Long-term clinical outcome of B-cell chronic lymphocytic leukaemia patients in clinical remission phase evaluated at phenotypic level.

This retrospective study aimed to evaluate the long-term prognostic impact of phenotypic remission in B-cell chronic lymphocytic leukaemia (CLL) patients who have achieved clinical, haematological and bone-marrow complete remission (CR) after conventional chemotherapy. The clinical and phenotypic data of 77 CLL patients in CR with a median follow-up from CR achievement of 54 months (range 5-127) were analysed. 32 patients (42%) displayed a normalized phenotype as evaluated by k:lambda ratio or by CD5+/CD19+ cell numbers. Patients with normalized phenotype demonstrated a significantly higher incidence of female sex, a lower relapse rate, a trend for higher prevalence of stage A and a lower occurrence of CLL-related deaths. The relapse-free survival of patients with normalized phenotype was significantly longer (P = 0.02), whereas no difference in overall survival was found between the two groups. Interestingly, Binet's stage at diagnosis was highly predictive of the overall survival following CR achievement. From the results of the present study we conclude that a phenotype normalization at CR obtained with conventional chemotherapy indicates a higher probability of a longer CR but it does not translate into prolonged survival. Clinical features at diagnosis, such as stage distribution, are apparently stronger predictors of the final outcome. These results emphasize, however, the need for a routine assessment of the quality of response since this information could be crucial in designing therapeutic strategies for young patients suffering from advanced CLL.