From Dog
A splenic myelolipoma in a 12-year-old Welsh Cardigan Corgi showing myeloid, erythroid, and megakaryocytic precursors with interspersed adipose tissue from a splenic myelolipoma[1]

Myelolipoma are a benign neoplasm and a variant form of lipoma containing hematopoietic tissues.

These tumors are relatively uncommon in dogs and can be found as benign splenic tumors[2], but have also been reported in the adrenal glands[3] and spinal cord.

Myelolipomas in dogs are usually diagnosed incidentally at necropsy without previous clinical signs of illness related to the tumor. However, spinal cord involvement may cause neurological deficits such as acute paraplegia[4] and large splenic masses may result in systemic signs such as weight loss, abdominal distension, vomiting, anemia and elevated ALT and ALP activity.

Diagnosis is based on presenting clinical signs, and findings of radiographic and ultrasonographic studies.

A definitive diagnosis requires histological examination of biopsied material, usually obtained during surgery.

Surgical extirpation in most cases is curative.


  1. Al-Rukibat RK et al (2006) Unusual presentation of splenic myelolipoma in a dog. Can Vet J 47(11):1112-1114
  2. Spangler WL et al (1994) Primary mesenchymal (nonangiomatous/nonlymphomatous) neoplasms occurring in the canine spleen: anatomic classification, immunohistochemistry, and mitotic activity correlated with patient survival. Vet Pathol 31(1):37-47
  3. Tursi M et al (2005) Adrenal myelolipoma in a dog. Vet Pathol 42:232–235
  4. Newman SJ et al (2000) Extradural myelolipoma in a dog. J Diagn Vet Invest 12:71–74