Durham, N.C. — Prostate cancer is the most common cancer in American men, and in most men it grows very slowly. 

Despite that, it's important for doctors to know which men have slow-growing tumors and which men have more aggressive forms of prostate cancer in order to plan treatment strategies. Thanks to new imaging technology, identifying men who can afford to wait – and those who can't – is becoming easier. 

Called parametric MRI, the new type of MRI imaging provides more detailed information that can make treatment decisions simpler, including 3D models that give doctors a clearer picture of growing tumors. 

"It helps me with operative planning and decisions on where to cut or excise the prostate," Duke University Hospital urologic surgeon Thomas Polascik said. 

Duke radiologist Rajan Gupta says the MRI imaging combines structural images with pictures than can actually reveal cancer activity. Doctors can make judgments about how cancer is spreading, knowledge that helps them decide how quickly and aggressively the need to treat tumors.

The new technology could go a long way to making sure 69-year-old Charlie Speight makes it through his battle with prostate cancer. Speight discovered he had prostate cancer after a PSA blood test. His doctor sent him to a urologist, who discovered he had an advanced tumor. 

The MRI imaging helped Speight and his wife Susan make their choice for what type of surgery he'll get. 

"There's more cancer than we thought," Susan Speight said. "It may have moved outside the capsule, as they say." 

Charlie says he just wants to have the surgery and get back to retirement. 

"If it's got cancer, I want it gone," he said. 

The Parametric MRI machine is not in widespread use, but rather in select academic hospitals like Duke to further study their best use.