Comprehensive role of fluorine-18-labeled fluorodeoxyglucose PET/computed tomography across the disease course of primary malignant melanoma of the esophagus.

Abstract

This study aimed to evaluate the clinical value of fluorine-18-labeled fluorodeoxyglucose (18F-FDG) PET/computed tomography (CT) in managing primary malignant melanoma of the esophagus (PMME). Seventy patients with pathologically confirmed PMME between September 2011 and June 2025 were retrospectively analyzed. The diagnostic performance of 18F-FDG PET/CT was analyzed for evaluating primary tumors, lymph nodes, recurrence, metastasis, and its role in predicting treatment response. Among 20 patients who underwent preoperative evaluation, no significant differences in 18F-FDG uptake or tumor wall thickness were observed between T1 and T2/T3 tumors (all P > 0.05). Lesion-based analysis revealed that the area under the receiver operating characteristic curve for lymph node evaluation was 0.923 for 18F-FDG PET/CT and 0.738 for contrast-enhanced CT, with sensitivities of 82.6 and 47.8%, and specificities of 98.0 and 97.0%, respectively. Among 25 patients who received nonsurgical treatment, significant differences were found in maximum standardized uptake value, metabolic tumor volume (MTV), total lesion glycolysis (TLG), and tumor wall thickness between responders and nonresponders (all P < 0.05). Multivariate analysis identified TLG as an independent predictor of treatment response (odds ratio = 0.950, P = 0.025). In 50 patients evaluated for distant metastases and postoperative recurrence, additional findings from 18F-FDG PET/CT led to significant management changes in 14.0% of patients (7/50). 18F-FDG PET/CT is highly effective for evaluating lymph nodes and distant metastases in PMME, and facilitates early identification of patients likely to respond to treatment. It may serve as a valuable tool for staging, response prediction, and follow-up of patients with PMME.