A Radiomic Approach for Evaluating Intra-Subgroup Heterogeneity in SHH and Group 4 Pediatric Medulloblastoma: A Preliminary Multi-Institutional Study.

Medulloblastoma (MB) is the most frequent malignant brain tumor in children with extensive heterogeneity that results in varied clinical outcomes. Recently, MB was categorized into four molecular subgroups, WNT, SHH, Group 3, and Group 4. While SHH and Group 4 are known for their intermediate prognosis, studies have reported wide disparities in patient outcomes within these subgroups. This study aims to create a radiomic prognostic signature, medulloblastoma radiomics risk (mRRisk), to identify the risk levels within the SHH and Group 4 subgroups, individually, for reliable risk stratification. Our hypothesis is that this signature can comprehensively capture tumor characteristics that enable the accurate identification of the risk level. In total, 70 MB studies (48 Group 4, and 22 SHH) were retrospectively curated from three institutions. For each subgroup, 232 hand-crafted features that capture the entropy, surface changes, and contour characteristics of the tumor were extracted. Features were concatenated and fed into regression models for risk stratification. Contrasted with Chang stratification that did not yield any significant differences within subgroups, significant differences were observed between two risk groups in Group 4 (p = 0.04, Concordance Index (CI) = 0.82) on the cystic core and non-enhancing tumor, and SHH (p = 0.03, CI = 0.74) on the enhancing tumor. Our results indicate that radiomics may serve as a prognostic tool for refining MB risk stratification, towards improved patient care.

Development and external validation of tools for categorizing diagnosis codes in international hospital data.

BACKGROUND: The Clinical Classification Software Refined (CCSR) is a tool that groups many thousands of International Classification of Diseases 10th Revision (ICD-10) diagnosis codes into approximately 500 clinically meaningful categories, simplifying analyses. However, CCSR was developed for use in the United States and may not work well with other country-specific ICD-10 coding systems. METHOD: We developed an algorithm for semi-automated matching of Canadian ICD-10 codes (ICD-10-CA) to CCSR categories using discharge diagnoses from adult admissions at 7 hospitals between Apr 1, 2010 and Dec 31, 2020, and manually validated the results. We then externally validated our approach using inpatient hospital encounters in Denmark from 2017 to 2018. KEY RESULTS: There were 383,972 Canadian hospital admissions with 5,186 distinct ICD-10-CA diagnosis codes and 1,855,837 Danish encounters with 4,612 ICD-10 diagnosis codes. Only 46.6% of Canadian codes and 49.4% of Danish codes could be directly categorized using the official CCSR tool. Our algorithm facilitated the mapping of 98.5% of all Canadian codes and 97.7% of Danish codes. Validation of our algorithm by clinicians demonstrated excellent accuracy (97.1% and 97.0% in Canadian and Danish data, respectively). Without our algorithm, many common conditions did not match directly to a CCSR category, such as 96.6% of hospital admissions for heart failure. CONCLUSION: The GEMINI CCSR matching algorithm (available as an open-source package at https://github.com/GEMINI-Medicine/gemini-ccsr) improves the categorization of Canadian and Danish ICD-10 codes into clinically coherent categories compared to the original CCSR tool. We expect this approach to generalize well to other countries and enable a wide range of research and quality measurement applications.

Treatment response and clinical event-free survival in autoimmune hepatitis: A Canadian multicentre cohort study.

BACKGROUND & AIMS: Treatment outcomes for people living with autoimmune hepatitis (AIH) are limited by a lack of specific therapies, as well as limited well-validated prognostic tools and clinical trial endpoints. We sought to identify predictors of outcome for people living with AIH. METHODS: We evaluated the clinical course of people with AIH across 11 Canadian centres. Biochemical changes were analysed using linear mixed-effect and logistic regression. Clinical outcome was dynamically modelled using time-varying Cox proportional hazard modelling and landmark analysis. RESULTS: In 691 patients (median age 49 years, 75.4% female), with a median follow-up of 6 years (25th-75th percentile, 2.5-11), 118 clinical events occurred. Alanine aminotransferase (ALT) normalisation occurred in 63.8% of the cohort by 12 months. Older age at diagnosis (odd ratio [OR] 1.19, 95% CI 1.06-1.35) and female sex (OR 1.94, 95% CI 1.18-3.19) were associated with ALT normalisation at 6 months, whilst baseline cirrhosis status was associated with reduced chance of normalisation at 12 months (OR 0.52, 95% CI 0.33-0.82). Baseline total bilirubin, aminotransferases, and IgG values, as well as initial prednisone dose, did not predict average ALT reduction. At baseline, older age (hazard ratio [HR] 1.25, 95% CI 1.12-1.40), cirrhosis at diagnosis (HR 3.67, 95% CI 2.48-5.43), and elevated baseline total bilirubin (HR 1.36, 95% CI 1.17-1.58) increased the risk of clinical events. Prolonged elevations in ALT (HR 1.07, 95% CI 1.00-1.13) and aspartate aminotransferase (HR 1.13, 95% CI 1.06-1.21), but not IgG (HR 1.01, 95% CI 0.95-1.07), were associated with higher risk of clinical events. Higher ALT at 6 months was associated with worse clinical event-free survival. CONCLUSION: In people living with AIH, sustained elevated aminotransferase values, but not IgG, are associated with poorer long-term outcomes. Biochemical response and long-term survival are not associated with starting prednisone dose. IMPACT AND IMPLICATIONS: Using clinical data from multiple Canadian liver clinics treating autoimmune hepatitis (AIH), we evaluate treatment response and clinical outcomes. For the first time, we apply mixed-effect and time-varying survival statistical methods to rigorously examine treatment response and the impact of fluctuating liver biochemistry on clinical event-free survival. Key to the study impact, our data is 'real-world', represents a diverse population across Canada, and uses continuous measurements over follow-up. Our results challenge the role of IgG as a marker of treatment response and if normalisation of IgG should remain an important part of the definition of biochemical remission. Our analysis further highlights that baseline markers of disease severity may not prognosticate early treatment response. Additionally, the initial prednisone dose may be less relevant for achieving aminotransferase normalisation. This is important for patients and treating clinicians given the relevance and importance of side effects.