WBC malignancies Flashcards
Myeloid malignancies
arise from myeloid cells, the precursors of granulocytes, RBCs, and megakaryocytes
Lymphoid malignancies
arise from lymphoid cells: B lymphocytes (including plasma cells), T lymphocytes, or natural killer cells
Leukemia
a malignancy of myeloid OR lymphoid cells in which malignant cells are widespread in BLOOD and BONE MARROW, characterized by a) widespread infiltration of the bone marrow by malignant cells, b) malignant cells in blood, c) proliferation of a clone of malignant cells with a characteristic genetic defect for each type of leukemia, d) complications that include ANEMIA, INFECTION, and HEMORRHAGE due to dysfunctional malignant cells replacing normal RBCs, WBCs, and megakaryocytes.
Acute leukemia
Abrupt onset, presenting as acute infection or hemorrhage.
acute leukemia s/s
anemia, infection, bleeding, bone pain, enlarged lymph nodes, spleen, and liver. HA, vomiting, nerve palsies. Elevated WBC count (sometimes >100,000), but some cases have WBC counts near normal.
Acute leukemia dx
microscopic appearance of blood cells and bone marrow cells, both contain immature WBCs (blasts)
Chronic leukemia
Better prognosis than acute leukemia. Ultimately the cause of death is the same with the two leukemias: hemorrhage or infection.
Chronic leukemia s/s
fatigue, pallor, anemia, night sweats, low-grade fever, secondary infection, enlarged spleen or liver.
Lymphoma
malignancy of the lymphoid cells that grows as masses in lymph nodes or lymph organs: (primary)bone marrow, thymus. Secondary organs: lymph nodes, tonsils, spleen, nodes of GI tract. Not acute or chronic.
Myeloid malignancies
leukemias and related disorders that arise from myeloid progenitor cells, which in normal hematopoiesis develop into normal bone marrow and blood cells.
Acute myeloid leukemia
Characterized by increased number of myeloblasts in bone marrow and blood. Malignant cells crowd out normal bone marrow and granulocytes, red cells, and megakaryocytes fail to develop. May arise de novo or as a result of other myeloproliferative syndromes. 70% of leukemias. Cigarette smoking is risk factor. Onset is typically sudden.
AML s/s
anemia, infection, hemorrhage, bone pain, lymphadenopathy, enlarged spleen and liver, neurologic defects.
AML lab values
low RBCs, low granulocytes, low plts
AML dx
> 20% of bone marrow cells must be myeloblasts.
AML tx
chemotherapy. Leukemia that arises from myelodysplasia and myeloproliferative syndromes have a poor prognosis.
chronic myeloid leukemia
Rare in children, prevalence increases with age. Characteristic of CML is an abnormally small chromosome 22 and large chromosome 9. Philadelphia chromosome is the small 22. One of the genes produces tyrosine kinase which triggers the production of immature granulocytes. Chemotherapy blocks the production of tyrosine kinase. Progression is slow and has 3 phases. 1) indolent period ~3years, discovery is incidental (via anemia, leukocytosis, enlarged spleen) 2) accelerated phase, characterized by worsening anemia and thrombocytopenia and resistant to treatment, 3) evolution into AML or acute variant of lymphoid leukemia leading to infection or hemorrhage.
CML labs
neutrophils, some eosinophils and basophils. High WBC, nucleated RBCs, high plts
CML tx
imatinib (Gleevec) gives pts >90% five year survival rate
Myelodysplasia syndrome*
Group of hematopoietic progenitor cell disorders that feature ineffective myeloid cell maturation, defective hematopoiesis, and increased risk of AML development. Occur spontaneously or 6-8 years post-chemotherapy/radiation. Bone marrow is occupied by dysplastic cells that do not mature into functional cells. Risk of infection, hemorrhage, anemia.
Chronic myeloproliferative syndromes*
One condition with various expressions. All arise from myeloid progenitor cells. They share 3 common tendencies: 1) neoplasia of marrow cells 2) extramedullary hematopoiesis (clinical features are deformed, nucleated RBCs and hepatosplenomegaly) 3) progression into a final, fatal phase featuring marrow fibrosis or acute leukemia. Four disorders: chronic myeloid leukemia, polycythemia vera, malignant thrombocytopenia, primary myelofibrosis with extramedullary hematopoiesis.