High Lung Shunt Fraction in Colorectal Liver Tumors Is Associated with Distant Metastasis and Decreased Survival

LSF may be a more robust marker of metastasis than tumor size. Increased LSF secondary to vascular shunting within liver metastasis is an indicator of distant lesions and is associated with decreased survival after SIRT. Intratumoral shunting may provide a conduit for circulating tumor cells to access more remote organs, bypassing filtration by liver parenchyma, and may be an important factor in metastasis from colorectal cancer.