A discordant histological risk classification in preoperative and operative biopsy in endometrial cancer is reflected in metastatic risk and prognosis

Introduction: In endometrial cancer, tissue for histological evaluation is obtained preoperatively (endometrial biopsy) and operatively (hysterectomy specimen). We investigated if a discordant risk classification based on preoperative and operative biopsy is reflected in metastatic risk and prognosis. Patients and methods: One thousand three hundred and seventy-four patients were prospectively included in a multicentre setting (Molecular Markers for Treatment of Endometrial Cancer (MoMaTEC) study). Preoperative and operative specimens were classified as high risk if non-endometrioid histology or endometrioid grade 3; otherwise low risk. Disease specific survival differences were calculated by means of Kaplan-Meier and Cox proportional hazard models. Results: Discordant risk was found in 207 (16%) cases. Lymph node metastases were detected in 7% and 23% of patients with concordant low and high risk respectively versus 14% and 20% in the discordant groups (p <0.001). Five-year disease specific survival in the discordant groups proved intermediate (75-80%) to concordant low (94%) or high (58%) risk. Both operative and preoperative biopsy high-risk results have independent prognostic impact on disease specific survival with adjusted hazard ratios of 2.4 (95% confidence interval (95% CI) 1.5-3.9) and 2.1 (95% CI 1.3-3.2) respectively by Cox analysis. Conclusions: Discordant risk in preoperative biopsy and hysterectomy identifies an intermediate group with respect to disease spread and prognosis. Preoperative biopsy results remain important also with the hysterectomy histology available. (C) 2012 Elsevier Ltd. All rights reserved