Table I.
Ifosfamide concentration levels according to CYP450 genotype
| Genotype | N (%) | Ifosfamide at 12 h Median (Q25–Q75) | P-value | Ifosfamide at 24 h Median (Q25–Q75) | P-value |
|---|---|---|---|---|---|
|
CYP2B6 rs8192709: | |||||
| T/T + C/T | 13 (14) | 18.4 (10.9–26.0) | 0.3 | 3.30 (1.3–5.9) | 0.5 |
| C/C | 80 (86) | 16.0 (14.2–31.0) | 1.9 (0.9–4.2) | ||
| rs3211371: | |||||
| T/T + C/T | 11 (11.9) | 26.5 (15.4–34.2) | 0.2 | 3.3 (1.2–9.8) | 0.5 |
| C/C | 82 (88.1) | 17.7 (11.5–25.4) | 1.9 (0.9–4.3) | ||
| rs3745274: | |||||
| T/T + G/T | 56 (60.2) | 18.8 (13.1–27.5) | 0.2 | 1.9 (1.0–4.3) | 0.6 |
| G/G | 37 (39.8) | 18.2 (8.2–25.9) | 2.0 (0.7–6.0) | ||
|
CYP2C9 rs1799853: | |||||
| T/T + C/T | 8 (8.6) | 21.7 (12.3–34.1) | 0.4 | 2.8 (1.9-5.1) | 0.02*¥ |
| C/C | 85 (91.4) | 18.3 (11.7–25.8) | 1.8 (0.9-4.6) | ||
| rs1057910: | |||||
| C/C + A/C | 3 (3.3) | 26.3 (15.3–26.3) | 0.8 | 1.5 (1.1–3.4) | 0.9 |
| A/A | 90 (96.7) | 18.2 (11.8–26.3) | 2.0 (1.0–4.5) | ||
|
CYP3A5 rs776746: | |||||
| T/T + T/C | 35 (37.7) | 16.0 (11.85–26.45) | 0.9 | 1.9 (0.82–3.7) | 0.3 |
| C/C | 58 (62.3) | 19.6 (11.4–26.8) | 2.50 (1.04–5.3) | ||
Ninety-three pediatric patients were genotyped. The ifosfamide levels are shown as the median and quartiles (Q25–Q75).
*
Using the 24 h median as a cut point the results were: RR = 1.8, 95% CI: 1.237331–2.61854, p = 0.03.
¥
A simple t-test was performed to validate the p-value (p < 0.001).