Table 1.

Patient and disease characteristics of entire study cohort

Characteristic		n	%
Total cohort		94	100
Age at diagnosis	<10 years	43	46
	≥10 years	51	54
Sex	Male	62	66
	Female	32	34
Ethnicity	Hispanic	52	55
	Not Hispanic	40	43
	Unknown	2	2
Presenting WBC (/uL)	<50,000	66	70
	≥50,000	28	30
CNS Status1	CNS1	64	68
	CNS2	26	28
	CNS3	4	4
Cytogenetic classification1	Neutral	67	71
	Favorable	16	17
	Adverse	9	10
	Unknown	2	2
MPAL phenotype2	B/My	84	89
	T/My	9	10
	B/T	1	1
	B/T/My	0	0
MPAL populations3	Biphenotypic (1 pop.)	82	87
	Bilineal (2 pop.)	12	13
MPO positive4	Yes	88	94
	No	5	5
	Unknown	1	1
CD19 positive4	Yes	85	90
	No	9	10
Type of induction regimen	ALL	87	93
	AML	6	6
	Hybrid	1	1
HSCT in CR1	Yes	15	16
	No	79	84

¹As per AALL08B1.

²Phenotype designates lineages involved, B/My = B+Myeloid, T/My = T+Myeloid, B/T= B+T, B/T/My = B+T+Myeloid.

³Designates whether lineages are represented on one cell population (Biphenotypic) or two or more distinct populations (bilineal+).

⁴Presence of myeloperoxidase (MPO) or CD19 on the MPAL blasts. MPAL = mixed phenotype acute leukemia. ALL= acute lymphoblastic leukemia, AML = acute myeloid leukemia, “hybrid” = elements of both ALL and AML therapy. CNS = central nervous system involvement, HSCT = hematopoietic stem cell transplantation, CR 1 = first remission.