The First Case of Acute Myeloid Leukemia With t(10;11)(p13;q21);PICALM-MLLT10 Rearrangement Presenting With Extensive Skin Involvement

Abstract

Dear Editor, The PICALM-MLLT10 rearrangement (PICALM-MLLT10r) resulting from t(10;11)(p13;q21) can activate the HOXA gene cluster [1,2], which is considered to be the dominant mechanism underlying leukemic transformation [3,4]. PICALM-MLLT10r occurs in ~10% of T-cell lymphoblastic leukemia/lymphoma cases and is rarely reported in B-cell lymphoblastic leukemia/ lymphoma, mixed-phenotype acute leukemia, lymphoma, and AML [5][6][7]. We report a case of AML with PICALM-MLLT10r presenting with extensive skin lesions. The Institutional Review Board of Samsung Medical Center, Seoul, Korea approved this report and waived the need for informed consent (2022-06-093).A 39-year-old man was admitted to our hospital on February 2022 with erythematous patches on his face and trunk. The lesion had appeared on his face three months before, spread to the trunk and upper extremities, and was suspected to have lymphomatous involvement. Positron emission tomography/computed tomography revealed hypermetabolic lesions in the pancreas, anterior mediastinum, and multiple lymph nodes, including the bilateral neck, supraclavicular, axillary, and mediastinal lymph nodes. Initial complete blood count (CBC) was as follows: white blood cells, 16.69 × 10 9 /L with 75% blasts; Hb, 173 g/L; and platelets, 203 × 10 9 /L. A bone marrow smear showed 83% blasts with hypercellularity (Fig. 1A-F). Flow cytometry analysis revealed that blasts were positive for CD34, cytoplasmic MPO, CD117, CD33, and HLA-DR; weakly positive for CD7, CD64, and CD123; and negative for cytoplasmic and surface CD3, CD19, CD10, cytoplasmic CD22 and CD79a, CD4, and CD56, which was compatible with AML. Leukemic involvement of the skin lesions on the abdomen, back, and flanks in our patient was confirmed via punch biopsy (Fig. 1G-J).Cytogenetic analysis revealed a complex karyotype: 46,XY,t (10;11)(p13;q21),del(17)(p12)[16]/45,idem,der(12)t(12;17) (p12;q21),-del(17)[4] (Fig. 2A). FISH using the Vysis LSI TP53/ CEP17 dual-color probe (Abbott Laboratories, Abbott Park, IL, USA) showed 86.5% of cells with a TP53 deletion. Reverse transcription-PCR for PICALM-MLLT10r was performed using previously reported primers [8]; direct sequencing confirmed the fusion of PICALM exon 19 and MLLT10 exon 3 (Fig. 2B). Targeted next-generation sequencing (NGS) of 46 AML-related genes on NextSeq 550Dx (Illumina,

Comparison of Optical Genome Mapping With Conventional Diagnostic Methods for Structural Variant Detection in Hematologic Malignancies

“…Notably, in hematologic malignancies, a primary mechanism of oncogenesis is the formation of fusion genes by chromosomal rearrangements, resulting in loss of control over cell division and proliferation [ 1 ]. Therefore, SVs are important markers for diagnosis, therapy selection, and predicting prognosis through risk stratification in hematologic malignancies [ 2 ].…”