Knowledge of a cancer diagnosis is a protective factor for the survival of patients with breast cancer: a retrospective cohort study

BACKGROUND: The health burden of breast cancer is rising in China. The effect of informed diagnosis on long-term survival is not fully understood. This retrospective cohort study aims to explore the association between early informed diagnosis and survival time in breast cancer patients. METHODS: A total of 12,327 breast cancer patients were enrolled between October 2002 and December 2016. Potential factors, including knowing the cancer diagnosis status, sex, age, clinical stage, surgery history, grade of reporting hospital and diagnostic year were, analyzed. We followed up all participants every 6 months until June 2017. Propensity score matching (PSM) was used to balance the clinicopathologic characteristics between patients who knew their diagnosis and those who did not. RESULTS: By June 2017, 18.04% of the participants died of breast cancer. Before PSM, both the 3-year and 5-year survival rates of patients who knew their cancer diagnosis were longer (P < 0.001). After PSM, the above conclusion was still established. By stratified analysis, except for the subgroups of male patients and stage III patients, patients who knew their diagnosis showed a better prognosis in all the other subgroups (P < 0.05). Cox regression analysis showed that knowing a cancer diagnosis was an independent risk factor for survival in breast cancer patients (P < 0.001). CONCLUSIONS: Being aware of their cancer diagnosis plays a protective role in extending the survival time of breast cancer patients, which suggests that medical staff and patients’ families should disclose the cancer diagnosis to patients in a timely manner. Further prospective studies need to be made to validate our findings. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12885-021-08512-1.