PORTEC 2

Vaginal brachytherapy versus pelvic external beam radiotherapy for patients with endometrial cancer of high-intermediate risk (PORTEC-2): an open-label, non-inferiority, randomised trial

Pubmed


Hypothesis: Vaginal brachytherapy is equally effective in prevention of vaginal cuff recurrence of endometrial cancer compared to EBRT in high intermediate risk patients.

Standard Arm: EBRT (46 Gy in 2 Gy fractions)

Experimental Arm: Vaginal brachytherapy (21 Gy in 7 Gy fractions spaced 1 week apart for HDR; 30 Gy at 50–70 cGy/h for the low dose rate; and 28 Gy at 100 cGy/h in one session for the medium-dose rate)

Design: Multicenter RCT in 19 Dutch Radiation Hospitals

Inclusion Criteria: Endometrial adenocarcinoma s/p surgery (no routine lymphadenectomy) with:

  • Age > 60 and stage IC grade ½ or IB grade 3
  • Any age, stage IIA
  • (FIGO 1988 staging)

Exclusion Criteria (outside of usual):

  • Serous or clear cell histology
  • Staging lymphadenectomy
  • Interval between surgery and RT >8 weeks
  • History of prior malignancy
  • Previous RT, hormonal therapy or chemotherapy
  • Crohn’s or UC

Primary Endpoint: Vaginal recurrence

Outcomes: 

  • EBRT: 4 vaginal recurrences (1.6%)
  • Vag Brachy: 3 vaginal recurrences (1.8%)
  • Higher rate of pelvic recurrence in Vag Brachy group (0.5% vs 3.8%, HR 8.29, p=0.02)
  • No overall survival difference (82% vs 86%; NS)


Serious Adverse Events: 

  • EBRT: Grade ½ GI toxicities 53.8%
  • VBT: Grade ½ GI toxicities 12.6% (not significant at 2 years follow up); 

Conclusion: Vaginal brachytherapy provides adequate local control to reduce risk of vaginal recurrence in high-intermediate risk endometrial cancer. It has a favorable side effect profile, with no overall survival benefit.