Chronic lymphocytic leukemia (CLL) is a type of cancer of the blood and bone marrow, leading to the overproduction of abnormal lymphocytes. It is a slowly progressing disease, and treatment depends on the stage of leukemia and the patient's overall health. Treatment options may include chemotherapy, immunotherapy, and targeted therapies. The assessment of the Polygenic Risk Score for chronic lymphocytic leukemia is based on the examination of 36 gene polymorphisms.
Genetic testing for chronic lymphocytic leukemia is included along with 19 other diseases in the Genetic Screening for Neoplasms and Precancerous Malformations, Polygenic Risk Score.
Causes and non-genetic risk factors
The exact causes that initiate the process of uncontrolled B-lymphocyte proliferation are unknown. Studies have identified significant chromosomal changes in the development of CLL, but it is not yet clear which genes are involved or exactly how they lead to leukemia. It has also been noted that the DNA changes associated with CLL usually occur throughout a person's life rather than being passed on from the parents (inherited). However, the following have been described as factors that may increase the risk of CLL:
- The disease mainly affects older adults, usually from the age of 60 years onwards
- It is slightly more common in men than in women
- People of Caucasian ancestry are more likely to develop chronic lymphocytic leukemia than others, such as Asians
- Exposure to herbicides (Agent Orange) and insecticides or pesticides has been associated with increased risk
- Monoclonal B-cell lymphocytosis increases the number of B cells, which may favor the development of chronic lymphocytic leukemia
Symptoms
More than 80% of patients with CLL have no symptoms, and CLL is diagnosed by a routine blood test or by chance. In the rest of the cases, the main symptoms may be:
- Asthenia, fatigue, weight loss
- Adenopathy or enlarged lymph nodes
- Repeated infections
Occasionally, the spleen (splenomegaly) or liver (hepatomegaly) may be enlarged and cause abdominal discomfort. Unlike in other blood neoplasms, fever, night sweats, and weight loss are rare.
Prevention
There are very few known risk factors for chronic lymphocytic leukemia, and most of them cannot be avoided beyond having first-degree relatives.
