Patterns and trends of mortality from metastatic colorectal cancer in Shanghai, China from 2005 to 2021: a population-based retrospective analysis.

Purpose: Metastatic colorectal cancer (mCRC) is the leading cause of CRC deaths, however, the relative epidemiological research was insufficient. We aimed to analyze the patterns and trends of mortality of mCRC in Shanghai with a more complete system for monitoring the cause of death of the population and find potential methods to reduce the burden of CRC in China.

Methods: Mortality data from 2005 to 2021 of mCRC deaths were obtained from the mortality registration system in Shanghai. We analyzed the crude mortality rates, age-standardized mortality rates, and rates of years of life lost (YLL rates) of mCRC. In addition, the trends were quantified using Joinpoint Regression software.

Results: A total of 4,386 mCRC deaths were included, with 1,937 (44.16%) liver metastases and 1,061 (24.19%) lung metastases. The crude mortality rate and age-standardized mortality rate of mCRC were 9.09 per 10 person-years and 3.78 per 10 person-years, respectively. The YLL was 50,533.13 years, and the YLL rate was 104.67 per 10 person-years. The overall annual crude mortality rate of mCRC increased by 1.47% (95% CI 0.28-2.68%, P < 0.001) from 2005 to 2021. The crude mortality rate of mCRC increased by 3.20% per year (95% CI 1.80-4.70%, P < 0.001) from 2005 to 2013, but the trend of mortality growth remained stable from 2013 to 2021. The YLL rates remained stable between 2005 and 2021.

Conclusions: Population aging was the most likely factor responsible for the increase in CRC mortality in Pudong. Physical examinations and screenings for the elderly were possible reasons for reducing the burden of CRC in fast-growing regions.