Seroma vs. Sebaceous Cyst (Ceroma): Key Differences Explained

Although both present as palpable lumps, seromas and sebaceous cysts (often miscalled "ceromas") differ fundamentally in origin, content, and management.

Feature	Seroma	Sebaceous Cyst
Content	Serous fluid (clear, yellowish)	Sebum (cheesy, keratin-rich)
Origin	Post-surgical, traumatic, or inflammatory dead space	Blocked sebaceous gland duct
Location	Surgical sites, body cavities, potential spaces	Scalp, face, neck, trunk (hair-bearing areas)
Wall	No true epithelial lining (pseudocapsule)	True epithelial-lined capsule
Clinical Course	Often self-resolves; may need aspiration	Persists; can become infected; excised if symptomatic
Association	Surgery, trauma, lymph node dissection	Not trauma-related; may be genetic (e.g., steatocystoma)

Accurate diagnosis (clinical ± ultrasound) guides appropriate management: observation/aspiration for seroma vs. excision for symptomatic cyst.