Uterine leiomyosarcomas are tumors arising from the myometrium and are primarily encountered in perimenopausal and postmenopausal women. Abnormal vaginal bleeding is often the only symptom. The diagnosis, unfortunately, is often made in the advanced stages of the disease and so a poor overall prognosis is observed. Imaging studies and biopsy are necessary steps during the workup.
Although uterine leiomyosarcoma (ULMS) is a rare tumor of the female reproductive system (constituting only 1% of all uterine malignancies), it is a highly malignant and rapidly progressing neoplastic disease [1] [2] [3]. A specific risk factor for ULMS is yet to be identified, but various reports have associated obesity, diabetes mellitus, previous pelvic radiation, and the use of tamoxifen with an increased risk for this type of malignancy [4] [5]. The clinical presentation is somewhat nonspecific, but abnormal vaginal bleeding is the most important complaint, as it is observed in up to 90% of cases [1]. In addition to vaginal bleeding, other notable symptoms are pelvic pain or pressure in the area (predominantly because of uterine enlargement, which is seen in 70% of women) and dysmenorrhea [1] [4]. ULMS is exclusively seen in perimenopausal and menopausal women, and despite the fact that up to 60% of patients are diagnosed when the tumor is still confined to the uterus, the overall prognosis is quite poor [1] [4] [5]. The primary reason is a very high rate of tumor recurrence and a poor response to adjuvant radiation and/or chemotherapy, but a delayed diagnosis is equally responsible for such outcomes [2] [6]. The 5-year survival rates range from 76% in early stages to 29% when distant metastases are present, implying that an early diagnosis may drastically improve the outlook [5].
The diagnosis of a uterine leiomyosarcoma must be made early on, and perimenopausal or menopausal women who report abnormal vaginal bleeding must be thoroughly investigated to exclude ULMS as a possible cause. Firstly, a detailed patient history needs to be obtained, which will focus on the timing and progression of symptoms, whereas a complete physical examination, with an emphasis on abdominal and pelvic palpation, is the second step of the workup. If initial signs and symptoms point to a pathology of the female reproductive tract, imaging procedures must be carried out. A heterogeneous uterine mass is detected on standard abdominal ultrasonography (US), which may be a useful initial method, but the diagnosis of a ULMS requires more advanced diagnostic studies [6]. Computed tomography (CT), but more frequently magnetic resonance imaging (MRI), are mandatory in determining the stage of the tumor [1] [5]. According to the International Federation of Gynecology and Obstetrics (FIGO) classification system, ULMS is categorized into four stages [5]:
Biopsy and subsequent histopathological examination with immunohistochemistry should be performed whenever possible in order to confirm the exact type of the tumor. Cytologic atypia, extensive mitotic activity and the presence of necrosis are typical for ULMS, whereas the expression of androgen, estrogen and progesterone receptors, c-KIT, p53 and Ki67 is seen on immunohistochemistry [2] [7].