Phase III Trial: Adjuvant Pelvic Radiation Therapy Versus Vaginal Brachytherapy Plus Paclitaxel/Carboplatin in High-Intermediate and High-Risk Early Stage Endometrial Cancer

J Clin Oncol. 2019 Jul 20;37(21):1810-1818. doi: 10.1200/JCO.18.01575. Epub 2019 Apr 17.

Abstract

Purpose: The primary objective was to determine if vaginal cuff brachytherapy and chemotherapy (VCB/C) increases recurrence-free survival (RFS) compared with pelvic radiation therapy (RT) in high-intermediate and high-risk early-stage endometrial carcinoma.

Patients and methods: A randomized phase III trial was performed in eligible patients with endometrial cancer. Eligible patients had International Federation of Gynecology and Obstetrics (2009) stage I endometrioid histology with Gynecologic Oncology Group protocol 33-based high-intermediate-risk criteria, stage II disease, or stage I to II serous or clear cell tumors. Treatment was randomly assigned between RT (45 to 50.4 Gy over 5 weeks) or VCB followed by intravenous paclitaxel 175 mg/m2 (3 hours) plus carboplatin (area under the curve, 6) every 21 days for three cycles.

Results: The median age of the 601 patients was 63 years, and 74% had stage I disease. Histologies included endometrioid (71%), serous (15%), and clear cell (5%). With a median follow-up of 53 months, the 60-month RFS was 0.76 (95% CI, 0.70 to 0.81) for RT and 0.76 (95% CI, 0.70 to 0.81) for VCB/C (hazard ratio, 0.92; 90% confidence limit, 0.69 to 1.23). The 60-month overall survival was 0.87 (95% CI, 0.83 to 0.91) for RT and 0.85 (95% CI, 0.81 to 0.90) for VCB/C (hazard ratio, 1.04; 90% confidence limit, 0.71 to 1.52). Vaginal and distant recurrence rates were similar between arms. Pelvic or para-aortic nodal recurrences were more common with VCB/C (9% v 4%). There was no heterogeneity of treatment effect with respect to RFS or overall survival among clinical or pathologic variables evaluated.

Conclusion: Superiority of VCB/C compared with pelvic RT was not demonstrated. Acute toxicity was greater with VCB/C; late toxicity was similar. Pelvic RT alone remains an effective, well-tolerated, and appropriate adjuvant treatment in high-risk early-stage endometrial carcinomas of all histologies.

Trial registration: ClinicalTrials.gov NCT00807768.

Publication types

  • Clinical Trial, Phase III
  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Brachytherapy / methods
  • Carboplatin / pharmacology
  • Carboplatin / therapeutic use*
  • Endometrial Neoplasms / drug therapy*
  • Endometrial Neoplasms / pathology
  • Endometrial Neoplasms / radiotherapy*
  • Female
  • Humans
  • Middle Aged
  • Neoplasm Staging
  • Paclitaxel / pharmacology
  • Paclitaxel / therapeutic use*
  • Pelvis / radiation effects*
  • Prospective Studies
  • Radiotherapy, Adjuvant / methods*
  • Vagina / radiation effects*
  • Young Adult

Substances

  • Carboplatin
  • Paclitaxel

Associated data

  • ClinicalTrials.gov/NCT00807768