Tumors of the hematopoietic and lymphoid tissues

Tumors of the hematopoietic and lymphoid tissues
Micrograph of a plasmacytoma, a hematological malignancy

Tumors of the hematopoietic and lymphoid tissues (American English) or tumours of the haematopoietic and lymphoid tissues (British English) are tumors that affect the blood, bone marrow, lymph, and lymphatic system.[1][2] Because these tissues are all intimately connected through both the circulatory system and the immune system, a disease affecting one will often affect the others as well, making aplasia, myeloproliferation and lymphoproliferation (and thus the leukemias and the lymphomas) closely related and often overlapping problems. While uncommon in solid tumors, chromosomal translocations are a common cause of these diseases. This commonly leads to a different approach in diagnosis and treatment of hematological malignancies. Hematological malignancies are malignant neoplasms ("cancer"), and they are generally treated by specialists in hematology and/or oncology. In some centers "hematology/oncology" is a single subspecialty of internal medicine while in others they are considered separate divisions (there are also surgical and radiation oncologists). Not all hematological disorders are malignant ("cancerous"); these other blood conditions may also be managed by a hematologist.

Hematological malignancies may derive from either of the two major blood cell lineages: myeloid and lymphoid cell lines. The myeloid cell line normally produces granulocytes, erythrocytes, thrombocytes, macrophages and mast cells; the lymphoid cell line produces B, T, NK and plasma cells. Lymphomas, lymphocytic leukemias, and myeloma are from the lymphoid line, while acute and chronic myelogenous leukemia, myelodysplastic syndromes and myeloproliferative diseases are myeloid in origin.

A subgroup of them are more severe and are known as haematological malignancies (British English)/hematological malignancies (American English) or blood cancer. They may also be referred to as liquid tumors.[3][4]

  1. ^ Vardiman JW, Thiele J, Arber DA, Brunning RD, Borowitz MJ, Porwit A, et al. (July 2009). "The 2008 revision of the World Health Organization (WHO) classification of myeloid neoplasms and acute leukemia: rationale and important changes". Blood. 114 (5): 937–951. doi:10.1182/blood-2009-03-209262. PMID 19357394. S2CID 3101472.
  2. ^ Stewart B, Wild CP, eds. (2014). World Cancer Report 2014. World Health Organization. pp. Chapter 5.13. ISBN 978-9283204299.
  3. ^ Juo PS (2001). Concise Dictionary of Biomedicine and Molecular Biology (2nd ed.). Hoboken: CRC Press. p. 653. ISBN 9781420041309.
  4. ^ Cancer Rehabilitation Medicine Quick Reference (RMQR). New York: Demos Medical Publishing. 2013. p. 26. ISBN 9781617050008.