Improved Outcome of High-Grade, Early 1-Stage Endometrioid Endometrial Carcinoma With Adjuvant Chemotherapy and Radiotherapy: Comparison of 2 Treatment Strategies.

OBJECTIVE: Patients with high-grade endometrioid endometrial carcinoma have a high risk of recurrence, even in early stage. To determine the benefit of a more aggressive adjuvant treatment approach, different treatment strategies of 2 referral centers were compared.

MATERIALS AND METHODS: Outcome of all patients with International Federation of Gynecology and Obstetrics IB and II high-grade endometrioid endometrial carcinoma treated between 2008 and 2012, at the Gynecological Oncology Center South (GOCS) were compared with patients treated at the British Columbia Cancer Agency (BCCA). All patients underwent primary surgical treatment. Adjuvant treatment consisted of radiotherapy dependent on final pathology (GOCS), or adjuvant chemotherapy and pelvic radiotherapy (BCCA).

RESULTS: A total of 116 patients were treated at the GOCS (n = 61) and BCCA (n = 55). Patient cohorts were comparable for clinicopathological factors, except for age at diagnosis and lymphadenectomy. Radiotherapy was applied in 70.5% at the GOCS compared with 100% at the BCCA. All BCCA patients received chemotherapy compared with 3.3% at GOCS. The BCCA treatment strategy resulted in a significant reduced recurrence rate when compared with GOCS, 10.9% and 36.1%, respectively. There was no significant difference in the recurrence rate between patients with (n = 48) and without a lymphadenectomy (n = 68). Yet, numbers are relatively low. Because most recurrences were distant 78.6% (22/28), adjuvant chemotherapy resulted in reduced disease-related mortality.

CONCLUSIONS: Adjuvant chemotherapy and radiotherapy in early-stage high-grade endometrioid endometrial carcinoma results in improved disease-specific and overall survival compared to radiotherapy alone. Yet, due to the relatively low numbers, validation of these findings is needed in large prospective trials.