The Value of Preoperative Radiotherapy in the Treatment of Locally Advanced Nasal Cavity and Paranasal Sinus Squamous Cell Carcinoma: A Single Institutional Experience

Abstract

The value of preoperative radiotherapy in the comprehensive treatment of locally advanced nasal cavity and paranasal sinus squamous cell carcinomas (NPSCCs) remains controversial. The aim of our study was to compare the efficacy of preoperative and postoperative radiotherapy and further to explore the value of preoperative radiotherapy in the treatment of locally advanced NPSCCs. One hundred and forty-two patients with locally advanced NPSCCs treated with pre- / postoperative radiotherapy plus surgery from our institution between January 1998 and December 2014 were retrospectively reviewed. All enrolled patients were divided into the two groups: preoperative radiotherapy (Pre-S RT) group and postoperative radiotherapy (PORT) group. The overall survival (OS), local control (LC), distance metastasis free survival (DMFS) and disease-free survival (DFS) between treatment groups were evaluated. A higher proportion of adverse prognostic factors, such as orbital content invasion, low RT dose, and 2D/3DCRT were found in preoperative radiotherapy group, which were confirmed to be associated with overall survival and/or local control by univariate and multivariate analysis. The median radiation dose of preoperative and postoperative radiotherapy was 60Gy and 69Gy (P value < 0.001). At a median follow-up of 49 months, preoperative radiotherapy achieved good LC, DFS, DMFS, and OS, not worse than postoperative radiotherapy. The 5-year OS, LC, DMFS, and DFS of Pre-S RT group were 55.1%, 59.1%, 78.7%, and 49.0%, while those of PORT group were 52.2%, 60.0%, 76.6%, and 47.3%, respectively (P value > 0.05). After preoperative radiotherapy, the complete resection rate reached 93.5%, significantly higher than 31.2% in the postoperative radiotherapy group (P value <0.001). Among the 50 patients with orbital contents invasion, the actual orbital content preservation rate of preoperative radiotherapy group was nearly 76%, higher than that of postoperative radiotherapy group (57%). The pathologic complete response (pCR) rate of the preoperative radiotherapy group was up to 30.6%. Compared with non-pCR group, pCR group had significantly higher 5-year OS, LC, DFS (P value < 0.05), and similar 5-year DMFS (P value > 0.05). In the absence of randomized controlled studies to guide treatment, this study confirmed the value of preoperative radiotherapy. Under the condition of more adverse factors, preoperative radiotherapy plus surgery not only achieved similar clinical outcomes to surgery plus postoperative radiotherapy, but also significantly improved complete resection rate and increased the chance of orbital contents preservation. More importantly, nearly a third of patients achieved pCR in the preoperative radiotherapy group, and this subgroup had the best prognosis.