Diffuse gliomas are a heterogeneous group of malignancies with highly variable outcomes, and diagnosis is largely based on histologic appearance. Tumor classification according to cell type and grade provides some prognostic information. However, significant clinical and biologic heterogeneity exists in glioma, even after accounting for known clinicopathologic variables. Significant advances in knowledge of the molecular genetics of brain tumors have occurred in the past decade, largely because of the availability of high-throughput profiling techniques, including new sequencing methodologies and multidimensional profiling by The Cancer Genome Atlas project. The large amount of data generated from these efforts has enabled the identification of prognostic and predictive factors and helped to identify pathways driving tumor growth. Implementing these signatures into the clinic to personalize therapy presents a new challenge. Identification of relevant biomarkers, especially when coupled with clinical trials of newer targeted therapies, will enable better patient stratification and individualization of treatment for patients with glioma.
John F. de Groot, Erik P. Sulman, and Kenneth D. Aldape
Phillip G. Febbo, Marc Ladanyi, Kenneth D. Aldape, Angelo M. De Marzo, M. Elizabeth Hammond, Daniel F. Hayes, A. John Iafrate, R. Kate Kelley, Guido Marcucci, Shuji Ogino, William Pao, Dennis C. Sgroi, and Marian L. Birkeland
The molecular analysis of biomarkers in oncology is rapidly advancing, but the incorporation of new molecular tests into clinical practice will require a greater understanding of the genetic changes that drive malignancy, the assays used to measure the resulting phenotypes and genotypes, and the regulatory processes that new molecular biomarkers must face to be accepted for clinical use. To address these issues and provide an overview of current molecular testing in 6 major malignancies, including glioma, breast cancer, colon cancer, lung cancer, prostate cancer, and acute myelogenous leukemia, an NCCN Task Force was convened on the topic of evaluating the clinical utility of tumor markers in oncology. The output of this meeting, contained within this report, describes the ways biomarkers have been developed and used; defines common terminology, including prognostic, predictive, and companion diagnostic markers, and analytic validity, clinical validity, and clinical utility; and proposes the use of a combination level of evidence score to aid in the evaluation of novel biomarker tests as they arise. The current state of regulatory oversight and anticipated changes in the regulation of molecular testing are also addressed.