BL - Hematologic Malignancies Flashcards
Leukemia vs lymphoma
Leukemia – malignancies where chief manifestation is of blood and marrow
Lymphoma – manifests as solid mass – can be nodal, extranodal, or both
Extramedullary myeloid tumor/granulocytic sarcoma – presents primarily as solid mass, composed of myeloid cells or their precursors
Overlap: ex. CLL/SLL are same disease – name patient gets depends on whether marrow or lymph involvement predominates
High grade vs low grade lymphoma
High grade lymphoma: presents as rapidly enlarging mass
Low grade lymphoma: may present as mildly enlarged lymph node
Acute vs chronic leukemia
Acute leukemia (high grade): hematopoieitic neoplasm with rapidly progressive course, failed production of normal marrow cells due to predominance of leukemic cells. Characterized by low platelets, low neutrophils, low RBCs. Present as very high WBC count. Chronic leukemia (low grade): used for CML or CLL. Also has increased WBC count, insidious onset. Accumulation of mature cells. Often noted incidentally by increased WBC count on CBC.
3 viruses known to have oncogenic roles in lymphoma
1) Epstein-Barr virus (EBV)
2) Human T-cell leukemia virus (HTLV-1)
3) Kaposi sarcoma herpesvirus/Human herpesvirus 8 (KSV/HHV-8)
Leukemia and lymphoma in adults vs children
Leukemia is most common childhood cancer by type
Lymphoma is third most common childhood cancer by type
WHO classification system for hematologic malignancies
Parameters: myeloid (resemble granulocytic, monocytic, erythroid, megakaryocytic, mast cells) vs. lymphoid (resemble cells of B cell, T cell, NK cell lineages) vs. other (DCs, macrophages, etc.)
Microscopic appearance of malignant cells; histologic growth patterns of malignant cells; presence/absence of specific cytogenetic findings/molecular findings; relative amount of malignant cells present in marrow or blood; presence/absence of certain cell surface markers, cytoplasmic markers, and/or nuclear markers
Acute leukemias
Rapidly growing malignancy, block in maturation resulting in accumulation of immature cells in the marrow, replacing normal marrow cells. Often blasts. Can be myeloid or lymphoid.
Myelodysplastic syndrome (MDS)
Group of conditions where marrow is overtaken by neoplastic clone that is incapable of making normal effective blood cells in one or more myeloid lineages (dysplasia). Usually characterized by cytopenia in one or more lineages.
Myeloproliferative neoplasms (MPNs)
Marrow overtaken by neoplastic clone that makes normal functioning myeloid cells, usually in multiple lineages, but makes too many of them in one or more lineages.
Classical Hodgkin lymphoma
Neoplastic cells derived from B cells
Non-Hodgkin lymphoma
All different malignancies of mature lymphocytes, excluding classical Hodgkin lymphoma and malignancies of plasma cells. NHL subdivided into B cell NHLs (more common) or T cell/NK cell NHLs (much less common).
Plasma cell neoplasms
Includes MGUS, plasmocytoma, multiple myeloma
Other hematologic malignancies
Histiocytoses, dendritic cell tumors, other rare entities
