Toxicity
A total of 131 cycles (median: 2 cycles/patient; range: 1–10) were administered. Thirty-five cycles required dose reduction for renal damage, prolonged bone marrow suppression, and adjustment of schedule with the subsequent stem cell transplant date. Grade IV hematological toxicity included neutropenia in 127 cycles (97%), thrombocytopenia in 38 cycles (29%), and anemia in 3 cycles (2%). The median duration of grade IV neutropenia was seven days (range: 2–31) with the use of G-CSF support. The median number of transfusions for each cycle was 1 (range: 0–9) for red blood cells and 2 (range: 0–11) for platelets. Of the 43 patients, 35 (81%) required red blood cell transfusion and 37 (86%) required platelet transfusion. Grade IV thrombocytopenia was more common in relapsed cases than in primary cases (69% vs 14%, p< 0.001). Nonhematological toxicities of grade III/IV are detailed in Table 3 . Three patients (2%) developed grade III diarrhea, while none of the patients developed grade IV diarrhea. Fever of ≥38°C occurred in 58 cycles (44%), and febrile neutropenia (FN) occurred in 30 cycles (23%). Blood cultures were positive for bacteria in six patients; three of these patients required removal of catheter to control the infection (Table 3 ). Renal and liver damage improved with conservative treatment.
Patients with UGT1A1 gene polymorphism showed a higher frequency of grade IV leukopenia (64% vs. 94%) and neutropenia (94% vs. 100%) compared to wild-type patients; however, there was no difference in the frequency of grade III–IV diarrhea or FN.