I'll second (third?) the above. Nomograms are an attempt to induce a formula for some clinical outcome (PSA rising, metastasis, probability of dying of PC, etc.) from some set of statistical data. Each one correctly portrays the results a particular research team found, but the results will vary for the reasons stated above (one institution's effectiveness, different age of patients, small sample, etc.)
You can get closer to the underlying data at the American Cancer Society's website /www.cancer.nexcura.com/Secure/InterfaceSecure.asp?CB=265
so you can sort of pick and choose which study matches your conditions. In some cases they try to do the work for you.
But it all comes down to the problem that your odds of whatever are either zero or one, but you'll never know until after the fact.