[Two cases of second bladder cancer after radiotherapy for prostate cancer]

Second cancer after radiotherapy is defined that more than five years have passed from radiotherapy for primary cancer in case of solid and different histological cancer and second cancer exists into or near radiotherapy area. While it has been not frequent that a treatment for urological cancers causes second cancer, there is the possibility that second cancer increases by recent increase of radiotherapy for prostate cancer. We report two cases of second bladder cancer after radiotherapy for prostate cancer. It is important to take second cancer into consideration for long-term after the patients are treated with radiotherapy.