Background: Several studies on 18F-FDG-PET/CT have investigated the prognostic role of
this imaging modality in different tumors after treatment. Nevertheless, its role in restaging patients
with recurrent CM still needs to be defined.
Objective: The aim of this retrospective multicenter study was to evaluate the clinical and prognostic
impact of 18F-FDG-PET/CT on the restaging process of cutaneous melanoma (CM) after surgery in
patients with suspected distant recurrent disease or suspected metastatic progression disease.
Materials and Methods: 74 patients surgically treated for CM underwent 18F-FDG-PET/CT for suspected
distant recurrent disease or suspected metastatic progression disease. The diagnostic accuracy of
visually interpreted 18F-FDG-PET/CT was obtained by considering histology (n=21 patients), other
diagnostic imaging modalities performed within 2 months of PET/CT (CT in 52/74 patients and
Whole-Body MRI in 18/74 patients) and clinical follow-up (n=74 patients) for at least 24 months containing
all the clinical and diagnostic information useful for the PET performance assessment and outcome.
Progression-free survival (PFS) and overall survival (OS) were assessed by using the Kaplan-
Meier method. The risk of progression (Hazard Ratio-HR) was computed by the Cox regression analysis.
Results: Suspicion of recurrent CM was confirmed in 24/27 patients with a positive 18F-FDG-PET/CT
scan. Overall, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy
of 18F-FDG-PET/CT were 82%, 93%, 88%, 89%, and 89%, respectively, with area under the
curve being 0.87 (95%IC 0.78-0.97; p<0.05). 18F-FDG-PET/CT findings significantly influenced the
therapeutic management in 18 patients (modifying therapy in 10 patients; guiding surgery in 8 patients).
After 2 years of follow-up, PFS was significantly longer in patients with a negative vs. a positive
18F-FDG-PET/CT scan (90% vs 46%, p<0.05; Fig. 1). Moreover, a negative scan was associated
with a significantly longer OS than a positive one (76% vs 39% after 2 years, p<0.05; Fig. 2). In addition,
a positive 18F-FDG-PET/CT scan was associated with an increased risk of disease progression
Conclusion: 18F-FDG-PET/CT showed a valuable diagnostic performance in patients with suspicion of
recurrent CM. This imaging modality might have an important prognostic value in predicting the survival
outcomes, assessing the risk of disease progression, and guiding treatment decision making.