Next generation sequencing in hematolymphoid neoplasia

Large scale sequencing projects over the past 2 decades have led to the identification of many common genomic alterations in hematolymphoid neoplasms, some of which with diagnostic, therapeutic, and prognostic implications [1-3]. Although these alterations can be tested individually with high sensitivity and specificity using dedicated single gene tests, it is increasingly impractical and costly to test them separately as the number of alterations grows. Instead, multiplex testing platforms that can test multiple targets in a specimen have been developed. Among these platforms, massively parallel sequencing technologies (so-called next-generation sequencing [NGS] [4]) prove to be most versatile and is increasingly being used to build tests to meet the clinical testing need. In hematolymphoid neoplasms, the early incorporation of molecular findings into the diagnostic criteria by WHO [5] has further accelerated the adoption of NGS-based tests in routine clinical practice. This article focuses on what is used in the clinical diagnostic laboratories today and is not intended to be a review of the NGS technology or its future direction. Following discussion of the 2 families of sequencing instruments from Illumina and Thermo Fisher and 3 target enrichment methods, aspects of the analysis and report of NGS results that is clinically relevant are discussed.