Hepatic parenchymal enhancement during triple-phase helical CT: Can it be used to predict which patients with breast cancer will develop hepatic metastases?

PURPOSE: To evaluate the efficacy of hepatic enhancement characteristics fo r identification of patients with breast cancer who are at risk for future hepatic metastases. MATERIALS AND METHODS: Triple-phase helical computed tomography (CT) was pe rformed in 60 patients with known breast cancer without visible hepatic met astases. Peak hepatic attenuation and enhancement, and attenuation and enha ncement at 25 and 30 seconds were obtained. Ratios of hepatic attenuation o r;enhancement at 25 and 30 seconds to peak hepatic attenuation or enhanceme nt were calculated. A Wilcoxon rank sum test was used to compare patients w ith and those without subsequent hepatic metastases. RESULTS: During a mean 18-month follow-up, 18 patients (30%) developed hepa tic metastases. Decreases in peak hepatic attenuation and enhancement and i ncreases in hepatic attenuation and enhancement ratios at 25 and 30 seconds were seen in patients who developed metastases compared with those who did not (P < .05). When corrected for chemotherapy interval, these differences were not statistically significant. Using a threshold value of 0.40 or mor e for the enhancement ratio at 30 seconds resulted in sensitivity of 28%, s pecificity of 92%, and accuracy of 55%. CONCLUSION: Patients with breast cancer who develop subsequent hepatic meta stases have higher relative hepatic arterial perfusion during triple-phase CT; however, after correction for chemotherapy interval, this difference wa s not statistically significant. Threshold values cannot be used reliably t o identify patients who will develop metastases.