ABSTRACT
CHALLENGING CASE A 74 year old male underwent low anterior resection of the rectum one year previously after preoperative chemotherapy and radiation. Final pathology revealed a yPT2N0M0 lesion. He received post operative chemotherapy as well. In follow up he was noted to have an elevated carcinoembrionic antigen of seven. Digital exam revealed a palpable mass at the finger tip. It was one half circumferential, posteriorly based, involving the left pelvic sidewall and was fixed. Located at five cm from the verge on rigid proctoscopic exam, it was just at the top of the anorectal ring and involved the previous anastomosis. Computed Tomographic (CT) scan of the chest abdomen and pelvis revealed a posteriorly based mass adjacent to the sacrum without boney erosion. It suggested involvement of the left pelvic sidewall. There was a two cm hypodense lesion in segment three of the liver. The chest was clear. Positron Emission Tomography revealed intense uptake in the pelvis and in the hypodense area of the left lobe of the liver noted on CT. Magnetic Resonance Imaging of the pelvis confirmed extension into the pelvic sidewall but did not reveal boney involvement of the sacrum. Colonoscopy cleared the proximal colon. Biopsies confirmed a moderately well differentiated adenocarcinoma.
