Primary Merkel Cell Carcinoma: The Clinical Experience of Taipei Veterans General Hospital Revisited

BACKGROUND: Merkel cell carcinoma (MCC) is rare among Asians. To evaluate the presence and characteristics of MCC in Taiwan, we described the characteristics, treatment, and prognostic findings of MCC in our institution. METHODS: We revisited and carried out a retrospective chart review of 16 consecutive patients with MCC treated from 1995 to 2018. Patient demographic data, tumor size, location, previous treatment, and follow-up data about presence of locoregional recurrence and metastasis were evaluated. RESULTS: There were 14 male and 2 female patients (mean age = 75.1 years; range = 26-91 years). Clinical follow-up revealed local recurrences in 5 patients 1 to 4 months after surgical excision. Lymph node metastasis was observed in 3 patients. We reviewed previously published articles and analyzed the clinical findings, pathologic examinations, and treatments. CONCLUSIONS: Surgical wide excision of the primary tumor remains the mainstay of treatment for patients with local/regional MCC. Additional management strategies, such as lymphadenectomy, radiotherapy, chemotherapy, and targeted therapy, depend on the presence or absence of clinically detectable lymph node disease. The prognosis for MCC is variable. Our findings highlight the importance of maintaining a high clinical suspicion for this malignancy in the appropriate clinical context to avoid delays in diagnosis and management.