Diagnosis of ALK-positive anaplastic large cell lymphoma based on CD30 testing.

Prognosis in lymphoma varies widely according to the particular subtype, as does the treatment approach. Expert hematopathology review, incorporating current immunohistochemistry, genetic analysis, and fluorescent in situ hybridization (FISH), may be required to ensure an accurate diagnosis and optimal treatment. CD30 expression can be seen in a wide range of lymphomas, including Hodgkin lymphoma, anaplastic large cell lymphomas, cutaneous T-cell lymphomas, and B-cell lymphomas. The introduction of targeted therapies, such as brentuximab vedotin, makes it imperative to establish robust CD30 immunohistochemical assays in the laboratory and should encourage the judicious use of CD30 testing in order to identify potential candidates for novel therapy. Diagnosis of these patients requires close collaboration between hematopathologists and clinicians. This monograph presents 2 case studies in which immunohistochemistry changed a lymphoma diagnosis and provides a commentary on the importance of accurate diagnosis of lymphoma subtypes. Clinical Roundtable Monograph