Abstract: Background and purpose: Nasal sinus adenoid cystic carcinoma is a rare head and neck tumor. Due to its high invasiveness and infiltrating growth habits along the nerve, as well as being adjacent to the eye structure, some patients had eye structure invasion at the time of their initial diagnosis, which made treatment difficult. This article summarized the clinical data and prognosis of patients with eye structure invasion of the nasal sinus adenoid cystic carcinoma, and discussed the treatment strategies of the disease and their efficacies. Methods: The study was a singlecenter, retrospective study of 138 patients with nasal sinus adenoid cystic carcinoma who underwent radiotherapy in Department of Radiation Oncology of Shanghai Eye and ENT Hospital of Fudan University from Jan. 2005 to Oct. 2017. The primary endpoint overall survival (OS) was estimated using the Kaplan-Meier method. Comparisons of OS between groups were performed using time series tests and Cox proportional hazards regression analysis was performed when appropriate. Pearson χ2 test was used for comparison between categorical variable groups. Results: There were 74 males (53.6%) and 64 females (46.4%) included in the study. The average age was (51.0±11.6) years. The nasal cavity was the most common primary site, with a total of 97 cases (70.3%). The clinical stage was mainly Ⅲ-Ⅳ, with a total of 97 cases (70.2%). Preoperative radiotherapy was performed in 24 patients (17.4%), 86 patients received postoperative radiotherapy (62.3%), and 28 patients received radiotherapy alone (20.3%). The average dose of radiotherapy was (64.8±4.5) Gy. There were 54 cases (39.1%) with eye invasion and 84 cases (60.9%) without eye invasion. Eyeballs were reserved in 40 cases (89.9%), whereas resection of eyeballs were performed in 14 cases (10.1%). There were 16 patients (29.6%) who received preoperative radiotherapy, 24 (44.4%) received postoperative radiotherapy, and 14 (25.9%) received radiotherapy alone of the 54 patients who had the invasion of eye structure. The 1-, 3-, 5-, and 11-year OS rates in 54 patients with eye invasion were 94.4%, 81.3%, 71.4% and 66.6%, respectively. The 1-, 3-, 5-, and 11-year OS rates were 98.8%, 95.6%, 93.9% and 75.4% among the 84 patients without eye invasion, respectively. The OS of early-stage patients (T₁+T₂) was significantly better than that of patients of T₃, T_4a and T_4b. The efficacy of the treatment in patients who had nasal sinus adenoid cystic carcinoma without eye invasion was significantly better compared with patients with eye invasion (P=0.016). The survival of the group with reserved eyeballs was superior to the survival of the eyeballs resection group (P=0.002). Preoperative radiotherapy may achieve better results for patients with eye invasion (compared with postoperative radiotherapy, P=0.081; compared with radiotherapy alone, P=0.096). Conclusion: The curative effect of the treatment for nasal sinus adenoid cystic carcinoma is significantly related to T stage. The efficacy of the treatment for nasal sinus adenoid cystic carcinoma with eye invasion is poor. Preoperative radiotherapy may improve the survival of this type of patients.

Key words: Nasal sinuses, Adenoid cystic carcinoma, Eye structure, Radiotherapy, Prognosis