Main Session
Sep 29
PQA 03 - Central Nervous System, Professional Development/Medical Education

2671 - Progression-Free Survival in Grade 2-3 Meningiomas: A Retrospective Analysis of Surgical and Radiotherapy Treatment Approaches at One Institution

08:00am - 09:00am PT
Hall F
Screen: 3
POSTER

Presenter(s)

Fereshteh Talebi, MD - Weill Cornell Medical College, New York, NY

F. Talebi1, S. Bogdan2, F. Gregucci3, L. Muller3, R. Ramakrishna4, R. S. Magge4, P. Stieg4, J. Ivanidze5, D. Trick1, M. Patel1, S. C. Formenti6, P. Pagnini7, and K. Beal1; 1Weill Cornell Medical College, New York, NY, 2Florida State University College of Medicine, Tallahassee, FL, 3Department of Radiation Oncology, NewYork-Presbyterian/Weill Cornell Medicine, New York, NY, 4Weill Cornell Medical College/NewYork-Presbyterian Hospital, New York, NY, 5Department of Radiology, Weill Cornell Medical College/NewYork-Presbyterian Hospital, New York, NY, 6Cornell, New York, NY, 7Weill Cornell Medicine, New York, NY

Purpose/Objective(s): Report progression-free survival (PFS) rates in pathologically proven WHO Grade 2 and Grade 3 meningiomas treated with surgery and/or radiation (RT).

Materials/Methods: We conducted a retrospective chart review of 298 patients with meningiomas who were seen between 2016- 2023. This report focuses on 143 who had a biopsy confirming Grade 1 in 96, Grade 2 in 44, and Grade 3 in 3 subjects. Data on treatment modalities, including surgery, RT, and observation, were retrieved from the electronic medical record, and progression data were analyzed using Kaplan-Meier survival curves.

Results: Among pts with pathologically assessed meningiomas grade 2 and 3 meningiomas, most were female (27 female; 20 male); median age at diagnosis was 60.5 years. The Kaplan-Meier median PFS was 42.2 months (95% CI: 29.0-65.4). The rate of PFS at Year 1, Year 2, and Year 5 were 84.9% (95% CI: 70.8-92.5), 69.2% (95% CI: 53.6-80.5), and 36.1% (95% CI: 21.6-50.8), respectively. The table summarizes the clinical data of the grade 2 and 3 pts.

Conclusion: Patients in the above cohort with Grade 2 and 3 meningiomas had a median PFS of 42.2 months, compared to 78.7 months for those of presumed mixed grade (non-biopsy proven). Grade 2 meningiomas had better PFS outcomes with surgery and adjuvant radiotherapy vs surgery alone. However, recurrence rates were still high for all. Radiation target volumes, fractionation, and dose will be presented, as well as a pathologic analysis to predict which tumors are more likely to recur and help optimize treatment.

Abstract 2671 - Table 1

WHO Grade

Initial Treatment (Number of Pts)

PFS

(Months)

Progression Site (Original site (O.S) / Marginal/ Distant)

Treatment at

first progression

Subsequent Progression

Grade 3

(n=3)

Surgery + Adjuvant Fractionated RT (1) 32.72 3(O.S) 2 received Definitive RT,

1 received surgery +RT
2 had 2ndprogression 1 had 3rd progression
Observe (2)

Grade 2

(n=44)

Definitive Surgery (14)

24.48

9 (O.S),

1 Marginal, 2 O. S+ Marginal

1 had surgery (no further progression),

1 had surgery + RT (progressed),

9 had definitive RT (SBRT: 4, SRS: 2, Fractionated RT: 1, Unknown RT regimen: 2) (3 progressed)

4 had 2nd progression (3 (O.S),

1 Distant)

1 had 3rd progression

Surgery + Adjuvant RT (Fractionated RT: 14, SBRT: 7, SRS: 3 - one with a 2nd lesion in the fractionated RT group) (23)

72.36

15 Fractionated RT: 6 O.S

3 received definitive RT (SRS: 1, SBRT: 1, Fractionated RT: 1)

2 had 2nd progression

1 had 3rd progression

7 SBRT: 3 O.S,

1 Marginal

3 received SRS

2 had 2nd progression and

1 had 3rd progression

3 SRS: 1 O. S

1received SBRT

1 had 2nd progression

Observation after biopsy (4)

16.44

4(O.S)

3 had surgery + RT (Fractionated: 2, SBRT: 1), 1 had surgery

No further progression

Definitive RT after biopsy (3) (1 Fractionated RT,2 SRS)

83.76

3(O.S)

1 had SBRT

2 had SRS

All had 2nd progression,

1 had multiple recurrences