Submitting Author: Sidhu, Jagmohan Singh, MD
Institution: Department of Pathology, United Health Services Hospitals, Johnson City, NY
Additional authors:Joseph King, MD, Department of Pathology and Laboratory Medicine, Guthrie Clinic, Sayre, PA
Session: AML with recurrent genetic mutations Part II

57-year-old female presented to emergency department with headache, nausea vomiting, and black-colored diarrhea.

WBC 103.5 (Refrence range: 3.6 – 11.0 k/ul)

RBC 3.88 (Refrence range: 3.8-5.2 m/ul)

HGB 11.1 (Refrence range: 12 -16 g/dl)

HCT 32.5 (Refrence range: 35 – 47%)

PLT 37 (Refrence range: 150-400 k/ul)

We received peripheral blood smear, peripheral blood for flow cytometric analysis, right iliac crest aspirate smears, and aspirate clot in 10% buffered formalin. No bone marrow core was received. Bone marrow aspirate specimen was submitted for cytogenetic analysis.

Peripheral Blood Smear: About 90% blasts were seen. About 20-25% blasts met strict criterion of “cup-like” nuclei (cup spanning at least 25% nuclear diameter). No Auer rods or cytoplasmic granules were seen in the blasts.

Bone Marrow Aspirate Smear and Clot Section: About 95% blasts were seen. At least 10-15% blasts met strict criterion of “cup-like” nuclei (cup spanning at least 25% nuclear diameter). No Auer rods or cytoplasmic granules were seen in the blasts.

Immunohistochemistry: Blasts with “cup-like” nuclei show CD34 and myeloperoxidase filling the “cup-like invaginations by immunohistochemistry. A large number of blasts show CD117 positivity on the surface and in the “cup-like invaginations by immunohistochemistry.

Flow Cytometric Analysis: CD4+ (34%), CD7+ (46%), CD11c+ (60%),CD13+ (75%),

CD33+ (98%), CD34+ (60%), CD38+ (56%), CD45+(100%), CD64+ (26%), CD117+ (60%), and HLA-DR+ (44%).

Blasts were negative for CD2, CD3, CD5, CD8,CD10, CD11b, CD14, CD15, CD16, CD19, CD20, CD56, CD71, kappa, or lambda

Cytogenetic Analysius of Bone Marrow Aspirate:

Trisomy 8 was detected in 90% metaphases examined

47,XX,+8[18]/46,XX[2]

Molecular Analysis of Bone Marrow Aspirate (ordered due to "cup-like" nuclei of the blsats);

NPM1 (Exon 12) mutation: Detected

FLT3-ITD mutation: Detected

FLT3-D835 mutation: Not detected

PML/RARA fusion transcripts: Not detected

1. We predicted the presence of both NPM1 mutation and FLT3-ITD mutation when we saw “cup-like’ nuclear morphology of myeloblasts and found both mutations. In addition, we found trisomy 8. Association of “cup-like” nuclei with both NPM1 mutation and FLT3-ITD mutation has been described [1-4]. Trisomy 8, without any other cytogenetic abnormality, has been reported in the literature only in one patient with “cup-like” acute myeloid leukemia (AML), who also had both NPM1 mutation and FLT3-ITD mutation [2].

2. Our patient had high WBC count in peripheral blood and high blast count in both peripheral blood and in bone marrow (90% of 103,500 WBCs in the peripheral blood and 95% of all nucleated cells in the bone marrow). This finding has been repeatedly mentioned in “cup-like” AML in the literature [1,3-5].

3. Our patient was a 57-year-old female. “Cup-like” AML has been reported to prefer young age (<60 years) and female gender in the literature.

4. “Cup-like” morphology was more prominent in the peripheral blood than in the bone marrow in our case. This feature has been emphasized in one study in the literature [4].

5. Our case showed CD34 expression and HLA-DR expression on 60% blasts an 44% blasts in the peripheral blood respectively. Expression of CD34 and HLA-DR is higher than that reported for most of the cup-like AML cases in the literature [1-6].

6. FAB class of our case is M1, which is the most common FAB class reported in patients with “cup-like” AML some of the studies [1-3].

7. Our case showed CD34 positivity and MPO positivity in the “cup-like” invaginations of the blasts. CD34 filling the “cups” has not been described in the literature. Filling-up of “cups” with MPO in “cup-like” AML has been shown in the pictures and mentioned in the literatur [1,2,4,6].

8. Our case was young (less than 60 years old), had FLT3 ITD mutation and showed trisomy 8 in 90% of analyzed metaphases. The presence of FLT3 ITD mutation in trisomy 8 AML has been reported to be associated with younger age and presence of trisomy 8 in all analyzed metaphases when compared to those without FLT3 ITD mutation [7[.

Refrerences

1. Park BG, Chi H, Jang S, et al. Association of cup-like nuclei in blasts with FLT3 and NPM1 mutations in acute myeloid leukemia. Ann Hematol 2012; DOI 10.1007/s00277-012-1645-5

2. Chen W, Konoplev S, Medeiros L, et al. Cup-like nuclei (prominent nuclear invaginations) in acute myeloid leukemia are highly associated with FLT3 internal tandem duplication and NPM1 mutation. Cancer 2009;115;5481-9.

3. Jalal S, Leach M, McKay P. Possible significance of cup-like blasts in acute myeloid leukemia. Br J Haematol 2009;148:182.

4. Kroschinsky FP, Schakel U, Fischer R, et al. Cup-like acute myeloid leukemia: new disease or artificial phenomenon? Haematologica 2008;93:283-6

5. Griva-Kritikou E, Goumakou E, Androutsos G, et al. Cup-like acute myeloid leukemia: a report from a single center. Haematologica 2009;94[suppl.2:;330 abs. 0820

6. Kussick SJ, Stirewalt DL, Sheets KM, et al. A distinctive nuclear morphology in acute myeloid leukemia is strongly associated with loss of HLA-DR expression and FLT internal tandem duplication. Leukemia 2004;18:1591-8.

7. Block AW, Groman AE, Wilding GE, et al. The role of FLT3 in sole trisomy 8 acute myeloid leukemia. J Clin Oncol 28:15s, 2010 (suppl; abstr 6562)

“Cup-like” Acute Myeloid Leukemia with Trisomy 8, NPM1 Exon 12 Mutation and FLT3-ITD Mutation

Acute myeloid leukemia with mutated NPM1 and "cup-like" morphology and FLT3 ITD and trisomy 8

Case 207