Beta-2 Microglobulin (B2 M) Genomic Alterations and Absent Protein Expression in Pediatric and Adolescent Classical Hodgkin Lymphoma

Question: Genomic analysis of classical Hodgkin lymphoma (cHL) has been limited by difficulty isolating sufficient numbers of Reed-Sternberg (RS) cells from reactive background tissue. Our group has overcome this by utilizing flow cytometry to isolate RS cells followed by deep sequencing with platform optimized for ultra-low input DNA (Reichel et al, ASH 2013). Whole exome sequencing of cHL cases using this methodology revealed recurrent inactivating alterations in B2 M, including alterations in 2 of 3 pediatric and adolescent cases. In an extended cohort of adult patients, B2 M alterations clustered with the no…