PET/CT Integrated With CT Colonography in Preoperative Obstructive Colorectal Cancer by Incomplete Optical...

Area of Science:

• Oncology
• Radiology
• Gastroenterology

Background:

• Obstructive colorectal cancer (CRC) diagnosis can be challenging.
• Optical colonoscopy may be incomplete due to obstructive masses.
• Accurate preoperative staging is crucial for effective CRC management.

Purpose of the Study:

• To assess if integrating whole-body positron emission tomography/computed tomography with CT colonography (PET/CTC) enhances preoperative diagnosis of obstructive CRC.
• To evaluate the efficacy of PET/CTC in staging CRC and identifying synchronous tumors and metastases.

Main Methods:

• Prospective study of 47 patients with obstructive CRC diagnosed via optical colonoscopy.
• PET/CTC performed using CO2 insufflation via a Foley catheter.
• Histological confirmation of all findings, with polyps ≥10 mm considered high risk.

Main Results:

• PET/CTC detected all colorectal tumors, showing significant FDG uptake.
• All 12 polyps ≥10 mm demonstrated FDG uptake; only one smaller polyp was PET-detectable.
• PET/CTC achieved 100% sensitivity and specificity for liver metastases, outperforming CT colonography (CTC) alone for lymph node staging.

Conclusions:

• PET/CTC is a reliable method for staging colorectal cancer and detecting synchronous tumors.
• The technique shows potential for excluding larger polyps (≥10 mm) with high malignancy risk.
• PET/CTC's utility in identifying small polyps is limited.