Absence of the V617F JAK2 mutation in the lymphoid compartment in a patient with essential thrombocythemia and B-chronic lymphocytic leukemia and in two relatives with lymphoproliferative disorders.

BACKGROUND

Myeloproliferative neoplasms likely involve both myeloid and lymphoid lineages. Nevertheless, the coincidence of chronic myeloproliferative and lymphoproliferative diseases in the same patient is a rare phenomenon.

METHODS

We report a case of a patient having essential thrombocythemia (ET) and B-chronic lymphocytic leukemia (B-CLL). In this patient and in 2 relatives with lymphoproliferative disorders, we searched for JAK2(V617F) mutation in lymphocytes.

RESULTS

In the patient with ET and B-CLL, we identified homozygous JAK2(V617F) mutation in the granulocytic compartment. Both relatives were heterozygous for JAK2(V617F) mutation, whereas no mutation signal could be detected in the lymphoid compartment of all 3 patients.

CONCLUSION

Our results seem to confirm that CLL cases are negative for JAK2(V617F) mutation in B- and T-lymphocyte populations.Presence of JAK2(V617F) mutation in subjects without myeloproliferative diseases could indicate an increased risk of a future myeloproliferative neoplasm development.