Christen Ferguson, PharmD candidate

Leukemia is a type of cancer that affects blood cell formation and the lymphatic system. It can be classified by cell type, lymphoid or myeloid, and the rate of progression, acute or chronic.

There are 4 main subtypes of leukemia: acute lymphoid leukemia (ALL), acute myeloid leukemia (AML), chronic lymphoid leukemia (CLL), and chronic myeloid leukemia (CML). ALL and AML progress rapidly and therefore require more aggressive treatment to improve the life expectancy of the patient, whereas CLL and CML progress slowly over time and may go undiagnosed for years.

Even though leukemia is the ninth most common cancer in the United States, it accounts for just 3.7% of all new cancer diagnoses. More than 50% of leukemia cases are in individuals older than 50, and it affects men twice as often as women. The overall 5-year survival rate continues to improve and is at 63.7%, which is quadruple the rate from 1960.

ALL is more common in children and the other 3 subtypes are more common in adults. 

 portrays a projected incidence and mortality of leukemia in the United States for 2018.

 Developed countries have an overall higher incidence than developing countries. Even though the etiology has not been discovered, this could be because of higher rates of risk factors, which can be found in 

 It could also be because of enhanced medical technology for diagnosis.

The hematopoietic stem cell is responsible for producing many blood cells in the human body. The process starts when immature blast cells, lymphoid or myeloid, are released with large nuclei that eventually become mature and specialized blood cells with compacted DNA and smaller nuclei. In leukemia, the immature blast cell cannot progress in maturation because of multiple or single gene mutations that occur in the DNA. Multiple gene mutations are the result of chromosome translocation, which is an error during the cell division process. Single gene mutations arise from exposure to carcinogens or radiation that cause an isolated mutation. Because of mutations, the leukemia blast cells uncontrollably replicate in the bone marrow and take over. This is a problem, because the normal blast cells cannot use resources because of limited space. Therefore, they are unable to make mature specialized cells, such as platelets, red blood cells, and white blood cells.

 In chronic leukemia, partially mature cells develop over a long period and do not work as effectively. The most common causes are chromosomal abnormalities, such as deletions, translocation, and trisomy. CML is a result of cells dividing too quickly, while CLL is a result of defective apoptosis.

Leukemia symptoms mimic common illnesses such as influenza and musculoskeletal discomfort. Therefore, to have an accurate diagnosis of leukemia, certain criteria must be considered. For example, the clinician should perform a complete blood count with differential, a comprehensive physical exam, a medical history, and a peripheral blood smear. 

 represents peripheral blood smears of each leukemia subtype.

 lists common patient-reported symptoms associated with acute and chronic leukemia.

 summarizes the diagnosis of the 4 main leukemia subtypes.

TABLE 3. SYMPTOMS OF ACUTE AND CHRONIC LEUKEMIA

Painless lumps in the groin, neck, or underarm area

TABLE 4. DIAGNOSIS OF ACUTE AND CHRONIC LEUKEMIA

Increase in smudge cells (immature B cells)

Partial deletion on chromosome 17 TP53 sequencing

Philadelphia chromosome positive (Ph+)				

Distinguishes the blast phase from the accelerated phase

Christen Ferguson, PharmD candidate

Articles