Posted 6/12/2017 11:58 PM (GMT 0)
The first number is the predominant pattern when they examine the cells under a microscope. If there are more than one type of cells, they also evaluate the next most common cells found in the sample. The Gleason score is comprised of two different "grades" of cells. 1 and 2 are normal or near normal cells. Grade 3 are cancerous but not aggressive. Hence, those who have a Gleason(3+3) may, MAY be put on watchful waiting or active surveillance as the cancer may not at that point be worth the risks of aggressive treatment. Grade 4 cells look distinctly different from normal cells and grade 5 look totally unlike normal cells.
So in general any Gleason less than 6 is not treated, G6 is up to the individual case. In the case of 7, (4+3) is aggressive and (3+4) is less so, and basically determines how quickly treatment must be pursued. G8 is typically (4+4) and required immediate treatment (though there are sometimes 3+5 and other odd pathologies). G9 may be 4+5 which is difficult to treat, and 5+4 or G10 which is 5+5 typically goes right to HT and chemo and is often fatal, though it may take many years.
There is a move to report only 'grade', 3, 4 or 5, which would simplify things, except for the dramatic difference between 3+4 and 4+3.