18F-fluorodeoxyglucose (FDG) PET/CT performed for MCC staging showed elevated FDG uptake (SUVmax 3.3), which was higher than that of the hepatic parenchyma (SUVmean 2.0), corresponding to the previously noted PSMA-avid left inguinal lymph nodes (Figure 2). This evidence concerns the gene FOLH1 and Merkel cell skin cancer.