Surgical treatment of thymoma in cats: 12 cases (1987-1992).

: Twelve cats with thymoma were treated by surgical excision of the tumor alone. None of the cats received radiotherapy or chemotherapy. Two cats died or were euthanatized during the immediate postoperative period: 1 because of postsurgical hemorrhage, and the other because of an associated fungal pleuritis. None of the remaining 10 cats developed evidence of local tumor recurrence or metastases. Six of the cats were alive after follow-up periods ranging from 6 to 36 months (mean, 21 months; median, 21 months). Three cats were euthanatized 18 months, 32 months, and 45 months following surgery for unrelated problems, and 1 cat died as a result of trauma sustained 62 months postoperatively. Myasthenia gravis developed postoperatively in 2 of the cats.