• Moritz Ueberschaer, Franziska Jill Vettermann, Robert Forbrig, Marcus Unterrainer, Sebastian Siller, Anna-Maria Biczok, Jun Thorsteinsdottir, Clemens C Cyran, Peter Bartenstein, Jörg-Christian Tonn, Nathalie Lisa Albert, and Christian Schichor.
• Department of Neurosurgery, University Hospital, Ludwig-Maximilians-University Munich, Germany, German Cancer Consortium (DKTK), partner site Munich, Germany.
• Neurosurgery. 2020 Dec 15; 88 (1): 140-146.

BackgroundSurgeon's intraoperative estimation of meningioma extent of resection (Simpson Grade, SG) is widely used as a prognostic factor for recurrence. However, the validity of SG is still a matter of debate. In preoperative imaging, 68Ga-DOTATATE/PET-CT has been shown to detect meningioma tissue even more sensitively than magnetic resonance imaging (MRI).ObjectiveTo evaluate the Simpson grading within the framework of modern postoperative imaging techniques (MRI; PET-CT).MethodsAt first, patients with WHO grade I meningioma, surgical resection, and postoperative 68Ga-DOTATATE/PET-CT within 6 mo after surgery were retrospectively analyzed. Second, an analogous prospective cohort of patients with WHO grade I meningioma was investigated by comparing SG after meningioma removal with postoperative MRI and 68Ga-DOTATATE/PET-CT within 6 mo after surgery.ResultsA total of 37 patients were retrospectively analyzed. In total, 5/8 patients with SG-I and II resections showed tumor remnants according to postoperative PET-CT (SG 62.5% false negative). In the prospective cohort of 52 tumors, PET-CT displayed tracer uptake in 15/37 SG-I or II resections indicating unexpected tumor remnants (SG 40.5% false negative). MRI was false negative in 7 of these 15 cases (MRI 18.9% false negative) (P = .037). Discordant results according to PET-CT were more often found in convexity (40%) and falcine (46.7%) meningiomas than in skull base meningiomas (18.2%).ConclusionIntraoperative Simpson grading is at risk to underestimate tumor remnants, predominantly in grade I and II resections. Postoperative PET-CT improves detection rates compared to MRI. Prognostic impact of postoperative meningioma remnants according to PET-CT needs to be investigated prospectively.Copyright © 2020 by the Congress of Neurological Surgeons.

26 keywords...

hide…