Open AccessTreatment of Canine Mast Cell Tumors with CCNU (Lomustine)
Author(s) -
Rassnick Kenneth M.,
Moore Antony S.,
Williams Laurel E.,
London Cheryl A.,
Kintzer Peter P.,
Engler Stephen J.,
Cotter Susan M.
Publication year - 1999
Publication title -
journal of veterinary internal medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.356
H-Index - 103
eISSN - 1939-1676
pISSN - 0891-6640
DOI - 10.1111/j.1939-1676.1999.tb02217.x
Subject(s) - lomustine , medicine , neutropenia , gastroenterology , biopsy , toxicity , cytology , mast cell , absolute neutrophil count , chemotherapy , pathology , immunology , vincristine , cyclophosphamide
The efficacy and toxicity of CCNU (1‐[2‐chloroethyl]3‐cyclohexyl‐l‐nitrosurea) were evaluated in 23 dogs with measurable mast cell tumors (MCT). Twenty‐two dogs had cutaneous MCT and 1 dog had an intranasal MCT Nineteen (83%) dogs had biopsy of their original mass performed and 4 (17%) had aspiration cytology of masses. Of the 19 tumors histologically graded, 1 (5%) neoplasm was classified as grade I, 10 (53%) were grade II, and the remaining 8 (42%) were grade III. Dogs were treated with CCNU at a dosage of 90 mg/m 2 body surface area every 3 weeks. Response could be evaluated in 19 dogs. Eight of the 19 dogs (42%) had a measurable response to CCNU. One dog had a durable complete response for 440 days. Seven dogs (37%) had a partial response for a median and mean duration of 77 days and 109 days, respectively (range, 21–254 days). Treatment with CCNU resulted in stable disease in 6 dogs (32%) for a median and mean duration of 78 days and 122 days, respectively (range, 42–347 days). The acute dose‐limiting toxicity was neutropenia 7 days after administration of CCNU. The median and mean neutrophil counts 7 days after CCNU were 1,452 cells/|μL and 1,683 cells/μ,L, respectively (n = 17). Other toxicoses were uncommon. CCNU should be considered an active agent in the treatment of MCT in dogs.