Vaginal cuff brachytherapy boost was associated with improved survival in stage II endometrial cancer

Adding vaginal cuff brachytherapy to whole pelvis radiation therapy was associated with improved overall survival in stage II endometrioid endometrial cancer.

KEY POINTS

  • This retrospective National Cancer Database study included 1,782 patients with surgically staged, node-negative, stage II endometrioid endometrial cancer diagnosed from 2010–2022. Of these, 670 received whole pelvis radiation therapy alone and 1,112 received whole pelvis radiation therapy plus vaginal cuff brachytherapy.
  • At a median follow-up of 6.5 years, adding vaginal cuff brachytherapy was associated with improved overall survival on multivariable analysis: hazard ratio 0.68 (95% confidence interval 0.55–0.83p<0.001).
  • The association remained significant after propensity score matching: adjusted hazard ratio 0.61 (95% confidence interval 0.47–0.79p<0.001).
  • Three-year overall survival was 91.7% with whole pelvis radiation therapy plus vaginal cuff brachytherapy versus 88.8% with whole pelvis radiation therapy alone. A three-year landmark analysis also favored the combined approach: hazard ratio 0.70 (95% confidence interval 0.55–0.89p=0.004).
  • The database did not capture recurrence patterns, progression-free survival, treatment-related toxicity, molecular classification, or patient-reported outcomes.

CLINICAL TAKEAWAY

A vaginal cuff brachytherapy boost may provide additional benefit after whole pelvis radiation therapy for carefully selected patients with stage II endometrioid endometrial cancer. However, the observed survival advantage comes from a retrospective database analysis and may reflect residual confounding; prospective evaluation in molecularly defined cohorts is needed before considering the finding practice-changing.

SOURCE

Advances in Radiation Oncology