What is the diagnosis for a large back mole with a red rash surrounding it?

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Differential Diagnosis for Large Back Mole with Red Rash Surrounding it

  • Single most likely diagnosis
    • Melanoma: This is the most concerning and likely diagnosis given the description of a large mole with a red rash surrounding it. The ABCDE rule (Asymmetry, Border, Color, Diameter, Evolving) is often used to evaluate suspicious moles, and a red rash could indicate inflammation or regression, which are signs of potential malignancy.
  • Other Likely diagnoses
    • Seborrheic Keratosis with inflammation: This is a common benign skin growth that can become inflamed, leading to a red rash around the lesion.
    • Dermatofibroma: A benign skin growth that can sometimes become inflamed or irritated, causing a red rash.
    • Pyogenic Granuloma: A benign vascular lesion that can appear as a red, bleeding bump, sometimes surrounded by a red rash.
  • Do Not Miss (ddxs that may not be likely, but would be deadly if missed)
    • Merkel Cell Carcinoma: A rare and aggressive skin cancer that can present as a firm, painless nodule or bump, sometimes with a red rash.
    • Angiosarcoma: A rare and aggressive cancer of the blood vessels that can present as a red, bruise-like lesion or rash.
    • Lymphoma (Cutaneous T-Cell Lymphoma): A type of cancer that affects the immune system and can present with skin lesions, including red rashes.
  • Rare diagnoses
    • Kaposi's Sarcoma: A rare cancer that can cause red, purple, or brown lesions on the skin, often associated with immune system suppression.
    • Leiomyosarcoma: A rare cancer of smooth muscle cells that can present as a firm, painless nodule or bump, sometimes with a red rash.
    • Metastatic cancer: In rare cases, a red rash surrounding a mole could be a sign of metastatic cancer, such as breast or lung cancer that has spread to the skin.

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.

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