title: An unusual rectal mass.
authors: Department of Gastroenterology and Hepatology, St. Antonius Hospital, Nieuwegein, The Netherlands.
authors: Claudia K
authors: CK
authors: Tigchelaar
authors: Department of Pathology, University Medical Center Utrecht, Utrecht, The Netherlands; Department of Pathology, St. Antonius Hospital Nieuwegein, Nieuwegein, The Netherlands.
authors: Lodewijk A A
authors: LAA
authors: Brosens
authors: Department of Pathology, St. Antonius Hospital Nieuwegein, Nieuwegein, The Netherlands.
authors: Cees A
authors: CA
authors: Seldenrijk
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001706:Biopsy; D003113:Colonoscopy; D003937:Diagnosis, Differential; D018451:Homosexuality, Male; D006801:Humans; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000382:microbiology; D010400:Penicillin G / Q000627:therapeutic use; D011237:Predictive Value of Tests; D011349:Proctitis / Q000382:microbiology; D012002:Rectal Diseases / Q000175:diagnosis* / Q000188:drug therapy / Q000382:microbiology; D012004:Rectal Neoplasms / Q000175:diagnosis*; D013587:Syphilis / Q000175:diagnosis* / Q000188:drug therapy / Q000382:microbiology; D016896:Treatment Outcome; D014210:Treponema pallidum / Q000302:isolation & purification*
chemical_list: D000900:Anti-Bacterial Agents; D010400:Penicillin G