title: Ki67 reactivity in nasal and periocular squamous cell carcinomas in cats treated with electron beam radiation therapy.
abstract: Squamous cell carcinomas of sparsely haired skin are relatively common tumors in cats, and these tumors likely exhibit a rapid growth rate. Thus, we evaluated response and duration of response in relation to the Ki67 proliferative reactivity in such tumors. Seventeen cats with confirmed squamous cell carcinomas and treated with an accelerated, hypofractionated electron beam radiation protocol were included in the study. For all of them histologic grading, Ki67 reactivity, response, and disease-free interval (DFI) were evaluated. Response to therapy was excellent (94% complete response rate) with a median DFI of 414 days. Only moderate acute and few long-term adverse effects were seen. Cats with tumors with a low Ki67 reactivity had markedly shorter DFIs than cats with tumors with high Ki67 reactivity. We concluded that an accelerated, hypofractionated electron beam radiation therapy protocol is well suited for feline squamous cell carcinomas. The protocol appears especially efficacious in tumors with a high Ki67 reactivity.
authors.affiliation: Section of Diagnostic Imaging and Radiation Oncology, Vetsuisse-Faculty, University of Zurich, Switzerland. kmelzer@vetclinics.unizh.ch
authors.forename: Katja
authors.initials: K
authors.lastname: Melzer
authors.forename: Franco
authors.initials: F
authors.lastname: Guscetti
authors.forename: Carla
authors.initials: C
authors.lastname: Rohrer Bley
authors.forename: Andrea
authors.initials: A
authors.lastname: Sumova
authors.forename: Malgorzata
authors.initials: M
authors.lastname: Roos
authors.forename: Barbara
authors.initials: B
authors.lastname: Kaser-Hotz
mesh_terms: D000818:Animals; D002294:Carcinoma, Squamous Cell / Q000532:radiotherapy / Q000662:veterinary*; D002371:Cat Diseases / Q000453:epidemiology / Q000378:metabolism / Q000401:mortality / Q000532:radiotherapy*; D002415:Cats; D049109:Cell Proliferation; D018572:Disease-Free Survival; D005123:Eye; D005260:Female; D007150:Immunohistochemistry / Q000662:veterinary; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D009666:Nose; D011882:Radiotherapy, High-Energy / Q000662:veterinary; D011996:Records / Q000662:veterinary; D012189:Retrospective Studies; D012878:Skin Neoplasms / Q000532:radiotherapy / Q000662:veterinary*; D013557:Switzerland / Q000453:epidemiology
chemical_list: D019394:Ki-67 Antigen