title: Prethymic cytoplasmic CD3 negative acute lymphoblastic leukemia or acute undifferentiated leukemia: a case report.
abstract: Acute undiffentiated leukemia (AUL) is an acute leukemia with no more than one membrane marker of any given lineage. Blasts often express HLA-DR, CD34, and/or CD38 and may be positive for terminal deoxynucleotidyl transferase (TdT). The expression of CD34, HLA-DR, and CD38 has been shown in pro-T-ALL, although in this case, blasts should also express CD7 and cyCD3. However, some cases of T-ALL without CD3 in the cytoplasm and all TCR chain genes in germ line configuration are reported, features that fit well with a very early hematopoietic cell. We report a case of acute leukemia CD34+/-HLADR+CD7+CD38+cyCD3- in which a diagnosis of AUL was considered. However the blasts were also positive for CD99 and TCR delta gene rearrangement which was found on molecular studies. Therefore a differential diagnosis between AUL and an early cyCD3 negative T-ALL was debated.
authors.affiliation: Division of Hematology, Department of Oncology, Transplants and Advances in Medicine, University of Pisa, 56126 Pisa, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Cannizzo
authors.forename: Giovanni
authors.initials: G
authors.lastname: Carulli
authors.forename: Luigi
authors.initials: L
authors.lastname: Del Vecchio
authors.forename: Antonio
authors.initials: A
authors.lastname: Azzarà
authors.forename: Sara
authors.initials: S
authors.lastname: Galimberti
authors.forename: Virginia
authors.initials: V
authors.lastname: Ottaviano
authors.forename: Frederic
authors.initials: F
authors.lastname: Preffer
authors.forename: Mario
authors.initials: M
authors.lastname: Petrini