The colloid cyst is benign in most cases; there is also a ruptured blood vessel near-by caused this cyst to fill with blood and expand causing pain.
The bleeding and pain usually stop within few days [depending of the size] leaving semi–solid cyst [complex type] filled with the dried blood and necrotic tissue.
Early treatment of small cyst [2-3cm size] includes aspiration of the content, but if cyst refills the PEI treatment can be used.
If cyst is large, rapidly expanding or it causes compression side effects, surgery may be needed.