Cause of death of patients with non-muscular invasive, non-metastatic muscular invasive and metastatic bladder cancer after diagnosis

Background: The purpose of this study was to evaluate the various causes of death among patients with non-muscular invasive bladder cancer (NMIBC), non-metastatic muscle invasive bladder cancer (non-MMIBC) and metastatic bladder cancer (MBC) after diagnosis. Methods: With the Surveillance, Epidemiology, and Final Results database, patients diagnosed with bladder cancer from 2004 to 2015 were identified. All causes of death and the standardization mortality ratio (SMR) were analyzed. Results: A total of 111,784 NMIBC, 26,546 non-MIBC and 4,678 MBC patients were identified. For NMIBC patients, 44,638 patients died during the follow-up, including 20.57% of bladder cancer, 18% of other tumors and 61.36% of non-tumor diseases. Main causes of other tumors death were cancers from lung and bronchus [n=2,860, SMR: 1.56 (1.51-1.62)], pancreas [n=506, SMR: 1.15 (1.05-1.26)], and prostate [n=442, SMR: 0.62 (0.56-0.68)]. Main causes of non-tumor deaths were diseases of heart [n=10,007, SMR: 1.15 (1.13-1.17)], chronic obstructive pulmonary disease (COPD) [n=3,153, SMR: 1.54 (1.49-1.59)], cerebrovascular diseases [n=1,704, SMR: 0.96 (0.91-1)], alzheimers [n=1,211, SMR: 0.87 (0.82-0.92)] and diabetes mellitus [n=1,047, SMR: 1.19 (1.12-1.27)]. Among the 18829 deaths in non-MMIBC patients, 62.65% patients died of bladder cancer, 11.08% of other tumors and 26.39% of non-tumor causes. Main deaths of other cancers were tumors from lung and bronchus [n=435, SMR: 1.83 (1.66-2.01)], prostate [n=192, SMR: 2.21 (1.91-2.54)]. Main causes of non-tumor death were diseases of heart [n=1717, SMR: 1.56 (1.49-1.64)], COPD [n=561, SMR: 2.18 (2.01-2.37)], and cerebrovascular diseases [n=290, SMR: 1.28 (1.14-1.44)]. Among the 4,392 deaths of MBC patients, 3,486 (79.37%) died of bladder cancer. Main cause of other deaths included diseases of heart (n=128) and prostate cancer (n=57). Conclusion: For NMIBC patients, leading causes of death were diseases of heart, COPD, lung and bronchus cancer, cerebrovascular diseases, Alzheimer's, and diabetes mellitus. Leading causes of deaths for non-MMIBE patients were bladder cancer, diseases of heart, COPD, lung and bronchus cancer, cerebrovascular diseases and prostate cancer. Main causes of death for MBC patients were bladder cancer itself. Our results of all causes of death and mortality risks provided useful information for bladder cancer patients.