Vestibular Schwannoma: spontaneous tumor involution

Spontaneous shrinkage of vestibular schwannoma with the recovery of impaired hearing: A case report and literature review

Background

Sporadically occurring vestibular schwannomas (VSs) are the most frequent tumors in the cerebellopontine cistern and internal meatus and are commonly associated with hearing loss. These tumors have demonstrated spontaneous shrinkage rates of 0-22%; however, the relationship between tumor shrinkage and changes in hearing remains unclear.

Case Description

We report a case of a 51-year-old woman with a diagnosis of a left-sided VS and accompanying moderate hearing loss. The patient was treated with a conservative approach for 3 years, and the tumor showed a regression along with an improvement in her hearing ability during the yearly follow-ups.

Conclusion

The spontaneous shrinkage of a VS along with an associated improvement in hearing is a rare phenomenon. Our case study may support that the "wait and scan" approach is an alternative option for patients with VS and moderate hearing loss. Further investigations are needed to understand spontaneous VS regression and hearing changes.

Decision Making in the Wait-and-Scan Approach for Vestibular Schwannomas: Is There a Price to Pay in Terms of Hearing, Facial Nerve, and Overall Outcomes?

BACKGROUND

The wait-and-scan modality has emerged as an important strategy in the management of vestibular schwannoma (VS) as it has been demonstrated that many tumors grow slowly or do not show any growth over long periods.

OBJECTIVE

To analyze long-term outcomes of wait-and-scan in the treatment of patients with VS, discuss the factors contributing to the decision making, determine the inherent risks of the policy, and compare our results with literature.

METHODS

In total, 576 patients with sporadic unilateral VS who were managed with wait-and-scan were reviewed retrospectively. Of these, a subset of 154 patients with 5-yr follow-up was separately analyzed. The tumor characteristics including patterns of growth, rate of growth, hearing outcomes, and likely factors affecting the above parameters were analyzed.

RESULTS

The mean period of follow-up was 36.9 ± 30.2 mo. The mean age was 59.2 ± 11.6 yr. Thirteen different patterns of tumor growth were observed. Eighty-four (54.5%) of 154 tumors with 5-yr follow-up showed no growth throughout 5 yr. Fifty-six (36.4%) tumors showed mixed growth rates. Only 57 (37%) patients had serviceable hearing at the start of follow-up, but 32 (56.1%) maintained it at the end of follow-up. One hundred fifty (26%) of the 576 patients who failed wait-and-scan had to be taken up for surgery.

CONCLUSION

While there may be no price to pay in wait-and-scan as far as hearing is concerned, this may not be the case for facial nerve outcomes, wherein the results may be better if the patients are taken earlier for surgery.

Spontaneous Shrinkage of Cystic Acoustic Neuroma: A Case Report

BACKGROUND

Cystic acoustic neuromas typically present with more rapid growth and shorter symptomatic periods when compared to solid tumors.

CASE PRESENTATION

We present the case of a 70-year-old male patient with unilateral sensorineural hearing loss, frequent falls, and worsening ataxia. Magnetic resonance imaging (MRI) confirmed a 33.9 cm³ cystic acoustic neuroma with mass effect on the brainstem and cerebellum. Subsequent MRI scans revealed tumor measurements of 38.2 cm³, 37.6 cm³, 23.8 cm³, and 14.3 cm³ in size at 3, 6, 9 and 15 months after initial presentation, respectively.

CONCLUSION

Spontaneous tumor regression was accompanied with reduced mass effect on neighboring structures and improved symptoms. Due to their unpredictable growth patterns, early surgical resection has been recommended for cystic acoustic neuromas. However, we present the case of a patient with spontaneous tumor involution following conservative management. Further research on the growth patterns of cystic schwannomas is imperative in order to properly counsel patients and improve treatment strategies.

Spontaneous shrinkage of vestibular schwannoma

Background:

“Watch, wait, and rescan” (WWR) has an established place as a successful management option for a significant proportion of vestibular schwannomas (VS) as an alternative to microsurgical removal or stereotactic radiotherapy. VS may grow slowly and continuously, followed by stagnation or even shrinkage. We present two case reports of spontaneous shrinkage of VS along with a review of the literature.

