Atypical lymphocyte morphology: an adverse prognostic factor for disease progression in stage A CLL independent of trisomy 12.

We studied 270 patients with Binet stage A chronic lymphocytic leukaemia looking for adverse prognostic factors. In a multivariate analysis the following features were found to be risk factors for disease progression: atypical lymphocyte morphology (defined as either > 10% prolymphocytes or > 15% lymphocytes with cleaved nuclei or lymphoplasmacytoid cells); more than two karyotypic abnormalities; lymphocyte count > 30 x 10(9)/l; lymphocyte doubling time < 1 year; enlargement of one or more lymph node groups. In a univariate analysis the presence of trisomy 12 also correlated with progressive disease, but this was largely a consequence of the association between trisomy 12 and atypical lymphocyte morphology. Atypical lymphocyte morphology is an important prognostic factor in stage A CLL, and one which incurs no additional investigational cost.