Skin lesions revealing neonatal acute leukemias with monocytic differentiation. A report of 3 cases.

Acute myelo-monoblastic (AMML) and acute monoblastic (AML) leukemias have a bad prognosis, especially in children when occurring in the first months of life. We report 3 cases of such leukaemias in which skin lesions preceded and revealed the leukemia. For the 3 infants, cutaneous lesions appeared about one month before the other signs of leukaemia (2 AML and 1 AMML). Skin biopsies from all 3 infants revealed a heavy dermic infiltration by large cells with round or irregular vesicular nuclei and abundant pale cytoplasm. These atypical cells did not express any lymphoid markers but reacted strongly with monocytic-macrophagic antibodies (CD68, CD13 and CD14). Two infants were treated by mitoxanthrone and cytarabine with complete remission. The third one was not treated because of a very poor general status. Skin involvement is frequent in these nonlymphoid leukaemias (30% to 50% of cases). In only 7% of cases, leukemic skin lesions precede and reveal the other signs of leukemia by weeks or months. Then, it is very important to repeat the blood cell counts and to biopsy the skin lesions in order to make a diagnosis of leukemia as early as possible.