Purpose: According to the German guidelines on colorectal cancer, unenhanced ultrasound is recommended for follow-up. On the other hand, ultrasound and radiology societies specify the use of contrast-enhanced ultrasound for ruling out liver metastases. Studies focusing on the follow-up of cancer patients are lacking. The goal of this multicenter study initiated by the German Ultrasound Society (DEGUM) was to determine the potential benefit of contrast-enhanced ultrasound in the follow-up of patients with colon cancer.
Materials and methods: Follow-up patients with colon cancer (UICC > IIa) were investigated. As scheduled according to the German guidelines, unenhanced ultrasound was performed followed by contrast-enhanced ultrasound. All liver lesions were recorded. In case of additional metastases detected on contrast-enhanced ultrasound, contrast-enhanced CT, MRI or biopsy was performed to confirm additional liver metastases.
Results: A total of 45 liver metastases were detected in 26/290 patients (= 9 %) using unenhanced ultrasound. A further 28 metastases were detected on contrast-enhanced ultrasound in these 26 patients. In 18 patients showing no liver metastases, 40 additional metastases were detected on unenhanced ultrasound. This means that 44 patients with a total of 113 liver metastases were detected on contrast-enhanced ultrasound (p = 0.0006).
Conclusion: Contrast-enhanced ultrasound should be recommended in the follow-up of patients with colon cancer in addition to unenhanced ultrasound - the up-to-date standard.
© Georg Thieme Verlag KG Stuttgart · New York.