Abstract
Between September 1972 and March 1979, 169 patients suffering from Ph1-positive chronic granulocytic leukaemia (CGL) were entered into a randomized trial designed to discover whether early elective splenectomy would defer the onset of transformation and so prolong survival and whether the quality of life following transformation was improved. In contrast with the findings in the non-randomized comparison which led to this trial, no benefit of splenectomy was found in either respect. Four features recorded at presentation were found to be strongly related to prognosis; namely, spleen size, haemoglobin concentration, leucocyte count, and clinical grade. As a result of the high degree of correlation between these features, however, information on more than one allowed a prediction of prognosis that was only marginally better than that achieved by just one. Comparison with another large series illustrates the difficulty of discovering generally applicable 'staging' systems. Furthermore the prognostic features which have emerged in several large series have not been entirely consistent. On balance, for the majority of patients with no specially extreme other features, spleen size is probably as reliable an indicator of prognosis as any other feature or combination of features.