Prognostic value of FDG-PET/CT findings in mucosal melanoma of the head and neck treated with carbon ion radiotherapy
摘要
To investigate the prognostic value of 18F-fluorodeoxyglucose positron emission tomography-computed tomography (FDG-PET/CT) in patients with mucosal melanoma of the head and neck (MMHN) treated with carbon ion radiotherapy (CIRT).
MethodsThis single-center retrospective study included patients with MMHN who underwent CIRT and FDG-PET/CT. Correlations between pre-treatment FDG-PET/CT-derived parameters, including the maximum standardized uptake variable (SUVmax), metabolic tumor volume (MTV) with a 50% threshold, total lesion glycolysis (TLG), bone marrow/liver SUVmax and mean standardized uptake variable (SUVmean) ratios, and spleen/liver SUVmax and SUVmean ratios (SLRmax, SLRmean), with clinical parameters and prognosis were statistically analyzed.
ResultsA total of 32 patients with MMHN were enrolled (median age, 72.5 years). The tumor stages were distributed as follows: T3, 17 patients; T4a, 14 patients; T4b, one patient. The median total observation period was 22.6 months, the median overall survival (OS) was 21.6 months, and the median progression-free survival (PFS) was 11.5 months. Thirteen patients (40.6%) died, 10 (31.3%) experienced local recurrence, and 19 (59.4%) had distant metastases during the observation period. The 1 and 3-year survival rates were 78.1% and 62.5%, respectively. FDG-PET/CT showed pronounced positive uptake for all tumors (median SUVmax: 13.8, range 2.7–33.0). SLRmax was high in patients with negative programmed death-ligand 1 expression in the tumor (p = 0.05). PFS was shorter in patients with a high MTV (p = 0.018). In the multivariate analysis, MTV was an independent prognostic factor for PFS (hazard ratio, 2.60; 95% confidence interval, 1.065–6.345; p = 0.036). MTV and TLG were not predictive of OS in the univariate analysis.
ConclusionsFDG-PET/CT showed a strong positive uptake for MMHN. FDG-PET/CT-derived imaging parameters may be significant prognostic biomarkers for predicting tumor progression in patients with MMHN.