Improved long-term survival of corpus cancer in Japan: A 40-year population-based analysis.

Abstract

The incidence of uterine corpus cancer has been increasing globally due to increase in obesity. However, a detailed analysis of long-term epidemiological trends of corpus cancer in Japan, where obesity is relatively minimal, has not been conducted. In this retrospective, population-based study using the Osaka Cancer Registry, we analyzed 15,255 cases of corpus neoplasia registered between 1977 and 2016. We determined the age-standardized incidence, mortality, relative survival, and conditional survival rates, and the treatment trends for corpus cancer over the last 40\u2009years in Japan. The age-standardized incidence rate of corpus cancer increased sharply in 2000-2011 (APC\xa0=\xa09.9, 95% CI: 8.4 to 11.3), whereas the mortality rate trended to a much more modest increase (APC\xa0=\xa03.3, 95% CI: 2.7 to 3.8). Compared with 1977-2000, 10-year survival rates for post-2000 cases of localized and regional cases significantly improved (from 87.7% (95%CI: 85.8 to 89.4) to 94.2% (95%CI: 92.7 to 95.7), and from 47.5% (95%CI: 43.3 to 51.6) to 64.4% (95%CI: 61.0 to 67.6), respectively). This was largely associated with the significant increase in the percentage of localized and regional patients who received chemotherapy instead of radiation as an adjuvant therapy combined to surgery (p<0.001 for both). We found that each histological type (endometrioid carcinoma, serous carcinoma, clear cell carcinoma and carcinosarcoma) has different characteristics of trend of age-standardized incidence rate, relative survival, and distribution of extent of disease. In endometrioid carcinoma, the age-standardized incidence rate increased consistently after 1990, but the rate of increase was decreasing after 1997. This article is protected by copyright. All rights reserved.