[Treatment and prognosis analysis of perineural invasion on sinonasal adenoid cystic carcinoma].

To analyze the efficacy of sinonasal adenoid cystic carcinoma (ACC) with perineural invasion (PNI), and explore the prognostic value of PNI on sinonasal adenoid cystic carcinoma. The clinical data of 105 patients with sinonasal ACC admitted to Cancer Hospital, Chinese Academy of Medical Sciences from January 2000 to December 2016 were retrospectively reviewed. All patients were restaged according to American Joint Committee on Cancer 8th edition. Follow-up visits were conducted to obtain information of treatment failure and survival outcome. The Log rank test was used for univariate analysis of prognostic factors, and Cox regression model was used for multivariate prognostic analysis. The maxillary sinus (=59) was the most common primary site, followed by the nasal cavity (=38). There were 93 patients with stage Ⅲ-Ⅳ. The treatment modalities included surgery alone (=14), radiotherapy alone (=13), preoperative radiotherapy plus surgery (=10), and surgery plus postoperative radiotherapy (=68). The median follow-up time was 91.8 months, the 5-year local control (LC), distant metastasis-free survival (DMFS), progression-free survival (PFS), and overall survival (OS) rates were 72.6%, 73.0%, 52.9% and 78.0%, respectively. There were 33 patients (31.4%) with PNI-positive. The 5-year DMFS, PFS, and OS rates of PNI-positive group were 53.7%, 29.4% and 56.5%, respectively, which were significantly inferior to those of PNI-negative group (80.8%, 63.0% and 86.8%, respectively, <0.05), while there was no significant difference in the 5-year LC rate between both groups (64.5% vs 76.5%, =0.273). The multivariate Cox regression analysis showed PNI was one of the poor prognostic factors of DMFS (=3.514, 95% 1.557-7.932), PFS (=2.562, 95% 1.349-4.866) and OS (=2.605, 95% 1.169-5.806). Among patients with PNI-positive, the 5-year LC, PFS and OS rates of patients received surgery combined with radiotherapy were 84.9%, 41.3% and 72.7%, respectively, which were significantly higher than 23.3%, 10.0% and 26.7% of patients receiving surgery or radiotherapy alone (<0.05). The presence of PNI increases the risk of distant metastasis in patients with sinonasal ACC. Compared with patients with PNI-negative, the prognosis of patients with PNI-positive is relatively poor, and surgery combined with radiotherapy for PNI-positive sinonasal ACC results in good clinical outcomes.