[CT arteriography for evaluation of hepatic metastases from colorectal cancer: diagnostic efficacy of a combination of CT arterial portography and CT arteriography].

The sensitivity of computed tomographic arteriography (CTA) for the detection of hepatic metastases from colorectal cancer was compared with that of computed tomographic arterial portography (CTAP). And the diagnostic efficacy of the combined use of CTAP and CTA (CTAP-CTA) was evaluated for further improvement of detecting the lesions. Both CTAP and CTA were performed sequentially in 71 patients with hepatic metastases from colorectal cancer, of whom 29 patients underwent hepatic resection and 42 patients underwent chemotherapy or clinical observation. CTAP via the superior mesenteric artery was firstly obtained, and CTA via the proper or common hepatic artery followed, employing an interventional CT system, a newly developed angiographic unit combined with a CT scanner. In all metastases, the rate of sensitivity of CTAP, CTA and CTAP-CTA were 93.3%, 93.8% and 98.8%, respectively. In small metastatic lesions of less than 1 cm in diameter, the sensitivity rates of CTAP, CTA and CTAP-CTA were 92.2%, 92.0% and 98.3%, respectively. The difference between the sensitivity of CTAP-CTA and that of CTAP or CTA alone was statistically significant (P < 0.01). In cases of resected metastatic lesion, the sensitivity rates of conventional CT (con.CT), CTAP, CTA and CTAP-CTA were 77.0%, 86.9 %, 90.2% and 91.8% respectively. The difference between the sensitivity of CTAP-CTA and that of con. CT was statistically significant (P < 0.01). Subsequently, the addition of CTA to CTAP was useful in 16 of 71 patients (22.5%). In conclusion, CTAP-CTA showed higher diagnostic efficacy than CTAP alone. Thus CTAP-CTA is recommended for precise pretherapeutic evaluation of hepatic metastases from colorectal cancer.