ROBERT SMITH, MD: Early on they saw benefits that showed improved response rate, prolonged time to progression, prolonged time to treatment failure, and more clinical benefit with the letrozole group.
CLIFFORD HUDIS, MD: In each one of the studies, there are pros and cons, but for each one of the studies, there is some sort of an advantage seen for the aromatase inhibitor; again, either more effectiveness or greater safety. In direct comparisons in patients with advanced breast cancer, the aromatase inhibitors, as a group, in comparison to tamoxifen, have demonstrated slightly longer time to progression. And they've done that in a setting where they also have slightly fewer side effects.
ANNOUNCER: Side effects of any treatment are important since they affect how well a patient is able to live their life.
ROBERT SMITH, MD: When we look at side effects that occur with the aromatase inhibitors, there are very few. What it's doing is basically blocking estrogen production in the body. So hot flashes are going to be worse. Sometimes there is some change in symptoms such as nausea, which is very mild.
CLIFFORD HUDIS, MD: They are associated with a little more risk of muscle and skeletal pain, and they may turn out to be a little more harmful in terms of bone density; that's osteoporosis.
ROBERT SMITH, MD: But in general the side effects are very minimal and well managed.
ANNOUNCER: These reduced side effects result in fewer concerns about problems that could arise from other treatments, as in the case with tamoxifen.