Intratumoral hemorrhage in vestibular schwannomas after stereotactic radiosurgery

Abstract

OBJECTIVE Vestibular schwannomas (VSs) are benign tumors of the cerebellopontine angle that are typically managed with stereotactic radiosurgery (SRS). Intratumoral hemorrhage (ITH) of VSs is a rare occurrence that results in worsening vestibular and new cranial nerve deficits. Few reports have described the management and outcomes of this entity after SRS. To further delineate the incidence and impact of this event, the authors performed a retrospective review of their VS SRS patients at a single center. METHODS Between 1987 and 2022, 2058 patients with VSs underwent Gamma Knife radiosurgery (GKRS) at the University of Pittsburgh Medical Center. The authors performed a review of the prospectively maintained VS database at their center to identify patients with ITH. The presentation, management, and clinical and imaging outcomes of the patients are reported. RESULTS A total of 1902 VS patients had sufficient clinical and imaging follow-up data. Five Koos grade III (n = 1) and IV (n = 4) VS patients developed ITH after GKRS, resulting in a cumulative incidence rate of 0.26%. The age at presentation ranged from 62 to 79 years, and 3 patients were male. The time from VS diagnosis to GKRS ranged from 1 to 13 months, and the time from GKRS to ITH ranged from 2 to 130 months. Three patients had bleeding risk factors. One patient required urgent surgical intervention due to the ITH volume, while the other 4 patients were initially observed. Three patients remained stable and required no delayed intervention; 1 patient required delayed resection because of symptom progression and hemorrhagic expansion. Histopathological analysis revealed multiple fragments of S-100–positive cells, hemorrhage, and hemosiderin-laden macrophages. At last follow-up, 4 patients had clinically improved and 1 patient remained stable. CONCLUSIONS ITH after VS radiosurgery is a rare phenomenon with a cumulative incidence rate of 0.26% in this series. Patient-tailored management in the form of observation or resection is based on patient presentation, acuity, and ITH size.

Intratumoral Hemorrhage in Vestibular Schwannomas After Stereotactic Radiosurgery: Multi-Institutional Study

“…1,2 A recent study found a cumulative incidence of ITH of 0.26% (5 ITH of 1902 patients with VS) among patients with VS after stereotactic radiosurgery (SRS). 3 These results contrast with another series that found ITH cumulative incidence of 0.4% among newly diagnosed or observed (ie, wait and watch) VS. 4…”

“…stereotactic radiosurgery (SRS). 3 These results contrast with another series that found ITH cumulative incidence of 0.4% among newly diagnosed or observed (ie, wait and watch) VS. 4 While ITH in patients with VS who have had surgery or have been observed has been researched before, few reports have explored the incidence of ITH in VS after SRS. [4][5][6] Therefore, our multi-institutional study aims to describe ITH incidence, patient characteristics, management strategies, and clinical outcomes in patients with VS who underwent SRS.…”

“…7 Initial VS SRS technique, follow-up and ITH identification protocols, and investigated variables were previously described. 3 Cohort Characteristics and Initial VS SRS Among the 9565 patients with VS who underwent SRS, 25 patients (13 female) developed ITH. The median age of these patients was 62 years (IQR, 48-71), and the median time interval between initial diagnosis and SRS was 4 months (IQR, 1-13) (Table 1).…”

“…Given the concern of ITH development in SRS-managed VS, the University of Pittsburgh reported their incidence and experience of ITH among 1902 patients with VS. 3 In their series, 5 patients had post-SRS VS ITH, with a cumulative incidence of 0.26%. 3 Similarly, the present article of 10 IRRF centers and 9565 patients with VS managed with SRS found ITH in 25 patients after SRS management, with a similar cumulative incidence of 0.26%. Conversely, Carlson et al 4 found an ITH cumulative incidence of 0.4% among conservatively managed patients with VS. Our results illustrate that SRS did not increase the risk of ITH, possibly because of its effect on tumor devascularization.…”

Two Cases of Rare Intratumoral Hemorrhage Following COVID-19 Vaccination

“…Intratumoral hemorrhage in vestibular schwannomas is rare, with a reported incidence of 0.4% in general [ 3 ] and 0.26% after SRS [ 4 ]. It usually occurs 80 or 130 months after SRS [ 4 , 5 ]. Although the mechanism of intratumoral hemorrhage and the effects of the radiation are not completely understood, anticoagulation has been cited as a risk factor for intratumoral hemorrhage in vestibular schwannomas [ 3 ].…”