case_images: PMC6159238_01
case_images: Photograph showing the malignant appearing stricturing sigmoid lesion seen at 25 cm from anal verge taken during colonoscopy.
case_images: bjrcr.20160074.g001.jpg
case_images: PMC6159238_01_bjrcr.20160074.g001.jpg
case_images: f1
case_images: More proximally in the distal sigmoid colon at 25 cm there was a segment of a malignant-looking lesion associated with a stricture (Figure 1).
case_images: (a) CT axial slice through the pelvis showing the thickened distal sigmoid colon with multiple diverticulae (white arrow). The linear hyperdense line on the intraluminal surface represents the poorly demarcated dental prosthesis. (b) MRI axial slice corresponding to the CT image showing an intraluminal low signal, well-defined linear structure corresponding to the dental prosthesis.
case_images: bjrcr.20160074.g002.jpg
case_images: PMC6159238_01_bjrcr.20160074.g002.jpg
case_images: f2
case_images: This demonstrated, at the site of the presumed malignancy in the distal sigmoid colon, a 7 cm segment of circumferential thickening on a background of diverticulosis (Figure 2a).
case_images: Sagittal T2 sequences showing part of the dental plate (white arrow) in the thickened distal sigmoid colon and the rectal tubulovillous adenoma (black arrow).
case_images: bjrcr.20160074.g003.jpg
case_images: PMC6159238_01_bjrcr.20160074.g003.jpg
case_images: f3
case_images: The sigmoid tumour was incidentally included in the MRI scan field owing to proximity to the rectal lesion (Figure 3); however, this did not add any diagnostic value preoperatively.
case_images: (a) Histological specimen showing the section of the distal sigmoid colon presumed to be malignant and the edges of the dental plate. Diverticular out-pouchings can also been seen in this specimen. (b) The recovered partial denture with a single tooth measuring 5 cm in longest length with sharp jagged edges that presumably contributed to its impaction.
case_images: bjrcr.20160074.g004.jpg
case_images: PMC6159238_01_bjrcr.20160074.g004.jpg
case_images: f4
case_images: The ulceration was associated with a 5 cm jagged edged intraluminal dental plate containing a single front upper incisor prosthetic tooth found impacted at this site, with no metallic components (Figure 4a,b).
case_images: The CT scout view shows no radiopaque foreign body.
case_images: bjrcr.20160074.g005.jpg
case_images: PMC6159238_01_bjrcr.20160074.g005.jpg
case_images: f5
case_images: The CT scout view also demonstrates no radiopaque foreign body (Figure 5).