A prospective study of the evolution of chronic lymphocytic leukaemia

The clinical course of chronic lymphocytic leukaemia (CLL) in 126 patients has been examined over the period 1961-88. The evolution of early stages, 0-I, to late stages, III-IV, occurred frequently without an orderly progression through the intermediate stages. The tumour load as judged by lymphadenopathy and splenomegaly was similar in stages II, III and IV. It would seem that stages 0-II represent a continuous spectrum of increasing tumour load, whereas stages III and IV with tumour load of equal magnitude and suppression of haemopoiesis are likely results of a change in biological behaviour of malignant lymphocytes. Stage II(S) characterised by splenomegaly and absence of lymphadenopathy seems a distinct entity with a unique clinical course. Further evolution of CLL in these patients was characterised by progressive splenomegaly, and as this became marked the clinical course was dominated by 'hypersplenism'. Splenectomy at this late stage led to rapid relief of symptoms, progressive increase of Hb and platelets to normal levels and to a quiescent phase of CLL for a considerable period. The tumour load in stage II(S) was of the same order of magnitude as in stages II, III and IV, yet the survival was similar to that in stage 0. Survival correlated with clinical stage and age at the time of diagnosis, but showed no relation to sex. The significance of these findings is further discussed.