Comparative Cancer Program, Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY.
Phase I Evaluation of CCNU (Lomustine) in Tumor-Bearing Cats
Version of Record online: 28 JUN 2008
© 2001 American College of Veterinary Internal Medicine
Journal of Veterinary Internal Medicine
Volume 15, Issue 3, pages 196–199, May 2001
How to Cite
Rassnick, K. M., Gieger, T. L., Williams, L. E., Ruslander, D. M., Northrup, N. C., Kristal, O., Myers, N. C. and Moore, A. S. (2001), Phase I Evaluation of CCNU (Lomustine) in Tumor-Bearing Cats. Journal of Veterinary Internal Medicine, 15: 196–199. doi: 10.1111/j.1939-1676.2001.tb02311.x
Previously presented in part at the 19th Annual Conference of the Veterinary Cancer Society, Woods Hole, MA, November 13—16, 1999.
- Issue online: 28 JUN 2008
- Version of Record online: 28 JUN 2008
- Revised September 21, 2000; Accepted November 27, 2000
- Alkylating agent;
- Mast cell tumor;
l-(2-Chloroethyl)3-cyclohexyl-l-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50–60 mg/m2 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/μL (mean, 2,433 cells/μL; range, 0–9,694 cells/μL). The time of neutrophil nadir was variable, occurring 7–28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14–21 days after treatment. The median platelet count at the nadir was 43,500 cells/μL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50–60 mg/m2 every 6 weeks.