Thus, whole- liver surveillance remains an important goal after treatment. CT Abdomen CT of the abdomen without and with IV contrast is an accurate method for detecting recurrence of HCC following locoregional therapy, resection, or transplantation. After locoregional therapy, including a precontrast phase, CT is strongly recommended because treatment can render a lesion or perilesional treatment zone high in attenuation (particularly when ethiodized oil is used in embolization), which can confound the interpretation of the hepatic arterial phase [72,73]. Noncontrast CT has a limited role because the detection of recurrent HCC relies primarily on detecting abnormal tumor perfusion. Dual-energy CT can be utilized to derive virtual unenhanced images and/or iodine maps for the same purpose as a dedicated precontrast acquisition. [74]. The National Comprehensive Cancer Network guidelines recommend CT or MRI every 3 to 6 months for 2 years and then every 6 to 12 months after HCC resection, whereas the European Association for the Study of the Liver recommends multiphase CT or MRI to assess response 1 month after resection or locoregional or systemic therapies, followed by one imaging technique every 3 months to complete at least 2 years, and then regular US every 6 months thereafter [75]. FDG-PET/CT Skull Base to Mid-Thigh The utility of FDG-PET/CT in HCC patients has primarily been investigated in the pretreatment setting; little data are available regarding post-treatment monitoring [76]. Because of the need for multiple repeated examinations and efficacy of multiphase contrast-enhanced CT and MRI, FDG-PET/CT is infrequently used for monitoring for HCC recurrence. MR Elastography Abdomen MR elastography has been investigated for the assessment of focal liver lesions with modest success [50]. However, limited spatial resolution and coverage of MR elastography renders it of limited utility for screening and surveillance.
Chronic Liver Disease. Thus, whole- liver surveillance remains an important goal after treatment. CT Abdomen CT of the abdomen without and with IV contrast is an accurate method for detecting recurrence of HCC following locoregional therapy, resection, or transplantation. After locoregional therapy, including a precontrast phase, CT is strongly recommended because treatment can render a lesion or perilesional treatment zone high in attenuation (particularly when ethiodized oil is used in embolization), which can confound the interpretation of the hepatic arterial phase [72,73]. Noncontrast CT has a limited role because the detection of recurrent HCC relies primarily on detecting abnormal tumor perfusion. Dual-energy CT can be utilized to derive virtual unenhanced images and/or iodine maps for the same purpose as a dedicated precontrast acquisition. [74]. The National Comprehensive Cancer Network guidelines recommend CT or MRI every 3 to 6 months for 2 years and then every 6 to 12 months after HCC resection, whereas the European Association for the Study of the Liver recommends multiphase CT or MRI to assess response 1 month after resection or locoregional or systemic therapies, followed by one imaging technique every 3 months to complete at least 2 years, and then regular US every 6 months thereafter [75]. FDG-PET/CT Skull Base to Mid-Thigh The utility of FDG-PET/CT in HCC patients has primarily been investigated in the pretreatment setting; little data are available regarding post-treatment monitoring [76]. Because of the need for multiple repeated examinations and efficacy of multiphase contrast-enhanced CT and MRI, FDG-PET/CT is infrequently used for monitoring for HCC recurrence. MR Elastography Abdomen MR elastography has been investigated for the assessment of focal liver lesions with modest success [50]. However, limited spatial resolution and coverage of MR elastography renders it of limited utility for screening and surveillance.