Chronic Lymphocytic Leukemia: What You Need to Know

Chronic lymphocytic leukemia (CLL) is the most common adult leukemia. It often grows slowly, so many people don’t feel sick at first. Still, knowing the signs, the key tests, and the main treatment options helps you make smart choices if you or someone you care about gets this diagnosis.

Recognizing CLL: Signs and tests

CLL often shows up on a routine blood test as a high white blood cell count. Common symptoms include tiredness, swollen lymph nodes (painless lumps in the neck, armpit, or groin), frequent infections, night sweats, and unexplained weight loss. Sometimes there are no symptoms and doctors watch and wait.

To confirm CLL, doctors order a complete blood count (CBC) and a blood smear, then flow cytometry to check the type of lymphocytes. Important follow-up tests include FISH for chromosome changes (like 17p deletion), TP53 mutation testing, and IGHV mutation status. These tests help predict how aggressive the disease might be and guide treatment choices.

Treatment paths and what to expect

Not everyone with CLL needs immediate treatment. If the disease is slow and you feel fine, your doctor may recommend active surveillance—regular checkups and blood tests. Treatment usually starts if you have symptoms, worsening blood counts, or rapidly growing lymph nodes or spleen.

For those who need therapy, options have changed in recent years. Targeted drugs like BTK inhibitors (ibrutinib, acalabrutinib) and BCL2 inhibitors (venetoclax) work well for many patients and often have fewer long-term side effects than classic chemo. Monoclonal antibodies (rituximab, obinutuzumab) are sometimes combined with these agents. Chemoimmunotherapy (for example, FCR) may still be used in selected younger, fit patients with favorable markers.

Side effects differ by drug: BTK inhibitors can cause bleeding, irregular heartbeat, or infections; venetoclax can cause tumor lysis syndrome early on and needs careful monitoring. Talk with your team about side-effect management and vaccination schedules—people with CLL are more infection-prone, so prevention matters.

Clinical trials remain a strong option if standard treatments are not right for you. New combinations and cellular therapies are being tested and may offer benefits when approved.

Practical questions to ask your doctor: What do my FISH/TP53/IGHV results mean? Do I need treatment now or can I wait? What side effects are likely and how will they be managed? Are there trials I should consider? Who will coordinate my care—oncologist, hematologist, or a specialized CLL clinic?

If you notice persistent lumps, unexplained fatigue, frequent infections, or odd bruising, see a doctor. Early staging and the right tests give you options. CLL often behaves slowly, and many people live long, active lives with proper monitoring and modern therapies.