Leiomyosarcomas affect smooth muscle tissue throughout the body and have a predisposition similar to leiomyomas, with oral mucosa, esophagus, stomach, small intestine, heart, brain, kidney, prostate, urinary bladder, uterus and skin (piloleiomyosarcoma) having been reported.
Metastases to the lungs are common.
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. Definitive diagnosis is usually obtained via histological examination of biopsy material and immunohistochemistry.
The prognosis with these tumors is guarded to poor, with a survival time of less than 1 year.
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