Late subsequent Merkel cell carcinoma after 21 years of the first primary diagnosis: When to de-escalate surveillance?

Key Clinical Message: Merkel cell carcinoma (MCC) presents challenges in surveillance due to varied recurrence rates and uncertain follow-up protocols, especially in late recurrent cases. These cases need personalized monitoring strategies beyond traditional timelines, such as clinical and molecular factors, in order to optimize patient outcomes.

Abstract: Merkel cell carcinoma (MCC) is a rare, aggressive skin cancer with neuroendocrine differentiation with a propensity for recurrence following initial treatment.