Differential Diagnosis for a Rapidly Growing Lump
- Single most likely diagnosis
- Hematoma: A collection of blood outside of blood vessels, which can grow rapidly due to continuous bleeding. This is a common cause of rapidly enlarging lumps, especially if there's a history of trauma.
- Other Likely diagnoses
- Abscess: A pocket of pus that can form as a result of infection, which can grow quickly as the infection progresses. Symptoms often include redness, warmth, and tenderness around the lump.
- Lipoma: Although typically slow-growing, some lipomas can grow more rapidly, especially if they are angiolipomas, which have a higher vascular component.
- Sebaceous cyst: While usually slow-growing, sebaceous cysts can become inflamed and appear to grow rapidly due to the accumulation of pus or fluid.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Soft tissue sarcoma: Although rare, these malignant tumors can grow rapidly and are life-threatening if not diagnosed and treated promptly.
- Necrotizing fasciitis: A severe infection of the tissue beneath the skin, which can spread quickly and is fatal if not treated immediately.
- Aneurysm: An abnormal ballooning of a blood vessel that can present as a rapidly growing lump, especially if it's a pseudoaneurysm or if there's an impending rupture.
- Rare diagnoses
- Myxoid tumors (e.g., myxoma, myxoid liposarcoma): These are rare, benign or malignant tumors that can grow rapidly due to their high water content.
- Lymphangioma: A rare, benign tumor of the lymphatic vessels that can grow rapidly, especially if it becomes infected or hemorrhagic.
- Kaposi's sarcoma: A rare, malignant tumor associated with immune suppression (e.g., HIV/AIDS) that can present with rapidly growing lesions.