[Clinical and cytological differences in adult acute lymphatic and acute undifferentiated leukemia].

The usefulness for clinical purposes of the distinction of acute undifferentiated (AUL) and acute lymphocytic leukemia (ALL) is suggested by the following observations: 1. Maturation from AUL to ALL has not been observed. Transformation of ALL to AUL has been reported i.e. less of cytoplasmic polysaccharides; however this seems rather to be the effect of cytotoxic therapy and not a real change of the cytological type. 2. Significant differences among ALL and AUL can be noted as far as the therapeutic response is concerned: All of the 9 patients with ALL but only 2 out of 9 patients with AUL went into remission. The mean survival of the cases with ALL amounts to 34, that of AUL only to 4 months. Out of the patients with ALL 4 patients are still alive in persistant first remission after 77, 57, 36 and 28 months. 3. ALL occurs most frequently in young adults (mean age of 21 patients: 31.7 years): AUL is more frequent in elderly patients (Mean age of 18 patients: 57.6 years). 4. In our material ALL did never occur consequent to a typical preluekemic stage, which was followed either by myeloblastic, monocytic, erythroleukemic or undifferentiated leukemias.