Objectives: To determine recurrence patterns and survival outcomes of stage II uterine papillary serous carcinoma (UPSC) patients treated by various modalities with an emphasis on carboplatin/paclitaxel-based chemotherapy (CT) +/- radiotherapy (RT). Methods: A retrospective, multi-institution study of women with stage II UPSC diagnosed from 1992 to 2006 was performed. All patients underwent comprehensive surgical staging. Treatment included observation (OBS), RT (vaginal brachytherapy, whole pelvic and/or whole abdominal therapy), or ≥ 3 cycles carboplatin/paclitaxel alone or with RT. Recurrence and survival outcomes were determined. Results: We identified 55 subjects: 10 treated with OBS, 26 with RT alone and 19 with CT +/- RT. After a median follow-up of 33 mos (range, 10-119), 20 recurrences (36%) were observed. There was an overall difference in recurrence based upon treatment (p = .013). Specifically, all CT +/- RT treated patients had a lower risk of recurrence (11%) compared to patients treated by RT alone (50%) or OBS (50%). No patients treated with both CT + RT (n = 12) experienced a recurrence. Treatment with CT was also associated with a decreased risk of recurrence on multivariate analysis (p = .015). Most recurrences were extra-pelvic (70%), occurred within 2 years (85%) and were not salvageable (84%). Five-year progression-free survival was 86% in chemotherapy-treated patients versus 41% in those not receiving chemotherapy (p = .010); overall survival was 88% in chemotherapy-treated patients versus 64% in those not receiving chemotherapy (p = .115). Conclusions: Stage II UPSC patients have a significant risk for unsalvageable, extra-pelvic recurrence. However, treatment with platinum/taxane therapy +/- RT appears to reduce this risk and is associated with improved progression free survival outcomes. © 2008 Elsevier Inc. All rights reserved.