Common Acute Lymphoblastic Leukemia Ph＋ Following Langerhans Cell Histiocytosis in a Multi-Malformed Child with INV (9) (p12;q13) (mat):Case Report

The occurrence of Langerhans cell histiocytosis (LCH) and another malignancy in the same patient is infrequent but has been recognized. The genetic changes that could be responsible for LCH and/or concomitant leukemia development are obscure. To the best of our knowledge, this is the first description of constitutional maternally derived inv (9) (p12;q13) in an LCH patient, and also of the development of common ALL Ph after LCH diagnosis and therapy. The potential significance of these findings [inv (9)LCHALL Ph] and their mutual relationship are unknown. Therefore, cooperative studies of large numbers of patients are needed to identify the common risk factors, if any.