Objective: To describe trends in the use of lymphadenectomy for endometrioid adenocarcinoma of the endometrium between 1998 and 2012.
Methods: A time-trend analysis was conducted using a population-based cancer registry covering 28% of the population of the United States. To quantify differences over the study period time, the frequency of lymphadenectomy and nodal metastasis among women who underwent surgical treatment of endometrioid endometrial adenocarcinoma was compared among consecutive 3- to 4-year periods. Biannual frequency of lymphadenectomy was modeled with Joinpoint regression to identify when potential changes in trends occurred and calculate annual percentage change.
Results: A total of 74,365 women who underwent surgery between 1998 and 2012 were analyzed. Frequency of lymphadenectomy increased by 4.2% annually (95% confidence interval [CI] 3.7-4.6) from 1998 to 2007, after which the frequency declined by 1.6% per year (95% CI 0.9-2.2). Between 1998-2000 and 2007-2009, the frequency of lymphadenectomy rose from 48.7% to 65.5% (risk difference 16.8%, 95% CI 15.4-18.1), the proportion of women found to have nodal metastasis increased by 1.1% (95% CI 0.4-1.7), and the frequency of negative lymphadenectomy increased by 15.7% (95% CI 14.3-17.1). The decline in frequency of lymphadenectomy after 2007 was associated a 3.1% (95% CI 2.1-4.1) decline in the rate of negative lymphadenectomy, but no change in the proportion of women found to have nodal metastasis (P=.17).
Conclusion: The frequency of lymphadenectomy in the surgical treatment of endometrioid endometrial cancer increased by 4.2% annually from 1998 to 2007 and decreased by 1.6% annually from 2007 to 2012.
Level of evidence: II.