LAUSR

OBJECTIVES We investigated the feasibility and utility of next-generation sequencing (NGS)-based targeted somatic mutation panels and IG/TR gene rearrangement assays in the diagnosis of lymphoproliferative disorders (LPDs) in small-volume biopsies. MATERIALS We performed a retrospective, single-institution review of all NGS assays requested over a 3-year period by hematopathologists for diagnostic purposes on small-volume biopsies. RESULTS We identified 59 small-volume biopsies. The TR assay was most commonly requested (42 [71%]), followed by the somatic mutation panel (32 [54%]) and IG assay (26 [44%]). NGS studies were associated with a change in the diagnostic line in about half of cases (28 [47%]) and in a change in the likelihood of a diagnosis in a further 16 cases (27%); there was no diagnostic impact of NGS testing in 15 cases (25%). CONCLUSIONS Implementation of NGS panel somatic mutation or IG/TR gene rearrangement assays on small-volume biopsies contributes to the diagnosis of LPDs in the majority of select cases for diagnostic purposes. The molecular diagnosis is considered in the context of the clinical, histologic, and immunophenotypic findings and does not by itself lead to a definitive diagnosis in small-volume biopsies.