The value of skeletal standardized uptake values obtained by quantitative single-photon emission computed...

The aim of this study was to explore the value of skeletal standardized uptake value (SUV) obtained by quantitative single-photon emission computed tomography-computed tomography (SPECT/CT) in differential diagnosis of bone metastases from benign lesions.

Retrospective analysis has been conducted to 51 patients with extraskeletal malignant tumors who underwent whole-body bone scan with quantitative SPECT/CT imaging, and there are no more than three hotspots that were visually detected in the SPECT/CT imaging range. Fifty-one patients were enrolled, including 28 men and 23 women with an average age of 58.8 ± 9.5 (37-77) years. A total of 88 hotspots, including 40 benign lesions and 48 metastatic lesions, and corresponding normal sites were obtained. The region of interest (ROI) of the hotspots was sketched. The ROI of the normal bone of the spinal vertebral body adjacent to the lesions or normal bone of the symmetric side of the lesions of other locations was delineated to obtain the maximum SUV (SUVmax) and the average SUV (SUVave).

The SUVmax value of all lesions was 20.73 ± 14.01 (3.90-92.61), and the SUVmax value of the corresponding normal parts was 5.88 ± 2.36 (2.08-12.52). The difference between the two groups was statistically significant (t = 10.343, P < 0.01). The SUVave of all lesions was 8.42 ± 4.81 (37-77), and the SUVave of the corresponding normal sites was 3.10 ± 1.51 (0.65-7.54). The difference between the two groups was statistically significant (t = 11.342, P < 0.01). The SUVmax of metastases was 24.77 ± 16.32 (3.90-92.61), and the SUVmax of benign lesions was 15.89 ± 8.51 (4.68-42.32). The difference between the two groups was statistically significant (t = 3.273, P = 0.002). The SUVave of metastases was 9.09 ± 5.59 (0.81-29.08), and the SUVave of benign lesions was 7.61 ± 3.57 (1.66-17.48). There was no significant difference between the two groups (t = 1.44, P = 0.154). The area under the curve (AUC) values of the SUVmax curves was greater than that of the SUVave curve. AUCs of the SUVmax and SUVave were 0.687 (P = 0.03) and 0.576 (P = 0.223), respectively. SUVmax had greater accuracy for discriminating bone metastasis from benign lesions. Hotspots of the patients with malignant neoplasms in bone SPECT/CT may be discriminated using SUVmax with certain accuracy, and the optimal cutoff value was 17.705.

The SUVmax of bone metastases was significantly larger than that of benign lesions, and there was no significant difference in SUVave between the two groups. Therefore, the SUVmax has a certain value for the differential diagnosis of metastases from benign lesions.