Résumé : Skin involvement in children with acute monocytic leukemia or CD30-positive anaplastic large-cell lymphoma is well-known. In contrast, very little is known about the malignant cutaneous infiltrates in children with acute lymphoblatic leukemia (ALL) or lymphoblastic lymphoma (LBL). This study was designed to determine the frequency of these specific lesions in childhood ALL or LBL and the characteristics of such patients.