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Some heartening statistics were reported last year by the Journal of the National Cancer Institute: the mortality rate for breast cancer dropped nearly five percent between 1989 and 1992, the Largest decline since 1950. The numbers were even more dramatic for young women: between 1987 and 1992, the mortality rate plummeted nearly 18 percent among white women younger than 40.
But discouraging news also surfaced: the mortality rate among black women has gone up, and the number of reported breast cancer cases is rising as well. Twenty years ago a woman’s lifetime risk of breast cancer was one in 12; now it’s one in eight.
Nevertheless, we’re on the verge of a revolution in treating this disease. Researchers now have a clear picture of how a cancer cell becomes a tumor -- and how cells break free from a tumor and glide through the bloodstream to seed a new one in another part of the body. And they better understand how the female hormone estrogen mak
A. They know how a tumor is developed.
B. They know how a new tumor is seeded in the body.
C. They know how the female hormone estrogen makes breast cancer cells grow.
D. They know breast cancer is a death sentence to women.