Occult leiomyosarcoma simulating malignant ovarian tumor: A case report

Introduction and importance: Leiomyosarcoma (LMS) is a malignant tumor of the uterine smooth muscle. It is highly aggressive and accounts for 1 % of all uterine malignancies. Symptoms often include a rapidly growing mass, with an average course of illness ranging from six to eight months. Leiomyosarcomas are rare in younger individuals. Case presentation: A 31-year-old nulliparous woman was diagnosed with a suspected malignant ovarian tumor. A unilateral salpingo-oophorectomy and surgical staging were planned to preserve the patient's fertility. However, the large solid mass was found to be arising from the uterus during surgery. In light of the preference for fertility preservation, a myomectomy was performed, with subsequent pathology results showing a malignant leiomyosarcoma. Following counseling and discussion with the patient and her spouse, follow-up surgery was performed to ensure a free surgical margin. Clinical discussion: Leiomyosarcomas at a young age is very rare, and early diagnosis is quite a challenge, especially when the tumor characteristics are not atypical. Thus, surgical evaluation and staging are paramount. Conclusion: Surgical diagnosis of any mass with a history of rapid enlargement and characteristics of malignancy is very important, especially when anatomical landmarks are distorted due to the enlarged mass.