Treatment of feline injection-site sarcoma with surgery and iridium-192 brachytherapy: retrospective evaluation of 22 cats:

ObjectivesThe aim of this retrospective descriptive study was to determine the effectiveness of using iridium implants in addition to surgery in cats with feline injection-site sarcomas (FISSs) in terms of time to progression and disease-specific survival and to identify prognostic factors for patient outcome.MethodsMedical records of cats presented at our institution with FISS were reviewed. Inclusion criteria included histologic diagnosis of a tumor type associated with post-injection neoplastic development, tumor located at a site associated with vaccination, no other therapies prior to the administration of brachytherapy with the exception of surgery and adequate follow-up data.ResultsTwenty-two cats with FISS were treated with surgery and brachytherapy delivered by postoperative iridium-192 interstitial implants. Radiation doses ranged from 4000–6000 cGy (median dose 5079.55 cGy), with most doses delivered over 7 days. The median number of surgeries prior to brachytherapy was one (range 1–4). The com...