Color Atlas of Hematology - Practical Microscopic and Clinical ...

70Abnormalities of the White Cell SeriesDiseases of the Lymphatic System(Non-Hodgkin Lymphomas)Malignant diseases of the lymphatic system are further classified as Hodgkinand non-Hodgkin lymphomas (NHL). NHL will be discussed here becausemost NHLs can be diagnosed on the blood analysis.➤ Non-Hodgkin lymphomas arise mostly from small or blastic B-cells.➤ Small-cell NHL cells are usually leukemic and relatively indolent, of thetype of chronic lymphocytic leukemia and its variants.➤ Blastic NHL (precursor lymphoma) is not usually leukemic. An exceptionis the lymphoblastic lymphoma, which takes its course as an acutelymphocytic leukemia.➤ Plasmacytoma is an osteotropic B-cell lymphoma that releases not itscells but their products (immunoglobulins) into the bloodstream.➤ Malignant lymphogranulomatosis (Hodgkin disease) cannot be diagnosedon the basis of blood analysis. It is therefore discussed underlymph node cytology (p. 176).The modern pathological classification of lymphomas is based on morphologyand cell immunology. The updated classification system accordingto Lennert (Kiel) has been adopted in Germany and was recently modifiedto reflect the WHO classification. The definitions of stages I–IV in NHLagree with the Ann Arbor classification for Hodgkin’s disease.Classification of non-Hodgkin: comparison of the relevant classes in the Kiel and WHO classifica-Table 6ationsWHO Kiel ClinicalCharacteristicsMarker*Precursor lymphomas/leukemias➤➤Precursor-B-lymphoblasticlymphomaPrecursor B-cell active lymphoblasticleukemiaMature B-cell lymphoma➤Chronic lymphocytic leukemia– contains the lymphoplasmacytoidimmunocytomaB-lymphoblasticlymphomaB-ALLB-CLLLymphoplasmacytoidimmunocytomaAggressiveUsually indolentUsually indolent➤ B-cell prolymphocytic leukemia AggressiveTdt,CD19, 22,79 aCD5, 19,20, 23tris 12 or13 q-,11 q-, 6 q-,p 53