Which statement best describes a lipoma?

• A. Lipoma — encapsulated fat
• B. Epidermoid cyst — encapsulated fat
• C. Pilonidal cyst — encapsulated fat
• D. Carbuncle — encapsulated fat

Answer: (A)

A lipoma is a benign tumor of fat that typically forms a soft, mobile, painless subcutaneous nodule and is enclosed by a fibrous capsule. This encapsulation is a key feature, signaling a discrete fat mass rather than a hollow cyst or an infectious process. The statement describes lipoma as encapsulated fat, which fits its histology—mature adipocytes organized in a well-defined, encapsulated mass. The other terms listed are different kinds of lesions: epidermoid cysts contain keratin and are lined by squamous epithelium, pilonidal cysts are a sinus tract with hair and debris, and carbuncles are clusters of infected hair follicles. None of those are simply encapsulated fat masses, so the encapsulated-fat description best matches a lipoma.