| Theme |
Recent advances in the diagnostic imaging and the treatment of liver metastates from colorectal cancer |
| Title |
Diagnosis of liver metastasis in relation to colorectal cancer through diagnostic imaging |
| Author |
Shinpei Ogawa |
Department of Surgery II, Tokyo Women's Medical University |
| Author |
Miya Yano |
Department of Surgery II, Tokyo Women's Medical University |
| Author |
Michio Itabashi |
Department of Surgery II, Tokyo Women's Medical University |
| Author |
Shingo Kameoka |
Department of Surgery II, Tokyo Women's Medical University |
| [ Summary ] |
Imaging characteristics of liver metastasis related to colorectal cancer obtained from different image modalities and the keys to proper diagnosis for correct choice of therapeutic modality are described. Ultrasonography (US) revealed that bull's eye patterns, cluster signs and calcification were common forms of liver metastasis from colorectal cancer. Computed tomography (CT) showed that X-ray absorption was low at the center of the tumor while it was higher at the periphery of the tumor. X-ray absorption at the metastatic liver lesion was low on CT arterial portography (CTAP), where the region of portal blood flow deficit was located. Metastatic liver lesions appeared as high signal intensity lesions where ferumoxides were not taken up on superparamagnetic iron oxide-magnetic resonance imaging (SPIO-MRI).
Both CT and US are effective in screening for liver metastasis, however they have some limitaions in diagnosing liver micro-metastatic lesions. CTAP is the most effective means for diagnosing liver micro-metastatic lesions, however a large number of false positive results were reported, and the lesions may appear larger than actual tumor size. CTAP was therefore carefully performed. SPIO-MRI is a non-invasive means, which is almost equally effective in diagnosing the presence of metastatic liver lesions as CTAP and accurately measures the diameter of the tumor. We therefore concluded that SPIO-MRI adds to the correct choices for therapeutic modalities. |