Usefulness of CTAP in the diagnosis of hepatic tumors. Comparison with helical-CT in tumor detection, especially tumors under 1 cm in diameter

We studied 24 candidates for hepatectomy with CTAP and helical CT. According to size, we classified all nodules detected with CTAP into two groups (over and under 1 cm in diameter of tumor size). CTAP detected 101 nodules over 1 cm in diameter, whereas helical-CT detected 36 nodules (35.6%). CTAP detected 20 nodules under 1 cm in diameter, whereas helical-CT detected only 4 nodules (20%). Five patients, 3 with HCC and 2 with metastases, were judged to have no indications for hepatectomy. In these 5 cases, CTAP detected 63 nodules of which 47 were over 1 cm in diameter and 16 under 1 cm in diameter. On the other hand, helical-CT detected 13 nodules (27.7%) over and 4 nodules (25%) under 1 cm in diameter. CTAP was more sensitive for the detection of nodules under 1 cm in diameter than helical-CT. The 3 cases with HCC and the 2 with metastases judged to have no indication for hepatectomy after CTAP represent a rather high ratio. In these cases, helical-CT was not sufficient for either diagnosis or decision making regarding operability. We consider CTAP to be essential in the study of hepatic tumors. (author)