Table 1.
Characteristics of HDMTX courses
| Variable | N (%) |
|---|---|
|
| |
| Number of courses | 100 |
| Age, years, median (IQR) | 51 (19–69) |
| Underlying disease | |
| Osteosarcoma | 36 (36) |
| Primary central nervous system lymphoma | 30 (30) |
| Non-Hodgkin’s lymphoma | 21 (21) |
| Breast cancer | 7 (7) |
| Chronic lymphocytic leukemia | 3 (3) |
| Other | 3 (3) |
| Baseline kidney function | |
| Serum creatinine, mg/dL, median (IQR) | 0.85 (0.70–1.00) |
| Chemotherapy | |
| MTX dose, g/m2, median (IQR) | 3.5 (3.5–12) |
| Received MTX as a single agent | 64 (64) |
| Received MTX with other cytotoxic chemotherapy | 36 (36) |
| High-dose leucovorin rescue | |
| Received | 81 (81) |
| Did not receive | 19 (19) |
| Dose, g/day, median (IQR) | 1.0 (1.0–1.5) |
| Within 48 hours of MTX therapy | 67 (83) |
| Beyond 48 hours of MTX therapy | 14 (17) |
| Nephrotoxicity | |
| Serum creatinine, peak, mg/dL, median (IQR) | 1.80 (1.20–2.53) |
| Fold change increase from baseline, median (IQR) | 2.0 (1.44–3.05) |
| MTX levels, μg/L, median (IQR) | |
| 24 hours after MTX dose | 69 (39.5–100) |
| 48 hours after MTX dose | 6.9 (4.05–16.45) |
| 72 hours after MTX dose | 2.04 (1.3–5.0) |
| Myelosuppression | |
| MTX alone | 64 (64) |
| Neutropenia, grade III–IV | 16 (25) |
| Thrombocytopenia, grade III–IV | 15 (23) |
| Neutropenia or thrombocytopenia | 24 (38) |
| MTX with other cytotoxic chemotherapy | 36 (36) |
| Neutropenia, grade III–IV | 13 (36) |
| Thrombocytopenia, grade III–IV | 10 (28) |
| Neutropenia or thrombocytopenia | 18 (50) |
| Infection | 21 (21) |
| Mucositis, grade I–III | 17 (1) |
| Diarrhea | 6 (6) |
| Death (attributed to MTX) | 0 (0) |
HDMTX=high-dose methotrexate; IQR=interquartile range; MTX=methotrexate.