Multiple Leiomyomas of Uterus.

Uterine Lieomyomas or fibroids are the most common gynecological tumor in women [1]. They are benign tumors that arise from the overgrowth of the smooth muscle cells arranged in a whorl like pattern and fibrous connective tissue of the uterus. Because of the presence of estrogen and progestin receptors there is enlargement of fibroids during pregnancy and they shrink or remain stable after menopause [1]. Most uterine lieomyomas occur in the fundus of the body and only 8% occur involving the cervix. They can be rarely found within the broad ligament. Lieomyomas are classified according to their location within the uterus as submucosal, intramural and subserosal type [2]. Lieomyoma can undergo red or cystic degeneration due to lack of blood supply. Rarely these uterine Lieomyoma may undergo malignant transformation into leiomyosarcoma the reported incidence of malignant transformation is less than 1% [1]. Variants of leiomyoma are also identified such as cellular Lieomyoma which are predominantly composed of smooth muscle cells, Lipolieomyomas which contain macroscopic fat and Benign metastasizing Lieomyoma in which the myomas are found in the uterus and in extrauterine location such as lung [2]. Most women with uterine fibroids are asymptomatic. Symptoms are usually due to their location within the uterus and their size [1]. Grey scale sonography appearances of Lieomyoma are variable. They can involve the uterus diffusely or can present as focal masses. When small diffuse Lieomyoma are present, on sonography the uterus is enlarged with globular outline and has a heterogenous echotexture. Localized myomas are usually Hypoechoic with heterogenous echotexture and they form focal contour deformity. Some of them demonstrate areas of acoustic attenuation or shadowing without a discrete mass. Calcifications can be seen as focal areas of increase echogenicity with shadowing or as a curvilinear echogenic rim which may simulate an outline of fetal head. Giant Lieomyoma with degeneration and necrosis gives areas of Hypoechoic and cystic spaces [3]. Sonohysterogram gives a better visualization of the endometrial cavity than the Transvaginal ultrasonography and may be useful in differentiating a submucosal fibroid and an endometrial polyp. The echogenicity of submucosal fibroid on sonohysterogram can be Hyperechoic, Isoechoic or Hypoechoic and they are usually solitary. Endometrial polyps which usually are Hyperechoic and contain multiple lesions. ON Color flow Doppler studies submucosal fibroids show multiple feeding vessels and a single feeding artery is shown in most of the polyps [4]. CT scan has limited value as an imaging modality in diagnosing uterine fibroids. They are isodense to the uterine myometrium and cannot be differentiate unless they are forming a contour deformity, calcified or necrotic [2]. MRI is helpful in defining the uterine anatomy, diagnosing and planning the surgery. The normal uterus has three distinct zones in T2W studies. Endometrium is hyperintense, where as the myometrium shows intermediate signal intensity [2]. The junctional zone is seen as a hypointense stripe in between the endometrium and the myometrium. Lieomyomas are best seen on T2w images and can depict smaller lesions as small as .5cm. They appear as solitary or multiple round well defined masses which are homogenously hypointense relative to the myometrium. On T1w sequences fibroids are isointense to the myometrium. These fibroids will depict heterogenous signal intensity when they undergo degeneration and show variable signal characteristics. With intravenous contrast enhanced studies they will enhance similar to or less than the surrounding myometrium in both CT and MRI [2]. Lieomyosarcomas of the uterus can arise as malignant transformation of a Lieomyoma or de novo from myometrium. the appearance is similar to that of rapidly growing or degenerating Lieomyoma except when there is evidence local invasion to blood vessels, lymphatic, and contiguous pelvic structures or distant metastasis. They usually present as massive uterine enlargement with central necrosis and hemorrhage [3, 5]. Free fluid in this case could be due to previously diagnosed renal disease.