• 1 Yates WD, Lester SJ, Mills JH. Chemoreceptor tumors diagnosed at the Western College of Veterinary Medicine 1967-1979. Can Vet J 1980; 21:124129.

    • Search Google Scholar
    • Export Citation
  • 2 Aupperle H, Marz I, Ellenberger C, et al. Primary and secondary heart tumours in dogs and cats. J Comp Pathol 2007; 136:1826.

  • 3 Ware WA, Hopper DL. Cardiac tumors in dogs: 1982-1995. J Vet Intern Med 1999; 13:95103.

  • 4 Obradovich JE, Withrow SJ, Powers BE, et al. Carotid body tumors in the dog. Eleven cases (1978-1988). J Vet Intern Med 1992; 6:96101.

  • 5 Bianchi LC, Marchetti M, Brait L, et al. Paragangliomas of head and neck: a treatment option with CyberKnife radiosurgery. Neurol Sci 2009; 30:479485.

    • Search Google Scholar
    • Export Citation
  • 6 Gillette EL, LaRue SM, Gillette SM. Normal tissue tolerance and management of radiation injury. Semin Vet Med Surg (Small Anim) 1995; 10:209213.

    • Search Google Scholar
    • Export Citation
  • 7 Harris D, King GK, Bergman PJ. Radiation therapy toxicities. Vet Clin North Am Small Anim Pract 1997; 27:3746.

  • 8 Poulson JM, Vujaskovic Z, Gillette SM, et al. Volume and dose-response effects for severe symptomatic pneumonitis after fractionated irradiation of canine lung. Int J Radiat Biol 2000; 76:463468.

    • Search Google Scholar
    • Export Citation
  • 9 Gillette SM, Gillette EL, Shida T, et al. Late radiation response of canine mediastinal tissues. Radiother Oncol 1992; 23:4152.

  • 10 Lee N, Chan K, Bekelman JE, et al. Salvage re-irradiation for recurrent head and neck cancer. Int J Radiat Oncol Biol Phys 2007; 68:731740.

    • Search Google Scholar
    • Export Citation
  • 11 Nieder C, Milas L, Ang KK. Tissue tolerance to reirradiation. Semin Radiat Oncol 2000; 10:200209.

  • 12 Platteaux N, Dirix P, Vanstraelen B, et al. Outcome after reirradiation of head and neck cancer patients. Strahlenther Onkol 2011; 187:2331.

    • Search Google Scholar
    • Export Citation
  • 13 Turrel JM, Théon AP. Reirradiation of tumors in cats and dogs. J Am Vet Med Assoc 1988; 193:465469.

  • 14 Wondergem J, van Ravels FJ, Reijnart IW, et al. Reirradiation tolerance of the rat heart. Int J Radiat Oncol Biol Phys 1996; 36:811819.

    • Search Google Scholar
    • Export Citation
  • 15 Vicari ED, Brown DC, Holt DE, et al. Survival times of and prognostic indicators for dogs with heart base masses: 25 cases (1986-1999). J Am Vet Med Assoc 2001; 219:485487.

    • Search Google Scholar
    • Export Citation
  • 16 Ehrhart N, Ehrhart EJ, Willis J, et al. Analysis of factors affecting survival in dogs with aortic body tumors. Vet Surg 2002; 31:4448.

    • Search Google Scholar
    • Export Citation

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Use of three-dimensional conformal radiation therapy for treatment of a heart base chemodectoma in a dog

Nicholas J. Rancilio DVM1, Takashi Higuchi BVSc2, Jerome Gagnon DVM3, and Elizabeth A. McNiel DVM, PhD, DACVIM, DACVR4
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  • 1 Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824.
  • | 2 Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824.
  • | 3 Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824.
  • | 4 Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824.

Abstract

Case Description—A 9-year-old spayed female mixed-breed dog was evaluated because of a progressively worsening, nonproductive cough and gagging of 1 year's duration.

Clinical Findings—Physical examination results were unremarkable. A cranial mediastinal mass was identified at the heart base with 3-view thoracic radiography. A CT scan of the thorax revealed an invasive mass surrounding major vessels at the heart base that was not considered surgically resectable. Thoracoscopic biopsy specimens of the cranial mediastinal mass were obtained, and histologic evaluation revealed that the tumor was a chemodectoma.

Treatment and Outcome—On the basis of results of the CT scan, a 3-D conformal radiation therapy plan was generated with computer treatment-planning software. The patient was treated with external beam radiation therapy; a 6-MV linear accelerator was used to deliver a prescribed dose of 57.5 Gy in twenty-three 2.5-Gy fractions. The cough improved following radiation therapy. Prior to treatment, the tumor volume was calculated to be 126.69 cm3. Twenty-five months following radiation therapy, a follow-up CT scan was performed and there was a >50% reduction in tumor volume at that time. Disease progression causing pericardial, pleural, and peritoneal effusion and syncopal episodes occurred 32 months following radiation therapy, which were treated with pericardectomy and additional radiation therapy. The dog was still alive and doing well 42 months following initial radiation treatment.

Clinical Relevance—Conformal radiation therapy provided an additional treatment option for a nonresectable heart base chemodectoma in the dog of this report; conformal radiation therapy was reasonably tolerable and safe.

Contributor Notes

Dr. Rancilio's present address is Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, West Lafayette, IN 47907.

Dr. Takashi's present address is the Japan Small Animal Cancer Center, 2-27-4 Nakatomiminami, Tokorozawa, Saitama 359-0003, Japan.

Dr. Gagnon's present address is VCA Berwyn Animal Hospital, 2845 Harlem Ave, Berwyn, IL 60402.

Dr. McNiel's present address is the Tufts Medical Center Molecular Oncology Research Institute, 800 Washington St, Boston, MA 02111.

Address correspondence to Dr. McNiel (elizabeth.mcniel@tufts.edu).