Table 3: Some important randomized trials comparing external beam radiation therapy to observation or vaginal brachytherapy alone.

Treatment comparisonLocal recurrence rate5-year OSDistant recurrence rateG3/4 toxicity

PORTEC-1 EBRT versus observation 4% versus 14% ( ) 81% versus 85% ( ) 8% versus 7% 2% versus 0.002%
GOG99 EBRT versus observation 3% versus 12% ( ) 92% versus 86% ( ) 5% versus 6% 5% versus 0.5%
PORTEC-2 EBRT versus vaginal brachytherapy alone 2.1% versus 5.1% ( ) 80% versus 85% ( ) 6% versus 8% 2% versus <1%

EBRT—external beam radiation therapy, OS = overall survival.