Dermatology issues can include cysts, which are four-letter medical terms for a closed sac or capsule containing fluid or semisolid material. Cysts can be caused by a variety of factors, including infection, inflammation, trauma, or blockage of a gland or duct. They can occur anywhere on the body and can range in size from microscopic to several centimeters in diameter. Treatment for cysts depends on the type and severity of the CYST, but may include draining, surgical removal, or medication.