Left insular high-grade glioma

Introduction

Surgery within the insula is associated with significant morbidity because it is adjacent to and involves critical cortical structures, white matter tracts, and cerebral vasculature. The incidence of subtotal resections for insular gliomas ranges from 62% to 100% in several series. Despite this high rate of subtotal resection, the risk of temporary and permanent deficits are 11% and 4%, respectively, in a recent meta-analysis. Insular tumors, however, are far from uniform, as some extend to the opercular surface and involve eloquent cortical and subcortical structures. In this chapter, we present a case of a large, dominant- hemisphere high-grade glioma that involves the insula and extends to the opercular surfaces.

Example case

Chief complaint: headaches and lethargy

History of present illness

A 41-year-old, right-handed, Spanish-speaking man with a history of previous biopsy of a left temporal/insular World Health Organization (WHO) grade II fibrillary astrocytoma presented with increasing headaches and lethargy. He had undergone an excisional biopsy 6 years prior of the left temporal tip with a diagnosis of a WHO grade II fibrillary astrocytoma and was lost to follow-up. Over the past 3 to 4 months, he complained of increasing headaches, lethargy, and brain imaging was concerning for disease progression ( Fig. 22.1 ).

Medications : None.
Allergies : No known drug allergies.
Past medical and surgical history : Left temporal biopsy 6 years prior for fibrillary astrocytoma.
Family history : No history of intracranial malignancies.
Social history : Landscaper, no smoking, social alcohol.
Physical examination : Awake, alert, oriented to person, place, and time; Language: intact naming and repetition in Spanish; Cranial nerves II to XII intact; No drift, moves all extremities with full strength.

