What Does The Grade Of The Tumor, Rate Of Cell Growth And Differentiation Mean?

Dr. Larry Norton answers the question: 'Grade Of Tumor, Rate Of Growth?'

By
Larry Norton, M.D., Deputy Physician-in-Chief, Breast Cancer Programs, Memorial Sloan-Kettering Cancer Center
May 8, 2008, 4:18 PM ET
1 min read

— -- Question:What does the grade of the tumor, rate of cell growth and differentiation mean?

Answer: Looking at the tumor under the microscope is extremely important for determining what to do next (prognosis) and appropriate choice of therapy. One of the things we look at under the microscope is how aggressive the cells are: are the cells dividing rapidly? Are they very abnormal and look very different than the normal breast cells? We call that 'differentiation.'

'Well-differentiated' means they're close to normal breast cells. 'Poorly-differentiated' means that they are very different than normal breast cells and are therefore more malignant -- have a greater tendency of growing, have a greater tendency of spreading in the breast and to other tissues in the body.

'Grading' is a number that we can put on the differentiation so that when doctors communicate, they can communicate how close the cells are to normal or how far they are from normal.

Next: What Is The Role Of OncotypeDX And For What Types Of Tumors Is It Used?

Previous: What If I Have Two Different Tumors In Different Parts Of My Breast, Such As The Upper-Outer Area And The Lower-Inner Area?