Surgical Management and Prognostic Factors for Endolymphatic Sac Tumor: A Single-Institute Experience with a Systematic Review

OBJECTIVE: To evaluate the clinical features, surgical outcomes, and predictors of progression-free survival (PFS) in patients with endolymphatic sac tumors (ELSTs). METHODS: This retrospective study analyzed 15 cases from Beijing Tiantan Hospital and 237 from the literature (1988-2023), focusing on patients with pathologically confirmed intracranial or skull ELSTs who had comprehensive treatment and follow-up records. Univariate and multivariate Cox regression analyses were used to identify factors influencing PFS. RESULTS: Patients from our institute comprised 10 males and 5 females, with an average age of 39.1 years. Among these patients, 86.7% underwent gross total resection (GTR). During the follow-up period, 2 patients (13.3%) were lost to follow-up. After a mean follow-up of 74.9 months, 1 patient experienced recurrence and another died from unrelated causes. A review of the literature identified 237 additional patients, including 134 females (56.5%), with an average age of 39.8 years; 22.8% of these patients had von Hippel-Lindau disease. The GTR rate was 69.2%. After a mean follow-up of 53.2 months, 33 recurrences occurred, and the median PFS was 48 months. In addition, 8 patients died during the follow-up period; none of the deaths was attributed to ELSTs. Multivariate analysis identified GTR (hazard ratio, 0.279; 95% confidence interval, 0.086-0.903; P [ 0.033) as a significant protective factor against recurrence among the pooled cases. CONCLUSIONS: GTR is crucial for improving PFS in patients with ELST, emphasizing the need for advanced surgical techniques and long-term follow-up because of potential recurrences.