[1085] Old Versus New FIGO Staging Systems in Predicting Overall Survival in Patients with Uterine Leiomyosarcoma: A Study of 86 Cases.

Diana Lim, Wei-Lien Wang, Cheng-Han Lee, Thomas Dodge, Blake Gilks, Esther Oliva. National University Health System, Singapore, Singapore; M.D Anderson Cancer Center, Houston, TX; Vancouver General Hospital, BC, Canada; Massachusetts General Hospital, Boston

Background: Uterine leiomyosarcoma (LMS) has traditionally been staged using the FIGO system for endometrial cancer. Recently, a new FIGO staging system (modified from the AJCC soft tissue sarcoma staging system) has been proposed. We aimed to compare whether the old or new FIGO staging system is more accurate in predicting overall survival (OS) in patients with LMS.
Design: 86 patients diagnosed with uterine LMS in two tertiary institutions between 1984 and 2010 were retrospectively staged using the old and new FIGO systems. OS was calculated from the date of diagnosis to date of death or last follow up. 5 year survival rates for both groups were estimated using the Kaplan-Meier method. Median OS was also analyzed.
Results: 27 patients were downstaged and none were upstaged using the new FIGO system. Five and 4 patients with old FIGO stages 2 and 3 respectively were downstaged to stage 1 while 18 with old stage 3 were downstaged to stage 2. The median follow-up time was 23.5 months (range, 1 to 216). 30 patients (35%) died of disease.

	New FIGO Stage (No. of patients)
Old FIGO stage	1	2	3	4	Total No. Patients
1	33	0	0	0	33
2	5	0	0	0	5
3	4	18	5	0	27
4	0	0	0	21	21
Total	42	18	5	21	86

5-year OS rate (%) of patients stratified by stage according to old and new FIGO systems
	Old FIGO		New FIGO
Stage	OS Rate	95% CI	OS Rate	95%CI
1	94	86-98	76	61-88
2	50	12-88	64	39-84
3	71	50-86	100	46-100
4	54	32-75	57	34-77
Mean OS rates for old versus new FIGO Staging
	OS in months (95%CI)
Stage	Old FIGO		New FIGO
1	44.7 (28.4-60.5)		45.2 (31.9-58.5)
2	31.4 (14.8-48.1)		28.1 (18.7-37.5)
3	32.3 (21.3-43.3)		37.6 (12.4-62.8)
4	33.9 (15.3-52.5)		34.3 (15.8-52.8)

Conclusions: Neither staging system is ideal in classifying patients with uterine LMS into 4 clinically significant stages predictive of OS. Differences in OS are not significant between the two systems. Other prognostic factors should be explored and incorporated into the staging of uterine LMS to improve stratification of patients for different therapeutic regimes.
Category: Gynecologic & Obstetrics

Wednesday, March 2, 2011 1:00 PM

Poster Session VI # 184, Wednesday Afternoon