The uterine corpus gives rise to cancers of several tissue types. Malignancies of the uterine epithelial lining can appear as glandular endometrioid, papillary serous, or clear cell histologies. Uterine papillary serous carcinoma (UPSC) comprises <10% of uterine cancers yet accounts for >20% of uterine cancerspecific deaths. 1 This less-common histologic variant is characterized by its aggressive nature and shorter overall survival compared with uterine cancer of endometrioid histology. Thus, UPSC dictates a more comprehensive approach to treatment than its endometrioid counterpart, requiring complete surgical staging and adjuvant therapy, even in patients with early-stage disease.The study by Nickels Fader et al was a retrospective analysis of outcome in 142 patients with stage I UPSC who were treated with surgery followed by observation, radiotherapy, or chemotherapy AE radiotherapy. 2 The authors reported better outcomes when adjuvant chemotherapy was used, but raised the question of whether radiation is necessary. The 142 cases were collected from 9 institutions, allowing for meaningful statistical comparisons to be made between the 3 postsurgical treatment options. Patients who were treated postoperatively with chemotherapy were found to have a lower risk of disease recurrence when compared with those treated with observation or radiotherapy alone.This analysis builds on previously published work describing the utility of adjuvant treatment for all patients with stage I UPSC, except those without residual uterine disease after complete surgical staging. To our knowledge, Kelly et al were the first to suggest that chemotherapy was not necessary for patients with stage I UPSC who were found to have no residual disease at the time of definitive surgery. 3 The formal stage of a patient's uterine carcinoma is defined surgically, based on pathologic assessment of the pelvic and para-aortic lymph nodes as well a full evaluation of the omentum. Patients at low risk of disease recurrence (ie, those who have stage I, grade 1/2 uterine carcinoma of endometrioid histology) may undergo total abdominal hysterectomy and bilateral salpingo-oophorectomy (TAH-BSO) alone, with a reported recurrence rate of only 2%. 4 However, the presence of papillary serous histology places the patient at high risk of disease recurrence, and requires comprehensive surgical resection such as that performed for ovarian cancer, including TAH-BSO, pelvic and para-aortic lymphadenectomy, and omentectomy. The necessity