[Guidelines for the diagnosis and treatment of Merkel cell carcinoma]

Merkel cell carcinoma (MCC) is a rare neuroendocrine carcinoma that originates in the skin. Epidemiological factors strongly associated with MCC are: age over 65 years, fair skin, history of extensive sun exposure and chronic immune suppression. The literature is sparse and many questions currently remain unanswered regarding optimal treatment of MCC.

To provide clinical practice guidelines for the diagnosis and treatment of MCC.

Literature data were analysed and the existing German and American practice guidelines were compared. Where German and US guidelines were identical, the recommendations in question were adopted. Regarding discordant points, a formalized consensus process was devised. The guidelines were then written by an editorial group and validated by the cutaneous oncology group of the French Society of Dermatology.

The guidelines were drawn up according to three levels of scientific evidence: a: complete agreement between the German and American guidelines; b: results of the formalized consensus process; c: expert opinion of the steering group based on available evidence. Our guidelines present up-to-date recommendations on clinical and pathological procedures for diagnosis, staging, surgical treatment, sentinel lymph node biopsy, radiotherapy and follow-up.

We created a set of diagnostic and treatment guidelines in order to standardize management of MCC, which may be not optimal throughout France.