Michele Bailo1, Nicola Boari2, Filippo Gagliardi1, Alberto Franzin1, Martina Piloni1, Alfio Spina1, Marco Gemma3, Antonella Del Vecchio4, Angelo Bolognesi5, Pietro Mortini6. 1. Department of Neurosurgery, I.R.C.C.S. Ospedale San Raffaele, Milan, Italy. 2. Department of Neurosurgery, I.R.C.C.S. Ospedale San Raffaele, Milan, Italy. Electronic address: boari.nicola@hsr.it. 3. Service of Neuro-anesthesia, I.R.C.C.S. Ospedale San Raffaele, Milan, Italy. 4. Service of Medical Physics, I.R.C.C.S. Ospedale San Raffaele, Milan, Italy. 5. Service of Radiation Oncology, I.R.C.C.S. Ospedale San Raffaele, Milan, Italy. 6. Department of Neurosurgery, I.R.C.C.S. Ospedale San Raffaele, Milan, Italy; Vita-Salute San Raffaele University, Milan, Italy.
Abstract
OBJECTIVE: Complete removal of vestibular schwannomas (VS) is not always achievable without any risk of disabling postoperative complications, especially in terms of facial nerve function. Moreover, even after gross total removal, a relevant rate of recurrence has been reported. The aim of this study is to validate Gamma Knife radiosurgery (GKRS) as an effective strategy to treat tumor regrowth after previous surgery. METHODS: Ninety patients treated with GKRS for VS after previous microsurgery were included in the present study. GKRS was performed at a median of 31 months (range, 4-174 months) postoperatively. Mean tumor volume was 3.35 cm3 (median, 2.5 cm3; range, 0.027-13 cm3) and median marginal dose was 13 Gy. RESULTS: At a mean follow-up of 77.2 months, tumor control was achieved in 90% of patients: 2 patients underwent repeated GKRS, and 7 patients underwent further microsurgery. Tumor shrinkage at last follow-up was recorded in 80.3% of cases. The complication rate was low and many consisted of a transient worsening of preexisting symptoms. The overall incidence of persisting facial nerve deficit and trigeminal nerve impairment was, in both cases, 3.3%. Two of 5 patients (40%) preserved functional hearing at last follow-up. One patient (1.1%) underwent ventriculoperitoneal shunting 12 months after GKRS. CONCLUSIONS: GKRS is a safe and effective treatment for growing residual and recurrent VSs, with tumor control obtained in 90% of cases and a low morbidity rate. Moreover, the possibility of treating patients with major medical comorbidities constitutes a significant advantage over repeated surgery.
OBJECTIVE: Complete removal of vestibular schwannomas (VS) is not always achievable without any risk of disabling postoperative complications, especially in terms of facial nerve function. Moreover, even after gross total removal, a relevant rate of recurrence has been reported. The aim of this study is to validate Gamma Knife radiosurgery (GKRS) as an effective strategy to treat tumor regrowth after previous surgery. METHODS: Ninety patients treated with GKRS for VS after previous microsurgery were included in the present study. GKRS was performed at a median of 31 months (range, 4-174 months) postoperatively. Mean tumor volume was 3.35 cm3 (median, 2.5 cm3; range, 0.027-13 cm3) and median marginal dose was 13 Gy. RESULTS: At a mean follow-up of 77.2 months, tumor control was achieved in 90% of patients: 2 patients underwent repeated GKRS, and 7 patients underwent further microsurgery. Tumor shrinkage at last follow-up was recorded in 80.3% of cases. The complication rate was low and many consisted of a transient worsening of preexisting symptoms. The overall incidence of persisting facial nerve deficit and trigeminal nerve impairment was, in both cases, 3.3%. Two of 5 patients (40%) preserved functional hearing at last follow-up. One patient (1.1%) underwent ventriculoperitoneal shunting 12 months after GKRS. CONCLUSIONS: GKRS is a safe and effective treatment for growing residual and recurrent VSs, with tumor control obtained in 90% of cases and a low morbidity rate. Moreover, the possibility of treating patients with major medical comorbidities constitutes a significant advantage over repeated surgery.
Authors: Won Jae Lee; Jung Il Lee; Jung Won Choi; Doo Sik Kong; Do Hyun Nam; Yang Sun Cho; Hyung Jin Shin; Ho Jun Seol Journal: J Korean Med Sci Date: 2021-04-26 Impact factor: 2.153