Clinical Significance of Incidental Focal Â¹â¸F-FDG Uptake in the Spinal Cord of Patients with Cancer

Lim, Chae Hong; Hyun, Seung Hyup; Moon, Seung Hwan; Cho, Young Seok; Choe, Yearn Seong; Lee, Kyung Han; Kim, Byung Tae; Choi, Joon Young

Abstract

PURPOSE
We investigated the incidence, location, and clinical significance of focal ¹â¸F-FDG uptake of the spinal cord in patients with cancer.
METHODS
We reviewed the medical records of 22,937 consecutive adult patients with known or suspicious malignancy who underwent ¹â¸F-FDG PET/CT. PET/CT scans with incidental focal spinal cord uptake were selected and retrospectively reviewed to determine the presence, location, number, and maximum standardized uptake value (SUV(max)) of any focal hypermetabolic lesions of the spinal cord. In subjects with focal spinal uptake, clinical characteristics and clinical follow-up results, including follow-up PET/CT, were reviewed.
RESULTS
Incidental focal spinal cord uptake was observed in 69 of 22,937 adult patients (incidence = 0.3%; M:F = 31:38; age, 55.8 ± 14.7 years). Seventy-eight focal hypermetabolic lesions on spinal cord in the PET/CT scans of the 69 study subjects were analyzed. The most common sites of focal spinal cord uptake were the T12 vertebra (47/78; 60.3%) and L1 vertebra (20/78; 25.6%). Multifocal cord uptake was found in 8 of 69 patients (11.6%). The average SUV(max) for cord uptake was 2.5 ± 0.5 (range, 1.4âˆ¼3.9). There was no clinical or imaging evidence of abnormalities in the spinal cord, both at the time of PET/CT and during clinical follow-up.
CONCLUSIONS
Although incidental focal ¹â¸F-FDG uptake of the spinal cord is rare in patients with cancer, it may be physiological or benign, but it should not be considered as malignant involvement. Common sites for the uptake were in the T12 and L1 spine levels.