Adjuvant therapy in stage III endometrial cancer confined to the pelvis

To review outcomes of patients with stage III endometrial cancer confined to the pelvis treated with adjuvant pelvic radiotherapy (RT) or sequential chemoradiotherapy (CRT).

Between 1990 and 2012, 144 patients diagnosed with stage IIIA, B or C1 endometrial cancer were treated in our institution. All were treated with total hysterectomy, bilateral salpingo-oophorectomy ± lymph node dissection. Post-operatively, 67 patients received adjuvant RT alone, 37 CRT, 21 chemotherapy alone and 19 had no adjuvant therapy. This analysis focuses on the 104 patients treated with RT or CRT.

The median follow-up was 61 months. Forty-six patients (44%) were stage IIIA, 6 (6%) were stage IIIB and 52 (50%) stage IIIC1. The 5-year overall survival (OS), disease-free survival (DFS) and disease-specific survival (DSS) for patients treated by RT alone vs. CRT were, respectively, 67% vs. 61% (p = 0.55); 67% vs. 51% (p = 0.35); and 76% vs. 65% (p = 0.21). Grade 3 disease was an independent predictor for worse OS (HR = 6.01, p = 0.001), DFS (HR = 3.16, p = 0.03), and DSS (HR = 3.77, p = 0.02). In patients with grade 3 disease (n = 49), the 5-year OS was superior for the CRT (42% vs. 56%, p = 0.007).

In patients with stage III endometrial cancer confined to the pelvis, the addition of adjuvant chemotherapy with RT significantly improved OS in grade 3 disease. Grade 3 histology is a strong predictor for poor outcome. Further randomized studies aiming specifically at stage III disease are warranted.