Leiomyosarcoma of the Sigmoid Mesocolon: Report of a Case

Although leiomyosarcoma arising primarily in the sigmoid mesocolon is rare, these sarcomas can be considered a special kind of retroperitoneal tumors. The clinical features are rarely obvious because of their location and lack of symptoms. Hence, they usually attain large sizes and may have metastases to distant sites at the time of diagnosis. Most authors agree on using computer tomography (CT) and nuclear magnetic resonance imaging (MIII) as diagnostic tools, but only histological examination can confirm the diagnosis, thus making a definitive pre-operative diagnosis difficult. We report the case of a 52-year-old female with low abdominal discomfort for 2 years, who mimicked having a large uterine myoma. During laparotomy, a tumor that was 13×7×6.5 cm in size was found on the sigmoid mesocolon. Curative resection was done, and the pathology confirmed a high-grade leiomyosarcoma. The post-operative survey revealed no evidence of distant metastasis.