Leiomyoma of deep soft tissue mimicking calcific myonecrosis

Leiomyoma of deep soft tissue is an unusual entity reported in less than 60 cases in the English literature. The lesion is now accepted as a rare neoplasm. Leiomyomata of deep soft tissue have been divided into 2 groups, those occurring primarily in women in the retroperitoneum, histologically similar to leiomyomata of the uterus, and those occurring equally in both sexes in the somatic deep soft tissues. Irrespective of location, these lesions can demonstrate calcification, and even less commonly ossification. We report a unique case of a leiomyoma of deep soft tissue that mimicked the clinical and radiographic features of calcific myonecrosis, also a rare mass forming soft-tissue lesion. Clinical and radiographic information are often critical in the diagnosis of soft-tissue lesions; however, this case demonstrates that a lesion can deviate from the standard clinical and radiographic interpretations most commonly attributed to it.