Small hepatocellular carcinoma: Relationship of signal intensity to histopathologic findings and metal content of the tumor and surrounding hepatic parenchyma

PURPOSE: To investigate the relationship between the metal content of hepatocellular carcinoma (HCC) and the signal intensity pattern on magnetic resonance images. MATERIALS AND METHODS: The signal intensity patterns of 59 HCCs 3 cm in diameter or smaller were correlated with histologic findings and metal content. RESULTS: HCCs with high signal intensity on T1-weighted images demonstrated more steatosis (P = .035) and higher copper content (P = .008) than did surrounding hepatic parenchyma. HCCs with high signal intensity on T2-weighted images demonstrated more clear cells (P = .001) than did surrounding hepatic parenchyma. The higher signal intensities on T1-weighted and T2-weighted images were related to a higher and a lower degree of histologic differentiation, respectively. Multivariate analysis showed that the contrast-to-noise ratio between the HCC and surrounding hepatic parenchyma was affected by intratumoral copper content (P = .0338), zinc content of surrounding hepatic parenchyma (P = .0379), and the degree of histologic differentiation on T1-weighted (P = .0031) and T2-weighted (P = .0062) images. CONCLUSION: The signal intensity of HCC on T1-weighted images is related to the degree of histologic differentiation, intratumoral copper content, and zinc content of surrounding hepatic parenchyma, whereas the signal intensity on T2-weighted images is related to the degree of histologic differentiation.