Dr. Eduardo Ibarra checks the blood pressure of Carmen Garcia Lavoy in the Toa Baja area of Puerto Rico. He's been making house calls in the area with nurse Erika Rodriguez.
Breasts deemed "dense" in a mammogram tend to have less fatty tissue and more connective tissue, breast ducts and glands, doctors say. About 40 percent of women between the ages of 40 and 74 have dense breasts.
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Radiation therapy is effective in treating breast cancer but typically requires dozens of visits over five to seven weeks. A newer protocol takes just three weeks.
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