Diagnostic assays for facilitating the diagnosis of lymphoplasmacytic lymphoma (LPL) are provided. The method comprises assessing a biological sample of the subject for the presence of a mutation at position 38182641 in chromosome 3p22.2, wherein presence of the mutation is indicative that the subject has LPL. Also, provided are targeted therapies, methods for monitoring the progression or recurrence of LPL, and a sensitive and inexpensive real-time allele specific polymerase chain reaction assay for reliable and quantitative assessments of the mutation.
