Patients with R172-m had significantly higher midcycle blast count and slightly more cellular midcycle marrows. (A) Blasts in midcycle marrow. Violin plot for comparison of blast percentage in BMB at diagnosis and at midcycle, n = 26 for R140-m, median midcycle blast percentage 5% (range, 0-81); n = 15 for R172-m, median midcycle blast percentage 70% (range, 25-87; P < .001). A Welch 2-sample t test was used for comparison. There was no significant effect of induction type or of addition of enasidenib to induction. (B) Cellularity of midcycle marrow. Among patients with R172-m, 40% had hypercellular or normocellular midcycle bone marrows (age-adjusted cellularity), compared with 12% of the patients with R140-m. n = 25 for R140-m; n = 15 for R172-m. There was a trend toward increased cellularity among the R172-m (P = .045). A Fisher exact test was used for comparison. Midcycle BMBs were done on days 13 to 22 from induction, most on days 14 to 15. Hyper, hypercellular BMB; Hypo, hypocellular BMB; Normo, normocellular BMB.