	Frederick F. Lang, MD, MD Anderson Cancer Center, Houston, TX, United States	Linda M. Liau, MD, PhD, University of California-Los Angeles, Los Angeles, CA, United States	Stephen J. Price, MBBS, PhD, University of Cambridge, Cambridge, United Kingdom	Jinsong Wu, MD, PhD, Fudan University, Huashan Hospital, Shanghai, China
Preoperative
Additional tests requested	MRA fMRI Neuropsychological assessment	fMRI DTI Neuropsychological assessment DOPA-PET Possible Wada (sodium amytal) test	DTI Neuropsychological assessment	fMRI task-based BOLD DTI MRS Neuropsychological assessment
Surgical approach selected	Left fronto-temporal craniotomy with awake language mapping if possible after debulking	Left fronto-temporal craniotomy with awake language and motor mapping	Left pterional craniotomy with awake language and motor mapping and 5-ALA	Left modified pterional with asleep motor mapping and intraoperative MRI
Anatomic corridor	Temporal, temporal-opercular and possible trans-Sylvian	Temporal, temporal-opercular	Temporal, temporal-opercular	Left temporal-insular
Goal of surgery	Maximal safe resection of contrast-enhancing and FLAIR components	Maximal safe resection of contrast-enhancing and FLAIR components	Maximal safe resection of fluorescent tumor while preserving speech and motor	Maximal safe resection of contrast-enhancing and FLAIR components
Perioperative
Positioning	Left supine with 45-degree right rotations	Left supine with right rotation	Left semilateral	Left supine with 45-degree right rotations
Surgical equipment	Surgical navigation Brain stimulator Ultrasonic aspirator	Surgical navigation IOM (MEP/SSEP/ECoG) Brain stimulator Surgical microscope Weck clips	Surgical navigation Brain stimulator–bipolar and monopolar IOM (SSEP, MEP) Surgical microscope with 5-ALA Ultrasonic aspirator	Surgical navigation IOM (MEP, SSEP, phase reversal) Brain stimulator Ultrasonic aspirator Intraoperative MRI
Medications	Steroids Antiepileptics Milrinone for vasospasm	Mannitol Steroids Antiepileptics	Mannitol Steroids 5-ALA	Steroids Antiepileptics
Anatomic considerations	Sylvian fissure, vein of Labbe, MCA (M1 and M2), lateral ventricle, uncus, AF, Wernicke area, CST	MCA, lenticulostriates, Broca area, internal capsule	Language areas, AF, MCA and branches	Temporal pole, STG, MTG, mesial temporal lobe, temporal stem, striatum, IFOF, ILF, optic radiation, MCA, PCA, oculomotor nerve, choroidal fissure
Complications feared with approach chosen	Language dysfunction, motor deficit	Language dysfunction, motor deficit	Language dysfunction, motor deficit	Language dysfunction, motor deficit, hemianopia
Intraoperative
Anesthesia	Asleep-awake-asleep (if mass effect can be reduced)	Asleep-awake-asleep	Asleep-awake-asleep	General (because of mass effect)
Skin incision	Left question mark	Left curvilinear	Left question mark	Left pterional
Bone opening	Left fronto-temporal	Left fronto-temporal	Left fronto-temporal	Left fronto-temporal
Brain exposure	Left fronto-temporal	Left fronto-temporal	Left fronto-temporal	Left fronto-temporal
Method of resection	Left craniotomy with navigation guidance, open dura, assess fullness of brain, drain cyst early to provide decompression if necessary, as well as hyperventilation and head elevation, if brain relaxed then wake patient up, if brain is not relaxed then safe anterior temporal lobectomy, map temporal lobe for speech to define posterior edge of temporal lobectomy, temporal lobectomy then insular resection, dissect M2 vessels from tumor, identify superior periinsular sulcus, dissect perforators off the back of M2, remove tumor based on insular anatomy	Left craniotomy, dural tack up sutures, C-shaped dural opening based anteroinferiorly, motor strip mapping to identify primary motor cortex, awaken patient to perform language mapping to identify the Broca area and other eloquent language areas, right temporal lobectomy, enter insula from temporal operculum, decompress cyst and resect insular portions of tumor, continuous language and motor mapping, watertight dural closure	Myocutaneous flap, left craniotomy, reduce bone overlying temporal fossa, temporal lobectomy while patient asleep, superior aspect through MTG and posteriorly within tumor, subpial dissection in both planes, map for motor function with strip electrode on cortical surface and phase reversal, stimulate cortex to obtain continuous MEP, wake patient up, map language namely with picture naming with neuropsychologist in English and Spanish, complete lobectomy once language areas identified, subpial dissection to expose MCA and branches in Sylvian fissure, resect posterior margin with fluorescence and mapping, medial resection using subpial dissection for fluorescent tumor, open cyst superiorly, resect fluorescent wall of cyst, language mapping over insular cortex, once language mapping complete patient is put back asleep, careful resection between insular vessels, motor mapping of deep margins using sucker with monopolar stimulator starting at 8 mA and can lower based on depth, inspect for residual fluorescence	Surgical navigation with MRS/DTI/fMRI, left fronto-temporal craniotomy based on navigation, dural tack up sutures, dural opening, strip electrode placed for phase reversal to identify central sulcus, cortical and subcortical motor mapping, outline border of tumor with navigation, cortical incisions based on negative mapping area, subpial dissection, near the Sylvian fissure the ultrasonic aspirator is changed to tissue selection, resection along periinsular sulcus and temporal lobectomy with resection of uncus and opening into ventricle, papaverine to MCA vessels, monopolar stimulation in the subcortical space, intraoperative MRI to guide further resection
Complication avoidance	Debulk tumor prior to waking up patient, language mapping, define insular sulci, dissect M2 and its perforators from tumor, identify lenticulostriate vessels	Motor strip mapping, awake language mapping, temporal lobectomy first, temporal opercular approach to insula	Asleep motor mapping, awake language mapping, temporal lobectomy first, subpial dissection, temporal opercular approach to insula, 5-ALA	Surgical navigation with DTI/fMRI, phase reversal, cortical and subcortical asleep motor mapping, continuous MEP, papaverine to vessels, intraoperative MRI
Postoperative
Admission	ICU	ICU	Floor	ICU
Postoperative complications feared	Motor deficit, language dysfunction, visual field cut	Vasospasm of MCA vessels, language dysfunction, motor deficit	Language dysfunction, motor deficit	Motor deficit, hemianopia, aphasia, ptosis, working memory loss, emotional disorder
Follow-up testing	MRI within 24 hours after surgery	MRI within 24 hours after surgery	MRI within 72 hours after surgery	Intraoperative MRI on completion of surgery or MRI within 72 hours after surgery
Follow-up visits	10 days after surgery with neurosurgery, radiation oncology, neurooncology	2 weeks after surgery	7 days after surgery	1 month after surgery
Adjuvant therapies recommended
IDH status	Mutant–radiation/temozolomide Wild type–radiation/temozolomide	Mutant–radiation/temozolomide Wild type–radiation/temozolomide	Mutant–radiation/temozolomide Wild type–radiation/temozolomide	Mutant–radiation/temozolomide Wild type–radiation/temozolomide
MGMT status	Methylated–radiation/temozolomide Unmethylated–radiation/temozolomide	Methylated–radiation/temozolomide Unmethylated–radiation/temozolomide	Methylated–radiation/temozolomide Unmethylated–radiation/temozolomide	Methylated–radiation/temozolomide Unmethylated–radiation/temozolomide