Biomarkers in the Evaluation and Management of Idiopathic Pulmonary Fibrosis

Abstract

Idiopathic Pulmonary Fibrosis (IPF) is a chronic, progressive, debilitating disease of unknown etiology and a median survival from diagnosis of 3-5 years. Despite extensive research efforts, its etiology in humans still remains largely unknown, and no curative drug therapies are available. With a gradually increasing worldwide incidence, IPF still presents a major challenge in clinical research due to its appreciable heterogeneity among individual patients in disease course and the lack of easily reproducible surrogate markers for patient relevant outcomes. Currently clinicians and researchers apply a panel of functional, radiological and histopathological indices to stratify patients into distinct phenotypic patterns of disease progression. However, none of these indicators can reliably predict not only treatment responsiveness but more importantly disease behavior, thus allowing clinicians to promptly apply aggressive therapeutic approaches to prevent or ameliorate acute exacerbation. Furthermore, on the contrary to molecular biomarkers, physiologic prognosticators provide no insights into disease mechanism and thus are unlikely to identify distinct molecular phenotypes of the disease. In the dawn of the "fibromics" era the need for disease stratification based on molecular phenotypes and implementation of personalized medicine therapeutic approaches is still unmet. Molecular biomarkers lie in the core of personalized medicine and therefore represent the main focus of this review article. Limitations that hamper their widespread clinical applicability along with future perspectives on how to address these major caveats and launch IPF biomarkers to the same trajectory as to tumor biomarkers in oncology are also discussed.