Open AccessLinear‐Accelerator‐Based Modified Radiosurgical Treatment of Pituitary Tumors in Cats: 11 Cases (1997–2008)
Author(s) -
Sellon R.K.,
Fidel J.,
Houston R.,
Gavin P.R.
Publication year - 2009
Publication title -
journal of veterinary internal medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.356
H-Index - 103
eISSN - 1939-1676
pISSN - 0891-6640
DOI - 10.1111/j.1939-1676.2009.0350.x
Subject(s) - cats , medicine , radiosurgery , acromegaly , magnetic resonance imaging , adverse effect , radiation therapy , nuclear medicine , surgery , radiology , hormone , growth hormone
Objective: Determine the efficacy and safety of a linear‐accelerator‐based single fraction radiosurgical approach to the treatment of pituitary tumors in cats. Design: Retrospective study. Animals: Eleven client‐owned cats referred for treatment of pituitary tumors causing neurological signs, or poorly controlled diabetes mellitus (DM) secondary either to acromegaly or pituitary‐dependent hyperadrenocortism. Procedures: Cats underwent magnetic resonance imaging (MRI) of the brain to manually plan radiation therapy. After MRI, modified radiosurgery was performed by delivering a single large dose (15 or 20 Gy) of radiation while arcing a linear‐accelerator‐generated radiation beam around the cat's head with the pituitary mass at the center of the beam. Eight cats were treated once, 2 cats were treated twice, and 1 cat received 3 treatments. Treated cats were evaluated for improvement in endocrine function or resolution of neurological disease by review of medical records or contact with referring veterinarians and owners. Results: Improvement in clinical signs occurred in 7/11 (63.6%) of treated cats. Five of 9 cats with poorly regulated DM had improved insulin responses, and 2/2 cats with neurological signs had clinical improvement. There were no confirmed acute or late adverse radiation effects. The overall median survival was 25 months (range, 1–60), and 3 cats were still alive. Conclusions and Clinical Importance: Single fraction modified radiosurgery is a safe and effective approach to the treatment of pituitary tumors in cats.