Myeloproliferative Disorder with Intraoral Lesions in an Olive Baboon (Papio anubis)

Abstract

Spontaneous myeloid leukemia is rarely reported in non-human primates. We report a case of myeloproliferative disorder suggestive of acute myeloid leukemia with intraoral lesions in an olive baboon (Papio anubis). Clinical pathology, radiology, gross examination (pre-mortem and post-mortem), histopathology, and immunohistochemistry findings are provided. K E Y W O R D S acute myeloid leukemia, baboon, myeloid sarcoma, non-human primate >20 000/mm 3 , or an elevated serum LDH level at presentation. 11,12 This baboon had a white blood cell count of >25 000/mm 3 and LDH of 2069 U/L (normal range 89-332 U/L). Myeloid sarcoma (MS), previously known as "granulocytic sarcoma" or "chloroma", is a rare tumor strongly associated with AML and myelodysplastic syndromes. 1,2 A variety of tissues may be affected by MS, including the skin, bones, gastrointestinal tract, and upper respiratory tract. 1 Rarely, intraoral MS develops. 1 There have been few reports of MS developing in a socket following dental extraction. 1 The majority of intraoral MS occurs in patients with known AML, but it can be the first sign of AML. 1,2 There have been few case reports of MS in domestic animals involving the lung, gastrointestinal tract, lymph nodes, liver or skin in dogs and cats and the skeletal muscle in cattle. 13 MS has presented as a mediastinal mass in dogs and the common marmoset. 13,14 On initial presentation, it was presumed that this animal had a tooth root abscess. Tooth root abscesses are commonly observed in NHP and treatment options include lancing, flushing, extraction or root canal of affected teeth and systemic medications. 15,16 MS associated with AML should be considered a differential in NHPs with suspected tooth root abscess or gingival swelling and ulceration that is accompanied by unexpected hematologic abnormalities. 2