Both PET/CT and 3T whole-body MRI appear to provide acceptable accuracy and comparable efficacy for non–small cell lung cancer (NSCLC) staging, but for M-stage determination, each modality has its own advantages, according to a study in the August issue of Radiology.
Chin A. Yi, MD, from the department of radiology and Center for Imaging Science at the Samsung Medical Center and the Sungkyunkwan University School of Medicine in Seoul, South Korea, and colleagues aimed to prospectively compare the diagnostic efficacies of integrated PET/CT and 3T whole-body MRI for determining TNM stages in NSCLC.
The study included 165 patients (125 men; mean age, 61 years) with NSCLC, who underwent both unenhanced PET/CT and whole-body MRI, according to the researchers. Pathologic findings for T (123) and N (150) staging and pathologic or follow-up imaging findings (154) for M staging were reference standards.
The investigators compared the efficacies of PET/CT and whole-body MRI for lung cancer staging by using the McNemar test.
Yi and colleagues found that the primary tumors, detected in 123 patients, were correctly staged in 101 patients (82 percent) at PET/CT and in 106 patients (86 percent) at whole-body MRI.
According to the researchers, N stages (150 patients) were correctly determined in 105 patients (70 percent) at PET/CT and in 102 patients (68 percent) at whole-body MRI.
The authors wrote that 31of 154 patients (20 percent) had metastatic lesions. Accuracy for detecting metastases was 86 percent (133 of 154 patients) at PET/CT, and that at whole-body MRI was 86 percent (132 of 154 patients), according to the investigators.
Although the differences were not statistically significant, Yi and colleagues said that the whole-body MRI was more useful for detecting brain and hepatic metastases, whereas PET/CT was more useful for detecting lymph node and soft-tissue metastases.