using the PubMed, Embase, and Wanfang databases. Searched keywords included "COVID-19 in children", "severe pediatric COVID-19", and "critical illness in children with COVID-19". RESULTS: Risks of developing severe COVID-19 in children escalate with increasing numbers of co-morbidities and an unvaccinated status. Acute respiratory distress stress and necrotizing pneumonia are prominent pulmonary manifestations, while various forms of cardiovascular and neurological involvement may also be seen. Multiple immunological processes are implicated in the host response to COVID-19 including the type I interferon and inflammasome pathways, whose dysregulation in severe and critical diseases translates into adverse clinical manifestations. Multisystem inflammatory syndrome in children (MIS-C), a potentially life-threatening immune-mediated condition chronologically associated with COVID-19 exposure, denotes another scientific and clinical conundrum that exemplifies the complexity of pediatric immunity. Despite the considerable dissimilarities between the pediatric and adult immune systems, clinical trials dedicated to children are lacking and current management recommendations are largely adapted from adult guidelines. CONCLUSIONS: Severe pediatric COVID-19 can affect multiple organ systems. The dysregulated immune pathways in severe COVID-19 shape the disease course, epitomize the vast functional diversity of the pediatric immune system and highlight the immunophenotypical differences between children and adults. Consequently, further research may be warranted to adequately address them in pediatric-specific clinical practice guidelines.

A foundation model for clinical-grade computational pathology and rare cancers detection.

The analysis of histopathology images with artificial intelligence aims to enable clinical decision support systems and precision medicine. The success of such applications depends on the ability to model the diverse patterns observed in pathology images. To this end, we present Virchow, the largest foundation model for computational pathology to date. In addition to the evaluation of biomarker prediction and cell identification, we demonstrate that a large foundation model enables pan-cancer detection, achieving 0.95 specimen-level area under the (receiver operating characteristic) curve across nine common and seven rare cancers. Furthermore, we show that with less training data, the pan-cancer detector built on Virchow can achieve similar performance to tissue-specific clinical-grade models in production and outperform them on some rare variants of cancer. Virchow's performance gains highlight the value of a foundation model and open possibilities for many high-impact applications with limited amounts of labeled training data.