Outcome of small liver nodules detected by computed tomographic angiography in patients with hepatocellular carcinoma

Purpose Hepatic lesions identified by computed tomography (CT) during arterial portography (CTAP) or CT hepatic arteriography (CTHA) in hepatocellular carcinoma (HCC) patients are sometimes too small to be diagnosed as HCC. We undertook this cohort study to assess whether these small lesions are actually HCC, and to clarify the effectiveness of these imaging examinations in a clinical setting. Methods We assessed the characteristics of 74 tiny lesions detected by CTAP and/or CTHA, but not by CT in 67 patients. Results Seven out of 10 nodules were histologically confirmed as HCC and 18 out of 64 lesions increased in size and showed typical findings of HCC during the follow-up period. Multivariate analysis revealed that the size of the main tumor (>30 mm in diameter) was associated with the presence of tiny additional HCC lesions ( P = 0.002). Conclusions These findings indicate that CTAP and CTHA are recommended for determining the stage of HCC, especially when the HCC nodule is larger than 30 mm in diameter.