Cysts develop from multiple factors including trauma, infection, clogged or damaged sebaceous (oil) glands, and foreign bodies embedded in skin. Different cyst types have specific formation mechanisms but all involve trapped material beneath the skin surface.

Common types include epidermal cysts (trapped skin cells), sebaceous cysts (from damaged oil glands), pilar cysts (firm, flesh-colored bumps on scalp), and acne cysts (large, deep, pus-filled lesions that resemble boils). Each type has distinct characteristics and locations.

Cysts are noncancerous and typically not dangerous. However, infected or inflamed cysts can cause pain, redness, and swelling. Rarely, certain cyst types may indicate underlying conditions. Professional evaluation confirms diagnosis and rules out concerning lesions.

Removal is considered for cosmetic reasons when cysts are visible or bothersome, when they cause pain or discomfort, if they become repeatedly infected, or if they interfere with function due to location. Removal is not medically necessary for asymptomatic cysts.

Complete surgical excision with removal of the entire cyst wall minimizes recurrence risk. If the cyst wall remains, the cyst may refill and return. Kenalog injection treats inflammation but does not prevent recurrence. New cysts can develop elsewhere.