Merkel Cell Carcinoma: Literature Review and Clinical Case Analysis

Abstract

Backgroud: Merkel cell carcinoma is a cutaneous tumor, also known as neuroendocrine carcinoma, that is infrequent and highly aggressive, with a high mortality rate. 1 It primarily affects individuals over 60 years of age, those with immunosuppression, or those infected with the polyomavirus (MCPyV). It is an underdiagnosed tumor due to the nonspecificity of its clinical and dermatological manifestations. The definitive diagnosis is made by histopathological study, with identification of the sentinel lymph node being essential, since the presence of metastases is associated with a significant decrease in five-year survival. Although there is no optimal treatment, surgery remains a therapeutic pillar, complemented by radiotherapy and immunotherapy as adjuvant treatments. Material And Methods: The study was conducted using a mixed-method design, comprising a descriptive literature review conducted in scientific databases (PubMed, SciELO, Cochrane Library, and Elsevier), prioritizing recent population-based studies addressing the incidence, mortality, and survival associated with Merkel cell carcinoma. This was complemented by clinical follow-up of a 55-year-old female patient diagnosed with the condition in 2021. Results: The patient consulted on 06/25/2021 for a painless red nodule in an exposed region. The diagnosis was confirmed by biopsy on 01/07/2021. Despite the treatment, he developed lymph node and distant metastases and died in 2023. The revised bibliography shows a low overall survival, especially in advanced stages. Conclusion: The CCM continues to be an underdiagnosed neoplasm. Its early detection is key to improving prognosis and increasing survival. Despite the early diagnosis, the patient did not exceed three years of survival, which shows that the CCM can have aggressive clinical behavior even in the initial stages.