The role of induction chemotherapy for orbital invasion in sinonasal malignancies: A systematic review

Background: Sinonasal malignancies (SNMs) frequently present with orbital invasion. Orbital exenteration (OE) can lead to significant morbidity. Induction chemotherapy (IC) is a promising treatment alternative that may allow for orbit preserving (OP) treatments without compromising patient survival. This systematic review was conducted to synthesize the published data on SNM patients with orbital invasion who underwent IC, including tumor response, orbital outcomes, and survival. Methods: The study protocol was designed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Databases Embase, Cochrane, Medline, and Scopus, from inception to July 17, 2023, were searched. Results: Nineteen studies were included, encompassing 305 SNM patients with orbital invasion treated with IC. Fourteen studies reported an overall IC response rate (positive response defined as complete or partial tumor volume reduction) of 77.2%. Among included studies, OE rates after IC ranged from 0 to 40%. Three studies reported a high rate of posttreatment functional orbital preservation (89.8–96.0%). Five studies specifically reported that 62.5% (60 out of 96) of patients were downgraded from planned OE to OP treatment following IC. Three studies reported a significant overall survival (OS) improvement in IC responders versus IC nonresponders. Following IC, 5-year OS ranged from 44.2 to 55.5%. Patients with olfactory neuroblastoma demonstrated the highest IC response rate and lowest OE rate (100 and 0%, respectively) versus those with sinonasal undifferentiated carcinomas (68.4 and 0%) or squamous cell carcinomas (76.7 and 16%). Conclusions: For select patients, IC may allow for OP in locally advanced SNMs with orbital involvement.