The most common adult leukemia in Western countries, characterized by clonal proliferation of mature B lymphocytes. Often indolent with watchful waiting for early stage. Median age at diagnosis 70 years. Can transform to aggressive Richter syndrome.

• 1Biopsy
• 2Imaging (CT, MRI, PET)
• 3Tumor markers
• 4Genetic testing
• 5Endoscopy
• 6Blood tests
• 7Screening programs

Early-stage (Rai 0-II) has median survival >10 years; may not require immediate treatment. Advanced stage (Rai III-IV) has 3-5 year median survival without treatment. Modern targeted therapies (ibrutinib, venetoclax) have transformed outcomes with 85%+ response rates. 17p deletion/TP53 mutation has poorer prognosis (3-5 years) but responds to BTK inhibitors. Transformation to aggressive lymphoma (Richter transformation) occurs in 5-10% and has poor prognosis (<1 year).

• Smoking cessation
• Sun protection
• Healthy diet
• Regular exercise
• Vaccination (HPV, HBV)
• Screening programs
• Limit alcohol
• Maintain healthy weight