Chronic lymphocytic leukaemia: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up

Abstract

In most cases, diagnosis is based on blood counts (leukocytosisand frequently also thrombocytosis) and differential (immaturegranulocytes, from the metamyelocyte to the myeloblast, andbasophilia). Splenomegaly is present in >50% of cases of CMLin the initial chronic phase (CP), but 50% of patients areasymptomatic.Proof of diagnosis is attained by demonstration of thePhiladelphia (Ph) chromosome (22q-) resulting from thebalanced translocation t(9;22) (q34;q11), and/or the BCR-ABLrearrangement in peripheral blood or bone marrow cells. Insome cases ( 5%) a Ph chromosome cannot be detected, andconfirmation of diagnosis rests on molecular genetic methods,e.g. fluorescent in situ hybridization (FISH), or reversetranscriptase–polymerase chain reaction (RT–PCR).