The clinical impact of camera-based positron emission tomography imaging in patients with recurrent colorectal cancer.
OBJECTIVE
F18-fluorodeoxyglucose (FDG)-positron emission tomography (PET) studies have clinical value in suspected recurrent or metastatic colorectal cancer cases. Because this modality is not accessible for many patients, a camera-based FDG (CB-FDG) coincidence imaging was suggested as an alternative. Although inferior in resolution to a dedicated PET system, it can make FDG studies available to more patients. We assessed the clinical value of CB-FDG in patients with recurrent colorectal cancer.


METHODS
The disease stage and treatment approach in 83 patients were twice determined by an oncologist and a surgeon, first based on the patient's records and blind to CB-FDG findings and then with the inclusion of FDG results in the decision-making analysis.


RESULTS
On a lesion-based analysis, the sensitivity of CB-FDG was 95% and the specificity was 81% compared with 88% and 64%, respectively, for computed tomography. Adding FDG findings led to disease-stage alteration in 47 patients (57%), upstaging in 35 (42%), and downstaging in 12 (15%). FDG localized the tumor sites in 21 of 26 patients (81%) with suspected clinical recurrence and a negative conventional imaging workup. In 8 patients, FDG ruled out viable tumor tissue suggested by other modalities. The oncologist's suggested treatment approach was altered in 54% of the patients and the surgeon altered the decision on operability in 28%.


CONCLUSIONS
CB-FDG assessment has clinical value for both staging and selecting treatment in patients with recurrent colorectal cancer and can be considered an alternative to an nonaccessible dedicated PET system.
Miller
Elka
E
Department of Nuclear Medicine, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel.
Lerman
Hedva
H
Gutman
Mordechai
M
Figer
Arie
A
Livshitz
Genady
G
Even-Sapir
Einat
E
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging*; D019275:Radiopharmaceuticals; D014055:Tomography, Emission-Computed / Q000295:instrumentation*
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18