Goldsmith 1994 (UCSF Meningioma RT)

Background

Retrospective single-institution (UCSF) study. N=117 meningioma patients (predominantly WHO grade I) treated with conventional EBRT after surgery 1967–1990; 72% subtotal resection (STR), 28% biopsy only. Included skull base, cavernous sinus, sphenoid wing, and convexity tumors; CT/MRI-planned RT for later cases.

Interventions and follow up

Arm A (≤52 Gy): Conventional fractionated EBRT ≤52 Gy after STR (72%) or biopsy (28%) of intracranial meningioma
Arm B (>52 Gy): Conventional fractionated EBRT >52 Gy, same population
Primary endpoint: Actuarial PFS by prescribed dose and extent of resection
mFollow up: Median 87.5 months

Results

5-yr PFS (dose >52 Gy vs ≤52 Gy): 93% vs 65%, P=.013
5-yr PFS all patients: 89%
15-yr PFS all: 74%
STR + RT 5-yr PFS: 89% (comparable to total resection alone)

Adverse events

Radiation necrosis: <5%
Visual complications: Rare
Neurocognitive effects: Not systematically reported
Long-term endocrine deficiency: Not assessed in this series

Conclusions

Post-surgical EBRT with doses >52 Gy produced 5-year PFS of 93% for meningioma, establishing the minimum effective dose threshold. Subtotally resected meningioma treated with post-op RT had PFS equivalent to gross-total resection — foundational evidence for adjuvant RT in incompletely resected meningioma.

Key Limitations

Retrospective, single-institution, non-randomized; dose comparison is observational and confounded by era/technique (older orthovoltage to later CT/MRI-planned RT). Predates modern WHO grading and molecular classification. Toxicity capture incomplete (neurocognitive, endocrine not systematically assessed).

Clinical Context

Classic series underpinning the ~54 Gy minimum dose convention for fractionated meningioma RT and the role of adjuvant RT after subtotal resection. Findings later reinforced prospectively by RTOG 0539 and EORTC 22042-26042.

References