PET Improves Management of Patients With Suspected Colorectal Cancer Recurrence
 

TITLE: FDG-PET Improves the Management of Patients With Suspected Recurrence of Colorectal Cancer.

REF: Simo M, Lomen F: Nucl Med Commun 2002; 23 (October): 975-982

BACKGROUND: 40% of patients who have undergone their first surgery for colorectal cancer present with suspected recurrence within the first 2 years of follow-up. Anatomic imaging modalities have limited sensitivity and specificity, especially due to the distorted anatomy after surgery and radiation therapy.

PATIENTS: 120 patients with suspected colorectal cancer recurrence were studied with FDG PET.

FINDINGS: 58 pts were referred to PET due to rising CEA levels. 31 patients were referred due to inconclusive conventional imaging. 25 patients had known recurrence and were referred to PET for pre-surgical assessment. 6 pts were referred due to abdominal pain. A MAJOR MANAGEMENT CHANGE was defined as when medical treatment was changed to surgical, surgical treatment to medical or to no treatment. Of the 58 patients referred to PET due to rising CEA levels, PET led to a major management change in 34(58%). Of the 31 patients referred due to inconclusive conventional imaging, PET led to a major management change in 14 (45%). Of the 25 referred for pre-surgical evaluation, PET led to a major management change in 8 patients (32%). Overall, PET resulted in a major management change in 58/120 patients (48%).

CONCLUSION: FDG PET results in more appropriate therapy in nearly half of patients with suspected recurrence of colorectal cancer who are referred to PET.

COMMENT: it is not clear how many patients with suspected recurrence of colorectal cancer are not referred to PET, and why they are not referred. This study strongly suggests that ALL patients with suspected recurrent colorectal cancer get an FDG PET scan. A major management change of 48% certainly is clinically significant. Both patients who are considered inoperable by conventional imaging, and patients considered operative candidates by conventional imaging can have their management changed due to FDG PET imaging.