Spontaneous mediastinal myeloid sarcoma in a common marmoset (Callithrix jacchus) and review of the veterinary literature.
Myeloid sarcoma is a rare manifestation of myeloproliferative disorder defined as an extramedullary mass composed of myeloid precursor cells. A 9-month old, female, common marmoset (Callithrix jacchus) had increased respiratory effort.



A complete necropsy with histology and immunohistochemistry was performed.



The thymus was replaced by a firm, gray-tan mass with a faint green tint, filling over 50% of the thoracic cavity. Sheets of granulocytes, lymphoid cells, nucleated erythrocytes, megakaryocytes, and hematopoietic precursors of indeterminate cell lineage replaced the thymus, perithymic connective tissue, mediastinal adipose tissues, epicardium, and much of the myocardium. The cells demonstrated diffuse strong cytoplasmic immunoreactivity for lysozyme, and strong, multifocal membranous immunoreactivity for CD117.



We report the first case of a myeloid sarcoma in a common marmoset (C. jacchus), similar to reported human cases of mediastinal myeloid sarcoma, and present a review of myeloproliferative diseases from the veterinary literature.
Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, USA.
Danielle T
DT
Morosco
Veterinary Pathology Services, The Joint Pathology Center, Silver Spring, MD, USA.
Curtis R
CR
Cline
Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, USA.
Michael A
MA
Owston
Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, USA.
Shyamesh
0000-0001-9261-2263
S
Kumar
Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX, USA.
Edward J
EJ
Dick
D000818:Animals; D002144:Callithrix; D005260:Female; D008479:Mediastinal Neoplasms / Q000175:diagnosis / Q000209:etiology / Q000662:veterinary*; D008992:Monkey Diseases / Q000175:diagnosis* / Q000209:etiology*; D023981:Sarcoma, Myeloid / Q000175:diagnosis / Q000209:etiology / Q000662:veterinary*
marmoset; myeloid sarcoma; myeloproliferative; nonhuman primate; review; thymus