Vestibular schwannomas (VS), also named acoustic neurinoma, are benign tumors that originate from the Schwann cells of one of the four vestibular nerves (two at each side). These nerves are part of... Show moreVestibular schwannomas (VS), also named acoustic neurinoma, are benign tumors that originate from the Schwann cells of one of the four vestibular nerves (two at each side). These nerves are part of the eighth cranial nerve, the vestibulocochlear nerve, also known as the statoacoustic nerve. The vestibular nerves are located in the cerebellopontine angle, the space between brainstem, cerebellum and temporal bone. VS are the most common neoplasm located in the cerebellopontine angle and account for 8% of all intracranial tumors (1). The majority (95%) of VS are sporadic and occur unilateral. VS may exhibit a remarkable variable growth pattern: some tumors show a clear progression while others remain dormant and on occasion undergo shrinkage (2). The clinical symptoms most frequently seen are progressive (unilateral) hearing loss, vertigo, and tinnitus. Options for Treatment are observation (wait and scan), radiotherapy, or microsurgery. The choice of treatment depends on tumor size, severity and progression of the clinical symptoms, age of the patient, and patient preference.This thesis describes some of the clinical aspects of VS which are relevant for treatment. These concern the epidemiology, diagnostic challenges, clinical predictors affecting selection, and surgical technique and outcome. Show less
Objective Vestibular schwannomas are benign tumors that are often managed by radiotherapy. Minimizing long-term toxicity is paramount for a population that remains at normal life expectancy and at... Show moreObjective Vestibular schwannomas are benign tumors that are often managed by radiotherapy. Minimizing long-term toxicity is paramount for a population that remains at normal life expectancy and at risk for loss of quality of life for years if not decades. Whereas current radiotherapy standard utilizes photon radiation, proton radiotherapy characteristics may enable a reduction of toxicity by reducing the volume of collateral irradiated healthy tissue. A systematic review was conducted to assess tumor control and short- and long-term sequelae after proton irradiation. Methods Studies that reported on treatment outcomes of proton radiotherapy in vestibular schwannoma patients were included. Results Five peer-reviewed retrospective series met the inclusion criteria. Quality of the studies varied from low to good. There were 276 unique patients described. Tumor control rates ranged from 85 to 100% (radiological median follow-up of 2.2-7.4 years). Hearing loss rates, defined as losing Gardner Robertson class I/II hearing, showed an weighted crude average 52% (depending on follow-up duration). The weighted averages for post-irradiation facial and trigeminal neuropathy were 5% and 4%, respectively. The risk of neuropathy seems to decrease with lower radiation dosages. Conclusion Proton irradiation for vestibular schwannomas achieves high tumor control rates, equivalent to photon irradiation. Reported cranial nerve preservation rates vary, partly due to an apparent selection bias with a high percentage of patients with clinical symptoms prior to treatment. Results of cranial nerve function preservation, quality of life, and cognitive functioning are currently insufficiently reported. In addition, advances in proton radiotherapy technology warrant re-evaluation of current techniques and protocols for the management of vestibular schwannomas. Show less
Kleijwegt, M.; Ho, V.; Visser, O.; Godefroy, W.; Mey, A. van der 2016
Vestibular schwannomas are benign intracranial tumors which generally arise from the Schwann cells of the superior part of the vestibular portion of the eight cranial nerve. The most common... Show moreVestibular schwannomas are benign intracranial tumors which generally arise from the Schwann cells of the superior part of the vestibular portion of the eight cranial nerve. The most common symptoms accompanying vestibular schwannoma (VS) are unilateral hearing loss, tinnitus, vertigo and unsteadiness. For many years, microsurgical treatment of VS has been considered the __gold standard__. However, the treatment of VS continues to evolve with the advent of alternative treatment options such as wait and scan and stereotactic irradiation. Moreover, advances in MRI techniques have allowed for an early diagnosis and exact measurement of growth, which has led to an increased number of patients with small and minimally symptomatic tumors. As a result, the treatment of VS no longer involves life saving surgery, but prophylactic management of future morbidity. These developments have also created new insights into how vestibular schwannoma can be best treated, as it has become clear that the tumor may remain unchanged for many years. However, the treatment of VS patients still remains a matter of debate with advocates and opponents of each modality. Traditionally, the evaluation of VS treatment was performed using primary outcome measures such as mortality and morbidity. But the subject of quality of life (QoL) has increasingly become an important outcome measure in VS. QoL may provide clinicians valuable informati on that is not always Show less
