From Dog
Uterine leiomyoma in a bitch[1]

Leiomyoma are a common gastrointestinal stromal (smooth muscle) neoplasia of the dog.

Leiomyomas primarily affect the esophagus[2], stomach[3], colon and cecum of older dogs, but has also been reported affecting the heart[4], kidney[5] and reproductive tract[6].

Nodular dermatofibrosis has been reported in association with uterine leiomyomas in bitches[7].

Paraneoplastic syndromes observed with these tumors include hypoglycemia and high plasma erythropoietin causing secondary erythrocytosis.

Clinical signs include anorexia, fever, weight loss, tenesmus, hematochezia, rectal bleeding, peritonitis and occasionally vomiting.

Diagnosis is based on presenting clinical signs, a visible mass on endoscopic, radiographic or ultrasonic examination. Diagnosis is usually confirmed via histological examination of biopsy material.

A differential diagnosis includes lymphoma, leiomyosarcoma and squamous cell carcinoma[8].

Treatment usually requires surgical resection of the mass. Chemotherapy may be considered, using doxorubicin as a palliative therapy.

The prognosis with these tumors is guarded, with a survival time of 1 - 2 years.


  1. Kosvi.com
  2. Kook PH et al (2009) Megaesophagus secondary to an esophageal leiomyoma and concurrent esophagitis. Schweiz Arch Tierheilkd 151(10):497-501
  3. von Babo V et al (2012) Canine non-hematopoietic gastric neoplasia. Epidemiologic and diagnostic characteristics in 38 dogs with post-surgical outcome of five cases. Tierarztl Prax Ausg K Kleintiere Heimtiere 40(4):243-249
  4. Gallay J et al (2011) Cardiac leiomyoma associated with advanced atrioventricular block in a young dog. J Vet Cardiol 13(1):71-77
  5. Laluha P et al (2006) Leiomyoma of a kidney in a dog: a rare diagnosis. Schweiz Arch Tierheilkd 148(6):303-307
  6. Sycamore KF & Julian AF (2011) Lipoleiomyoma of the reproductive tract in a Huntaway bitch. N Z Vet J 59(5):244-247
  7. Zanatta M et al (2012) Nodular Dermatofibrosis in a Dog without a Renal Tumour or a Mutation in the Folliculin Gene. J Comp Pathol Aug 4
  8. Willard MD (2012) Alimentary neoplasia in geriatric dogs and cats. Vet Clin North Am Small Anim Pract 42(4):693-706