Trends in endometrial carcinoma: experience of a single institute for four decades

To determine the current prognosis of endometrial carcinoma in Japan by analyzing long-term trends in endometrial carcinoma at our hospital.

We divided 1463 patients with endometrial carcinoma who visited our hospital between 1984 and 2022 into group 1984-1991, group 1992-1999, group 2000-2006, group 2007-2014 and group 2015-2022. Trends were determined using the Jonckheere-Terpstra and Cochran-Armitage tests. Data were analyzed using Cox regression analysis.

When group 2015-2022 was used as a reference in the univariate analysis, the hazard ratios for the other groups were <1. In particular, the hazard ratio for group 2007-2014 was 0.65 (95% confidence interval, 0.47-0.90, P = 0.009), suggesting that the prognosis of group 2015-2022 was worse than that of group 2007-2014 and seemed to be the worst among all prognoses. In multivariate analysis, the hazard ratios for each group were 1.38, 1.42, 1.88, 1.16 and 1, respectively; the group with the worst prognosis changed from group 2015-2022 to group 2000-2006 (hazard ratio, 1.88; 95% confidence interval, 1.27-2.78, P = 0.001). Age and the rate of non-endometrioid carcinoma exhibited significantly increasing trends (P < 0.001 and P < 0.001, respectively), as did the rates of serous and mixed carcinomas (P = 0.001 and 0.024, respectively). The rates of non-endometrioid carcinoma, serous carcinoma and mixed carcinoma were 19.0%, 5.5% and 3.1% in group 2007-2014 and 28.2%, 10.8% and 4.6% in group 2015-2022, respectively.

The increasing rates of non-endometrioid carcinoma-especially serous and mixed carcinoma-may be associated with the worsening prognosis of endometrial carcinoma at our institution. Careful monitoring is needed to confirm whether this phenomenon is observed throughout Japan.