Baseline risk of recurrence in stage I–II endometrial carcinoma

OBJECTIVE: Though there are no evidences that postoperative therapy improves overall survival (OS) in stage I–II endometrial carcinoma, many women receive postoperative radiation or chemotherapy. This study aimed to investigate the baseline risk of recurrence after complete resection without any adjuvant therapies and to suppose the validity of postoperative therapy for stage I–II endometrial carcinoma. METHODS: Charts for patients with stage I–II endometrial carcinoma who underwent operation without postoperative therapy between January 2005 and December 2011 were retrospectively reviewed and the baseline risk of recurrence and prognosis were assessed. Risk classifications were performed according to European Society for Medical Oncology (ESMO) clinical practice guidelines and Japanese guideline written by Japan Society of Gynecologic Oncology Group. RESULTS: Among 374 patients who underwent complete resection, 311 were evaluable. Five-year recurrence rates by ESMO and Japanese were 2.6% and 3.1% in low-risk, 9.2% and 6.6% in intermediate-risk and 13.5% and 13.8% in high-risk group (p=0.003 and 0.015, respectively). High-risk group had worse OS compared with low- and intermediate-risk groups (5-year OS, low: 97.9% and 97.6%, intermediate: 97.9% and 98.8%, and high: 89.5% and 87.5%; p=0.003 and 0.008, respectively). Independent predictive factors of recurrence were age over 60 years, type 2 (estrogen-independent) and peritoneal cytology. CONCLUSION: ESMO and Japanese risk classification similarly stratify the baseline risk of recurrence. Patients with stage I–II endometrial carcinoma, especially low- and intermediate-risk diseases, have low recurrence rate and favorable OS, and the benefit of postoperative therapy might be small.