1. F/46 C/C polyp in the sigmoid colon

2. V/S BP 120/80 mmHg HR 84/min ROS melena/hematochezia (-/-) bowel habit change (-) bearing down sensation PMHx. hemorrhoidectomy, 14 YA

3. Digital rectal examination: normal CA 125 : normal Cervicovaginal specimen : normal

4. CT submucosal mass lesion at the anterior portion of rectum lymphadenopathy, 1.2 x 0.5 cm, the left mesentery at the kidney level no mass lesion in the liver and other solid organs in the abdomen ascites (-) lung and bone : within normal limits

6. Colonoscopy nodular elevated lesion at AV 12cm 4-5cm sized elevated lesion covering mucosa : normal at the margin hyperemic and nodular mucosa at the center hard in consistency Impression) #1. lymphoma #2. invasion of gynecologic malignancy #3. polyp

8. Submucosal tumor ?Extrinsic compression ?

9. Differential diagnosis of rectal submucosal tumor Non-neoplastic lesionNeoplastic lesion

10. Differential diagnosis of rectal submucosal tumor Non-neoplastic lesionNeoplastic lesion Intramural originExtramural origin Endometriosis Vascular lesions Cystic lesions Hematoma

11. Endometriosis Onset : child bearing age Site : Rectosigmoid area (96%), appendix, ileum Symptom : asymptomatic localized tenderness, low back pain intermittent abdominal pain, consipation hematochezia (rare) - usually not related to menstrual cycle Diagnosis : Clinical suspicion – IBS Colonoscopy and biopsy CT : well enhancing mass

12. Differential diagnosis of rectal submucosal tumor Non-neoplastic lesionNeoplastic lesion Intramural originExtramural origin Lipoma Carcinoid tumor Hemangioma GIST Lymphoma Other primary tumors Metastatic tumor Direct invasion of extracolonic tumor

13. Lymphoma Primary lymphoma of intestine Stomach > small intestine > large intestine Lymphoma of large intestine mostly non-Hodgkin B-cell lymphoma ileocecal area – rectosigmoid region Symptom : non-specific bleeding, obstruction Morphologic manifestation : fungating mass, infiltration, ulcer, SMT

14. Impression 1. Endometriosis 2. Lymphoma