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Rapid review note

Journal Club is a rapid, AI-assisted appraisal layer. It highlights study design, effect estimates, and practice relevance, but it is still a briefing, not a replacement for the paper.

For education only. Not medical advice.

Paper snapshot

Rapid study overview

Open paper

DOI

10.1001/jama.2017.18718

PMID

29260225

PICO

Population

695 patients with glioblastoma who had completed concomitant radiochemotherapy after resection or biopsy

Intervention

TTFields (≥18 hours/day) plus maintenance temozolomide

Comparator

Maintenance temozolomide alone

Outcomes

Progression-free survival, overall survival, adverse events

Design

Type

Randomized clinical trial

Randomized

Yes

Multicenter

Yes

Blinded

Open-label

Follow-up

Through December 2016 (median time from diagnosis to randomization 3.8 months)

Primary endpoint

Progression-free survival from randomization (tested at α=0.046)

Secondary endpoints

Overall survival (tested hierarchically at α=0.048)
Adverse events

Practice impact

What this means

This phase III trial shows TTFields plus temozolomide improves median PFS by 2.7 months and OS by 4.9 months compared to temozolomide alone in glioblastoma. The open-label design and industry involvement require consideration, but the survival benefit supports TTFields as an option for motivated patients who can tolerate device use.

Bottom line

TTFields plus temozolomide improves both PFS and OS compared to temozolomide alone in newly diagnosed glioblastoma after radiochemotherapy

Strength of evidence

moderate

Recommendation

consider change

Why it matters

Randomized phase III trial with significant survival benefit
Open-label design and industry involvement moderate confidence
Requires patient selection for device tolerance

What would change my mind

Long-term quality of life data showing net benefit
Cost-effectiveness analysis in real-world settings
Replication in independent non-industry trial

Critical appraisal

How strong is the paper?

Methods critique

Risk of bias

Open-label design introduces performance and detection bias; sponsor involved in design, conduct, analysis, and manuscript preparation

Confounding

Randomization 2:1 may affect balance; baseline characteristics not fully detailed in excerpt

Missing data

92% completion rate (637/695); 8% attrition acceptable

Multiplicity

Hierarchical testing of OS after PFS; appropriate control of type I error

Notes

Industry-funded with sponsor involvement in multiple aspects
Open-label may affect patient-reported outcomes and progression assessment

Stats check

NNT

Not reported directly; based on survival curves, approximately 9-10 for 1-yea...

Effect sizes

HR 0.63 (95% CI 0.52-0.76) for PFS
HR 0.63 (95% CI 0.53-0.76) for OS

Absolute effects

Median PFS: 6.7 months vs 4.0 months
Median OS: 20.9 months vs 16.0 months

Concerns

Hazard ratios identical for PFS and OS suggests similar treatment effect across time
Open-label may influence progression assessment

External validity

Who it applies to

Glioblastoma patients who have completed standard radiochemotherapy and are candidates for maintenance temozolomide

Who it does not

Patients with poor performance status, inability to use device ≥18 hours/day, or contraindications to temozolomide

Generalizability notes

83 centers internationally
Median age 56 years, 68% male
Requires patient commitment to device use and skin care

Evidence trace

Source trace and metadata

Citations (3)

claim_id

methods_critique.risk_of_bias

locator

p. 2307 Methods

quote

randomized, open-label trial

claim_id

stats_check.effect_sizes

locator

p. 2308 Results

quote

HR, 0.63; 95% CI, 0.52-0.76

claim_id

practice_impact.bottom_line

locator

p. 2308 Results

quote

median overall survival was 20.9 months in the TTFields-temozolomide group vs 16.0 months in the temozolomide-alone group

Metadata

Generated at

2026-03-06T13:41:29.251Z

Version

top 100 cited in past 20 years