“…Overall, there is a growing consensus that ignoring bones and tissue variability of attenuation coefficients in threeor four-class attenuation maps does not significantly impair lesion detectability and, in general, the diagnostic confidence of PET findings. 26,56 In addition, when PET molecular information is being complemented with MRI functional and morphological information, the number of equivocal findings can be substantially reduced, especially in soft-tissue neoplastic involvements typically encountered in prostate cancer, 160 head and neck cancers, 153,[161][162][163] and gynecologic cancer. 164 However, the presence of artifacts in MRAC maps, particularly metal-susceptibility artifacts, can complicate the interpretation of PET findings 56 and even lead to falsepositive or false-negative findings.…”