For the analysis of a suspected hematological malignancy, a complete blood count and blood film are essential, as malignant cells can show in characteristic ways on light microscopy. When there is lymphadenopathy, a biopsy from a lymph node is generally undertaken surgically. In general, a bone marrow biopsy is part of the "work up" for the analysis of these diseases. All specimens are examined microscopically to determine the nature of the malignancy. A number of these diseases can now be classified by cytogenetics (AML, CML) or immunophenotyping (lymphoma, myeloma, CLL) of the malignant cells. Classification Historically, hematological malignancies have been most commonly divided by whether the malignancy is mainly located in the blood (leukemia) or in lymph nodes (lymphomas). Relative proportions of hematological malignancies in the United States Type of hematological malignancy Percentage Total Leukemias — 30.4% Acute lymphoblastic leukemia (ALL) 4.0% Acute myelogenous leukemia (AML) 8.7% Chronic lymphocytic leukemia (CLL) sorted under lymphomas according to current WHO classification; called small lymphocytic lymphoma (SLL) when leukemic cells are absent. 10.2% Chronic myelogenous leukemia (CML) 3.7% Acute monocytic leukemia (AMoL) 0.7% Other leukemias 3.1% Lymphomas — 55.6% Hodgkin's lymphomas (all four subtypes) 7.0% Non-Hodgkin's lymphomas (all subtypes) 48.6% Myelomas 14.0% Total 100% World Health Organization 4th Edition NOS = "Not otherwise specified"
Tumors of the hematopoietic and lymphoid tissues
Oral manifestations of systemic disease
Lymphoproliferative disorders
Multisystem inflammatory syndrome in children
Effects of flooding on skin
Overwhelming post-splenectomy infection
Immune tolerance in pregnancy
Immune-mediated inflammatory diseases