A rare case of extraluminal gastrointestinal stromal tumor of the ileum presenting with lower urinary tract symptoms: A case report.

Benign prostatic hyperplasia, bladder outlet obstruction, and overactive bladder are major causes of lower urinary tract symptoms (LUTS). Tumor compression of the urinary bladder resulting in LUTS was clinically observed. Gastrointestinal stromal tumors (GISTs) presenting with LUTS have not been reported before. Herein, we report a patient with extraluminal GIST of the ileum who had LUTS without gastrointestinal symptoms during the clinical course.A 68-year-old man visited the genitourinary outpatient department because of frequent urination with mild dysuria. He also complained of poor appetite, fatigue, and body weight loss of 10 kg over 6 months. A large presacral solid mass lesion compressing the bladder and surrounded by the bowel with gas content was identified through abdominal computed tomography.GIST of the ileum with mesenteric invasion was revealed by pathological examination.Exploratory laparotomy with removal of the pelvic tumor and segmental resection of the ileum was performed.Now, he received adjuvant imatinib target therapy for 1 year with stable condition.Extravesical compression or invasion of the urinary bladder by a pelvic mass lesion is common but is rarely accompanied by GISTs of the ileum. Specific findings identified through imaging should alert the surgeon to this specific entity and prepare thoroughly before surgical intervention.