tokens: CCNU ( lomustine ) toxicity in dogs : a retrospective study ( 2002 - 07 ). OBJECTIVE : To describe the incidence of haematological, renal, hepatic and gastrointestinal toxicities in tumour - bearing dogs receiving 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea ( CCNU ). DESIGN : The medical records of 206 dogs that were treated with CCNU at the Melbourne Veterinary Specialist Centre between February 2002 and December 2007 were retrospectively evaluated .