Giant Soft Tissue Leiomyosarcoma of the Left Lower Extremity: Case Presentation With a Review of the Literature.

Leiomyosarcoma (LMS) accounts for approximately 5-10% of soft tissue sarcomas, with an estimated incidence in the United States (US) of less than one case/200,000 persons, more frequent in women than men. Approximately two-thirds of LMSs are retroperitoneal, abdominal, and mediastinal. Localized, soft tissue LMSs represent a lower percentage, with the lower limbs and trunk being the most frequently involved sites. LMSs larger than 5 cm (so-called giants) are even rarer, and to date have been little reported in the literature. In this paper, we present the case of a giant LMS of the left lower limb in a 73-year-old patient, who had a mass for about two years, and who, after the first diagnostic biopsy, underwent limb amputation. Macroscopic and microscopic examinations confirmed the infiltration of the underlying tibial bone. We briefly discuss eight other cases described in the literature with similar size, pointing out that the parameters with the greatest impact on prognosis proved to be size >5 cm and depth of invasion. Due to the rarity of this neoplasm, little has yet been done in relation to the most suitable therapeutic treatment of such patients, and larger case series are mandated in order to be able to conduct broader-spectrum studies.