What is the diagnosis of an unknown subcutaneous (SC) mass?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: May 14, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

Differential Diagnosis for Unknown SC Mass

  • Single most likely diagnosis
    • Lipoma: This is the most common benign soft tissue tumor, often presenting as a slow-growing, painless mass in the subcutaneous tissue.
  • Other Likely diagnoses
    • Cyst (epidermoid, sebaceous, or dermatoid): These are common benign lesions that can present as a lump under the skin.
    • Abscess or infected cyst: An abscess is a collection of pus that can cause a painful lump, while an infected cyst can also present as a painful mass.
    • Hematoma: A collection of blood outside of blood vessels, which can occur due to trauma or bleeding disorders.
    • Soft tissue sarcoma (e.g., liposarcoma): Although less common, these malignant tumors can present as a growing mass in the subcutaneous tissue.
  • Do Not Miss diagnoses
    • Metastatic tumor: Although rare, a subcutaneous mass can be a metastasis from a primary cancer elsewhere in the body, such as the breast, lung, or gastrointestinal tract.
    • Inflammatory or infectious process (e.g., cellulitis, erythema nodosum): These conditions can cause a painful, tender mass and require prompt treatment.
    • Lymphoma (cutaneous T-cell lymphoma): A type of cancer that can present with skin lesions or masses.
  • Rare diagnoses
    • Neurofibroma: A benign tumor of the nerve tissue, which can present as a soft, fleshy mass.
    • Granuloma (e.g., foreign body granuloma): A rare, benign lesion that can occur in response to a foreign substance.
    • Panniculitis (e.g., erythema nodosum, Weber-Christian disease): Inflammatory conditions that can cause painful, tender masses in the subcutaneous tissue.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.