CT scans just don't show worms and parasites. I was full of them, some 12 inches long, liver, colon, everywhere, and nothing showed up. Forget stool tests, they're useless too. The most important is how you feel. If you feel relatively healthy, stop worrying. Keep doing your parasite cleanse. But keep in mind that a single parasite cleanse won't get rid of it for good. You need to understand why those bugs took over in the first place. Improve your diet, rebuild digestion, eradicate the bugs, take care of your liver and restore good flora to keep them in check.
If you're really worried about your cyst, try castor oil packs daily for one hour over the liver area. It has amazing properties, such as healing a damaged liver, increasing lymphatic flow, being antiparasitic, and many have effectively shrink tumors and cysts by applying those alone.