Immunotherapy- (Blinatumomab-) Related Lineage Switch of KMT2A/AFF1 Rearranged B-Lymphoblastic Leukemia into Acute Myeloid Leukemia/Myeloid Sarcoma and Subsequently into B/Myeloid Mixed Phenotype Acute Leukemia

Table 1

Genetic results obtained at the time of B-ALL diagnosis, transformation to AML following initiation of blinatumomab therapy, and subsequent posttransformation to MPAL upon discontinuation of blinatumomab.

Genetic testing	Diagnosis: B-ALL (10/26/2018)	Transformation: AML (02/25/2019)	Transformation: MPAL (04/18/2019)
Conventional chromosome analysis	48, XX, +X, t(4; 11)(q21; q23), +8[20]/49, idem, +X, i(X) (p10)x2, −8[2]/46, XX[1]	63∼67, XX, +X, +X, +add(X)(q22)x1∼2, +1, +2, t(4; 11)(q21; q23), +der(4)t(4; 11), +6, +7, +8, +10, +13, +14, +18, +19, +19, +20, +21, +21, +22[cp10]/46, XX[10]	48, XX, +X, t(4; 11)(q21; q23), +8[18]/64∼66, idem, +X, +add(X)(q22), +1, +2, +der(4) t(4; 11), +6, +6, +7, +10, +13, +14, +18, +19, +19, +20, +21, +21, +22[cp2]
FISH	KMT2A rearrangement (93% of 100 interphase nuclei)	Not performed	AFF1/KMT2A fusion (92% of 500 interphase nuclei)

B-ALL, B-acute lymphoblastic leukemia; AML, acute myeloid leukemia; MPAL, mixed phenotype acute leukemia; FISH, fluorescence in situ hybridization.