REFCOR good practice guidelines for radiotherapy in sinonasal carcinomas and mucosal melanomas.

[INTRODUCTION] The present REFCOR guidelines define indications for radiotherapy in sinonasal carcinoma and mucosal melanoma.

[METHODS] They result from multidisciplinary consensus based on a critical review of the literature, feedback from expert centers, and a structured process to harmonize clinical practice across France.

[RESULTS] Indications for radiotherapy are determined by tumor-specific characteristics and histoprognostic factors. In France, treatment decisions for these tumors are discussed in regional or national REFCOR expert panel multidisciplinary tumor boards. Radiotherapy is most often adjuvant, delivered at a short postsurgical interval, but can be exclusive for unresectable tumors or when surgery is contraindicated. It should be performed by experienced teams. The timing of postoperative treatment and the tumoral and nodal targets are tailored to histology and disease stage; their definition is based on a comprehensive and accurate characterization of surgical specimens, including multibloc resections obtained through open or endoscopic endonasal approaches. Given the anatomical proximity of the paranasal sinuses to highly radiosensitive structures (neurological, optic, otologic, and mucosal), technique and quality are critical for achieving tumor control while minimizing morbidity. Conformal techniques such as IMRT or VMAT represent the current gold standard. Proton therapy may be considered to improve sparing of organs at risk.

[CONCLUSION] The REFCOR guidelines establish a framework for indications for precision radiotherapy within a multidisciplinary patient-centered approach adapted to individual tumor characteristics. For each patient, recommendations are complemented by REFCOR multidisciplinary tumor board discussion in a personalized care pathway.