Objective: Prior to 1995, in our center, patients with surgically staged endometrial cancer with greater than 50% myoinvasion (FIGO 1C) were treated with vault brachytherapy and whole pelvis (WP) radiotherapy despite negative nodes. After October 1, 1995, these patients were treated with vault brachytherapy alone. The aim of this study was to ensure that the survival and recurrence rate had not changed.
Methods: A retrospective review of Cancer Care Manitoba charts was undertaken. All patients diagnosed with endometrioid adenocarcinoma between October 1, 1995, and March 1, 2001, were reviewed. Data for all FIGO surgical stage 1 patients, and a subset of stage 1C patients, were analyzed and compared with those of a historical control group, composed of patient data previously collected in our center (1978 to 1990) [Gynecol. Oncol. 55 (1994), 51].
Results: A total of 172 patients had negative selective pelvic lymphadenectomy and FIGO stage 1 disease. Fifty-three stage 1C patients were spared WP radiotherapy. Median follow-up was 32 months. Recurrence rate in FIGO stage 1 disease was 2.3% (4/172) and for the subset 1C was 5.7% (3/53). The recurrence rate was not statistically significantly different from that of the historical control group, 3.6% for stage 1 (P = 0.562) and 7.2% for stage 1C (P = 0.51). Two- and five-year survival rates for stage 1 patients in this study were 97 and 95%, respectively. In the historical group, 2- and 5-year survival rates were 97 and 94%.
Conclusion: Whole pelvis radiotherapy can be safely omitted in patients with FIGO stage 1C endometrial cancer if nodal status is known.