The authors present the guidelines of the REFCOR (French Rare Head-and-Neck Cancer Expert Network) for sinonasal mucosal melanoma.

A multidisciplinary working group made a systematic review of the literature. The formalized expert consensus methodology was followed in drawing up recommendations, which were presented according to the degree of agreement between members of the review group.

Strong agreement: it is recommended to perform systematic regional and remote extension assessment at diagnosis; PET-CT is the gold standard for remote assessment; isolated radiotherapy is not recommended for curative treatment; given the major risk of metastasis and the poor prognosis, alternatives to heavy destructive surgery should be considered in the rare cancer multidisciplinary tumor board; it is recommended to screen for NRAS, BRAF and KIT mutations, to identify possible treatment targets; reference imaging should be performed 3 months after end of treatment, using sinonasal and brain MRI and PET-CT; due to the risk of early recurrence, close follow-up is recommended during the first 2 years, then at least every 6 months up to 5 years postoperatively. Relative agreement: operable sinonasal mucosal melanoma should be treated by total macroscopic resection with negative margins followed by radiotherapy on the tumor bed; postoperative radiotherapy is recommended, to improve local control; neoadjuvant or adjuvant chemotherapy, other than immunotherapy or targeted therapy, is not recommended; for non-resectable and/or metastatic sinonasal mucosal melanoma, immunotherapy is the systematic first-line treatment; prophylactic lymph-node treatment is not recommended in N0 sinonasal mucosal melanoma; lymph-node surgery is recommended in N+ cases without remote metastasis, including cases of regional recurrence.