Merkel cell carcinoma: A clinically oriented mini-review for dermatologists

Area of Science:

• Dermatology
• Oncology
• Pathology

Background:

• Merkel cell carcinoma (MCC) is a rare, aggressive skin cancer with increasing incidence.
• It disproportionately affects the elderly, immunosuppressed, and fair-skinned individuals.
• MCC often presents as a rapidly growing nodule on sun-exposed skin, but atypical presentations can delay diagnosis.

Purpose of the Study:

• To provide a clinically oriented mini-review of MCC for dermatologists.
• To summarize current evidence on MCC epidemiology, diagnosis, staging, and treatment.
• To highlight recent advances and remaining disparities in MCC management.

Main Methods:

• Review of current evidence on MCC.
• Summary of diagnostic criteria including histopathology and immunohistochemistry.
• Overview of imaging modalities, prognostic factors, biomarkers, and treatment options.

Main Results:

• Diagnosis relies on histopathology and immunohistochemistry (CK20, MCPyV markers).
• FDG-PET/CT is essential for staging and surveillance.
• Prognosis depends on tumor size, stage, immune status, age, and viral status.

Conclusions:

• MCC requires early recognition, accurate staging, and multidisciplinary care.
• Advances in imaging, biomarkers, and immunotherapy have improved outcomes.
• Global disparities in access to diagnostics and modern therapies persist.