When a biopsy is performed to diagnose or rule out malignancy in indeterminate lesions, the overall technical success rate under grayscale US guidance is 74%, which can be increased to 100% under CEUS guidance [21,22]. The percentage of tumor cells in the biopsy sample is greater with a higher number of collected biopsy samples [23]. Furthermore, for lesions not seen on grayscale US, the success rate for CEUS-guided biopsy can be as high as 88% to 96% [24,25]. US fusion with CT or MRI, can be used for percutaneous biopsy of lesions with poor sonographic conspicuity, with a 96% technical success rate [25]. Lesions that are isointense on CT can also present a challenge for CT-guided biopsy; however, use of anatomic landmarks or IV contrast can achieve an accuracy of 96% to 98% [26]. The image-guided biopsies carry a risk of postbiopsy bleeding that may be as high as 9% to 12%, particularly with hypervascular lesions [27,28]. In addition, a small risk of needle-track seeding exists. In patients with HCC, the rate of seeding is 0.1% to 0.7% [52-54]. RBC Scan Abdomen and Pelvis There is no relevant literature to support the use of a Tc-99m RBC scan in this clinical scenario. Liver Spleen Scan There is no relevant literature to support the use of a Tc-99m sulfur colloid scan in this clinical scenario. US Abdomen Grayscale US is able to provide correct diagnosis in 68% of liver lesions [9]. For differentiation between malignant and benign lesions, US is correct in 86% of cases [9]. US Abdomen with Contrast In noncirrhotic patients, the hypoechoic pattern in portal and sinusoidal phase (rapid wash-out) or the markedly hypoechoic or anechoic pattern in sinusoidal phase (marked late wash-out) showed a sensitivity, specificity, and accuracy of 97%, 100%, and 98%, respectively, for the diagnosis of malignancy [37].
Liver Lesion Initial Characterization. When a biopsy is performed to diagnose or rule out malignancy in indeterminate lesions, the overall technical success rate under grayscale US guidance is 74%, which can be increased to 100% under CEUS guidance [21,22]. The percentage of tumor cells in the biopsy sample is greater with a higher number of collected biopsy samples [23]. Furthermore, for lesions not seen on grayscale US, the success rate for CEUS-guided biopsy can be as high as 88% to 96% [24,25]. US fusion with CT or MRI, can be used for percutaneous biopsy of lesions with poor sonographic conspicuity, with a 96% technical success rate [25]. Lesions that are isointense on CT can also present a challenge for CT-guided biopsy; however, use of anatomic landmarks or IV contrast can achieve an accuracy of 96% to 98% [26]. The image-guided biopsies carry a risk of postbiopsy bleeding that may be as high as 9% to 12%, particularly with hypervascular lesions [27,28]. In addition, a small risk of needle-track seeding exists. In patients with HCC, the rate of seeding is 0.1% to 0.7% [52-54]. RBC Scan Abdomen and Pelvis There is no relevant literature to support the use of a Tc-99m RBC scan in this clinical scenario. Liver Spleen Scan There is no relevant literature to support the use of a Tc-99m sulfur colloid scan in this clinical scenario. US Abdomen Grayscale US is able to provide correct diagnosis in 68% of liver lesions [9]. For differentiation between malignant and benign lesions, US is correct in 86% of cases [9]. US Abdomen with Contrast In noncirrhotic patients, the hypoechoic pattern in portal and sinusoidal phase (rapid wash-out) or the markedly hypoechoic or anechoic pattern in sinusoidal phase (marked late wash-out) showed a sensitivity, specificity, and accuracy of 97%, 100%, and 98%, respectively, for the diagnosis of malignancy [37].