Abstract
Merkel cell carcinoma (MCC) is a rare, aggressive skin cancer. The incidence has increased over the past 20 years, and this may be attributed to increased ultraviolet (UV) light exposure. MCC is more common among Caucasians, males, and individuals older than 69 years of age. Immunosuppressed patients are at a higher risk for MCC. MCC may present clinically as a dome-shaped red or blue nodule. The mnemonic “AEIOU” describes common clinical features: asymptomatic, expanding rapidly, immunosuppression, older than 50 years, and ultraviolet-exposed/fair skin. MCC most commonly presents on the head and neck, followed by the extremities and trunk. Diagnosis is made via biopsy, and the first-line treatment is surgical removal of the primary tumor. Sentinel lymph node biopsy (SLNB) is recommended for all patients: patients with negative sentinel lymph nodes (SLNs) may undergo wide local excision (WLE), Mohs micrographic surgery (MMS), or radiation to the primary tumor site. Patients with positive SLNs may undergo WLE or MMS, followed by complete lymph node dissection (CLND) and/or radiation to the nodal basin. Patients with metastatic disease may undergo chemotherapy or immunotherapy. Prognosis for MCC patients depends on the stage of disease: survival rates decrease as the stage advances. Due to the high recurrence rate of MCC, patients are encouraged to see their dermatologists frequently.
Keywords
Merkel cell carcinoma Skin cancer Epidemiology Clinical features Diagnosis Histopathology Staging Treatment PrognosisReferences
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