Long-term outcomes and toxicities of carbon-ion radiotherapy in malignant tumors of the sphenoid sinus.

BACKGROUND: Most of the primary sphenoid sinus tumors present with locally advanced stages with involvement of adjacent critical structures and are not amenable to radical resection. We sought to evaluate the safety and efficacy of carbon-ion radiotherapy (C-ion RT) for sphenoid sinus malignancies. METHODS: This is a retrospective analysis of 22 patients of primary sphenoid carcinomas treated with definitive C-ion RT. RESULTS: Adenoid cystic carcinoma was the most common histology (15 patients, 68.2%). The median follow-up of this cohort was 48.5 months. The actuarial local control and overall survival at 5 years were 51.0% and 62.7%, respectively. Grade 4 visual impairment and grade 4 brain necrosis were seen in six and one patient, respectively. CONCLUSION: C-ion RT can provide a reasonably good clinical outcome in locally advanced sphenoid sinus malignancies with a marginally higher late toxicity profile because of extremely close proximity of the target volume to critical structures.

Sphenoid sinus malignancies: a population-based comprehensive analysis.

BACKGROUND: Sinonasal malignancies are rare, representing less than 1% of all cancers, with the sphenoid sinus accounting for 1% to 2% of these cases. Sphenoid sinus malignancies exhibit very poor outcomes. There is a paucity of literature describing their histopathological features, incidence trends, treatment, and survival. We seek to elucidate these factors using a national population-based resource. METHODS: The Surveillance, Epidemiology, and End Results (SEER) database was used to identify malignant sphenoid sinus tumors. The results were analyzed for demographics, incidence, and clinicopathologic trends. Survival was calculated using Kaplan-Meier analysis. RESULTS: The search identified 472 cases. The mean and median age at diagnosis was 60.0 years. Males represented 54.9% of cases. By race/ethnicity, 82.4% were white and 8.5% were black. The four most common histopathologies were squamous cell neoplasms (29.4%), adenocarcinomas (14.4%), non-Hodgkin's mature B-cell lymphomas (13.1%), and unspecified epithelial neoplasms (11.0%). The overall incidence from 2000 to 2012 was 0.030 per 100,000. Kaplan-Meier analysis demonstrated an overall 5-year disease-specific survival (DSS) of 48.1%. Of the most common histopathological subtypes, 5-year DSS was best for mature B-cell NHL (64.0%) and worst for unspecified epithelial neoplasms (25.6%). CONCLUSION: Sphenoid sinus malignancies are rare, with high prevalence in white males. The most common histopathology is squamous cell neoplasms. They exhibit significant locoregional extension. Of the common sphenoid sinus malignant subtypes, 5-year DSS is best for mature B-cell NHL and worst for unspecified epithelial neoplasms.