Submitting Author: Jiang, Liuyan, MD
Institution: Mayo Clinic Florida
Session: Therapy-related myeloid neoplasms

35 year old female with history of breast carcinoma diagnosed in 12/2007. She received neoadjuvant chemotherapy (TAC x 6 cycles) and subsequent modified radical mastectomy in 4/2008; no residual invasive carcinoma was present in mastectomy specimen. In 4/2012, she developed thrombocytopenia; circulating blasts were identified on the peripheral blood. Bone marrow biopsy confirms the diagnosis of acute myeloid leukemia.

Received multiple attempts of chemotherapy with various agents, before and after the allogenic SCT. She had persistent and several recurrent AML with same clone. Through the course, she had developed GVHD, fungal and CMV infection. Eventually she passed away due to acute septic shock and acute hemorrhagic shock, a year after the initial diagnosis of AML

The right iliac bone marrow biopsy was lightly decalcified (1 hour) then formalin fixed.

60% blasts are identifed by 500-cell differential count on aspiration smears; many dwarf megakaryocytes are noted; and erythropoiesis show megaloblastoid changed. Iron stain does not show ringed sideroblasts. The biopsy and clot sections show marked cellularity (100%).

CBC:

RBC 3.36 x 10^6/ul

HgB 10.6 g/dL; Hct 30.3%, MCV 90.1 fL, MCH 31.5, MCHC 35.0

WBC: 3.2 x 10^3/ul

59.0% Neut, 26.0% Lymph, 1% Baso, 4% Meta, 1% Myelo, 5% Blasts

Platelet: too low to estimate

Flow cytometry analysis identified 60% blasts expressing CD13, CD33, CD15 (partial), CD117, CD34 (dim), and HLA-DR; negative for CD19 and CD10.

Immunohistochemistry show the blasts diffusely positve for myeloperoxidase and CD117; negative for CD34.

46, XX, t(6;9)(p23;q34) (DEK/NUP214)

Postive for FLT3 internal tandem duplication; negative for NPM1 mutation.

This is a typical case of AML as late complicaitons of cytotoxic chemotherapy. First of all, the AML occurs much earlier than typical cases with alkylating agent (4 years versus 5-10 years). Second, the cytogenetic abnormality is unique, and has never been reported to be associated with this particular category.

Acute myeloid leukemia, therapy related.

Therapy-related myeloid neoplasm, acute myeloid leukemia with t(6;9)(p23;q34); DEK/NUP214

Case 107