Staging recurrent metastatic colorectal carcinoma with PET

Area of Science:

• Oncology
• Nuclear Medicine
• Radiology

Background:

• Accurate detection of recurrent colorectal carcinoma is crucial for effective patient management.
• Diagnostic challenges persist in identifying metastatic disease, particularly liver and extrahepatic lesions.

Purpose of the Study:

• To evaluate the accuracy of 18-Fluorodeoxyglucose Positron Emission Tomography (18FDG-PET) in detecting liver metastases from recurrent colorectal carcinoma.
• To compare 18FDG-PET accuracy with computed tomography (CT) and CT portography for liver metastases.
• To assess 18FDG-PET accuracy for extrahepatic metastases compared to CT.
• To determine the impact of 18FDG-PET findings on patient management decisions.

Main Methods:

• Fifty-two patients with suspected recurrent colorectal carcinoma underwent whole-body 18FDG-PET scans.
• Imaging analysis included visual assessment of PET, CT, and CT portography.
• Definitive diagnosis was established through pathology or clinical and radiological follow-up.

Main Results:

• 18FDG-PET demonstrated higher accuracy (92%) in detecting liver metastases compared to CT (78%) and CT portography (80%).
• 18FDG-PET was also more accurate (92%) than CT (71%) for detecting extrahepatic metastases.
• Unsuspected metastases were identified in 17 patients, leading to altered surgical management in 28% of cases.

Conclusions:

• 18FDG-PET is the most accurate noninvasive method for staging recurrent metastatic colorectal carcinoma.
• 18FDG-PET plays a vital role in guiding management decisions for patients with recurrent colorectal cancer.