Case 336

Submitting Author: Orduz, Y. Rocio, MD
Institution: Clinica Colsanitas, S.A.
Additional authors:Edwin Medina, Maria Teresa Urrego, Monica Zapata, Maria Consuelo Gonzalez, Carlos Ramirez
Session: B Lymphoblastic Leukemia/Lymphoma

HISTORY

A 59 year-old gentleman consulted in Jan /2007 for a perineal abscess. The CBC revealed anemia, leukocytosis and thrombocytopenia. A 41% of blasts were seen in peripheral blood. Blasts were medium in size with scant cytoplasm, open chromatin and prominent nucleolus. At that moment the diagnosis was very challenge because the only marker positive in the blast population was MPO by flow cytometry and immunochemistry. So, a final diagnosis of AML was rendered. He received the standard protocol of chemotherapy for AML and was free of disease for 5 years. In Jan/2012 he consulted again and at that time he had leukocytosis, lymphocytosis and thrombocytopenia. Hemoglobin was 14.5 g/dl. LDH was elevated 540.00 (240 480)

DETAILS

Bone marrow biopsy from the iliac crest Buffered formalin fixation EDTA decalcification Jan/2007: Bone Marrow smear shows trilineage hematopoiesis diminished and 89% of medium size blasts with scant cytoplasm, presence of granules and scarce Auer rods in some of them. BM biopsy is hyper cellular 98% with a diffuse infiltration by a blast population with pink cytoplasm. Jan/2012: Bone Marrow aspirate shows 95% of blasts with scant cytoplasm, open chromatin and evident nucleolus. BM biopsy is hyper cellular 95% and it is diffusely infiltrated by a blue blast population described above.

IMMUNOHISTOCHEMISTRY AND FLOW CYTOMETRY

Flow cytometry: Jan/2007: 90% of blasts negative with CD3cyt, CD3s, CD4, CD5, CD10, CD13, CD14, CD19, CD22cyt, CD23, CD33, CD34, tdt, CD56, CD64, CD79a, kappa, lambda, HLA-DR and positive for MPO. We could not get the images because at that time we worked in a 4-colors Flow Cytometer.


Jan/2012: 95% of blasts situated in the blast window with SSC/CD45. Blasts are positive with TdT,CD34, HLA DR, CD10, CD19, CD22s (intermediate), weak for CD22cyt and CD20. Blasts are negative with MPO, CD16, CD3cyt, CD5, CD23, CD117, kappa and lambda.

Immunochemistry: Jan/2007: Neoplastic cells are negative with tdt, CD34, CD3, CD20 and strongly positive for MPO. Jan/2012: None.

CYTOGENETIC FINDINGS

Cytogenetic studies showed a normal karyotype 46 XY in 2007 and 2012.

MOLECULAR FINDINGS

None

INTERESTING FEATURES

It is an uncommon case of a unique presentation of an AML because the only positivity for MPO and 5 years later the occurrence of another kind of acute leukemia, this time of B lineage. This patient died after the second diagnosis and during the therapy for B-ALL in sepsis.

PROPOSED DIAGNOSIS

B-ALL after 5 years of remission for a AML positive only with MPO.

CONSENSUS DIAGNOSIS

Therapy-related B-acute lymphoblastic leukemia