Risk factors of ifosfamide-related encephalopathy in adult patients with cancer: A retrospective analysis.

Background/purpose: Ifosfamide, a widely used chemotherapeutic agent, has been frequently associated with encephalopathy. A larger-scale study was conducted to identify risk factors of ifosfamide-related encephalopathy, including hepatic function.

Methods: Adult patients who had completed at least one cycle of ifosfamide between January 2008 and December 2010 were included. Those with renal failure or liver failure were excluded. Data were collected through chart review. Patients with encephalopathy and patients without encephalopathy were compared on age, Eastern Cooperative Oncology Group (ECOG) performance status (PS), baseline serum creatinine (SCr) level, albumin level, white blood cell count, liver function, brain metastasis, and dosage of ifosfamide. Chi-square test or Fisher's exact test, Student t test, and univariate and multivariate logistic regressions were used for analysis.

Results: This study enrolled 337 patients. Thirty-eight patients (11%) had ifosfamide-related encephalopathy. They had poorer ECOG PS; higher SCr level, white blood cell count, and aspartate aminotransferase level; and lower serum albumin level compared with patients without encephalopathy. Ifosfamide dosage, brain metastasis, and age were not significant risk factors. Multivariate analysis indicated that only ECOG PS, SCr level, and albumin level contributed significantly to the risk.

Conclusion: To date, this is the largest-scale study to have analyzed the risk factors of ifosfamide-related encephalopathy. This study confirms that an ECOG PS of 2-4 and increased SCr level are significant risk factors of ifosfamide-related encephalopathy, whereas increased albumin level decreases the risk, consistent with previous reports. Higher aspartate aminotransferase levels have no significant impact. In contrast to previous studies, ifosfamide dosage and brain metastasis are not significant contributing factors.