Session Item

The international PORTEC-4a trial was the first trial to incorporate molecular factors in decision making on adjuvant treatment for women with early stage high-intermediate risk endometrial cancer (HIR-EC). For patients allocated to the intervention arm, adjuvant treatment was based upon a molecular-integrated risk profile. The present analyses were performed to compare health-related quality of life (HRQL) and adverse event (AE) rates between the treatment arms in the first 6 months after randomisation.

Patients with HIR-EC were randomised (2:1) between individualised treatment based upon a molecular-integrated risk profile or standard vaginal brachytherapy (VBT). In case of a favourable profile, adjuvant treatment was omitted. Those with an intermediate profile received VBT while those with an unfavourable risk profile received pelvic radiotherapy (EBRT). HRQL was assessed with the EORTC-QLQ C30 and EN24 module at baseline, after treatment and 6 monthly after randomisation. AE were graded using the CTCAE v4.0. Analyses were performed on the per-protocol population. Prevalence of toxicity was calculated at each timepoint and compared using Fisher’s exact test. Analysis of HRQL was done according to the EORTC guidelines. Symptoms rated as “quite a bit” or “very much” were considered ‘severe’. A 2-sided p<0.01 was considered statistically significant, and p<0.05 reported as a trend.

Between 2012 and 2021, 563 evaluable patients were included, 367 in the molecular arm vs 196 in the standard arm, see figure 1. In 46.7% of patients in the molecular arm adjuvant treatment was omitted. Grade ≥2 AE were reported in 59 patients at completion of treatment: 41 (11.4%) in the interventional arm vs 18 (8.9%) in the standard arm (p=0.39); at 6 months, this was 44 (12.2%) vs 22 (10.9%), p=0.36. Grade 3 AE were reported for 4 patients (3 in the molecular arm and 1 in the standard arm) at treatment completion, and for 8 (4 vs 4) at 6 months. There were no grade 4 or 5 AE. During treatment all grade 3 AE were genitourinary or vaginal, whereas at 6 months only 1 was related to treatment. 94.7% completed HRQL assessment at baseline, 81.0% during treatment and 82.2% at 6 months. No significant differences between the two arms were found for physical functioning (p=0.31) and global health status (p=0.10). Social and role functioning improved over time in both arms (p<0.001). A trend for better role functioning over time was seen for patients treated according to their molecular profile compared to standard VBT (p=0.014).

Use of adjuvant treatment was greatly reduced by individualised treatment in the molecular arm of the PORTEC-4a trial. In the first 6 months no significant difference in early toxicity and HRQL were found between molecular-based adjuvant treatment and standard brachytherapy, while a strong trend for better role functioning after individualised treatment was observed.