Staging also depends on the extent and location of cancer outside the confines of the prostate. Another important measure, the Gleason score, gauges the probable aggressiveness of the tumor based on the cellular differences of the cancer. Tumor cells that look similar to normal cells tend to be less aggressive, while those distributed randomly with uneven edges are likely to spread rapidly. Two numbers, each from 1 to 5, are assigned. The higher the numbers when the two are added, the more aggressive the tumor is likely to be.
Doctors also examine the ploidy, or number of sets of chromosomes in a cancer cell.
Diploid cells, for example, have a complete set of normally paired chromosomes and tend to grow slowly and respond well to therapy. Recently, some doctors have begun using Partin Tables, a scoring method developed at Johns Hopkins University that uses PSA, Gleason number, and staging to predict if the disease is confined or has spread to other sites. Treating the disease Armed with diagnostic data, patients and their doctors must then decide on a treatment course. It is at this point that patients must be well educated, says FDA's Fourcroy. And they must also remember to include their partners in the decisions because they will be affected by the course of action too.