Table 1

Patients’ characteristics and flow cytometric expression of different markers (percentage of positive cells) on myeloid blasts of total group and different subgroups (DR− defined as <10% of cells positive; CLIP+ defined as >35% of cells positive)

TotalPatients with DR− blastsPatients with DR+/CLIP− blastsPatients with DR+/CLIP+ blasts
A. Clinical characteristics of patients
No. of patients111117822
M/F56/555/639/3911/11
Age at diagnosis, y, mean (range)52 (16–79)46 (23–77)52 (16–77)52 (22–79)
WBCs at diagnosis67 (1–300)73 (1–300)70 (1–282)58 (1–246)
Follow-up, mo, mean (range)21 (0.03–113)21 (0.46–58)23 (0.03–113)14 (0.7–80)
CR rate, n (%)85 (75)9 (82)59 (76)15 (68)
DFS, mean (95% CI)*41 (30–53)32 (16–50)48 (34–62)11 (5–18)
FAB classification, n (%)
 AML M06 (5)2 (18)2 (3)2 (10)
 AML M117 (15)5 (46)8 (10)4 (18)
 AML M221 (19)3 (27)15 (19)3 (14)
 AML M429 (26)025 (32)4 (18)
 AML M529 (26)020 (26)9 (41)
 AML M64 (4)1 (9)3 (4)0
 RAEB-t4 (4)04 (5)0
 Not classified1 (1)01 (1)0
Cytogenetic risk group, n (%)
 Favorable9 (8)09 (11.5)0
 Standard65 (59)8 (73)45 (58)12 (55)
 Adverse17 (9)2 (18)11 (14)4 (18)
 No metaphase14 (13)011 (14)3 (13.5)
 Not done6 (5)1 (9)2 (2.5)3 (13.5)
B. Flow cytometric analysis of myeloid leukemic blasts
CD40, %25.7228.826.6
CD80, %1.30.61.60.8
CD86, %22.44.424.225.5
MHC class I, %98.89898.699.6
MHC class II, %66.21.1870.783
CLIP, %19.84.112.354.5
HLA-DM, %§55.60.6261.159.5
HLA-DO, %16.526.515.316.4
  • Abbreviations: WBC, white blood cells; CR, complete remission; DFS, disease-free survival; CI, confidence interval; RAEB-t, refractory anemia with excess blasts in transformation.

  • * Significant differences were seen in DFS between DR+/CLIP+ and DR+/CLIP− patients (P = 0.015, log-rank). Differences in other characteristics were not significant.

  • Significant differences were seen in CD40 expression between DR+ and DR− patients, (P = 0.001, Mann-Whitney U test). Differences in other characteristics were not significant.

  • Significant differences were seen in CD86 expression between DR+ and DR− patients (P = 0.003, Mann-Whitney U test). Differences in other characteristics were not significant.

  • § Significant differences were seen in HLA-DM expression between DR+ and DR− patients (P = 0.001, Mann-Whitney U test). Differences in other characteristics were not significant.