Is all prostate cancer testosterone receptor-positive?
—Mike Hutchins, MD, Missoula, Mont.

Yes, all prostate cells have androgen receptors. This is the reason prostate cancer will respond to androgen deprivation. What has puzzled urologists for more than 50 years now is the mechanism of resistance to androgen ablation. Much attention has focused on the androgen receptor as a possible key mediator in the progression to hormone-refractory disease. There is a good discussion of several possible theories in Prostate Cancer: Principles and Practice (Kantoff PW, Carroll PR, and D’Amico AV, eds. Philadelphia, Pa.: Lippincott, Williams & Wilkins; 2002: chap 9).
—David T. Noyes, MD