# Merkel Cell Tumor: A Mystery Beneath the Surface

## TL;DR

This paper presents a rare case of Merkel cell carcinoma in a 70-year-old patient, emphasizing the importance of histopathology and immunohistochemistry for accurate diagnosis.

## Contribution

The novelty lies in presenting an atypical case of MCC with a long-standing lesion, expanding the understanding of its clinical variability.

## Key findings

- A 70-year-old patient presented with a solitary, asymptomatic lesion lasting one year.
- Histopathological and immunohistochemical analysis was crucial for confirming the diagnosis.
- The case highlights the importance of considering MCC in atypical presentations.

## Abstract

Merkel cell carcinoma (MCC) is an aggressive skin condition that requires prompt diagnosis and management. It predominantly affects older adults and has a high propensity for recurrence and metastasis. The acronym AEIOU, which stands for asymptomatic, expanding rapidly, immunosuppression, older than 50 years, and UV radiation, is often used in the approach to diagnosis.

We present a unique and intriguing case of a 70-year-old patient with a solitary and asymptomatic exophytic lesion on her right forearm that had been present for one year. She had not received any treatment or medical advice to date.

Our case contributes to the literature on MCC, highlighting the variety of differential diagnoses that can occur in an atypical variety such as the one we are describing. We recall the relevance of the histopathological approach, emphasizing the crucial role of immunohistochemistry in the presumptive diagnosis of this entity.