RELATIONSHIP BETWEEN ENVISIA GENOMIC CLASSIFIER AND AN HRCT-DERIVED FIBROTIC INDEX FROM DATA DRIVEN TEXTURE ANALYSIS ON 50 ILD PATIENTS

Abstract

SESSION TITLE: Diffuse Lung Disease Posters SESSION TYPE: Original Investigation Posters PRESENTED ON: October 18-21, 2020 PURPOSE: The Envisia Genomic Classifier (EGC) detects molecular usual interstitial pneumonia (UIP) in transbronchial biopsy samples with high accuracy using a 190-gene machine learning classifier. EGC facilitates the diagnoses of idiopathic pulmonary fibrosis (IPF) and other interstitial lung diseases (ILD). However, the relationship between the performance of the EGC and extent of fibrosis is uncertain. Data-driven texture analysis (DTA) is an HRCT-derived measurement of lung fibrosis extent with an underlying deep learning prediction model. Its validity and reliability have been demonstrated in several IPF cohorts. In this study, we examine the relationship between extent score determined by DTA and EGC on a set of 50 patients with ILD. METHODS: 50 ILD patients enrolled in the BRAVE clinical study who had both an EGC score and a DTA measurement were evaluated. Patients were categorized as UIP, non-UIP or non-diagnostic by a central pathology review process. Clinical diagnoses were made via multi-disciplinary team (MDT). Overall correlation between EGC and DTA, expressed as percentage of lung volume classified as fibrosis, was calculated and specific patterns in each pathology category were described. RESULTS: The Pearson correlation coefficient between EGC and DTA scores on these 50 patients was 0.56. Among the 14 patients with UIP confirmed by central pathology, 11 had both a UIP call by EGC and high fibrotic extent (DTA ≥ 10%). Two patients with UIP pathology were misclassified by EGC as non-UIP but had high DTA fibrotic extent (23.6%, 36.7%). One patient was correctly classified by EGC as UIP, but with a low fibrotic extent (DTA=6.2%). This patient’s chest CT scan showed a mild interstitial abnormality (ILA) initially while follow up CT scan seven years later showed significant progression of this ILA. Among the 14 patients with non-UIP pathology, 11 had both non-UIP EGC calls and low fibrotic extent (DTA < 10%). Two patients diagnosed with hypersensitivity pneumonitis and sarcoidosis were correctly classified by EGC as non-UIP and had high fibrotic extent measured by DTA (59.0%, 57.8%). One patient with NSIP had a high fibrotic extent (DTA = 70.8%) and UIP call by EGC. Among the 22 patients with non-diagnostic pathology, 5 of the 7 patients with low fibrotic extent (DTA < 10%) had an EGC call of non-UIP and 8 of the 15 patients with DTA extent ≥ 10% had an EGC UIP call. 3 of these 8 patients had a diagnosis of IPF. CONCLUSIONS: Classification of UIP pattern by EGC appeared relatively congruent with extent of fibrosis measured by DTA. EGC can correctly classify individuals with relatively low or relatively high fibrotic extent. However, patients with low extent of disease may be more likely to have non-UIP, or non-diagnostic pathology. CLINICAL IMPLICATIONS: Combining genomic and radiologic metrics may provide additional information to help the diagnosis and treatment of ILD patients. DISCLOSURES: Employee relationship with Veracyte, Inc Please note: >$100000 Added 03/23/2020 by Sangeeta Bhorade, source=Web Response, value=Salary Employee relationship with Veracyte Please note: >$100000 Added 03/30/2020 by Jing Huang, source=Web Response, value=Salary Research support relationship with Veracyte, Inc Please note: $20001 - $100000 Added 06/15/2020 by Stephen Humphries, source=Admin input, value=Grant/Research Support Advisory Committee Member relationship with Boehringer Ingelheim Please note: $1001 - $5000 Added 06/15/2020 by Stephen Humphries, source=Admin input, value=Consulting fee Advisory Committee Member relationship with IMIDEX LLC Please note: $5001 - $20000 Added 06/15/2020 by Stephen Humphries, source=Admin input, value=Consulting fee Employee relationship with Veracyte Please note: >$100000 Added 06/01/2020 by Marla Johnson, source=Web Response, value=Salary no disclosure on file for Giulia Kennedy; Employee relationship with Veracyte Please note: >$100000 Added 03/30/2020 by Lori Lofaro, source=Web Response, value=Salary no disclosure submitted for David Lynch; no disclosure submitted for David Lynch; no disclosure submitted for David Lynch; no disclosure submitted for David Lynch; Consultant relationship with Veracyte Please note: $1001 - $5000 Added 04/03/2020 by Steven Nathan, source=Web Response, value=Honoraria Consultant relationship with United Therapeutics Please note: $5001 - $20000 Added 05/27/2020 by Steven Nathan, source=Web Response, value=Consulting fee Consultant relationship with Bellerophon Please note: $5001 - $20000 Added 05/27/2020 by Steven Nathan, source=Web Response, value=Consulting fee Speaker/Speaker's Bureau relationship with Roche-Genentech Please note: $5001 - $20000 Added 05/27/2020 by Steven Nathan, source=Web Response, value=Honoraria Speaker/Speaker's Bureau relationship with Boerhinger-Ingelheim Please note: $20001 - $100000 Added 05/27/2020 by Steven Nathan, source=Web Response, value=Honoraria Employee relationship with Veracyte Please note: >$100000 Added 03/30/2020 by Daniel Pankratz, source=Web Response, value=Salary