Large sized vestibular

Large sized vestibular: Management strategies and outcome : 

Large sized vestibular: Management strategies and outcome H El-Maghraby,1 C Collis,2 R Quiney,3 A Wright4 1 Neurosurgery Consultant Neurosurgeon University Hospital Coventry England, United Kingdom 2.Radiotherapy and Oncology 3.Ear, Nose and Throat Surgery Royal Free Hospital 4. Royal National Throat, Nose and Ear Hospital

INTRODUCTION : 

INTRODUCTION Management of vestibular schwannoma: Microsurgery External beam irradiation Wait & Scan But Large sized vestibular schwannoma - Microsurgery

Microsurgery : 

Microsurgery Complete tumour removal 40% -97% Tumour size Surgical expertise VII nerve preservation 37% - 80% Tumour size Extent of tumour resection Serviceable hearing less applicable in large tumours Tumour recurrence 1%-60% Extent of tumour resection

Aim of the study : 

Aim of the study Asses the extent of surgical resection with or without fractionated stereotactic radiotherapy in management of Large sized vestibular schwannomas In relation to VII nerve preservation Tumour recurrence

Large sized vestibular schwannoma : 

Large sized vestibular schwannoma Maximum Tumour Dimension (MTD) = longest measurable distance on a single image Defined as maximum tumour dimension of 30 mm or more

Extent of resection : 

Extent of resection No clear definitions in Literature Total resection (TR) Complete macroscopic resection Near total resection (NTR) is defined as capsular remnants either on facial nerve or brainstem (Kemink et al 1991) Radical subtotal resection (STR) is defined as tumour remnant, either less than 5 mm in maximum tumour dimension or 10% of initial tumour volume (either intracanalicular, adherent to facial nerve or brainstem) (Lownie & Drake 1991,El-Kashlan et al 2000) Subtotal resection (ST)

Management strategies : 

Management strategies Total resection (TR) - clear arachnoid plane - No changes in intra-operative VII monitoring - No changes in vital signs during dissection of tumour from brainstem Near total resection (NTR) - Capsular adhesions - Patients’ preference (Reduce risk VII palsy) Radical subtotal resection & Fractionated stereotactic radiotherapy (RSR & FST) - No clear neural/tumour plane - Residual tumour (intracanalicular, VII nerve or brainstem) Subtotal resection (SR) - Salvageable surgery elderly / co-morbidities with severe brainstem compression

Indications for fractionated stereotactic radiotherapy (FSR) : 

Indications for fractionated stereotactic radiotherapy (FSR) Post resection tumour residual more than 5 mm in maximum tumour dimension at 3 months MR imaging Evidence of post resection tumour recurrence on serial MR imaging

METHODS AND MATERIALS : 

METHODS AND MATERIALS 1990 – 2005 Multi-disciplinary team (Neurosurgery, ENT, Oncology) 457 new cases of all sized vestibular schwannoma 252 large sized vestibular schwannomas 218 included in the study 34 excluded, - 27 no postoperative follow / incomplete medical records - 7 neurofibromatosis

Slide 11: 

Patient population Mean age in subtotal resection (SR) is higher (p=0.003) Mean maximum tumour dimension in total resection (TR) is smaller

VII Nerve Outcome : 

VII Nerve Outcome VII nerve preservation was higher in NTR, RSR & FSR groups compared to TR group (p=0.035 and 0.028 respectively)

Tumour recurrence / regrowth : 

Tumour recurrence / regrowth 17 patients had tumour growth (11 recurrence & 6 regrowth). 6 regrowth in (SR) required no treatment other than shunt. ( Elderly & significant co-morbidity) Recurrence-free survival (months) mean 48 months (range 15-88 months) 5/11 required redo surgery 6/11 required delayed Fractionated stereotactic radiotherapy Recurrence was significantly low in Total resection (p=0.003) Recurrence was not of statistically significant difference in NTR and SRT & FRT (p=0.062)

Conclusions : 

Conclusions Total Resection is the aim Near total resection (NTR) and Radical subtotal resection with Fractionated stereotactic radiotherapy (RST & FST) achieve better VII nerve preservation and good tumour control Preserving the facial nerve, and leaving a tumour remnant, should never be considered as technical inefficiency

Slide 16: 

Thank You

Review of literature : 

Review of literature 11 had radical subtotal resection without futher radiotherapy. 2/11 (18%) had recurrence at 2yr and 3 yr VII preservation was 82% Recommendation to offer radiotherapy Our study 24 had radical subtotal resection & Fractionated stereotactic radiotherapy 1/24 (4%) had recurrence at 5yr VII preservation was 88%

Review of literature : 

Review of literature Extent of resection (No radiotherapy) on immediate VII outcome & recurrence Patients VII preservation Recurrence Total resection 26 15.4% 3% Near total resection 32 40.6% 9.4% Subtotal resection 58 46.6% 27.6% Our Study Vii preservation is significantly higher (at one year follow up) Recurrence in Near total resection same (8.9% Vs 9.4%)

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Review of literature Patients Recurrence Near total resection & Radical subtotal resection 32 10 (31%) Surgery adjuvant radiosurgery 8 no recurrence Recommendation: To Offer Radiotherapy

Postoperative Complications : 

Postoperative Complications No statistical difference in postoperative complications in all groups except hydrocephalus requiring shunt in (SR) group. 3 cases of surgery related mortalities, 2 due to cerebellar infarction, 1 due to infection