Analysis of breast cancer cases according to county-level poverty status in 3.5 million rural women who participated in a breast cancer screening program of Hunan province, China from 2016 to 2018.

The Hunan provincial government has implemented a free breast cancer screening program for rural women aged 35 to 64 years from 2016, under a 2015 policy aimed at of poverty eradication and improving women's health in China. However, there has been no population study of the breast cancer screening program in China to date, especially considering exploring differences related to the area's poverty status. We explored differences in risk factors, clinical examination results, and clinicopathological features among breast cancer patients in poor compared with non-poor counties in rural areas of Hunan province from 2016 to 2018 using χ and Fisher's exact test, and multivariate logistic regression analysis. A total of 3,151,679 women from rural areas participated in the screening program, and the breast cancer prevalence was 37.09/10. Breast cancer prevalence was lower in poor (29.68/10) than in non-poor counties (43.13/10). There were differences between breast cancers in poor and non-poor counties in terms of cysts, margins, internal echo, blood flow in solid masses in the right breast on ultrasound examination, lump structure in mammograms, and clinicopathological staging and grading in pathological examinations. Breast cancer in poor counties was more likely to be diagnosed at later stages as determined by ultrasound, mammography, and pathological examinations. Furthermore, indexes of the breast screening program including early detection, prevalence, pathological examination, and mammography examination were lower in poor compared with non-poor counties. Multivariate logistic regression analysis showed that education, ethnicity, reproductive history and the year 2017 were associated with an increased risk of breast cancer in poor counties (odds ratio >1, P < .05). In conclusion, women in poor areas were more likely to be diagnosed with breast cancer at a later stage compared with women in non-poor areas. Women in poor areas of Hunan province should therefore have better access to diagnostic and clinical services to help rectify this situation.