%0 Journal Article
%T Retrospective evaluation of intranasal carcinomas in cats treated with external-beam radiotherapy: 42 cases.
%A Yoshikawa H
%A Gieger TL
%A Saba CF
%A Fredrickson K
%A Kubicek L
%A Haney S
%A Ruslander D
%A Kelsey KL
%A McEntee MC
%A Nolan MW
%J J Vet Intern Med
%V 35
%N 2
%D Mar 2021
%M 33660305
%F 3.175
%R 10.1111/jvim.16098
%X BACKGROUND: Little is known regarding the comparative efficacy of various irradiation strategies used to treat intranasal carcinomas (INC) in cats.
OBJECTIVE: Investigate outcomes and prognostic factors associated with survival for cats with INC.
METHODS: Forty-two cats with INC that underwent radiotherapy (RT).
METHODS: Single-arm retrospective study. Medical record review for cats with INC that underwent RT at 1 of 7 veterinary RT facilities. Irradiation protocols categorized as: definitive-intent fractionated RT (FRT), definitive-intent stereotactic RT (SRT), and palliative-intent RT (PRT). Median overall survival time (OST) and disease progression-free survival (PFS; documented by advanced transverse imaging, or recurrence of symptoms) were calculated. Associations between tumor stage, RT protocol/intent, and adjunctive treatment usage and outcome were calculated.
RESULTS: Cats underwent SRT (N = 18), FRT (N = 8), and PRT (N = 16). In multivariate modeling, cats received definitive-intent treatment (DRT; FRT/SRT) had significantly longer median PFS (504 days, [95% confidence interval (CI): 428-580 days] vs PRT 198 days [95% CI: 62-334 days]; p = 0.006) and median OST [721 days (95% CI: 527-915 days) vs 284 days (95% CI: 0-570 days); p = 0.001]). Cats that underwent second DRT course at time of recurrence lived significantly longer than cats that received 1 RT course (either DRT or PRT [median OST 824 days (95% CI: 237-1410 days) vs 434 days (95% CI: 277-591 days); p = .028]).
CONCLUSIONS: In cats with INC, DRT is associated with prolonged OST and PFS as compared to PRT. If tumor progression occurs, a second course of DRT should be considered.