Abstract
OBJECTIVE: This study aims to explore the clinical value of the combination of (18)F fluorodeoxyglucose ((18)F-FDG) and N-[2-(dimethylamino) ethyl]-(18)F-5-fluoropicolinamide ((18)F-P3BZA) positron emission tomography/computed tomography (PET/CT) in melanoma patients. METHODS: A retrospective study was conducted on 19 melanoma patients who underwent (18)F-FDG and (18)F-P3BZA PET/CT scans at the Nuclear Medicine Department/PET Imaging Center of the Second Xiangya Hospital, Central South University, from March 2022 to March 2024. The diagnostic efficacy of (18)F-FDG, (18)F-P3BZA, and the combination of both for melanoma was compared, and the value of combined imaging for TNM staging and clinical treatment decision-making in melanoma patients was discussed. RESULTS: The sensitivity of (18)F-P3BZA in diagnosing primary lesions of melanoma, all metastases, sentinel lymph node metastases (SLNM), distant lymph node metastases (DLNM), and bone metastases (BM) was 100% (12/12), 71.4% (40/56), 72.4% (21/29), 66.7% (14/21), and 83.3% (5/6), respectively. The corresponding values for (18)F-FDG were 91.7% (11/12), 91.1% (51/56), 86.2% (25/29), 95.2% (20/21), and 100% (6/6), respectively. Combined imaging showed a higher sensitivity in diagnosing SLNM, DLNM, and all metastases than (18)F-P3BZA (χ (2) = 7.105, p = 0.004; χ (2) = 3.860，p = 0.045; χ (2) = 15.604; p < 0.001). In addition, the specificity of (18)F-FDG in diagnosing all metastases, SLNM, DLNM, and BM, was 50.0, 69.2, 56.3, and 100%, respectively, and the corresponding values for (18)F-P3BZA were 81.8, 100, 75.0, and 100%, respectively. Combined imaging improved N and M staging in 31.6% (6/19) of melanoma patients and changed clinical treatment decisions in 26.3% (5/19) of melanoma patients. CONCLUSION: The specificity of (18)F-FDG alone in diagnosing melanoma is low, but it can be combined effectively with (18)F-P3BZA. The combination of (18)F-FDG and (18)F-P3BZA PET/CT can further improve the detection efficiency of lesions, TNM staging, and clinical treatment decisions.