FOLH1 and neoplasm: These data are similar to previous reports in which it was revealed that more than 90% of primary PCa show moderate to high PSMA expression levels by68Ga-PSMA-PET.31It is known that less than 10% of primary cancer tumors may not overexpress PSMA28and that false-negative scans may occur if PCa is poorly differentiated or displays neuroendocrine aberrations.18Furthermore, low PSMA expression caused by tumor heterogeneity32might be responsible for occasional false-negative PET/CT results.