Adjuvant radiotherapy in sinonasal mucosal melanoma: A retrospective analysis.

Abstract

Evaluation of outcome after curative treatment for sinonasal mucosal melanoma focused on the effect of adjuvant radiotherapy on recurrence and survival. Retrospective chart analysis. Tertiary referral hospital. Fifty-one patients with primary sinonasal mucosal melanoma who underwent surgical resection with curative intention between 1980 and 2016 at Erasmus Medical Center, Rotterdam. Patients were categorised into 2 groups: surgery alone and surgery with adjuvant radiotherapy. Log-rank test was used to compare rates of recurrence and survival between treatment groups. Predictors for treatment modality, recurrence and survival were assessed with multivariate statistical analysis. Of all patients, 23.5% developed local recurrence and 47.1% developed distant metastasis. Estimated 5-year disease-free survival was 25.2%, and 5-year overall survival (OS) was 38.1%. Forty-three patients (84.3%) were treated with post-operative radiotherapy. Patients who underwent surgery with adjuvant radiotherapy presented more often with high tumour stage, tumour involving multiple sites and positive margins. Post-operative radiotherapy seemed to be associated with better local control (P=.549). No effect was found on occurrence of distant metastasis and OS. Positive margin status was an independent negative predictor for distant metastasis-free survival and overall survival. Our treatment outcomes are consistent with literature. Post-operative radiotherapy seems to be associated with improved local control despite advanced disease and positive margin status in this treatment group.