Abstract
Various forms of hepatic actinomycosis can be observed on the imaging studies. We report here the imaging findings of three cases of hepatic actinomycosis, which presented as a solid mass mimicking a malignant tumor. With respect to their enhancement pattern on the contrast-enhanced CT and MR images, one case showed homogeneous and persistent enhancement throughout three phases, while the other two cases showed variable degrees of delayed enhancement with their own features during the portal and equilibrium phases, suggesting that they have abundant fibrosis at different stages. Also, normal vascular structures traversing the masses were noted in all three cases. One core needle biopsy and two surgical resections were performed, and the masses were pathologically proven to be hepatic actinomycosis. In conclusion, we need to be aware that a hepatic tumor with abundant fibrosis, in which the normal vasculature is traversing, can be diagnosed as hepatic actinomycosis.
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