Can pilonidal cyst be cancerous?

Very rare: It would be very rare for a pilonidal cyst to become cancerous. Very rarely, long term repeated infections over a very long time can result in a rare cancerous condition.

Very rare: There is a vary rare occurrence of squamous cell cancer is long term chronic wounds (> 10 years). It is something to be aware about, but very rare indeed. The point is, yes it can happen, but it rarely does happen.

Not typically. : But in very rare cases a chronic inflammation (like from a pilonidal cyst) can result in skin damage which could turn into cancer. Also, you need to be sure it IS a pilonidal cyst and not a can er that is mistaken for a cyst