The Impact Of Prior Cancer On Survival Of Prostate Cancer Patients

Background: Prostate cancer is the second most common malignant tumors for male patients worldwide.Among patients with prostate cancer,whether a history of prior cancer cases may affect treatment decisions is still not fully understood.Methods: We identified patients diagnosed with PCa between 2000 and 2014 from the Surveillance,Epidemiology,and End Results(SEER)linked database.We further made propensity score matching and then compared all-cause and cancer-specific survival between patients with and those without a prior cancer.Cox proportional hazards models and Kaplan-Meier analysis were used for survival comparison.We found the type of cancer with greatest impact on survival of prostate cancer through statistical analysis.We further investigated whether there was interaction between those two cancer cells cases cells invasion,migration,and proliferation capacity enhancement by cell growth,cell cloning,transwell extracorporal migration,and invasive experiments.All statistical analysis were achieved by R software(Version3.4.0,R Foundation,Vienna).Two-tailed p value less than 0.05 was considered as statistical significance.Results: A total of 153,255 patients with PCa were included for analysis,of whom5,939 had a history of prior cancer,including hematologic and lymph(11%),intestine(19%),urinary system(36%),head and neck(9%),lung(5%),skin(12%)and others(8%).Patients with a prior cancer had a worse prognosis compared with those without a prior cancer(all-cause death: HR=2.74,95%CI(2.63-2.87),P<0.001;cancer-special death: HR=3.98,95%CI(3.70-4.27),P<0.001).Importantly,cancers in urinary bladder prior to PCa had a most adverse impact on all-cause(HR=5.00,95%CI:(3.70-4.27),P<0.001)and cancer-specific death risk(HR=10.45,95%CI(9.40-11.62),P<0.001).Through cytological experiments,we found that the bladder cancer cells T24 with the liquid supernatant of prostate cancer cells DU145 could enhance the capacity of invasion,migration and proliferation and the prostate cancer cells DU145 with the liquid supernatant of bladder cancer cells T24 could also enhance the capacity of invasion,migration and proliferation(P<0.05).Conclusions: Prior cancer have a negative impact on prognosis of patients with PCa,which is most evident in presence of a prior urinary bladder cancer.Prostate cancer cells and bladder cancer cells have some interaction to enhance the capacity of invasion,migration and proliferation.Our results provide epidemiologic evidence with low between-group bias,large sample size and long-term follow-up,highlighting the need for site-,urinary bladder in special,and interval-time-based clinical management for patients with PCa who had a prior cancer.