Extragastrointestinal stromal tumor mimicking a uterine tumor. A rare clinical entity

Abstract

Gastrointestinal stromal tumors are the most common mesenchymal tumors of the gastrointestinal tract. These tumors are present in almost all case mutations of KIT-CD117. When located in different places other than the gastrointestinal tract they are called extragastrointestinal stromal tumors (EGISTs). We present the case of a 70-year old patient with abdominal pain. Computed tomography (C/T) and ultrasound (U/S) indicated the existence of a hypoechoic enlarged 9.6 x 10 cm uterus due to leiomyoma. The clinical condition of the patient deteriorated and obtained the characteristics of an acute abdomen. The patient underwent urgent exploratory laparotomy, which revealed the incidental existence of a large tumorous formation in the pouch of Douglas. A total abdominal hysterectomy, bilateral ovarectomy, omentectomy, and tumor resection from the rectouterine pouch were performed. Histology analysis confirmed the diagnosis of a malignant EGIST. EGISTs are infrequent in pelvis. In our case, pelvic EGIST led to an acute pain symptomatology obtaining characteristics of invasive uterine leiomyosarcoma. Pelvic imaging with classical methods of U/S and C/T may lead to confusion and false diagnosis. To the best of our knowledge, this is the first case report about an EGIST located in the rectouterine pouch of Douglas leading to acute abdomen symptomatology.

Reclassification of Leiomyosarcoma as an Extra-gastrointestinal Stromal Tumor of the Gynecologic Tract

“…Arising from interstitial cells of Cajal, GISTs most commonly occur in the stomach (60%), jejunum/ileum (30%), duodenum (4%-5%), rectum (4%), and colon/appendix (1%-2%) (2). These rare tumors have been described outside the intestinal tract, in the omentum or retroperitoneum (7). EGISTs are also found in gynecologic organs such as the vagina and fallopian tubes; however, there are only 12 other gynecologic cases reported, 3 of which are described in the rectovaginal septum, making this location for an EGIST very unique (Table 1) (1,7-13).…”

“…After performing a literature search using MEDLINE from January 1, 1950 to August 1, 2008 using the search terms ''leiomyoscaroma, GIST, gastrointestinal stromal tumor, EGIST, extra-gastrointestinal stromal tumor, rectovaginal septum, vagina, vulva, perineum, uterus, ovary, and gynecology,'' we found 3 other cases of EGIST arising in the rectovaginal septum that were reported in the English literature (Table 1) (1,(7)(8)(9)(10)(11)(12)(13). To our knowledge, this represents the 13th case of EGIST reported in the gynecologic tract and the fourth case described in the rectovaginal septum.…”

DOG1 immunoreactivity in uterine leiomyosarcomas

“…EGISTs in the gynaecological tract are rare,3 4 20–22 but may be more common than is recognised. As far as we are aware, only two cases of primary uterine EGIST had been reported in the literature, both of which have had molecular confirmation 3 4. Interestingly, in one of these studies, normal uteri used as controls contained CD117 positive Cajal-like mesenchymal cells scattered in the myometrium 3.…”

Extragastrointestinal Stromal Tumor during Pregnacy

“…There are usually mutations in either KIT-CD117 or PDGF (platelet-derived growth factor) with these kind of mesenchymal tumors [9]. 95% of GISTs are found with CD117 somatic mutation.…”