Presentation and Tumor Size in Patients with Vestibular Schwannoma: Analysis of a Multiple-Choice Questionnaire Study in 1,306 Patients

Background The symptoms of vestibular schwannomas at presentation range between cranial nerve symptoms, cerebellar symptoms, and symptoms related to hydrocephalus. A percentage of patients are diagnosed incidentally. The objectives of this study are to study the symptoms at presentation and the self-reported size at diagnosis in a large cohort of patients and relate it to age at diagnosis and year of diagnosis.

Methods A total of 1,306 patients diagnosed with vestibular schwannoma at Mayo Clinic, Rochester, and patients belonging to the Acoustic Neuroma Association (ANA) answered a multiple-choice questionnaire between 2015 and 2017. Demographic data, year of diagnosis, self-reported tumor size at diagnosis, symptoms at presentation, and duration of symptoms were reviewed. Statistical analysis using SPSS software was performed.

Results A total of 1,306 patients completed the initial questionnaire between 2015 and 2017. A total of 432 (33%) patients were treated at Mayo Clinic, Rochester, and 874 (66.9%) belonged to the ANA. The tumors of the patients in this database were diagnosed between 1966 and 2017 and the mean age at diagnosis was 51.8 years (8–99). 33.9% of the patients were males, 66.1% females. 1.1% of patients suffered from neurofibromatosis type 2 with bilateral tumors (14 patients), 48.8% were diagnosed on the right side, 50% on the left side. The self-reported tumor size at diagnosis was not known in 10.6% of the patients, 0 to 1 cm in 22.8%, 1 to 2 cm in 28.6%, 2 to 3 cm in 20.4%, 3 to 4 cm in 10%, and greater than 4 cm in 7.2% of the patients. 10% of the tumors were discovered incidentally. The primary symptom that led to diagnosis was hearing loss in 50.8% of the patients, dizziness in 16%, tinnitus is 10.9%, facial numbness in 4.9%, headaches in 4%, and facial twitching or paralysis in 1%. The mean duration of symptoms until diagnosis was 4 months. Smaller tumors were diagnosed in older patients as compared with larger tumors, which were diagnosed in younger patients p < 0.001. The mean age at diagnosis of smaller tumors (<1 cm) was 54.1 years, whereas the mean age at diagnosis in tumors greater than 4 cm was 42.4 years. Patients with tumors greater than 4 cm were symptomatic for a longer period of time than patients with smaller tumors (3.8 vs. 6.6 months, p < 0.001). The average age at diagnosis was significantly younger for NF 2 patients (43.9 vs. 51.8, p = 0.006). An increasing number of patients have been diagnosed incidentally in the past 5 years as compared with the previous decade (p = 0.011).

Conclusion In a large questionnaire-based database of 1,306 patients with diagnosis of vestibular schwannoma, the main symptom that led to diagnosis was hearing loss followed by dizziness. Neurofibromatosis type 2 and tumors larger than 4 cm were associated with younger patients. 10% of the tumors were discovered incidentally. Incidental diagnosis has been increasing in the last decade.