Vestibular schwannoma between 1 and 3 cm: importance of the tumor size in surgical and functional outcome.

OBJECTIVE The aim of the study was to compare the surgical and functional outcomes of the microsurgical osteoplastic retro-sigmoid approach in a semi-sitting position in two groups of patients with vestibular schwannomas (VSs) ranging from 1 to 3 cm in size. METHOD A 5-year retrospective evaluation was made of these two groups of patients with VS: Patients with VS sizes 1-<2 cm in maximal intra/extrameatal diameter (n=292) were assigned to group "A" and a matched group of patients with VS between 2 and 3 cm in size (n=154) were assigned to group "B". RESULTS Significant differences in postoperative outcomes (p<0.05) were found for facial nerve function of House-Brackmann grade I (94% group A vs. 78% group B) and preservation of preoperative hearing (51% group B vs. 34% group A). Patients with tumors sizes ranging between 1 and <2 cm exhibited total tumor removal with significantly higher facial nerve preservation and hearing function preservation rates compared with patients with tumors 2-3 cm in size. CONCLUSION Even a small increase in tumor size correlated with a significant reduction in good hearing and facial preservation postoperatively, which implies that tumor removal should be performed at the earliest stage possible. Furthermore, these results contradict recommending the wait-and-see approach for intra/extrameatal tumors.