1 Hepatic Lymphoma Diagnosis

Hematopathology is a rapidly evolving subspecialty in which diagnosis often involves integration of morphology, immunophenotyping, cytogenetics, and molecular data. Many of the recent changes are highlighted in the 2016 revision to the 4th edition of the WHO classification of tumours of hematopoietic and lymphoid tissue. Lineage (i.e. B-cell, T-cell, NK-cell) and maturation (immature vs. mature) still form the basis for lymphoproliferative disorder classification; immunophenotyping is important for classification and is essentially always required for classification of lymphoma on liver biopsy. Immunophenotypic variation is expected and must be interpreted in the context of morphology and clinical presentation. Clonality assessment can be helpful in select cases, but clonality is not synonymous with malignancy and genetic changes cannot be used in isolation for diagnosis.