br Patients could have received more than of
‡Patients could have received more than 1 of the specified chemotherapeutic agents. Reference to such patients is patients who did not receive any of the specified chemotherapeutic agents.
treated with conventional chemotherapy developed AKI, whereas 74% of the patients with AMLs treated with only conventional chemotherapy in our study developed AKI within 1 year after cancer diagnosis (data not shown).26 Because the KDIGO criteria are currently regarded as the standard criteria for evaluating AKI, the findings of our study may be a useful clinical reference in the future.
The 1-year cumulative incidence of AKI in our study
notable that one-half of the AKIs occurred within 2 weeks after diagnosis, with the first onset at a median 9 days after cancer diagnosis. This emphasizes the importance of closely monitoring renal functions and using the best possible nephroprotective measures, especially early after diagnosis.
The incidence of AKI differed between cancer types. Overall, the cumulative incidence of AKI was the highest in patients with hematologic malignancies both at 2 weeks and at 1 year after cancer diagnosis. The range of cumulative incidence among AKI in patients with acute leukemia was high, ranging between 45.2% and 58.5% at 2 weeks, and it Sevoflurane was extremely high, ranging between 77.2% and 88.4%, at 1 year after diagnosis. Moreover, the severity of AKI was also higher in this patient group. This implies that cautious nephroprotective measures early after diagnosis and throughout the course of treatment is particularly crucial in this group of patients. This is in accordance with a study on adults with cancer, in which patients with hematologic malignancy had a higher cumulative incidence of AKI than
those with other cancer types.11 In comparison, renal tumor was the most AKI-prone cancer in an adult study.11 Interestingly, Wilms tumor, renal tumor in children, had a cumulative incidence of AKI of 51.5% at 1 year after diagnosis, which was eighth in ranking among the cancer types in our study (Table II). At our institute, most of the patients with Wilms tumor did not have nephrotoxic chemotherapeutics administered and they did not undergo intensive treatment periods, which may explain their low incidence of AKI.
In addition to the cancer group, the occurrence of TLS, greater number of CT scans performed, administration of chemotherapy, and administration of HSCT were found to
be significant risk factors of AKI, as expected from the clinical experience.2,5,28,29 Notably, methotrexate was found to be a
significant risk factor of AKI, as found in a previous study.30 The use of high-dose methotrexate from day 14 from the initial cycle of chemotherapy and throughout the treatment course for osteosarcoma in our institute may have contributed to the gradual increase in the cumulative incidence of AKI of this cancer type. Cisplatin and carboplatin were not shown to be risk factors of AKI in current study. One of our speculations is that they were used more often for solid tumors than for hematologic malignancies. Because AKI occurs more frequently in hematologic malignancies, the effects of cancer types may have offset the risks of chemotherapeutics. On the other hand, cyclophosphamide was shown to be associated with unexpectedly high incidence of AKI in bivariate analysis.
May 2019 ORIGINAL ARTICLES
In fact, cyclophosphamide is often used for hematologic malignancies and for many of the aggressive and refractory cancers where patients can be vulnerable to AKI because of either prolonged treatment or intense therapies. Administration of HSCT was another significant risk factor of AKI in our study, as previously reported.24 In our institute, most patients with AML undergo HSCT after 2 cycles of induction chemotherapy and 2 cycles of consolidation chemotherapy over a 4-week interval, and patients with advanced NBL undergo HSCT after 7-8 cycles of chemotherapy, with a 3- to 4-week interval. Although it should be interpreted with caution, it is interesting to note that the time points when the stepwise increment of the cumulative incidence of AKI in AML and in NBL coincide with the usual time points of HSCT in these diseases are at about 5.0 months and 6.5 months from diagnosis, respectively (Figure 2, A). Patients who experienced relapse had high incidence of AKI in bivariate analysis. This may have been due to their high initial cancer stage and their intensive treatment periods. However, it was not shown to be significant in multivariable analysis.