Vestibular Schwannoma Growth with Aspirin and Other Nonsteroidal Anti-inflammatory Drugs

Objective: To investigate whether the use of aspirin or other non-steroidal anti-inflammatory drugs (NSAIDs) impact the growth of vestibular schwannoma (VS). Study Design: Retrospective case series. Setting: Single academic, tertiary care center. Patients: Patients with VS who underwent at least two magnetic resonance imaging (MRI) studies before intervention. Intervention(s): Serial MRI studies. Main Outcome Measure(s): VS tumor growth, defined as more than or equal to 2mm increase in the maximum tumor diameter between consecutive MRI studies, or between the first and last available study. Mean growth rate was also calculated, defined as the change in tumor size divided by length of follow-up. Results: A total of 564 VS patients met inclusion criteria, with 234 (41.2%) taking some type of NSAID. Aspirin use was not associated with VS tumor growth, presenting tumor diameter, or mean VS growth rate. Further, aspirin dosage did not impact growth outcomes or presenting tumor diameter. A total of 96 (17.0%) patients took an NSAID other than aspirin. Neither non-aspirin NSAID use nor degree of cyclooxygenase-2 (COX-2) selectivity, including aspirin, was significantly associated with VS tumor growth, presenting tumor diameter, or mean VS growth rate. Conclusions: While previous studies have suggested a relationship between aspirin usage and VS growth, we found no significant association in our series of 564 observed VS. Furthermore, there was no apparent relationship between aspirin dosage, non-aspirin NSAID use, and COX-2 selectivity with VS growth, presenting tumor diameter at presentation, or mean VS growth rate.