Association of radiotherapy with secondary pelvic cancers in male patients with rectal cancer
摘要
We aimed to explore the risk of secondary prostate cancer (SPC) and secondary bladder cancer (SBC) in male rectal cancer (RC) patients after radiotherapy (RT) and to assess survival outcomes.
MethodsThis large population-based study included men with RC from nine registries in the Surveillance, Epidemiology, and End Results (SEER) database between 1973 and 2015. Fine-Gray competing risks and Poisson regression were used to assess the RT-related risk of SPC and SBC in patients who received RT versus those who did not (NRT).
ResultsAfter exclusion, 28,886 RC patients were included in further analysis, including 9763 RT-treated patients (33.8%) and 19,123 patients not treated with RT (66.2%). In competing risk regression analysis, RT was associated with a low risk of developing SPC (adjusted HR = 0.67; 95% CI = 0.64–0.82; P < 0.001) and with a high risk of developing SBC (adjusted HR = 1.44; 95% CI = 1.15–1.80; P = 0.001). In the survival analysis of SPC patients, the NRT group exhibited better 10-year OS and CSS than the RT group (OS: HR = 0.52; 95% CI = 0.43–0.64; P < 0.001; CSS: HR = 0.39; 95% CI = 0.26–0.56; P < 0.001).
ConclusionMale rectal cancer patients receiving RT had a decreased risk of SPC and an increased risk of SBC, and the prognosis of SPC patients in the RT group was worse compared to that of the NRT group. Follow-up and monitoring of SBC and SPC should not be ignored.