As seen in the Journal MDPI, chronic myeloid leukemia only got its name in the mid-1800s, when doctors drew together the category based on the occurrence of a “suppuration of blood.” While the next century and a half provided a new depth on the nature of the blood cancer, new discoveries surrounding it are still being made as the medical field seeks new ways to improve patient outcomes.
The WHO set out to break down the disorder, which had become a conglomerate of conditions that are related but with slightly different biological mechanisms. A huge burst in literature on CML in recent years brought to light the variations in this cancer.
Chronic Myeloid Leukemia
Chronic myeloid leukemia (CML) is the name for a rare blood cancer that causes the uncontrolled growth of a type of white blood cell (myeloid cells) in the bone marrow, which then builds in the bone marrow and blood. This causes patients to experience fatigue, frequent bleeding, fevers, loss of appetite, paleness, bruising, weight loss, pain in the ribs, and night sweats. It begins with a chronic phase, which involves less symptoms and is easiest to treat. Later, it can evolve into the accelerated phase, during which time the disease progressively worsens before entering the blastic phase, the most severe of them all, in which symptoms accelerate to a life-threatening condition. There are various drugs to eliminate the blood cells, and other patients make use of chemotherapy or biological therapy.
The WHO Classification of Hematopoietic and Lymphoid Tumors
But while all of the patients experience illness due to a cancer of the blood, digging deeper into that revealed a large slew of distinctions. The WHO has combed through the patients with CML in order to create more specific categories. They made the ‘WHO Classification of Hematopoietic and Lymphoid Tumors,’ which developed a deep characterization system based on the molecular makeup, with categories for myeloproliferative neoplasms (MPNs) and related tumors.
The following classification emerged:
(i) CML, BCR-ABL1-positive (bearing the Philadelphia chromosome in most cases)
(ii) classical Philadelphia-negative MPNs: essential thrombocythemia, ET; polycythemia vera, PV; primary myelofibrosis, PMF
(iii) non-classical Philadelphia-negative MPNs: chronic neutrophilic leukemia, CNL; chronic eosinophilic leukemia not otherwise specified, CEL NOS
(iv) MPN, unclassifiable.
Mastocytosis, which had earlier been included in the MPN’s despite unique biological features, has now received its own disease category.
