Doctors can usually make a diagnosis by looking at the cyst. Your doctor may also scrape off skin cells and examine them under a microscope or take a skin sample biopsy for detailed analysis in the laboratory. Epidermoid cysts look like sebaceous cysts, but they're different. True epidermoid cysts result from damage to hair follicles or the outer layer of skin epidermis. You can usually leave a cyst alone if it doesn't cause discomfort or cosmetic problems. If you seek treatment, talk with your doctor about these options:.
But sebaceous cysts — slow-growing bumps under the skin that can appear on the ears, scalp, face, torso, back, or groin area — are typically harmless. And while they can be irritating or unsightly , they are not cancerous. These dome-shaped cysts can be pea-sized, or grow to a few inches or larger. If you touch them, you should be able to move them around. They often have a central small black dot, or punctum, through which sebum accumulates.