[Modern imaging for liver metastases from colorectal tumors]

Morphologic and Functional Imaging of Non-Colorectal Liver Metastases

Liver metastases are the most frequent malignant liver lesions. Besides colorectal carcinoma, gastric carcinoma, pancreatic carcinoma, breast cancer, lung cancer, and neuroendocrine tumors are the most common entities that metastasize to the liver. The morphology of these metastases depends on the primary tumor. For morphologic and functional imaging of non-colorectal liver metastases, multiple imaging techniques such as ultrasonography, computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography coupled with CT or MRI are available. This review summarizes morphologic and functional characteristics of different non-colorectal liver metastases.

Metachronous liver metastases and resectability: Fong's score and laparoscopic evaluation

BACKGROUND AND AIMS

The aim of this retrospective study was to establish whether Fong's risk score can predict rate of resectability and whether laparoscopic exploration with ultrasonography can reduce the number of useless laparotomies to any extent.

MATERIAL AND METHODS

Fong's score was calculated for each of the 43 potential resectable patients. We analysed: the relation between score and resectability; the probability of unnecessary laparotomy with respect to each level of score; and which of the five Fong parameters was the most indicative of non-resectability. None of our patients was submitted to preoperative laparoscopic staging.

RESULTS

All patients with Fong's score 0 were submitted to liver resection, whereas only 76.9% with score 1, 58.3% with score 2, and 66.6% with score 3. No patients had score 4 and 5. "CEA level" is the parameter that best predicts the "non-resectability" of metastases. In the subgroup with score 0-1, laparoscopy would have spared 12% of unnecessary laparotomies, whereas in subgroup 2-3 this percentage would have risen to 38.9.

CONCLUSIONS

The above data allowed us to quantify statistically the risk associated with non-resectability of liver metastases in a directly proportional manner as the score progresses.

Ultraschall in der Tumornachsorge

According to the guidelines, ultrasonography (US) is now established as the cross-sectional imaging technique of choice in postoperative care of colorectal carcinoma. Although conventional percutaneous US is inferior to computed tomography (CT) and magnetic resonance imaging (MRI) for detecting hepatic metastases, the application of specific contrast media has significantly increased sensitivity and specificity to 87% and 88%, respectively. The combination of US and CT/MRI achieves the highest detection rates. During follow-up of rectal carcinoma, in up to 20% of locoregional recurrences are diagnosed solely by endorectal sonography and result in repeat resection with curative intention. In noncolorectal carcinoma, US is recommended in the guidelines for following up hepatocellular carcinoma and malignant thyroid disease, but the available data are insufficient to support those recommendations.