What does 'echofree' ovarian cyst mean?

Cyst: The ultrasound echoes back and the signal like weather radar is disturbed when it hits solids. Echo Lucent is clear and generally a cyst.

Here are some ...: The term - echo-free describes no echo-reflecting material such as new growth or clot or .. but fluid of same nature inside the cyst space suggesting almost next-to-none odd to have cancer; that is good. But, still remember all the medical care is based on indirect evidence resulting from continual collection and analysis of available experience. So is an echo-free cyst.