Introduction/Background In the COVID-19 era, waiting list for surgery is longer gynecological-oncological units were forced to delay oncological surgery, especially endometrial cancer (EC), due to its good prognosis. The aim of this study is to evaluate the impact of delay in the oncological outcomes of these patients.

Methodology Retrospective analysis of all women with EC treated in the 1st Department of Obstetrics & Gynecology AUTh at ‘Papageorgiou’ Hospital, from 2012 – 2019. Delay was calculated as the time interval form the day of first examination in the outpatient clinic and the day of surgery, and a cut-off point at 8 weeks was set. Patient and tumor characteristics, treatment options and follow-up information were collected. Primary outcomes were the need of adjuvant treatment and survival rates.

Results 259 patients met the inclusion criteria. Based on the 8-week cutoff point patients were divided into two groups: 119 underwent surgery up to 8-weeks (group A) and 140 over 8-weeks (group B). There was no statistical difference in the FIGO Stage or the pre-operative CA125 level between the two groups, but patients in group A were younger, with lower BMI and less comorbidities. Furthermore, patients in group B had a significantly higher probability of receiving pelvic radiation with or without brachytherapy (p=0.005342), but no difference was detected in hospital stay, ICU admittance or surgery duration. Concerning survival rates, there was a statistical difference in disease-free (p=0.0312), but no difference was found in overall survival (p=0.146).

Conclusion Delaying EC surgery over 8 weeks may not have an impact on the mortality of the patients, but increases the need of adjuvant pelvic radiation with or without brachytherapy and the recurrence rates. As a result, patients experience more side effects which subsequently worsen their quality of life.