What're the chances of having prostate cancer for age 25?

Essentially 0%. : Prostate cancer has one of the strongest relationships between age and any human malignancy. In data from the national cancer institute's surveillance, epidemiology and end results (seer) program, 0.0% were diagnosed under age 34; 0.6% between 35 and 44; 9.5% between 45 and 54; 31.6% between 55 and 64; 35.5% between 65 and 74; 18.6% between 75 and 84; and 4.1% 85+ years of age.

Almost impossible: Extremely rare to almost impossible. In medicine, nothing is 100% but i would say it is 99% unlikely to have prostate cancer at 25.