Analysis of Factors Affecting Adjuvant Radiation Therapy Timing in Sinonasal Malignancies

Introduction: Delays in initiation of adjuvant therapy are associated with poorer outcomes in patients who have undergone oncological resection for head and neck malignancy. There are many potential factors that can contribute to these delays, but unique to cancers that involve the base of skull is the potential to create communications that produce a leak in cerebral spinal fluid (CSF). This study aims to evaluate variables that may produce delays in postoperative adjuvant radiotherapy for patients undergoing sinonasal malignancy surgery.

Method: After approval from our institutional review board, a single-institution retrospective review of all patients undergoing endoscopic or open surgery for sinonasal malignancies from January 2007 to December 2017 were identified. Clinically relevant data, including basic demographics, tumor characteristics, procedure details, postoperative course and interested dates were tabulated. The covariates of surgical approach, tumor T stage (T1/2 vs. T3/4), reconstruction type, presence of an intraoperative CSF leak, and geographic location of radiation therapy were analyzed to see if they significantly impacted time to initiation of radiation therapy.

Results: Of the 361 patients found on initial screening, 36 were identified to have a surgically resected primary sinonasal malignancy followed by radiation or chemoradiation therapy. Of these, 2 were excluded for incomplete data. The average number of days from surgery to initiation of radiation therapy was 50 (range: 21–86). No difference was found comparing endoscopic to open surgery (p = 0.80, CI: −12.6 to 9.9), tumor stage (p = 0.66, CI: −14.6 to 22.18), reconstruction method (p = 0.86), presence of an intraoperative CSF leak (p = 0.18, CI: −19.2 to 3.8), occurrence of an immediate postoperative complication (p = 0.36, CI: −19.7 to 7.3), or geographic location of radiation therapy (p = 0.10, CI: −26.8 to 2.6).

Conclusion: This study suggests that adequate surgical resection, including base of skull resection with the potential of encountering a CSF leak, achieved by the appropriate approach and robust reconstruction for all tumor stages does not delay initiation of radiation therapy in sinonasal malignancies.

No conflict of interest has been declared by the author(s).