Case 225

Submitting Author: Orduz, Y. Rocio, MD
Institution: Clinica Colsanitas, S.A.
Additional authors:Edwin Medina, Maria Teresa Urrego, Monica Zapata, Amarantho Suarez
Session: Acute leukemias of ambiguous lineage

HISTORY

May/2009: 7 year-old child with asthenia and fatigue.

DETAILS

Bone marrow biopsy from the iliac crest

Buffered formalin fixation

EDTA decalcification

In the BM smears there is an infiltration by undifferentiated blast. Normal hematopoiesis is almost absent.

BM biopsy has a 99% cellularity and diffuse infiltration by the same population described.

IMMUNOHISTOCHEMISTRY AND FLOW CYTOMETRY

Blast are positive for CD34 and CD3c. These are also positive in part with CD117 and MPO by flow cytometry and BM immunohistochemistry.

CYTOGENETIC FINDINGS

46 XY

MOLECULAR FINDINGS

None

INTERESTING FEATURES

T/Myeloid leukemia is very rare accounting for less than 1% of leukemias overall. It is more frequent in male children like in our case. The prognosis is poor and there is not a standard therapy because the multipotencial capability of the cell. In fact, this child had a relapse in September of 2010 and died.

PROPOSED DIAGNOSIS

Acute leukemia of ambiguous lineage

CONSENSUS DIAGNOSIS

Mixed phenotype acute leukemia, T/myeloid, NOS