Sinonasal mucosal melanoma: Is there a need for elective neck irradiation?

BACKGROUND AND PURPOSE:Sinonasal mucosal melanoma (SNMM) is a rare malignant neoplasm. The regional failure pattern and effectiveness of elective neck irradiation (ENI) were not well defined. Here, we would assess the value of ENI for clinical node negative (cN0) SNMM patients. MATERIALS AND METHODS:A total of 107 SNMM patients treated at our institution over a period of 30 years was retrospectively analyzed. RESULTS:Five patients had lymph node metastases at diagnosis. Among the 102 cN0 patients analyzed, 37 patients had received ENI, and 65 patients had not. ENI significantly reduced the regional recurrence rate from 23.1% (15/65) to 2.7% (1/37). Ipsilateral levels Ib and II were the most common locations of regional relapse. Multivariate analysis also showed that ENI was the only independent favorable predictor for the achievement of regional control (HR: 9.120; 95% CI: 1.204-69.109; P = 0.032). CONCLUSION:This is the largest cohort of SNMM patients from a single institution analyzed for the assessment of the value of ENI on regional control and survival. ENI significantly reduced the regional relapse rate in our study. Ipsilateral levels Ib and II might be considerable when deliver elective neck irradiation, more evidence is needed in the future.