BPH (hypertrophy vs. hyperplasia)
Q. As a retired physician, I particularly appreciate Harvard Men's Health Watch since it's an easy way for me to learn about new developments in medicine. As a 78-year-old man with an enlarged prostate, I'm particularly interested in your fine articles about BPH. But if memory serves me right, we called the condition "benign prostatic hypertrophy" when I was in practice, but now you call it "benign prostatic hyperplasia." What's the difference?
A. Thanks for your kind words.
Medicine is indeed a rapidly changing science, and you are exactly right about the changing name of BPH. For many years, doctors believed that this common condition resulted from an increase in the size of certain cells in the prostate gland. An increase in cell size is called hypertrophy. It's what makes bodybuilders "bulk up"; in that case, resistance training makes muscle cells bigger and stronger, but these bulging biceps don't contain more cells than those of a 100-pound weakling.
In BPH, prostate cells do get bigger—but the number of cells also increases. An increase in cell number is called hyperplasia—hence the new name. In the case of BPH, both stromal cells and epithelial cells increase; each contributes to the problem, but the stromal cells are the chief culprits. Together, these cells grow into nodules of abnormal tissue that slowly increase in size and number.