title: Vaccine-associated rhabdomyosarcoma with spinal epidural invasion and pulmonary metastasis in a cat.
abstract: A 7-year-old, female, domestic medium-haired cat had a recurrent deep dermal mass in the interscapular region after initial surgical removal 3 months earlier. The cat had received a killed rabies vaccine and a five-in-one vaccine in the same area about 2 months prior to the first surgery. The relapsed mass was diagnosed as vaccine-associated sarcoma. The cat was euthanized 2 months later because of hind limb paralysis. At necropsy, multiple, poorly demarcated, nodular masses were seen in the muscles around the shoulders, neck, and thoracic vertebrae. Pulmonary metastasis and spinal epidural invasion at T1-T3 with regional cord compression and malacia were observed. Microscopically, the masses consisted of interwoven bundles of spindle cells with prominent multinucleated giant cell formation. The neoplastic cells stained strongly positive for myoglobin, and moderately but variably positive for vimentin, desmin, and alpha- smooth muscle actin. Phosphotungstic acid-hematoxylin staining revealed cytoplasmic striations in scattered tumor cells. The tumor was considered a vaccine-associated rhabdomyosarcoma.
authors.affiliation: Graduate Institute of Veterinary Medicine, College of Bio Resources and Agriculture, National Taiwan University, No. 1, Sec. 4, Roosevelt Road Taipei 106, Taiwan.
authors.forename: H-W
authors.initials: HW
authors.lastname: Chang
authors.forename: S-Y
authors.initials: SY
authors.lastname: Ho
authors.forename: H-F
authors.initials: HF
authors.lastname: Lo
authors.forename: Y-C
authors.initials: YC
authors.lastname: Tu
authors.forename: C-R
authors.initials: CR
authors.lastname: Jeng
authors.forename: C-H
authors.initials: CH
authors.lastname: Liu
authors.forename: F-I
authors.initials: FI
authors.lastname: Wang
authors.forename: V F
authors.initials: VF
authors.lastname: Pang
mesh_terms: D000818:Animals; D002371:Cat Diseases / Q000209:etiology* / Q000473:pathology*; D002415:Cats; D004824:Epidural Space / Q000473:pathology*; D005260:Female; D007150:Immunohistochemistry / Q000662:veterinary; D008175:Lung Neoplasms / Q000556:secondary / Q000662:veterinary*; D011819:Rabies Vaccines / Q000009:adverse effects*; D012208:Rhabdomyosarcoma / Q000209:etiology / Q000473:pathology / Q000662:veterinary*
chemical_list: D011819:Rabies Vaccines