What is chronic large granular lymphocytic leukaemia (LGLL)?

If you have chronic LGLL, you may have any of the following symptoms:

• Persistent fatigue
• Pale appearance, dizziness, heart flutters and shortness of breath on exercising
• Recurring infections
• Easy bleeding/bruising
• Enlarged spleen
• Weight loss
• Fever
• Night sweats

It is possible to have no symptoms at diagnosis. Symptoms will generally appear and progress slowly in chronic LGLL.

It may be an incidental finding (blood test performed for an unrelated reason).

If you have any of the above symptoms, contact your GP and ask for a blood test.

To diagnose LGLL, your healthcare team will perform blood tests. The reason behind the blood test is because a diagnosis of LGLL can only be made:

• If you have had LGLL cells in your blood for more than six months. The increased numbers of LGLL cells should be greater than 0.5×10⁹/L (normal range is 0.25×10⁹/L).

As well as the above, you should have:

• LGLL symptoms as well as increased LGLL cells present in your blood
• Distinct cluster of differentiation (CD) proteins on T-cell LGLL and NK-cell LGLL cells. Immunophenotyping can display these CDs found on the surface of white blood cells
  • T-cell LGLL cells usually have CD3/CD8/CD57 proteins
  • NK-cell LGLL cells usually have CD2/CD16/CD56 proteins, but not the CD3 protein
• The LGLL cells all look the same and therefore come from the same abnormal population of LGLL cells. This is known as “clonality”.
• LGLL cells may show any of the following genetic mutations:
• STAT3
• STAT5B
• TNFAIP3

If the results of the blood smear are unclear, a bone marrow aspiration/biopsy can be used to confirm the diagnosis.