No abstract

BACKGROUND. Low voriconazole levels have been associated with a higher failure rate in patients with confirmed fungal infections. METHODS. Steady‐state plasma trough voriconazole levels were measured after at least 5 days of therapy in 87 patients with hematologic malignancies on 201 separate occasions (1–5 levels per patient; median, 2). Most patients (90%) had undergone allogeneic hematopoietic stem cell transplantation. The daily voriconazole dose, administered in 2 divided doses, was 200 mg (n = 4), 400 mg (n = 151), 500 mg (n = 20), 600 mg (n = 18), and 800 mg (n = 8); corresponding to 2.0–16.3 (median, 5.4) mg/kg. Plasma voriconazole levels were 0–12.5 μg/mL (median, 1.2). Voriconazole was undetectable (<0.2 μg/mL) in 15%. RESULTS. The correlation between dose and levels was weak (r = 0.14; P = .045). The median absolute daily drug dose (400 mg) was identical in groups of patients with levels of 0, 0.2 to 0.5, >0.5 to 2.0, >2.0 to 5.0, and >5.0. Whereas the daily drug dose in mg/kg was significantly higher when the levels were >5.0 μg/mL, there was no consistent relation between dose and level below that threshold. In adult patients getting standard doses of voriconazole orally, the drug levels are highly variable. Based on limited available data, between a quarter and two‐thirds of these levels could potentially be associated with a lower likelihood of response or a higher likelihood of failure. CONCLUSIONS. Future voriconazole studies should incorporate prospective therapeutic drug monitoring and consideration should be given to checking levels in patients receiving the drug for confirmed, life‐threatening fungal infections. Cancer 2007. © 2007 American Cancer Society.

BACKGROUND: Hepatocellular carcinoma (HCC) is increasing in incidence due to hepatitis C. Stereotactic body radiotherapy (SBRT) is a noninvasive, effective therapy in the management of liver malignancies. The authors evaluated radiological response in 26 patients with HCC treated with SBRT at Indiana University. METHODS: Between March 2005 and June 2008, 26 patients with HCC who were not surgical candidates were enrolled in a phase 1 to 2 trial. Eligibility criteria included solitary tumors ≤ 6 cm or up to 3 lesions with sum diameters ≤ 6 cm, and well‐compensated cirrhosis. All patients had imaging before, at 1 to 3 months, and every 3 to 6 months after SBRT. RESULTS: Patients received 3 to 5 fractions of SBRT. Median SBRT dose was 42 Gray (Gy) (range: 24‐48 Gy). Median follow‐up was 13 months. Per Response Evaluation Criteria in Solid Tumors (RECIST), 4 patients had a complete response (CR), 15 had a partial response (PR), and 7 achieved stable disease (SD) at 12 months. One patient with SD experienced progression marginal to the treated area. The overall best response rate (CR + PR) was 73%. In comparison, by European Association for the Study of the Liver (EASL) criteria, 18 of 26 patients had ≥ 50% nonenhancement at 12 months. Thirteen of 18 demonstrated 100% nonenhancement, being > 50% in 5 patients. Kaplan‐Meier 1‐ and 2‐year survival estimates were 77% and 60%, respectively. CONCLUSIONS: SBRT is effective therapy for patients with HCC with an overall best response rate (CR + PR) of 73%. Nonenhancement on imaging, a surrogate for ablation, may be a more useful indicator than size reduction in evaluating HCC response to SBRT in the first 6 to 12 months, supporting EASL criteria. Cancer 2012;118: 3191–98. © 2011 American Cancer Society.

Rasburicase was administered at a fixed dose of 3 mg to treat 287 episodes of elevated serum uric acid levels (>7 mg/dL) in 247 adult patients with hematological malignancies. The median total dose of 36 μg/kg (range: 18-65) was a fraction of the recommended total pediatric dose of 0.75-1.0 mg/kg. The median change in uric acid levels at 24 h was -4.1 mg/dL (range: -12 to +1) and -45% (range: -95 to +9). Uric acid levels normalized at 24 h in 72% of patients. There was no relationship between the weight-based dose and uric acid decline. The only predictor of success was the baseline uric acid; the failure rate was 84% with baseline level >12 mg/dL and 18% if it was ≤ 12. Uric acid levels continued to decline beyond 24 h in most patients without additional treatment. Serum creatinine remained stable over 24 h, and declined over 48 h and 7 days. There was no relationship between the extent of reduction in uric acid levels and serum creatinine. We conclude that a single 3-mg dose of rasburicase, used with close monitoring, is sufficient to treat most adults with uric acid levels up to 12 mg/dL.