Weekly Versus Bolus Cisplatin Concurrent With Definitive Radiation Therapy for Squamous Carcinoma of the Head and Neck: A Systematic Review and Network Meta-Analysis

Abstract

The schedule of cisplatin concurrent with definitive radiation for squamous carcinoma of the head and neck remains controversial. Most institutions deliver either a high-dose "bolus" schedule once every 3 weeks or a low-dose weekly schedule. We compared these 2 schedules via a simplified network meta-analysis with a common comparator. We performed a PRISMA-concordant systematic review to identify randomized controlled trials comparing cisplatin with cetuximab for nonmetastatic, locoregionally advanced squamous carcinoma of the head and neck treated with definitive radiation. Trials incorporating primary surgery or induction therapy were excluded. Patient survival times were extracted on a per-event basis from the published curves using a digitizer and validated against published point estimates and hazard ratios (HRs). Survival was compared using random effects Cox regression under a frequentist framework. Toxicity and secondary endpoints were analyzed qualitatively. The Cochrane method assessed the risk of bias. The analysis plan was preregistered with the Open Science Foundation. Five randomized trials were identified, including 1678 patients. There was no statistical difference in overall survival between weekly and bolus regimens (HR, 0.90; 95% CI, 0.53-1.52, P = .345). This Cox model suggested that for the average patient in the cohort, the absolute difference in 5-year overall survival between weekly and bolus regimens was +1.2% (95% CI, -6.1%-+5.9%, P = .345). Secondary endpoints and toxicity were not obviously different by regimen, qualitatively. The cetuximab trials provide indirect data suggesting that the differences between cisplatin schedules are subtle.