PATHOPHYSIOLOGY

General Considerations

•uterine tumors are rare and account for 0.3%-0.4% of all canine tumors

•leiomyoma accounts for 85%-90% and leiomyosarcoma accounts for 10% of uterine tumors in dogs

•leiomyomas are non-invasive, non-metastatic and slow-growing

•gross differentiation of leiomyoma and leiomyosarcoma is difficult

•congenital multiple uterine leiomyoma reported in GSD with renal cystadenocarcinoma and nodular dermatofibrosis

•others uterine tumors include adenoma, ADC, fibroma, FSA, and lipoma

CLINICAL FEATURES

Clinical Features

•middle-aged to older animals

•no breed predilections

•leiomyoma and leiomyosarcoma are usually incidental findings during ovariohysterectomy

•abdominal enlargement with palpable abdominal mass

•hydrometra or mucometra if lumen obstructed

•dysuria, hematuria, and vaginal discharge can occur with pyometra

Diagnosis

•abdominal palpation

•survey radiographs and ultrasonography to confirm origin of mass

•histopathology

Treatment

•ovariohysterectomy

•role and effectiveness of chemotherapy and radiation therapy is unknown

Prognosis

•surgical excision is curative for leiomyoma and other benign lesions

•prognosis is good for leiomyosarcoma and other malignant tumors if surgical excision is complete and there is no evidence of metastatic disease