Double colorectal cancer only diagnosed by computed tomographic colonography

Area of Science:

• Gastroenterology
• Radiology
• Surgical Oncology

Background:

• Obstructive colorectal cancer presents diagnostic challenges for evaluating the proximal colon using standard optical colonoscopy.
• Accurate preoperative staging and identification of synchronous lesions are critical for effective surgical management.

Observation:

• A 58-year-old woman with rectal bleeding and diarrhea was diagnosed with rectal cancer.
• Slim optical colonoscopy revealed an obstructive tumor but could not visualize the proximal colon.
• Computed tomographic (CT) colonography was performed to assess the proximal colon.

Findings:

• CT colonography identified a synchronous protruded lesion proximal to the obstruction.
• Three-dimensional endoluminal 'fly-through' images facilitated diagnosis of synchronous double colorectal cancer.
• Preoperative clinical staging was determined using CT colonography data.

Implications:

• CT colonography is a valuable tool for evaluating the proximal side of obstructive colorectal cancers.
• This imaging modality aids in the detection of synchronous colorectal neoplasms.
• Accurate preoperative assessment with CT colonography improves surgical planning and patient outcomes.