Merkel Cell Carcinoma

Overview

Merkel cell carcinoma (MCC) is a rare but aggressive neuroendocrine skin cancer that typically appears as a painless, rapidly growing, firm nodule on sun-exposed skin. It is most common in older adults and immunosuppressed individuals. MCC has a high risk of recurrence and metastasis, making early detection and treatment critical.

Key Symptoms

Rapidly growing, firm, painless, dome-shaped nodule
Red, pink, blue, or violet coloration
Shiny, smooth surface that may ulcerate
Typically less than 2 cm at diagnosis but can grow quickly
Most often appears on sun-exposed areas in elderly patients
Usually solitary; may be mistaken for a cyst or benign growth

Affected Areas

Head and neck (most common), Arms, Legs, Trunk

Care Instructions

Seek immediate evaluation by a dermatologist for any rapidly growing skin nodule.
Biopsy and immunohistochemical staining are essential for accurate diagnosis.
Wide local excision or Mohs surgery with sentinel lymph node biopsy is standard treatment.
Radiation therapy is often recommended as adjuvant treatment.
Immunotherapy (such as avelumab or pembrolizumab) may be used for advanced or metastatic MCC.
Frequent follow-up with clinical exams and imaging is critical due to high recurrence risk.

Medical Disclaimer: This information is for educational purposes only and does not replace professional medical advice. Always consult a qualified dermatologist for diagnosis and treatment.

Prevalence: Rare; approximately 3,000 new cases per year in the United States