Case Description:

A 29-year-old female presented with a progressive history of visual blurring and intermittent diplopia over 2 months. A 29 mm of maximum intracranial diameter (ICD) VS with secondary obstructive hydrocephalus was diagnosed. The patient underwent a ventriculo-peritoneal shunt with resolution of her symptoms and opted for initial WWR management. Interval scanning between 2007 and 2014 showed progressive reduction in the maximum ICD together with reduction in the degree of central tumor enhancement. Maximum ICD at most recent follow up was 22 mm. A 28-year-old female was referred with right sensorineural deafness. A right VS of maximum ICD of 27 mm was diagnosed. Initial WWR management was planned after discussion. Serial imaging showed an initial increase in the size of the tumor followed by progressive reduction in size. The most recent follow up showed a maximum ICD of 20 mm.

Conclusion:

Early WWR management can be associated with spontaneous shrinkage of VS over time. Prospective clinical study of larger numbers of such cases using the UK VS database may help to identify predictive factors for the spontaneous regression of VS.

Traumatic neuroma of the mandible: A case report with spontaneous remission

Traumatic neuroma is a well-known disorder involving peripheral nerves, which occurs following trauma or surgery. The lesion develops most commonly in the soft tissues of the mental foramen area, lower lip and tongue. Intra-osseous lesions arising in jawbones are very uncommon. In this paper, we report a new case of an intra-osseous traumatic neuroma, discovered incidentally on a panoramic radiograph obtained for orthodontic documentation. In addition, the case herein described developed spontaneous remission, a situation not previously reported in the literature. Finally, we discuss relevant demographic, clinical, microscopic, immunohistochemical and treatment aspects of traumatic neuromas.

Key words:Amputation neuroma, traumatic neuroma, mandible, spontaneous remission.

Spontaneous tumour shrinkage in 1261 observed patients with sporadic vestibular schwannoma

Objective:

To determine the rate of spontaneous tumour shrinkage in a group of patients with sporadic vestibular schwannoma managed with a ‘wait and scan’ approach.

Patients:

All patients with a unilateral cerebello-pontine angle tumour resembling a vestibular schwannoma were registered prospectively in a national database in Denmark. Patients registered with tumour shrinkage were identified and all computed tomography and magnetic resonance imaging scans retrieved, re-evaluated and related to the clinical data.

Results:

Of 1261 observed patients, 48 displayed spontaneous shrinkage (3.81 per cent). Mean absolute shrinkage was 6.25 mm, equivalent to 52.1 per cent. Absolute shrinkage correlated with tumour size and follow-up period, whereas relative shrinkage was significantly greater for tumours which were purely intrameatal at diagnosis. There was no correlation between age and the degree of shrinkage.

Conclusion:

Four per cent of sporadic vestibular schwannomas shrink spontaneously. These findings substantiate the ‘wait and scan’ strategy for tumours with a largest extrameatal diameter of up to 20 mm.

Vestibular schwannoma of oscillating size: A case report and review of literature

Background:

Vestibular schwannomas are benign brain tumors arising from the 8th cranial nerve with a varying natural history. Various reports have described discernable growth patterns for these tumors. However, growth predictability remains low because of slow and indeterminate changes over time with follow-up reports not usually exceeding 3 years. Our report describes the long-term follow-up of an unusual cystic schwannoma with growth patterns prior to and following treatment, adding valuable information to the variable natural history and outcome of these infrequent tumors.

Case Description:

A 68-year-old gentleman presented with a left-sided cystic vestibular schwannoma, initially managed conservatively. Imaging revealed wide variations in the size of his tumor over a period of 3 years. He was finally treated with Gamma Knife radiosurgery, and at 1 year following treatment shows tumor shrinkage with a change in tumor morphology.

Conclusion:

To our knowledge, the present case represents the first instance of a schwannoma showing wide fluctuations in tumor size and morphology over a period of time, with a good response to radiosurgery. We emphasize in this report that there is no “one size fits all” treatment paradigm for these tumors and each patient requires individualized care and intervention, taking into account their differing natural histories.