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. 2022 Mar;34(2):327-330.
doi: 10.1177/10406387221077086. Epub 2022 Jan 31.

Type A thymoma in a pet rabbit

Halley R Robson  1 , Ryan A Yanez  2 , Leanne M Magestro  1 , Stephanie J French  2 , Matti Kiupel  2
Affiliations

Type A thymoma in a pet rabbit

Halley R Robson et al. J Vet Diagn Invest. 2022 Mar.

Abstract

A 4-y-old, spayed female, mixed-breed domesticated rabbit (Oryctolagus cuniculus domesticus) was presented because of progressive bilateral exophthalmos, with a large mediastinal mass in the cranial thorax. Palliative radiation therapy was elected, and 4 fractions of 5 Gy were delivered twice weekly under general anesthesia using 3-dimensional conformal radiation therapy for a total dose of 20 Gy, guided by an on-board cone beam CT scan. Quality-of-life and respiratory rate improved before sudden death that followed an episode of dyspnea. The overall survival time following initial diagnosis was 93 d, with 68 d after the first dose of radiation. An autopsy was performed, and the mass was diagnosed as a type A thymoma. The diagnosis was confirmed with positive immunohistochemical labeling of the neoplastic cells for cytokeratin 5/6 and cytokeratin 7.

Keywords: World Health Organization; domesticated rabbits; immunohistochemistry; radiation therapy; thymoma; type A thymoma.

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Conflict of interest statement

Declaration of conflicting interests: The authors declare no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Figures

Figures 1–6.
Figures 1–6.
Type A thymoma in a pet rabbit. Figure 1. Lateral chest radiograph. The cranial thorax is expanded by a soft tissue opacity. Figure 2. A white-to-tan, firm, nodular thymic mass expands the mediastinum. Figure 3. Dense spindloid neoplastic cells compress the remaining thymus. H&E. 4× magnification. Figure 4. Neoplastic cells are arranged in interlacing streams and bundles. H&E. 20× magnification. Figure 5. Large numbers of neoplastic cells label for cytokeratin 7. Immunohistochemistry for cytokeratin 7, DAB (brown), hematoxylin counterstaining. 10× magnification. Figure 6. Occasional neoplastic cells label strongly for cytokeratin 5/6. Immunohistochemistry for cytokeratin 5/6, DAB (brown), hematoxylin counterstaining. 10× magnification.
See this image and copyright information in PMC

References

    1. Bertram CA, et al.. Neoplasia and tumor-like lesions in pet rabbits (Oryctolagus cuniculus): a retrospective analysis of cases between 1995 and 2019. Vet Pathol 2021;58:901–911. - PubMed
    1. Detterbeck FC. Clinical value of the WHO classification system of thymoma. Ann Thorac Surg 2006;81:2328–2334. - PubMed
    1. Jekl V. Respiratory disorders in rabbits. Vet Clin North Am Exot Anim Pract 2021;24:459–482. - PubMed
    1. Morrisey JK, McEntee M. Therapeutic options for thymoma in the rabbit. Sem Avian Exot Pet Med 2005;14:175–181.
    1. Sanchez-Migallon DG, et al.. Radiation therapy for the treatment of thymoma in rabbits (Oryctolagus cuniculus). J Exot Pet Med 2006;15:138–144.