Thalamic gliomas and their surgical strategy: a systematic review

Abstract INTRODUCTION Until recent decades, thalamic gliomas had been considered largely inoperable. These lesions are deep-seated and surrounded by vital structures. However, as technology and imaging modalities have improved, so have treatment modalities. Currently, a range of surgical approaches are used, partially dependent on the location of the lesion; although no consensus has been reached regarding optimal surgical management. OBJECTIVE To conduct a systematic review of the literature to describe the current surgical outcomes of adult thalamic gliomas. METHODS Four databases were searched with keywords “‘thalamic glioma’ AND ‘surgical intervention’ OR ‘thalamic glioma’ AND ‘surgical treatment’” for articles assessing surgical techniques of adult thalamic glioma resection. Our systematic review was reported in accordance with the PRISMA guidelines. 793 full-text studies were assessed for eligibility. Ultimately, 14 studies were included. RESULTS The mean age was of 33.57 years (18-83). In 479/507 cases the surgical strategy used was described. The transcortical approach was the most utilized (37.8% of cases). The remaining cases employed transventricular (23.8%), transcallosal (22.8%), and trans-sylvian transinsular (2.92%) approaches, among others. Gross total resection (GTR), subtotal resection (STR), and partial resection were achieved in 36.7%, 47.4%, and 15.9%, respectively. New temporary postoperative deficits were observed in 57/507 patients and new permanent deficits in 56/507 patients. There were 18 total perioperative deaths reported. The degree of morbidity across approaches was recorded in just one study, where no significant difference was found. The mean overall survival of adult patients after surgery ranged from 11.5 to 27.39 months across studies. CONCLUSION There is a lack of statistically strong data that addresses which surgical approach causes less morbidity and allows a better surgical resection for thalamic gliomas. Ultimately, surgical resection of adult thalamic gliomas can increase overall survival but at the risk of operative morbidity. Transcortical approaches appear to carry a greater overall survival