Abstract
Endometrial cancer (EC) is the most common gynecologic cancer in the United States. A majority of new cases are diagnosed as low-grade International Federation of Gynecology and Obstetrics (FIGO) Stage I, with a recurrence risk cited as less than 9 % in the first 2-3 years post-treatment. In this case series, we present three unique cases of patients with FIGO 2009 Stage I EC who all went on to present with pelvic colonic recurrences years after their initial treatment, two of the patients outside of the 5-year standard surveillance period. These presentations are described in the context of the available literature on EC colonic recurrence. A review of the literature suggests a previously cited association between endometriosis and unusual recurrence locations may not be as important of a risk factor as previously considered, as most of the cases in the series had no clinical or pathologic history of endometriosis. In addition, most of the included cases did not report a history of endometriosis and 60% of the cohort had received postoperative adjuvant radiation and still went on to experience locoregional recurrence. Further study on the associations between endometriosis, MMR status and EC recurrence, particularly for uncommon anatomic recurrence sites, are warranted to ensure appropriate and timely treatment.