Early stage prostate cancer, like most tumors, is small and remains latent in the prostate with few symptoms. The tumor then grows larger and, like BPH, causes narrowing of the urethra, resulting in a series of urinary symptoms similar to BPH, such as frequent, urgent, and painful urination. Because of this, this stage of prostate cancer can be easily confused with BPH. After this stage, prostate cancer will continue to grow and eventually penetrate the surface of the prostate and invade the surrounding organs, and in severe cases, acute urinary retention, hematuria and incontinence may occur. As prostate cancer continues to develop, tumor cells will continue to break away from the original tumor and spread to other organs in the blood or lymphatic fluid. Bone is the most common place for prostate cancer cells to metastasize. Once bone metastases occur, bone pain occurs, especially in the lower back, sacrum and hip. There is also an increased risk of pathological fractures and even paralysis of the lower limbs. When prostate cancer progresses to this stage, prostate cancer is already advanced and it is difficult to achieve a cure by current medical means.